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Dirty Shirt
11th of April 2005 (Mon), 18:45
I keep reading things about stepping down or up the F stop on there lens. How do you do this? sorry for the newbie question. I have a 20D.

raylks
11th of April 2005 (Mon), 18:52
You get a EF70-200L f4.0L right? To stop down this lens, say, by 1-stop, then you set the aperture value to f5.6 and shoot.
To stop down, say by 2-stops, then you set the aperture value to f8.0.

kawter2
11th of April 2005 (Mon), 18:54
what mode are you using? In P and AV you can roll the dial right above the shutter release. If you are using any think counter clockwise of (on the dial that is) [P]. you can't control it at all

Dirty Shirt
11th of April 2005 (Mon), 18:56
Yes, I shot in the custom modes. Mostly in AV.

Now what does this do for you?

Headcase650
11th of April 2005 (Mon), 19:23
Makes youe depth of field longer, sometimes makes the lens sharper. and doubles your shutter speed for the same exposure but that can be delth with if you pump up your ISO.

tim
11th of April 2005 (Mon), 19:24
Stopping down a lens is just reducing the aperture. Say you have an F2.8 lens, stopping it down means reducing the site of the aperture - ie setting it to F4, F8, or smaller (higher F number is smaller aperture). "Stopping down" doesn't say by itself how much you're doing it. In Av mode this is done by twirling the dial beside the shutter button.

I strongly recommend you take a photography course somewhere near you. I did one that was 8 weeks at 2 hours per week in the evening, and it was invaluable. Without it you should get better, with it you will understand and get better more quickly.

smittymike19
11th of April 2005 (Mon), 19:27
man what are you doing buying a 20d if you know this little about cameras? you should start off witha basic point and shoot, learn that, then move up..seems like a little overkill, if you dont know what this means.

JaertX
11th of April 2005 (Mon), 19:28
Do a search on RTFM.

Had to say it before someone else did, but I'm not better about such questions.

But seriously, AV is for depth of field control, TV is for stopping or blurring motion. Basically.

kawter2
11th of April 2005 (Mon), 19:42
With freinds like this...


Last two posts are uncalled for, and I hope people don't treat you as bad when you ask your questions

JaertX
11th of April 2005 (Mon), 19:56
With freinds like this...


Last two posts are uncalled for, and I hope people don't treat you as bad when you ask your questions

awe come on. it's meant in good nature. besides, hopefully it will help the guy out.

Az2Africa
11th of April 2005 (Mon), 20:38
Hang in there and disregard the point and shoot remark(i know he was just kidding).8 months ago I didn't know what an f stop was either; but I bought a digital rebel first and now have a 20d. I have learned a great deal from the guys here on the forum and they have alway been patient and helpful But you should also do as they say and as I did. which is to read everything you can on the subject and try to find classes if possible. I even went to a 2 days N*k*n School of Photography class. I bought the best to start with so I could learn UP to it and not waste money on gear that I would have to sell later at half price to move up.Presently. this beginner has the 20D, 50 1.8,18-55 kit lens28-135IS,70-200 2.8L IS and 100-400 IS and all based on reccomendations I found here on the forum. So do as they say and read a lot and Shoot Shoot Shoot!!

markubig
11th of April 2005 (Mon), 20:44
Hi Chris -
This is how I understand it. I am not a pro nor have I taken classes, so it might help that you hear it from a layperson. Think of the aperture as a circle (or hole) that lets light in to control Depth of field, or DOF, which is basically how much of your view is in focus. F/1.8, for example, means that the circle is pretty large (shallow DOF), which would let a lot of light in, but would only leave objects in the same plane of your subject in sharp focus. Shallow DOF is how people get that sharp subject with a blurred background (a.k.a. bokeh). OTOH, F/11 means that the circle/aperture is smaller, reducing the amount of light getting in, but increasing the DOF. In other words, the more of your view will be in focus. When someone tells you to stop a lens down, they are telling you to decrease the aperture/circle (increase f-stop number) . Full F stops from 1.0 are f/1.0, f/1.4, f/2.0, f/2.8, f/4.0, f/5.6, f/8, f/11 . . . and i don't know where it goes from there.

So anyway, as an example, if someone tells you to stop down a lens by . . let's say 2 stops . . . they mean for you to go from f/2.0 to f/4.0 (or f/2.8 to f/5.6 or f/4.0 to f/8.0). it gives you a sharper picture.

Sorry if I got into too much detail and sorry if you knew a lot of this. I guess I typed this long explanation to see if I really comprehended the subject.

Can someone please correct anything that is incorrect in this post? My apologies, in advance, for any errors.

Good luck!

***EDIT*** I CORRECTED THE FULL F-STOPS FROM F/1.0. SORRY FOR THE ERR

nosquare2003
11th of April 2005 (Mon), 20:55
Full F stops from 1.4 are f/1.4, f/1.8, f/2.8, f/4.0, f/5.6, f/8, f/11 . . . and i don't know where it goes from there.

So anyway, as an example, if someone tells you to stop down a lens by . . let's say 2 stops . . . they mean for you to go from f/1.8 to f/4.0 (or f/2.8 to f/5.6 or f/4.0 to f/8.0). it gives you a sharper picture.



Nope, one stop from 1.4 should be 2.0 (not 1.8).

2 stops from 1.8 would be around 3.6 (edited)

pcasciola
11th of April 2005 (Mon), 21:01
Not bad, Mark. Everything was right except that f/1.8 is not a full stop, f/2 is, so f/2 to f/4 would be two stops. Without getting into the whole math of it, every full stop down represents an aperture that is half the size, which lets in half the light, and requires a shutter speed that is twice as long for the same exposure.

I like this virtual camera for seeing the effects of aperture on depth of field and shutter speeds:

http://www.camerasinteractive.com/index.php

markubig
11th of April 2005 (Mon), 21:01
Nope, one stop from 1.4 should be 2.0 (not 1.:cool:.

