Spot metering - cause vignetting?

[Wendy Lilygreen]

I've got a new Canon and I was playing around with it and the metering modes. I noticed distinct vignetting when in spot mode, would this have been the cause or something else?

[dhbailey]

That looks like you have a hood on that isn't correct for your lens, and you are shooting wide enough that the hood is getting in the way.

The real test would be to put the camera on a tripod, shoot pictures of a fixed subject using different metering modes and leave everything else the same between the shots.

A single shot isn't enough to provide an accurate answer, in my opinion.

[SkipD]

Metering methods would not cause vignetting. You probably have something on the lens that is doing that. You probably have a filter or improperly sized lens hood that's getting in the way

[Wendy Lilygreen]

Nope - no hood and only a UV filter.

I'll try the tripod idea now.

Thanks chaps.

Wendy

[Andy_T]

Wendy,

what lens/filter are you using on which camera?
Without this information, we can only guess and offer you the 'standard' reasons for vignetting.

A UV filter can cause vignetting.
A reason why the vignetting might be more visible with spot metering might be that for whatever reason spot metering causes the camera to select a larger aperture ... and a larger aperture is a direct cause for more vignetting.

Best regards,
Andy

[Mike Panic]

your canon digital has a spot meter?

[PhotosGuy]

A reason why the vignetting might be more visible with spot metering might be that for whatever reason spot metering causes the camera to select a larger aperture ... and a larger aperture is a direct cause for more vignetting. What Andy is saying is that larger aperature number = smaller actual aperature size.
So f-16 will give you more DOF which means that the filter edges will be more in focus & tend to cause more vignetting than if you were at f-5.6.
This confusion in terms probably started about 2 days after they started putting f-stops on the lenses! ;-)

[Andy_T]

Photosguy,

No. :wink:
A larger aperture (smaller f-stop number,e.g. f/1.4) will give more vignetting than a smaller aperture
(larger f-stop number, e.g. f/8 ).

I linked an example:

http://www.vanwalree.com/optics/vignetting/wall.jpg
Optical vignetting with the Planar 50/1.4. Left: f/1.4. Right: f/5.6.
Read the whole article at: http://www.vanwalree.com/optics/vignetting.html

Best regards,
Andy

[CyberDyneSystems]

It would help if we knew what lens and what Camera..

With Spot metering we are in the 1 sereis,.. it could be a 1Ds which has a full frame sensor, making it far more prone to vignette than any other Canon digital...

Anywyas,. as mentioned above,. metering more would in no way effect vignette.

[PacAce]

Photosguy,

No. :wink:
A larger aperture (smaller f-stop number,e.g. f/1.4) will give more vignetting than a smaller aperture
(larger f-stop number, e.g. f/8 ).

I linked an example:

http://www.vanwalree.com/optics/vignetting/wall.jpg
Optical vignetting with the Planar 50/1.4. Left: f/1.4. Right: f/5.6.
Read the whole article at: http://www.vanwalree.com/optics/vignetting.html

Best regards,
Andy
That was an interesting read, Andy. Thanks for the link. :)

[PhotosGuy]

OK, when I said "So f-16 will give you more DOF which means that the filter edges will be more in focus & tend to cause more vignetting than if you were at f-5.6". F-16 will give a sharper, more apparent vignetting as shown in the "Mechanical vignetting" example in Andy's link. F-5.6 will show up as a wider, more diffuse vignetting, but it's questionable that it will be "more visible". If you shoot at f-1.4, you might not notice it at all.
England/U.S.: two countries separated by a common language. One might say the same thing about photgraphers.;)
Are we OK now? :D

[Wendy Lilygreen]

Hi - Its me.
The Camera is a 1DS MKII. It was set at 1/200sec.
Normal Program.
f5.6
Aperture value 5.7
ISO 200
300mm focal length.
Lens is a Sigma 28-300mm 3.5 - 6.3
UV Filter 62mm Digital Concepts Japan Optics.
Dogs are Jack Russells
Weather - grey and overcast.
No lens hood.

