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blue_max
8th of July 2005 (Fri), 12:03
I have to shoot some folks tomorrow and just bought a 580ex on the recommendation of this very forum. Thanks - it looks a wonderful tool. I am from the school that thinks that flash lights up the whole scene, so am on a rather steep learning curve!

I would appreciate your tips on a fasttrack, surefire, never fails setting, that I can just dial in and never have to think about - at least until I have some time.

I have done some experimentation shooting various soft toys (needs must!) and am using the ETTL setting. I am getting quite slow shutter speeds and am fiddling with the main exposure plus or minus a half stop compensation and the same, but a bit more with the flash. I tried bouncing and direct (with a diffused plastic bowl of all things) and the direct and bowl seems best!

I can fiddle until I get it right, but is it going to be different for every scene or will the ETTL sort it out for me? I have a 10d which doesn't support the mkII version.

Also is using the fast sync going to cause me more problems that it solves - just shooting people seated and maybe a group or two. Does it cause blurring if people move?

I know I can rely on you guys to cut to the chase - I have read the manual, but it's not leaving me much time to put it into practice. I would really appreciate the benefit of your massed experience.

Thank you all - any tips would be most appreciated.

Graham

lostdoggy
8th of July 2005 (Fri), 12:36
If the camera is set to the Highest sync speed it should freeze most moving object. BTW what exactly do you mean by plastic bowl???

scottbergerphoto
8th of July 2005 (Fri), 12:54
Wow, you have me confused. ;)
You are throwing around alot of terms and ideas. Simplify things.
1. The camera metering is only for the ambient light.
2. Flash exposure is controlled by the camera body via ETTL or ETTLII and not by the aperture or shutter speed.
3. Flash pictures are really two exposures combined, the flash and the ambient light.
4. The effective shutter speed for the subject is the flash, about 1/10,000 sec. It will freeze most motion. You don't need a high shutter speed to freeze the subject. The flash does it for you.
5. Long shutter speeds result in blurry pictures due to the recording of ambient light after the flash pop, not the flash. If you do use a long exposure to get alot of ambient light rather then have a dark background, tell your subject to remain still even after the flash pop and use a tripod. This is done when taking pictures outside at night with street lights or such in the background.
6. Shutter speeds near the max sync speed, 1/200 (1/250) using a single flash, result in black backgrounds on most indoor exposures and aren't very pleasing.
7. The most relaible method of using flash for someone without much experience is to put the camera in Program Mode and the flash in ETTL. Program Mode will limit the slowest shutter speed to 1/60 sec. That will give you some ambient light in the background and it's fast enough prevent blur from the ambient light exposure. You can adjust FEC (not EC) to get the flash look you want.

blue_max
8th of July 2005 (Fri), 13:02
If the camera is set to the Highest sync speed it should freeze most moving object. BTW what exactly do you mean by plastic bowl???


I read (and that is where I didn't understand what I was reading), that at speeds above 1/200 the flash pulses on and off to extend the flash. It can result in blurred images apparently. I guess if it was an option, without any compromise, it would always be on.

I really do mean a plastic bowl. As you might eat your cereals out of!

Graham

scottbergerphoto
8th of July 2005 (Fri), 13:11
I read (and that is where I didn't understand what I was reading), that at speeds above 1/200 the flash pulses on and off to extend the flash. It can result in blurred images apparently. I guess if it was an option, without any compromise, it would always be on.

I really do mean a plastic bowl. As you might eat your cereals out of!

Graham
High Speed Sync is a term that is confusing to many people. It is the one exception to the rule that the flash is the effective shutter speed when using flash (1/10,000). In High Speed Sync, the flash pulses rapidly at low power to give a near contiuous beam of light. It is used when you have to use a shutter speed higher then the max sync speed of the camera and flash. In this situation, the shutter speed and not the flash, determines the motion stopping ability of your setup.
High speed sync is not for stopping action.
The maximum sync speed is not very fast and is not the maximum shutter speed of the camera. It is the fastest shutter speed at which the entire frame can be lit by the flash at normal flash power.

blue_max
8th of July 2005 (Fri), 13:14
Wow, you have me confused. ;)
You are throwing around alot of terms and ideas. Simplify things.
1. The camera metering is only for the ambient light.
2. Flash exposure is controlled by the camera body via ETTL or ETTLII and not by the aperture or shutter speed.
3. Flash pictures are really two exposures combined, the flash and the ambient light.
4. The effective shutter speed for the subject is the flash, about 1/10,000 sec. It will freeze most motion. You don't need a high shutter speed to freeze the subject. The flash does it for you.
5. Long shutter speeds result in blurry pictures due to ambient light, not flash. If you do use a long exposure to get some ambient light rather then have a dark background, tell your subject to remain still even after the flash pop.
6. The most relaible method of using flash for someone without much experience is to put the camera in Program Mode and the flash in ETTL. Program Mode will limit the slowest shutter speed to 1/60 sec. That will prevent blur from the ambient light exposure. For a more natural look, you can dial down the flash (FEC not EC).