2 stops from 1.8 would be around 3.5 (or 3.6)

http://www.photography-on-the.net/forum/images/smilies/icon_redface.gifhttp://www.photography-on-the.net/forum/images/smilies/icon_redface.gifps! i knew that i was getting myself knee deep . . . sorry about that

.

pcasciola
11th of April 2005 (Mon), 21:11
The simplest way to remember all the numbers is that they all start from 1 and 1.4 and double from there. So it's 1, 2, 4, 8, 16, 32 and then 1.4, 2.8, 5.6, 11, 22, etc.

cmM
11th of April 2005 (Mon), 21:12
But seriously, AV is for depth of field control, TV is for stopping or blurring motion. Basically.
Basically, no!

AV is a shooting mode in which you control aperture

TV is a shooting mode in which you control shutter speed.

Now what are the advantages of both is a different story.

To answer the poster's question, you gotta keep in mind that a "stop" is what we generally reffer to when we measure light. And "F stop", on the other hand, is a measurement for aperture.

robertwgross
11th of April 2005 (Mon), 21:16
If you are inclined toward math, you can start the f-stops series at 1, and then multiply by the square root of two, then repeat again and again.

Square roots are easy, aren't they?

---Bob Gross---

markubig
11th of April 2005 (Mon), 21:16
The simplest way to remember all the numbers is that they all start from 1 and 1.4 and double from there. So it's 1, 2, 4, 8, 16, 32 and then 1.4, 2.8, 5.6, 11, 22, etc.

whew! thanks for bailing me out, Phil!!!

http://www.photography-on-the.net/forum/images/smilies/icon_redface.gifhttp://www.photography-on-the.net/forum/images/smilies/icon_biggrin.gifhttp://www.photography-on-the.net/forum/images/smilies/icon_redface.gifhttp://www.photography-on-the.net/forum/images/smilies/icon_biggrin.gif

markubig
11th of April 2005 (Mon), 21:24
If you are inclined toward math, you can start the f-stops series at 1, and then multiply by the square root of two, then repeat again and again.

Square roots are easy, aren't they?

---Bob Gross---

ha! i can't even multiply 2x4 without a calculator anymore . . . http://www.photography-on-the.net/forum/images/smilies/tongue3.gifhttp://www.photography-on-the.net/forum/images/smilies/tongue3.gifhttp://www.photography-on-the.net/forum/images/smilies/tongue3.gif

.

tim
11th of April 2005 (Mon), 21:26
The rule of thumb I use is start and 1 and multiply by 1.4 . Bob has it right with the square root of 2, but 1.4 is close enough for everyday use.

Dirty Shirt
11th of April 2005 (Mon), 21:36
man what are you doing buying a 20d if you know this little about cameras? you should start off witha basic point and shoot, learn that, then move up..seems like a little overkill, if you dont know what this means.

Gee thanks *******.

Dirty Shirt
11th of April 2005 (Mon), 21:37
awe come on. it's meant in good nature. besides, hopefully it will help the guy out.

Atleast I have the balls to ask newbie questions.

Dirty Shirt
11th of April 2005 (Mon), 21:41
Thanks to everyone who responded. I understand! Now I'm off to the corner to RTFM! :p

Titus213
11th of April 2005 (Mon), 22:14
Thanks to everyone who responded. I understand! Now I'm off to the corner to RTFM! :p

I don't know about the 20D but the 300D has a PDF manual and I loaded it to the PC so I can read while browsing the forums. I think a person should buy the best equipment they can afford and enjoy it. Keep asking questions. I enjoy reading the response too.

smittymike19
11th of April 2005 (Mon), 22:29
I don't know about the 20D but the 300D has a PDF manual and I loaded it to the PC so I can read while browsing the forums. I think a person should buy the best equipment they can afford and enjoy it. Keep asking questions. I enjoy reading the response too.

ok maybe my point and shoot comment seemed a bit harsh. i retract it. but you should probably use google in the beginning, too get the SUPER basics down a bit. then come on here when you cnat figure something out. PM me and ill be more than happy to point out a few good sites for you to start on. good luck:)

Dirty Shirt
11th of April 2005 (Mon), 22:37
I don't know about the 20D but the 300D has a PDF manual and I loaded it to the PC so I can read while browsing the forums. I think a person should buy the best equipment they can afford and enjoy it. Keep asking questions. I enjoy reading the response too.

Thanks! I do have the pdf's.

Dirty Shirt
11th of April 2005 (Mon), 22:37
ok maybe my point and shoot comment seemed a bit harsh. i retract it. but you should probably use google in the beginning, too get the SUPER basics down a bit. then come on here when you cnat figure something out. PM me and ill be more than happy to point out a few good sites for you to start on. good luck:)

Thanks. Why not just post them so everyone can use them. I appreciate the help.

Muffin Princess
12th of April 2005 (Tue), 05:07
I'm sorry but I agree with the person who said maybe you shouldn't have bought the kit you bought if you don't know what apertures are. I'm not being harsh or anything, but you've obviously spent a lot of money, what with your L lens and everything, and it might turn out that you end up hating photography as it's a lot more complicated than people originally think, and then you'll have wasted your money.

I've worked with 2 people who have been there (Jessops) for 7 months, selling cameras to people, they STILL don't know what apertures and shutter speeds are. One of them refuses to learn; she gets me to serve all the customers and then wanders off instead of listening, and the other one if just interested in technology and how many mega pixels they all have instead of actually learning about photography. It winds me up no end. So one day I spent about half an hour writing up 2 sides of an A4 sheet explaining how aperture and shutter speed affect DOF, blur and how they affected by light levels etc etc, and they looked at it for a couple of seconds and then chucked it in a pile of paper; they still know nothing! Grrr!

Sorry, Dirty Shirt, I'm not comparing you to them, they just wind me up; at least you're willing to learn! good luck :)

dave_bass5
12th of April 2005 (Tue), 05:37
Sorry guys at the risk of getting flamed can someone tell me when you need to stop down or how you know when to.
Ive had a 350xt for a couple of weeks coming from a Canon s400 (so have done the P & S route) and have read loads about taking pics and i know how to stop down but not when to.
Is this just a personal thing or are certain lenses in need of this to get the best out of them?
like i said im learning (and very keen to) but sometimes you read things metioned but dont always understand the phrase or whatever.
again sorry if im wasting your time but thanks for any advice

dave.

Andy_T
12th of April 2005 (Tue), 05:48
Normally, a lens is not completely sharp wide open (at the largest aperture) and sharpness improves when you stop it down.