I have since tried it on all four metering modes this afternoon with no apparent vignetting. Sky still overcast (it is Wales after all). Subject this time was gravel and some flowers so it wasn't contrasty. The best exposure came from the evaluative mode.

Cheers
Wendy

[Andy_T]

Wendy,

nice camera :D

Now you'll most likely be flamed for committing the sacrilege of putting a Sigma hyperzoom instead of a Canon L lens on it :lol:

You might try a 'slim' filter to avoid vignetting at the wide end.

Best regards,
Andy

[Wendy Lilygreen]

Thanks Andy,
Before I get flamed (Ithought I would) I do have a Canon 75-300mm EF IS. (Hoya UV) 58mm but when I was using it last year on the 10d to do equestrian event photography I found that 75mm was too close sometimes.
I love the new camera, it's totally extravagant but I lost my Dad last year and as I'm now an orphan (a 50yr old orphan) I decided that the money was better in a camera than the bank! (i'd rather have my Dad tho!)

Cheers
Wendy

[Redbird_xo]

Thanks Andy,
Before I get flamed (Ithought I would) I do have a Canon 75-300mm EF IS. (Hoya UV) 58mm but when I was using it last year on the 10d to do equestrian event photography I found that 75mm was too close sometimes.
I love the new camera, it's totally extravagant but I lost my Dad last year and as I'm now an orphan (a 50yr old orphan) I decided that the money was better in a camera than the bank! (i'd rather have my Dad tho!)

Cheers
Wendy

Sorry to hear about the lost of a loved one.

Once you mentioned 75-300mm...people here would kindly remind you 70-200 f/4 L is a much better lens. Just a friendly reminder.

Seriously, your camera "deserves" better lenses.

P.S. I have the 75-300mm and don't own any L. :)

[CyberDyneSystems]

Wendy,
Sorry about your loss :(

No flame ;) BUT,. with the 1Ds MkII you are using a fll frame sensor,. one of the advantages of the smaller 1.6X sensor cameras was that with mediocre and lower quality lenses,. the "crop factor" means that one os only using the center of the optics,. Most of the light falloff and edge distortion is not in the image created.

With the 1Ds' full frame sensor you are using all of the lenses image.. out to the outer edges of the lens,. where typically distortion softeness and light falloff are at there worst.

In other words,. resolution detail aside,. you have a camera that will show a lenses faults much more than most Canon digitals will.

Add to that the fact that with 16MP your camera can out resolve many lenses.. and you have a mchine that absolutely demands the best glass you can put on it to get the cameras full potential.

Look to high quality primes to get the most of this camera ;)

[Wendy Lilygreen]

Hmm, thanks Redbird.
Why is the 70-200 a better lens? I appreciate what you say about the camera and totally agree.

Which do you think would be the better lens to sell? The Sigma 28 - 300? or the 75 - 300 Canon?
I have a Canon 17 - 35mm EF also but its a bit of a potch to swap and change all the time when I am in the show ring with horses.

Educate me please! I know that this Camera deserves tidy lenses - plus I may just have to visit America to buy them!

[R1 Kid]

Wendy sorry to hear about your dad. We have what is becoming a tradition at our house. I married 3 GREAT women just last month (my wife and her 2 girls). Their real dad died and every year on his birthday we send up ballons to heaven so he can have them for his birthday party. They are 2 and 4 years old and they enjoy this very much. Since I've taken up photography the next time his birthday comes around they will be using my camera to send up a picture of each of them.

I'm not sure why I'm sharing this with you exactly. Maybe there is a tie between you buying a camera and his passing?

God Bless, Jim

[GeForceFX]

Hmm, thanks Redbird.
Why is the 70-200 a better lens?


the 70-200 is a canon L lens (you recognize them by the red 'L' behind the F#)
these lenses are (mostly) better, faster en more expencive.


You find more than enough info about L-glass on this forum, most of us are already L-coholics :lol:

[RichardtheSane]

Hmm, thanks Redbird.
Why is the 70-200 a better lens? I appreciate what you say about the camera and totally agree.


The 70-200 F4L is much sharper than the 70-300IS - in fact it is regarded as one of the sharpest canon tele-zooms produced.