Thank you Scott, you are right, too much info, but I felt I would try and get it all down so I didn't drag up issues later on.

To go through your points in the same fashion to keep it simple:
1. I get that, but does this have any impact on the ETTL programme ie does the flash compensate for the increase/reduction proportionately?
2. I can dial in an increase/decrease in the flash head and that has an effect. Should I be using the camera to do that in some way, and is it better to do that?
3. I am beginning to realise that now, after reading up on it.
4 and 5. So it's quite quick!
6. I tried that and it was not half as good as I got with aperture priority and fiddling with ambient light compensation and adjusting the flash by a half stop or so in ETTL mode.

I have done tests as I said and they look fine. My worry is that all this work will count for nothing tomorrow when I am in a different environment with different light and different subjects. If the settings will transfer without a hitch, I am worrying unnecessarily, but somehow I think I should be worried!

Graham

scottbergerphoto
8th of July 2005 (Fri), 13:20
Thank you Scott, you are right, too much info, but I felt I would try and get it all down so I didn't drag up issues later on.

To go through your points in the same fashion to keep it simple:
1. I get that, but does this have any impact on the ETTL programme ie does the flash compensate for the increase/reduction proportionately?
2. I can dial in an increase/decrease in the flash head and that has an effect. Should I be using the camera to do that in some way, and is it better to do that?
3. I am beginning to realise that now, after reading up on it.
4 and 5. So it's quite quick!
6. I tried that and it was not half as good as I got with aperture priority and fiddling with ambient light compensation and adjusting the flash by a half stop or so in ETTL mode.

I have done tests as I said and they look fine. My worry is that all this work will count for nothing tomorrow when I am in a different environment with different light and different subjects. If the settings will transfer without a hitch, I am worrying unnecessarily, but somehow I think I should be worried!

Graham
1. Any adjustments you make in shutter speed or aperture will be picked up by the preflash and adjusted for by ETTL, unless you exceed the capacity of the flash. Don't set f 22 and try to take a picture from 50 ft.
2. Only adjust FEC on the camera or the flash, not both.
6. Use what I suggested, Camera on P, Flash in ETTL. Take a test shot at your location. Use FEC +/- to adjust the flash exposure and EC +/- to adjust the background exposure.

blue_max
8th of July 2005 (Fri), 13:21
High Speed Sync is a term that is confusing to many people. It is the one exception to the rule that the flash is the effective shutter speed when using flash (1/10,000). In High Speed Sync, the flash pulses rapidly at low power to give a near contiuous beam of light. It is used when you have to use a shutter speed higher then the max sync speed of the camera and flash. In this situation, the shutter speed and not the flash, determines the motion stopping ability of your setup.
High speed sync is not for stopping action.
The maximum sync speed is not very fast and is not the maximum shutter speed of the camera. It is the fastest shutter speed at which the entire frame can be lit by the flash at normal flash power.

Thanks for the explanation again Scott, so is this for something like lighting up a building (or something static)?

Graham

scottbergerphoto
8th of July 2005 (Fri), 13:25
You would use HSS on a bright sunny day and your subject has plenty of light but some nasty shadows under the eyes that need a little light thrown in. So your shutter speeed could be a motion stopping 1/1000, but since the flash is functioning like a flashlight, it has no motion stopping power.

jrm
8th of July 2005 (Fri), 13:28
High Speed Sync is a term that is confusing to many people. It is the one exception to the rule that the flash is the effective shutter speed when using flash (1/10,000). In High Speed Sync, the flash pulses rapidly at low power to give a near contiuous beam of light. It is used when you have to use a shutter speed higher then the max sync speed of the camera and flash. In this situation, the shutter speed and not the flash, determines the motion stopping ability of your setup.
High speed sync is not for stopping action.
The maximum sync speed is not very fast and is not the maximum shutter speed of the camera. It is the fastest shutter speed at which the entire frame can be lit by the flash at normal flash power.

Scott,

Thanks for the explanation. There is one point where I am unclear.

You mention that in High Speed Sync, "the shutter speed and not the flash, determines the motion stopping ability of your setup."

Then you say "High speed sync is not for stopping action."

Aren't these two statements in contradiction? If not, please explain. Also, if not for stopping action, what would be the main uses of HS Sync?

Trying to understand the finer points of flash photography...

--Joe

blue_max
8th of July 2005 (Fri), 13:35
1. Any adjustments you make in shutter speed or aperture will be picked up by the preflash and adjusted for by ETTL, unless you exceed the capacity of the flash. Don't set f 22 and try to take a picture from 50 ft.
2. Only adjust FEC on the camera or the flash, not both.
6. Use what I suggested, Camera on P, Flash in ETTL. Take a test shot at your location. Use FEC +/- to adjust the flash exposure and EC +/- to adjust the background exposure.