Not completely true, but the more expensive a zoom lens, the less you normally have to stop it down to get sharp images.

Best regards,
Andy

dave_bass5
12th of April 2005 (Tue), 06:04
Thanks for the reply Andy.
So i guess i just need to take lots of pics and try different settings.
If in P mode i use the program shift to stop the lens down the speed also changes to keep the exposure correct (i think), will this still have the same effect on the picture or do i need to make sure the speed stays the same (Manaul mode)?
At the moment i only have the kit lens but will buy another, maybe a 55-200 when i can afford it.
thanks again

Dave.

Andy_T
12th of April 2005 (Tue), 09:42
Dave,

that's the way it should be (shutter speed changes). Otherwise, the image would be too dark, as the amount of light that can come in at a certain time is reduced.

Do some more research on the 55-200, not everybody is completely happy with it.

Best regards,
Andy

dave_bass5
12th of April 2005 (Tue), 09:48
Thanks again Andy.
i think i sort of expected that, just wanted confirmation inm on the right track.
As for the lens, yes ill research it first. i had a loan of the mk1 version and i kept getting the dreaded err99 in any mode other than portrait but im hoping the mk2 will be better.
i do like the kit lens though.

Thanks

Dave.

smittymike19
12th of April 2005 (Tue), 10:53
Sorry guys at the risk of getting flamed can someone tell me when you need to stop down or how you know when to.
Ive had a 350xt for a couple of weeks coming from a Canon s400 (so have done the P & S route) and have read loads about taking pics and i know how to stop down but not when to.
Is this just a personal thing or are certain lenses in need of this to get the best out of them?
like i said im learning (and very keen to) but sometimes you read things metioned but dont always understand the phrase or whatever.
again sorry if im wasting your time but thanks for any advice

dave.

this is a joke right? ok the point oif a forum is to learn right? ok, well here is a post from earlier in this THREAD:mad: . read read read....


This is how I understand it. I am not a pro nor have I taken classes, so it might help that you hear it from a layperson. Think of the aperture as a circle (or hole) that lets light in to control Depth of field, or DOF, which is basically how much of your view is in focus. F/1.8, for example, means that the circle is pretty large (shallow DOF), which would let a lot of light in, but would only leave objects in the same plane of your subject in sharp focus. Shallow DOF is how people get that sharp subject with a blurred background (a.k.a. bokeh). OTOH, F/11 means that the circle/aperture is smaller, reducing the amount of light getting in, but increasing the DOF. In other words, the more of your view will be in focus. When someone tells you to stop a lens down, they are telling you to decrease the aperture/circle (increase f-stop number) . Full F stops from 1.4 are f/1.4, f/1.8, f/2.8, f/4.0, f/5.6, f/8, f/11 . . . and i don't know where it goes from there.

So anyway, as an example, if someone tells you to stop down a lens by . . let's say 2 stops . . . they mean for you to go from f/1.8 to f/4.0 (or f/2.8 to f/5.6 or f/4.0 to f/8.0). it gives you a sharper picture.

Sorry if I got into too much detail and sorry if you knew a lot of this. I guess I typed this long explanation to see if I really comprehended the subject.

Can someone please correct anything that is incorrect in this post? My apologies, in advance, for any errors.

Good luck!

smittymike19
12th of April 2005 (Tue), 10:54
Thanks. Why not just post them so everyone can use them. I appreciate the help.

all of the great links are posted under the STICKY sections. have a look.

http://photography-on-the.net/forum/showthread.php?t=53846

Andy_T
12th of April 2005 (Tue), 11:04
Still, the full stops are f/1.0, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11, 16, 22, 32

Every one is roughly its predecessor multiplied by 1.4 (square root of 2)

Best regards,
Andy

trustwoody
12th of April 2005 (Tue), 11:29
Even basic questions can have answers that can be doctoral dissertations. Dirty Shirt, the answer to that question could be half of a photographers Bible. You can go a long ways in gaining information in the answer to your question. As suggested if you are a math geek you could spend many pleasant hours burning calculator buttons and if you are a light geek or a DOF or a Lens geek... you get my point. Anyway, I respect the question and hope that you will sincerely seek after the answer and then start asking "Why do you stop down a lens?" Then, "When do you stop down a lens? The answers are what make this discipline an art.

dave_bass5
12th of April 2005 (Tue), 11:36
smittymike19 i hope your not refering to my question as a joke. its certanly not a joke for me trying to learn somthing here.
i wasnt asking how it works or what it means i was asking when to do it and under what circumstances. after all if you step down to get a sharper pic why dosent the camera set it that way in the first place? the answer i believe is it doesnt know what DOF you want but i hear people saying they step down on certain lenes to get a sharper pic or that the lens works at optimal at a certain f-stop but they dont mention DOF and this is what my question was meant to be about.
In fact i DID READ THE POST you mention and understood most of it.
well i hope you get over my previous post, didnt mean to spoil your day.

Dave.

HJMinard
12th of April 2005 (Tue), 12:27
I'm sorry but I agree with the person who said maybe you shouldn't have bought the kit you bought if you don't know what apertures are. I'm not being harsh or anything, but you've obviously spent a lot of money, what with your L lens and everything, and it might turn out that you end up hating photography as it's a lot more complicated than people originally think, and then you'll have wasted your money.

I think what's important is that the deed is done ... it's too late for buying advice. If someone has already purchased expensive gear and is trying to learn how to use it, there is absolutely no point in belittling their decision. Offer constructive advice for learning how to use it ... or move on.

Besides ... point and shoot buyers generally don't learn about apertures, etc. A more constructive bit of advice might be to purchase a relatively inexpensive film SLR to use as a learning tool.

Anyway, if their interest wanes and they decide to unload the expensive gear ... that means more good stuff on the used market for us :)

smittymike19
12th of April 2005 (Tue), 12:38
smittymike19 i hope your not refering to my question as a joke. its certanly not a joke for me trying to learn somthing here.
i wasnt asking how it works or what it means i was asking when to do it and under what circumstances. after all if you step down to get a sharper pic why dosent the camera set it that way in the first place? the answer i believe is it doesnt know what DOF you want but i hear people saying they step down on certain lenes to get a sharper pic or that the lens works at optimal at a certain f-stop but they dont mention DOF and this is what my question was meant to be about.
In fact i DID READ THE POST you mention and understood most of it.
well i hope you get over my previous post, didnt mean to spoil your day.