Sharpness is going to be very important to you now you have your new camera, all that resolution needs top quality glass in order to make your investment worthwhile.

In almost every case the camera is only as good as the glass you put on it.

[Wendy Lilygreen]

I agree, so which of my lenses should I sell then? (see previous entry)
What about below the 70mm?

PS
Wanna buy a lens?

[robertwgross]

Basically, it is not the filter that causes vignetting, but rather it is the filter ring that can cause it. If the filter ring is very thin, then it works perfectly, even on a wide angle lens. As the thickness increases (measured along the lens axis) it can possibly get in the way on a wide angle lens. The only problem with some thin ring filters is that many do not have any screw threads on the outside side, so you can't screw anything else into them on the front or else your vignetting problem will get even worse.

---Bob Gross---

[Andy_T]

You can check if what Bob said is really the reason for your problem by shooting the same image without and with the filter.

Use the lens on its widest aperture (AV mode)

As far as image quality is concerned, there can be considerable differences between different lenses.

Check out this article (http://www.e-fotografija.com/artman/publish/article_306.shtml), it gives an example by comparing shots of the Tamron 28-300, the Canon 70-200/2.8L and the Canon 70-300 DO.

You will notice that the difference in image quality is very pronounced at wide apertures and tends to diminish if you step down the lens (hence the saying "F 8 and you're there" :lol: )
But then, shooting conditions and your required effect for the photo often dictate that you use the lens wide open.

Best regards,
Andy

[PhotosGuy]

Andy, re your link:
Če strežnik ne najde željene strani, ste lahko vtipkali napačen URL naslov. Če menite, da ste naslov pravilno vtipkali (ali kliknili pravilni link) obvestite webmasterja strani ali pošljite mail na naslov webmaster@e-fotografija.com (webmaster@e-fotografija.com?SUBJECT=Ne%20najdem:%20http://www.e-fotografija.com/artman...ticle_306.shtml). V mailu obvezno navedite na katerih spletnih straneh se je napaka zgodila, če je mogoče tudi priložite link That say's it all, doesn't it? ;):D:D

[Andy_T]

:o

Thank you for commenting.
The link should work better now :wink:.

Best regards,
Andy

[Wendy Lilygreen]

Well to confuse matters even more there is a 35 - 350 usm L Canon for sale which I am thinking of! Please dont give me too much stick! With the weight of the 70-200 (wonderful tho it may be) I'd need to carry another lens with me, and change it. So the 35-350 is roughly the same weight (very heavy) and although it doesn't have IS I will probably use a monopod anyway. (Tripods and horse shows don't mix)

[Andy_T]

Wendy,

I think you won't go wrong with that lens. Although it's slower and not as sharp as the 24-70/70-200 combination, it has decent image quality and covers a great range on the 1Ds.

I've read many people swear by their 35-350 lenses.
How much is it?

Best regards,
Andy

[Tom W]

Read the whole article at: http://www.vanwalree.com/optics/vignetting.html

Best regards,
Andy

A most excellent and informative link - thanks, Andy.

[Andy_T]

Hehe, using wide angle converters on my G2, I did extensive research on vignetting :lol:

Best regards,
Andy

[Redbird_xo]

Hmm, thanks Redbird.
Why is the 70-200 a better lens? I appreciate what you say about the camera and totally agree.

Which do you think would be the better lens to sell? The Sigma 28 - 300? or the 75 - 300 Canon?
I have a Canon 17 - 35mm EF also but its a bit of a potch to swap and change all the time when I am in the show ring with horses.

Educate me please! I know that this Camera deserves tidy lenses - plus I may just have to visit America to buy them!

You are welcome! I don't own the Sigma 28-300mm. But the fact that it's a hyper zoom, it is more likely than not it won't produce "decent" images. Comparing the 28-300mm and 75-300mm, I tend to think the 75-300mm is a better of the two. From 17-300mm, I think you would be better off having at least two lenses to cover such range.

[Wendy Lilygreen]

In response to Andy I'm not sure how much it will be, I'm bidding for it on e-bay, I will let you know!

Wendy.

[Andy_T]

Wendy,

good luck with it :D !

Best regards,
Andy