Scott, you have been really helpful and I am very grateful. I am intending to go against my better judgement and go with your suggestion of using the P setting (point 6).

It's a bit of a leap of faith as I haven't got good results so far!

I won't have the benefit of a computer where I go, so I'm flying blind (or as good as the preview screen gets on a 10d). I need to establish a few things to give me the confidence to take this route.

A. Once I get the balance I am happy with, is it locked in or will it change if the light changes during the course of the day.
B. Is bouncing the flash off the ceiling better that using a diffuser (bowl!) for portraits.

Sorry it's twenty questions, but thanks if you can spare the time to answer.

Graham

scottbergerphoto
8th of July 2005 (Fri), 13:36
What's the fastest shutter speed of your camera? 1/4,000-1/8,000
What's the speed of a flash? 1/10,000
When you use regular flash and the flash is the primary light source, that 1/10,000 nails the subject. The shutter is grabbing some ambient light.
In HSS, the flash is an almost continuous light source (weak at that), so the shutter speed is the limiting factor stopping action. You might use HSS to add some fill light to a picture taken with a fast shutter speed in good ambient light, but the flash is not freezing the action, nor would it provide enough light to light the subject as the main lighting. So don't expect to freeze someone moving in a dark room by upping the shutter speed and using HSS.

scottbergerphoto
8th of July 2005 (Fri), 13:40
Scott, you have been really helpful and I am very grateful. I am intending to go against my better judgement and go with your suggestion of using the P setting (point 6).

It's a bit of a leap of faith as I haven't got good results so far!

I won't have the benefit of a computer where I go, so I'm flying blind (or as good as the preview screen gets on a 10d). I need to establish a few things to give me the confidence to take this route.

A. Once I get the balance I am happy with, is it locked in or will it change if the light changes during the course of the day.
B. Is bouncing the flash off the ceiling better that using a diffuser (bowl!) for portraits.

Sorry it's twenty questions, but thanks if you can spare the time to answer.

Graham
Each time you change rooms and ambient lighting, you will need to readjust.
Whether you bounce or use a diffuser is a matter of personal preference and the availability of something white to bounce off of. I like the Lumiquest Pocket Bouncer.

blue_max
8th of July 2005 (Fri), 13:46
Thank you Scott, you have been extremely helpful and I am very grateful for your time. It is much appreciated. I have certainly learned something and hope it has been useful to the forum.

I'll let you know how I get on!

Best.

Graham

scottbergerphoto
8th of July 2005 (Fri), 13:48
I'm glad it was helpful. Try to enjoy yourself!

blue_max
8th of July 2005 (Fri), 14:11
I'm glad it was helpful. Try to enjoy yourself!

It will be a whole lot more enjoyable if the photos come out good. Just a tad embarrasing if they don't. :lol:

I owe you one Scott. You have been very generous with your time and sharing your experience.

Thank you, once again.

Graham

RTMiller
8th of July 2005 (Fri), 14:52
I love reading Scott's answers to flash photography questions. It is a difficult subject to wrap your head around and Scott's explanations always help make it more understandable.

Curtis N
8th of July 2005 (Fri), 15:21
I love reading Scott's answers to flash photography questions.I second that.

I wish Canon would hire Scott to write their instruction manuals. Then maybe they would be useful!

robertwgross
8th of July 2005 (Fri), 17:20
I wish Canon would hire Scott to write their instruction manuals.

Scott is not fluent in Japanese English.

---Bob Gross---

SidW
8th of July 2005 (Fri), 18:40
Originally posted by robertwgross

Scott is not fluent in Japanese English

Bit below the belt, but oh so true.:lol:

I'm still trying to figure out what "imagination adjustment" means in the manual for my monitor.

SidW
8th of July 2005 (Fri), 18:44
Forget to mention, I have learned more from Scott in a couple of weeks than I have from reading the manual and trying different things myself.
Thanks Scott.

Sid

PhotosGuy
9th of July 2005 (Sat), 08:40
I would appreciate your tips on a fasttrack, surefire, never fails setting, that I can just dial in and never have to think about - at least until I have some time. I'm chimimg in late 'cause I didn't want to confuse the issue & I don't have the 580ex, so can't comment on the auto settings.
If anyone is willing to shoot on "M", there's a simple formula to compute relative flash exposure here...
http://photography-on-the.net/forum/showthread.php?t=66353

ska60te
9th of July 2005 (Sat), 11:02
Hi Graham, Scott's advice is right on,I have the 580EX also and for a "base line" Try this ISO 400,Manual mode on camera body,f-8.0,125sec.,ETTL on your flash +2,I am assuming you are indoors and remember this is a "baseline"setting.High speed flash sync also. Os