Dave.

well the thing is that the posts here have done a great job of explaining what the f stops do. it is up to you to determine what you what to do with the camera. I cant advise you to have a short or long DOF, it is your personal preference really. to put it in the easiest terms:
if you want alot of stuff in focus, make the f number big on your lcd
otherwise make it small. it is up to you, the artist to determine what you want to do. :).

guitarman3
12th of April 2005 (Tue), 12:48
Dave, not all of us on this board are pros, including myself, and I thought your question was a good one. Let me take a shot at it.

When to stop down: probably when you want greater depth of field, but of course you need enough light to support the smaller aperture. Or, if you know your lens doesn't perform its best at a particular aperture, you may want to change it to one it does perform well at, again, assuming light is adequate.

In P mode your camera will try to pick a combination of aperture and shutter speed to make the correct exposure, but if the aperture it chooses doesn't fit your goal for the shot, then you'd need to change the settings.

An example might be if you're taking a photo of a group of your relatives posing for a reunion shot. In auto mode the camera may choose a large aperture setting, but since the people are lined up in three rows, the DOF may not be adequate to get the back row in focus. You would want to stop down the lens to increase your DOF and get all three rows in focus.

Maybe my answer is too simplistic and doesn't answer your question. At least I gave it a shot. Maybe some of the pros can expand on my answer.

eosster
12th of April 2005 (Tue), 12:57
Everyone started with baby steps, let it go and maybe help is in order first.

smittymike19
12th of April 2005 (Tue), 13:00
ok I reread my posts and maybe i am being cranky, sorry. The best way I can help is to tell you to help yourself. That is since you are shooting digital (and can take tons of free shots and examine them freely) and now understand the f stop / dof relationship, go outside and do the following:
1.put your camera in "A" mode.
2. use the dial wheel to make your aperture number go as "low" (enlarging aperture) as possible.
3. shoot a landscape..something where you want alot of DOF.
4. dial the aperture to the next fstop and shoot again.
5. do this until you are at the smallest aperture (largest number on your screen).

Go get your brother/friend/wife/dog. Repeat the process. here you will see what settings for portraits you prefer.

Now you will have 30 pictures or so. Take them inside and load them on your computer and view as a slideshow. You will see the DOF change as well as the sharpness of your pictures. when you find the combo that works for you, stop the slideshow and right click on the picture and view the exif info. that will show you your preference for the shot. as i said before we all have different preferences and you need to discover what your preferences are. This will help tremendously teh next time you are setting up your camera. It is hard to tell people what to do as everyone has a different opinion on what they like. Its kinda like going on a car website and asking "whats the best color to buy this car "? youll get a bunch of different answers, but only one will be right. The one that YOU like. :)

dave_bass5
12th of April 2005 (Tue), 13:00
smittymike19 and guitarman thanks for the replies.
Sorry i think i must have worded my orininal question wrong.
I understand what changing the apature does with DOF but when i read about a sweet spot on a lens and a f-number is mentioned its normaly followed by the words sharpness and deeper colours but not always DOF.
maybe its the same thing and ive got it wrong and this is what im trying to find out.
when peole say so and so lens is really sharp at f?.
sorry for any confusion

Dave.

smittymike19
12th of April 2005 (Tue), 13:18
smittymike19 and guitarman thanks for the replies.
Sorry i think i must have worded my orininal question wrong.
I understand what changing the apature does with DOF but when i read about a sweet spot on a lens and a f-number is mentioned its normaly followed by the words sharpness and deeper colours but not always DOF.
maybe its the same thing and ive got it wrong and this is what im trying to find out.
when peole say so and so lens is really sharp at f?.
sorry for any confusion

Dave.

i think i understand. Here is the answer (i hope).
I have the 50/1.8. Supposedly it is sharpest at f value of 3.2. ok so here it is based on may last example
at 1.8 i can take a picture of my dog and get a clear shot of his face, but his behind may be out of focus (narrow dof). At f 32 his body plus the lawn will be in focus. (long dof). Ok so we have that covered. NOW, if i look at the picture with the 1.8 value, i can see the area that is in focus (his face) is not as crisp as I would like. I look at the picture i took at f value of 3.2. (Here is the "SWEET SPOT" of my lens) The area that is in focus (now his face and his body, but the lawn is out of focus) is sharper.
The lens always has some place that is in focus. by changing the f stop to the sweet spot (3.2 in this example) the area that is in focus will just be CRISPER. It is up to you to decide whether you want to give up the short dof in order to get the crisper image. If you want the artistic look of just his face being in focus(1.8, you have to give up that cripsness that you can get at 3.2. If you prefer crispness, take the shot at 3.2, but you get the whole dog in focus.. I hope this helps. just rememeber, all pictures, whether short dof or long dof have SOMETHING in focus, its just that that SOMETHING will be crisper at the sweet area for the lens. whew..:)

dave_bass5
12th of April 2005 (Tue), 13:23
smittymike19 thats the answer i was looking for and even better as im thinking of geting the 50/1.8
thanks again

Dave.

rdenney
12th of April 2005 (Tue), 13:34
The answers are what make this discipline an art.

Or what make this art a discipline.

Rick "knowing artistic photographers (at least as long as their camera's automation is thinking correctly) who don't know an f-stop from a shutter speed" Denney

Incomplete Pete
12th of April 2005 (Tue), 13:41
I think what's important is that the deed is done ... it's too late for buying advice. If someone has already purchased expensive gear and is trying to learn how to use it, there is absolutely no point in belittling their decision. Offer constructive advice for learning how to use it ... or move on.

Besides ... point and shoot buyers generally don't learn about apertures, etc. A more constructive bit of advice might be to purchase a relatively inexpensive film SLR to use as a learning tool.

Anyway, if their interest wanes and they decide to unload the expensive gear ... that means more good stuff on the used market for us :)

[Muffin Princess] OK, I know it's too late now, but I wasn't suggesting he bought a P&S camera. For example, my first purchase was a 2nd EOS 50 with a 75-300mm lens which cost about 130 for the lot. This wasn't too expensive and so, if I had decided photography wasn't for me, then I wouldn't have wasted so much money. I could still learn with this kit and then upgraded![/Muffin Princess]

smittymike19
12th of April 2005 (Tue), 13:42
smittymike19 thats the answer i was looking for and even better as im thinking of geting the 50/1.8
thanks again

Dave.

dont think about getting the 50/1.8 lens, just do it. it is by far the best bang for teh buck for your camera. The narrow dof at 1.8 is amazing. good luck and godspeed. :)

dave_bass5
12th of April 2005 (Tue), 13:50
smittymike19 the reason im thinking about is that i have 50mm on the kit lens. i know a lot of people slate this lens but as a newcomer i dont think its worth me duplicating 50mm untill i get used to things like DOF and slr in general..........or is it? also i keep seeing people with front/rear focusing issues.
I would like the lens as i take a lot of indoor shots of my kids and noticed the other day that a lot of my good shots taken with my s400 were at f/2.8.
Money is always a factor though.

Dave.

smittymike19
12th of April 2005 (Tue), 13:56
smittymike19 the reason im thinking about is that i have 50mm on the kit lens. i know a lot of people slate this lens but as a newcomer i dont think its worth me duplicating 50mm untill i get used to things like DOF and slr in general..........or is it? also i keep seeing people with front/rear focusing issues.
I would like the lens as i take a lot of indoor shots of my kids and noticed the other day that a lot of my good shots taken with my s400 were at f/2.8.
Money is always a factor though.

Dave.

well if money is a factor then you can get by with the kit lens for now. the 50/1.8 is much faster (that is, you can set a larger aperture and thus get a faster shutter speed). You need the larger aperture inside as I was having a big problem with taking indoor shots with my kit lens. I would set the aperture to its largest value (at 50mm its like 5.0). at that value (5.0) i was gettinga shutter speed of like 1/5th of a second. WAY to slow to take pictures of anything non stationary and too slow to hand hold (everything was blurry). buying the 1.8 allows me to get much quicker speeds and eliminate the blurriness, without using the flash. imho, if you plan on taking a bunch of pics inside, you will find the 50/1.8 a very wise buy.

HJMinard
12th of April 2005 (Tue), 13:58
[Muffin Princess] OK, I know it's too late now, but I wasn't suggesting he bought a P&S camera. For example, my first purchase was a 2nd EOS 50 with a 75-300mm lens which cost about 130 for the lot. This wasn't too expensive and so, if I had decided photography wasn't for me, then I wouldn't have wasted so much money. I could still learn with this kit and then upgraded![/Muffin Princess]

Muffin, er ... Pete ... :???:

No, you didn't suggest a point and shoot, but the original complainant you were defending did. Your advice would be excellent prior to purchase, but now we just have to help the newbie get up to speed :)

dave_bass5
12th of April 2005 (Tue), 14:02
smittymike19 stop it. your going to make me go to jessops tomorrow and spend money i dont have.;)
Do you have any samples of hand held indoor shots without flash?

Thanks

Dave

smittymike19
12th of April 2005 (Tue), 14:56
i only use dteh lens indoors once so far really. that was at my nephews bowling bday party. I am looking at the pics here at work and tehy seem much darker then at home on my computer, so one of the monitors if off. Anyway they are better than being harsh and too bright, and at home i have them looking pretty sweet.

dave_bass5
12th of April 2005 (Tue), 15:38
smittymike19 nice pics.i see what you mean about great DOF.
Thanks
Dave.

goldstrikn
12th of April 2005 (Tue), 16:10
Ok I have another newbe question on this subject of F stop and DOF. What is the purpose of the A-DEP selection and the DOF button by the bottom of the lens (in my 20D's case). If I want a narrow DOF (a lot of blurr background) do I press this bottom button? or this just works to get a wide DOF to get everything that it captures in the viewfinder. What I am asking could be a whole new thread, but it may be related to the F stop, won't it ;)

smittymike19
12th of April 2005 (Tue), 16:27
Ok I have another newbe question on this subject of F stop and DOF. What is the purpose of the A-DEP selection and the DOF button by the bottom of the lens (in my 20D's case). If I want a narrow DOF (a lot of blurr background) do I press this bottom button? or this just works to get a wide DOF to get everything that it captures in the viewfinder. What I am asking could be a whole new thread, but it may be related to the F stop, won't it ;)

as i know it the a dep button is basically a landscape mode, it has a very wide dof (small aperture).
teh dof preview allows you to see what the dof will llok like when the shot is taken. to get teh blurred background put your camera in A mode and dial the aperture to the smallest number.

JaertX
12th of April 2005 (Tue), 19:33
Now I'm off to the corner to RTFM! :p

it's good to see you have a sense of humor.

Oh yeah, and in the manual you'll read where TV is for stopping motion or blurring it, and AV is for blurring the background or keeping it in focus(DOF). But hey, that's just what CANON says, don't take my word for it. ;)

markubig
12th of April 2005 (Tue), 20:01
Ok I have another newbe question on this subject of F stop and DOF. What is the purpose of the A-DEP selection and the DOF button by the bottom of the lens (in my 20D's case). If I want a narrow DOF (a lot of blurr background) do I press this bottom button? or this just works to get a wide DOF to get everything that it captures in the viewfinder. What I am asking could be a whole new thread, but it may be related to the F stop, won't it ;)
A-DEP is Automatic Depth of Field AE Mode. helps in getting a wide DOF between a near and far subject. it uses all the AF points and selects the nearest and farthest subjects to be in focus. Good for group photos when you have people sitting/standing in a diagonal row.

the DOF Preview button stops the lens down to the current aperture setting so you can check your DOF through the viewfinder. this button only gives you a preview. If you want a narrow DOF, you need to open up your aperture (smaller value)

jfrancho
12th of April 2005 (Tue), 20:22
well if money is a factor then you can get by with the kit lens for now. the 50/1.8 is much faster (that is, you can set a larger aperture and thus get a faster shutter speed). You need the larger aperture inside as I was having a big problem with taking indoor shots with my kit lens. I would set the aperture to its largest value (at 50mm its like 5.0). at that value (5.0) i was gettinga shutter speed of like 1/5th of a second. WAY to slow to take pictures of anything non stationary and too slow to hand hold (everything was blurry). buying the 1.8 allows me to get much quicker speeds and eliminate the blurriness, without using the flash. imho, if you plan on taking a bunch of pics inside, you will find the 50/1.8 a very wise buy.This i swhere we complicate the process by adding a third variable. If the shutter speed is too slow, less than 1/focal length, then you can choose a higher ISO speed. This emulates higher speed films, it "sensitivity to light," if you will. If you were in AV mode, the camera would increase the shutter speed for a proper exposure. I have used the kit lens in many low light situations. You just have to understand the limitations of the lens: It isn't going to be a tack sharp portrait with cool bokeh (google it or use the search here). I have some great B&W shots of live bands shot at ISO 1600, about 1/60 sec. at all focal ranges (including 50mm, and I have the 50mm 1.4 USM - way more appropriate for this) that I just could not get with any other lens. It depends on what you're going for.

guitarman3
12th of April 2005 (Tue), 20:43
Dave, my next purchase will be the 50mm f1.8. I have basically the same set up you do as far as lenses go and I know I'll be duplicating the 50mm focal length (80mm on my 350D). But the kit lens is slow --only f3.5--compared to the prime 50mm lens at f 1.8. I took a bunch of indoor shots of my granddaughter with the kit lens and she just didn't understand that she had to hold still! All the shots were blurry, even at ISO 1600. The shutter speed was too slow to stop her movement.

With the f 1.8 lens it will let in 2 to 4 times as much light (one of the pros can help me here!), so that shutter speed can be shortened 2 to 4 times as much and stop her movement. Also, generally speaking, fixed length lenses have better optics than a similar zoom lens (remember I said generally speaking!!). So you'll probably get sharper photos with the prime lens.

Since the X factor of my 350D makes this an 80mm lens on my camera, it is just about right for portraits--sharp ones--especially if you use that "sweet spot" smittymike was talking about.

Sure it's a cheap $80 lens but I understand if you don't have the money it makes it tough. That's my situation too, but I gotta get one before they're all gone!!

EDIT: At the time I thought the nifty fifty was all I'd be able to afford right now but I sold a few things laying around the house and accumulated enough for, and ordered the EF 70-200 f/4L. I still want the nifty fifty and hope it won't be long!

Maureen Souza
12th of April 2005 (Tue), 21:43
Personally, I think it is okay to start out with a big camera and little knowledge as long as you have the willingness to learn your camera as you go. It can be a great teacher and as you get more comfortable trying all the modes, you will get better and better. I had a pretty good basis of knowledge when I got my 20D but it didn't make me a good photographer with it right off the bat. Actually, I am just now getting more good shots than bad and was pretty pleased with my last couple of outings with it. Perserverence, reading the manual a few times and practice are the best teachers!!!

Fer
12th of April 2005 (Tue), 21:58
Personally, I think it is okay to start out with a big camera and little knowledge as long as you have the willingness to learn your camera as you go. It can be a great teacher and as you get more comfortable trying all the modes, you will get better and better. I had a pretty good basis of knowledge when I got my 20D but it didn't make me a good photographer with it right off the bat. Actually, I am just now getting more good shots than bad and was pretty pleased with my last couple of outings with it. Perserverence, reading the manual a few times and practice are the best teachers!!!

I agree Maureen.

Chris, I personally think that you are so willing to learn and you have the courage to ask, so go ahead!, keep asking and shooting and you will see the difference in each pic. ;)

jfrancho
12th of April 2005 (Tue), 22:01
Listen to the ladies...they speak the truth.

dave_bass5
13th of April 2005 (Wed), 01:58
guitarman let me know how you get on with the 50mm f1.8. i think i will get one at some point but just after i got my 350 i got a 420ex and for now that is giving me great indoor pics. im bouncing the flash off the ceiling so no harsh light.
thanks all for the replies. i have learnt a lot just in this one thread.

Dave.

Maureen Souza
13th of April 2005 (Wed), 04:00
I agree Maureen.
;)

Right on sister friend!!!! These guys make the biggest fuss over things, don'tcha think:lol: :lol: :lol:

Andy_T
13th of April 2005 (Wed), 05:37
smittymike19 the reason im thinking about is that i have 50mm on the kit lens. i know a lot of people slate this lens but as a newcomer i dont think its worth me duplicating 50mm untill i get used to things like DOF and slr in general..........or is it?

My very quick (unscientific) test showed me that I get pictures that I consider sharp enough (they are sharp to the eye without post-processing when viewed as 100% crop) at 50 mm when I use
- my 50/1.8 @ f/2.8,
- my Tamron 28-75/2.8 XR DI @ f/4.0 or
- my 18-55 kit lens at f/8.

That is quite some difference, and not bad for an additional 80$, eh?

(Of course, this is much sharper than you would really need for 3x5 prints, but it might be important for printing 8x10 or larger enlargements.)

also i keep seeing people with front/rear focusing issues.

You will not see front or rear focusing as much with a wide DOF at f/5.6, although it might be there.
But the very thin DOF of f/1.8 or f/2.0 shows if the focus is off.

However, in 90% when a user complains about front- or backfocusing, it's normally not the cameras fault :wink:

I would like the lens as i take a lot of indoor shots of my kids and noticed the other day that a lot of my good shots taken with my s400 were at f/2.8.


That is TOTALLY DIFFERENT.

The S400 has a very small sensor, so for technical reasons the DOF at f/2.8 is way larger than at a DSLR.
IMO, the DOF at f/2.8 of the S400 is roughly equivalent to f/8 at a DSLR.

There is NO WAY to get images like those posted by Smittymike with an S400 without applying a gaussian blur in Photoshop.

You should also bear that in mind when you try to take a landscape shot with your DSLR.

Best regards,
Andy

dave_bass5
13th of April 2005 (Wed), 06:06
Thanks for clearing that up andy.
this is the reason i upgraded to the 350 (and have very limited idea of DOF) as i had no control on the s400.
i can see that i wouldnt use the 50/1.8 @ f/2.8 much because of movement. you cant get a 10month old to stay still so again i would be stopping down for better DOF and better chance of getting sharper pics so i may as well stay with the kit lens for now.
my flat is quite small and last night i kept the lens at 50mm and took a few shots and to be honest i need a more wide angle than 50mm.
Thanks again

Dave.


Dave.

alfa1six4
13th of April 2005 (Wed), 08:29
Might I suggest this book: Understanding Exposure by Bryan Peterson


www.amazon.com/exec/obidos/tg/detail/-/0817463003/qid=1113401839/sr=8-1/ref=pd_csp_1/104-6424978-4727948?v=glance&s=books&n=507846 (http://www.amazon.com/exec/obidos/tg/detail/-/0817463003/qid=1113401839/sr=8-1/ref=pd_csp_1/104-6424978-4727948?v=glance&s=books&n=507846)


It's only $16 from Amazon. Well worth the investment. Written in plain english. It was originally written before the DSLR age, but all the fundamentals still apply as they did with film. It's been recently revised to include some digital info.

goldstrikn
13th of April 2005 (Wed), 08:46
Might I suggest this book: Understanding Exposure by Bryan Peterson


www.amazon.com/exec/obidos/tg/detail/-/0817463003/qid=1113401839/sr=8-1/ref=pd_csp_1/104-6424978-4727948?v=glance&s=books&n=507846 (http://www.amazon.com/exec/obidos/tg/detail/-/0817463003/qid=1113401839/sr=8-1/ref=pd_csp_1/104-6424978-4727948?v=glance&s=books&n=507846)


It's only $16 from Amazon. Well worth the investment. Written in plain english. It was originally written before the DSLR age, but all the fundamentals still apply as they did with film. It's been recently revised to include some digital info.

I agree with alfa, this book is a wealth of knowledge. Highly recommend.

MarkH
13th of April 2005 (Wed), 16:31
Personally, I think it is okay to start out with a big camera and little knowledge as long as you have the willingness to learn your camera as you go. It can be a great teacher and as you get more comfortable trying all the modes, you will get better and better. I had a pretty good basis of knowledge when I got my 20D but it didn't make me a good photographer with it right off the bat. Actually, I am just now getting more good shots than bad and was pretty pleased with my last couple of outings with it. Perserverence, reading the manual a few times and practice are the best teachers!!!

I would just like to voice my agreement with Maureen. I would also like to voice my vehement disagreement and disappointment with the view that 'Dirty Shirt' should not have bought the equipment he has.

The 20D is an excellent camera, probably the best you can get for the price. The 70-200 F4 has been hailed as the best you can get for the money for a 70-200. I would not hesitate to recommend this combination to anyone who can afford it and is happy with the size and weight of that equipment. It is easy to select an auto mode and get good pictures with no technical understanding. It seems that 'Dirty Shirt' is keen on moving up to the creative modes and developing an understanding of the advanced control of the camera, therefore he definately should NOT be using a P&S (the worst type of camera to learn about DoF) and a film SLR is also a poor choice for learning and experimenting with (due to a cost per shot and lack of quick easy review).

My advice to 'Dirty Shirt' is to use the 20D to the full, take plenty of pics (digital costs practically nothing per shot, so don't hold back) and check the settings used when looking at different shots on the PC (EXIF data is useful for learning). Understand that you have the right equipment and your photography will only improve as you learn.

O/confusion
13th of April 2005 (Wed), 20:08
Might I suggest this book: Understanding Exposure by Bryan Peterson.[......]It's only $16 from Amazon. Well worth the investment. Written in plain english. It was originally written before the DSLR age, but all the fundamentals still apply as they did with film. It's been recently revised to include some digital info.

Couldn't agree more. I've been shooting film exclusively--until I took the recent scary full-on dive into digital with the 20D--and using the same two totally manual bodies that I started out with back in the mid '70's.

Even though I've been using that now dated (but still reliable) gear for so long, and have never stopped reading and studying over the years, I've found this book to be a valuable, clearly set out, and straightforward reintroduction to the fundamentals that I think all photographers owe it to themselves to learn to grasp and internalise--and it also had a few welcome tips to offer that I'd not come across before.

Do yourself an enormous service and buy this book. Read it until the pages start to fall out from wear. Same with any and all equipment manuals you have. If you do this in tandem with your hands-on practice, I guarantee you'll learn much faster and retain more than if you just rely on trial and error alone.

It's an exciting time for you, even though it can often feel somewhat daunting at the start; embrace it, live it, and enjoy!

Wishing you a lifetime of learning and striving to be the best you can,

Terry

Maureen Souza
13th of April 2005 (Wed), 23:44
Might I suggest this book: Understanding Exposure by Bryan Peterson
.

I just read this book this last week and it was awesome. I'm going to read it one more time, just for good measure!

alfa1six4
14th of April 2005 (Thu), 05:19
I just read this book this last week and it was awesome. I'm going to read it one more time, just for good measure!

I just started reading it again also Maureen! According to the book, there are about 6 technically correct exposures(stops) of a subject. However, there is only about one or two creatively correct exposures. And that's where learning how to control DOF with aperture and then adjusting Tv or ISO to make a pleasing shot. That was the most important lesson I learned and am still working on, how to make a creatively correct exposure. Rather than worrying where my lens is it's absolute sharpest and adjusting everything else around that setting.

smittymike19
14th of April 2005 (Thu), 07:12
2 things i just bought the understanding exposure book, and let the point and shoot comment die already. both myself and the other poster who made the comments retratcted them. as a matter of fact i have spent a considerable amount of time helping him out. Its ok, he can spend his money however he wants. to me it really was a question of overspending. too amny times in our society we have people way above their heads financially. we have more credit card debt in our america than any other country in the world. we are grossly undersaiving for our retirements, and most people have little to no savings. I have read here a couple of people who have said yeah i just got my tax refund, how do i spend it? it just makes me very nervous to hear people not having enough money saved to go out and buy whatever they want. in fact if you dont have an extra $1000 laying around you should be saving your tax refund, you never know when youll really need it. sorry for being the voice of reason, but dropping $2000+ grand on equipment that you have no idea how to use, seems like a bit of a waste. hopefully it wont be, but then again i guess i wont tell the story about my friend who thought he would love kayaking so he bought a 4000$ kayak (when he could have spent like 800 on a beginners). That thing looks really cool sitting in his garage. I guess i shouldnt overgeneralize, but i just think too many times we are quick to part with hard earned money instead of trying something out, finding out whether we are going to stick with it, then making a plunge. im still not sold taht the rebel isnt an awesome camera. ithink it would have made a great starting point for this guy. just my opinion and sorry for the dissertation, but you struck a nerve. :)

hey i realize we are getting WAYY off target here, this is a camera forum right?

Dirty Shirt
14th of April 2005 (Thu), 12:47
Mike, I'm not sure if the money comment is directed at me in regards to what I purchased as my first dSLR. I perfer to deal in cash as redit cards are just evil.

I just want to thank everyone again for posting and offering help. I really appreciate it. There is a lot to read here! Please keep it up.

jfrancho
14th of April 2005 (Thu), 12:53
2 things i just bought the understanding exposure book, and let the point and shoot comment die already. both myself and the other poster who made the comments retratcted them. as a matter of fact i have spent a considerable amount of time helping him out. Its ok, he can spend his money however he wants. to me it really was a question of overspending. too amny times in our society we have people way above their heads financially. we have more credit card debt in our america than any other country in the world. we are grossly undersaiving for our retirements, and most people have little to no savings. I have read here a couple of people who have said yeah i just got my tax refund, how do i spend it? it just makes me very nervous to hear people not having enough money saved to go out and buy whatever they want. in fact if you dont have an extra $1000 laying around you should be saving your tax refund, you never know when youll really need it. sorry for being the voice of reason, but dropping $2000+ grand on equipment that you have no idea how to use, seems like a bit of a waste. hopefully it wont be, but then again i guess i wont tell the story about my friend who thought he would love kayaking so he bought a 4000$ kayak (when he could have spent like 800 on a beginners). That thing looks really cool sitting in his garage. I guess i shouldnt overgeneralize, but i just think too many times we are quick to part with hard earned money instead of trying something out, finding out whether we are going to stick with it, then making a plunge. im still not sold taht the rebel isnt an awesome camera. ithink it would have made a great starting point for this guy. just my opinion and sorry for the dissertation, but you struck a nerve. :)

hey i realize we are getting WAYY off target here, this is a camera forum right?You'll never get ahead of the Jones with that attitude.

smittymike19
14th of April 2005 (Thu), 12:59
You'll never get ahead of the Jones with that attitude.

:lol: excellent response.. really made me laugh :lol:

cfcRebel
14th of April 2005 (Thu), 14:16
To the original poster:

I am a slow reader, and books generally are not my good friends. But I love photography and want to learn. I know the fastest way to get up to speed is to read some good books. That means i have to make friends with books. I started with the 300D user manual, went over again & again. Then i bought a book that was recommended by some pros here. I think i learned faster now from the dicussions among these guys because i already gained some basic knowledge from the literatures. So I know what person A was asking, and what person B was referring to.
So read some photogaphy books or online tutorials definitely help bring u up to speed. Just wanna share.

Fer
14th of April 2005 (Thu), 15:04
Right on sister friend!!!! These guys make the biggest fuss over things, don'tcha think:lol: :lol: :lol:

AMEN! LOL

Dirty Shirt
15th of April 2005 (Fri), 09:10
Just to report back I have read the manual again! Although I may need to keep reading it until it is memorized!

jfrancho
15th of April 2005 (Fri), 09:22
This might help you translate that manual.
This book, along side the owners manual helped me understand how to use the camera: Digital Photography Pocket Guide, 2nd Edition (O'Reilly Digital Studio)

by Derrick Story. It's taken me 10,000 shots to even begin learning how to make a photograph.EDIT: Sorry, here is the link to amazon: http://www.amazon.com/exec/obidos/tg/detail/-/0596006276/103-2177233-7872669?%5Fencoding=UTF8&v=glance

sixshot
16th of April 2005 (Sat), 04:20
I have a EOS 300 and will be upgrading to the 20D shortly (ohhh I wish I knew how long shortly was!!), and I understand a fair amount about photography but find myself learning more all the time. This forum is about helping people learn more about photography, not about how to spend their money. I am sure when I fianlly get my 20D I too will ask some of these so called 'dumb' questions, then hopefully in the future I can help answer some of them myself to otherss.

I plan on buying the exposure book mentioned and think I'll even read the manual once now before I actually get the camera, a few more times afterwards! I think it is good to be able to explain in laymans terms the answers to hard - and easy - questions. I knew the answers to the questions here, but would have had difficulty explaining it myself. Well done to those who helped.

cc10d
16th of April 2005 (Sat), 09:34
No question is a dumb question. It is a desire for information, showing interest. Do not be put off by the minority. Ask and enjoy the appropriate responses.

Wishing you the best in your new adventures in SLR Photography.

jochyestrella
4th of May 2009 (Mon), 19:48
[quote=tim;491813]Stopping down a lens is just reducing the aperture. Say you have an F2.8 lens, stopping it down means reducing the site of the aperture - ie setting it to F4, F8, or smaller (higher F number is smaller aperture). "Stopping down" doesn't say by itself how much you're doing it. In Av mode this is done by twirling the dial beside the shutter button.

-------------------------------------------------------

close but not the most accurate definition of stopping down a lense, when you stop down a lense you have to remember that you affect DOF and the amount of light coming to your sensor, so when you have a fast lense lets say for example a 50mm f1.8 lense which by definition is a "Prime" or fast lense, by stopping the lense down you make the lense SLOWER to capture less light and to change the compression ratio of your scene so exposure and subject comes into sharp focus !

bluestring
4th of May 2009 (Mon), 19:51
I love these old topics.

xarqi
4th of May 2009 (Mon), 20:02
The concept of stopping down a lense besides increasing the f/stop is that the wider the aperture of the lense the fastest the lense is going to capture light coming to your sensor and the compression ratio of your image in relation to your lense max-min aperture, so you make it slower by stopping it down. so if you have a lense that is rated for f3.5-f4.0 which are the fastest ratings for the lense, then you stop this lense down or make it slower by going over the f4.0 aperture setting, this comes very usefull for example when you have an EF 50mm 1.8 lense, this a wide aperture lense and by means is a very fast lense, but at is widest paerture (f1.8) is very sharp at the center but the edges due to its compression, go and stop this lense fast aperture to a slower aperture and therefore DOF to make your image come sharper, less lightly and more contrasty !

:shock: