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Old Dec 21, 2004, 9:00 AM   #1
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Hi,

I've also noticed the chronic under exposure on my 20D using the built-in flash and wondered if other 20D owners would be game for an experiment.

The idea is to take a shot in standardized lighting (e.g., pitch black except for the flash), of a standardized target (e.g., a colour-card), from a standardized distance, with a standardized focal length, at standardized aperture & shutter speed.

The resulting images could then be processed through standardized way in DPP and posted for comparison.

Obviously, there would be some variation in lenses, but I'm not sure how much of an effect that would have. Opinions? Personally, I have an Canon 10-22(EF-S) and Tamron 28-200 XR at my disposal.

If anyone is game/has ideas on test parameters that will maximize the possiblity of participation, please post.

This might also help with testing the focus question (i.e., do camera and lens need to be calibrated to work together?).

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Old Dec 21, 2004, 11:55 AM   #2
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I had this problem with my 20d and sigma EF 500DG Super. Every shot was way underexposed.All I do now is up the flash bracketing by 2 full stops and hey presto, every flash shot is spot on.
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Old Dec 21, 2004, 3:23 PM   #3
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llama wrote:
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Hi,

I've also noticed the chronic under exposure on my 20D using the built-in flash...
Had the same experience with my 300D... Didn't want to do the Firmware hack so I just never used the built-in flash. I bought a 20D last week and noticed the same thing... Nice thing is the 20D has Flash Exposure Compensation (like the 10D...) I simply set the FEC to +2/3 and bingo I'm getting great exposures! Give it a whirl... :|

john
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Old Dec 21, 2004, 5:40 PM   #4
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Mr_Saginaw wrote:
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llama wrote:
Quote:
Hi,

I've also noticed the chronic under exposure on my 20D using the built-in flash...
Had the same experience with my 300D... Didn't want to do the Firmware hack so I just never used the built-in flash. I bought a 20D last week and noticed the same thing... Nice thing is the 20D has Flash Exposure Compensation (like the 10D...) I simply set the FEC to +2/3 and bingo I'm getting great exposures! Give it a whirl... :|

john
If you still have your EOS-300D, you can set FEC to +2/3 without installing the firmware hack, if your flash photos are consistently underexposed this much. Here is one free way:

http://revolution.cx/rcx/fecset.htm

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Old Dec 22, 2004, 2:55 PM   #5
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Hey Jim...

I tried that FEC program on my 300D today... WORKED GREAT! I set it to +2/3 and did some quick snapshots around the house... much better! Got it working just in time to sell it! LOL!

thanks!
john
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Old Dec 23, 2004, 1:20 AM   #6
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I recently purchased the Canon 580EX. Solved all of my underexposure problems I was having with my 300D and the Canon 420EX flash. Matter of fact I have a new problem now. When I am too close to light skinned peole, their clothes look perfect but skin is sometime too bright around cheeks and forehead. I ordered a stofen to solve this issue. I also tried the +2/3 setting witn 300D and 420ex and it was still inconsistent exposure espeacially in low light like night clubs.
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Old Dec 23, 2004, 11:01 AM   #7
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Hey minutephotos, I have the same kind of problem with my 20D and 580. What is a stofen and how would that help? Can you educate me? I was reading the other posts and was wondering about reducing the exposure. Any thoughts. Using flash is something I am pretty weak on.

Happy holidays- Merry Christmas
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Old Dec 23, 2004, 11:26 AM   #8
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I was going to suggest a soft-box, but you already know about that.
A stofen is a defuser that goes infront of the flash (mounts to it) that makes the flash less like a point source of light. It reduces harsh reflections.

I'm sure a quick google search will show you what they are. For example:
http://www.stofen.com/Store/Products.htm

Eric
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Old Dec 23, 2004, 4:37 PM   #9
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Hey minutephotos, what is a stofen; how does it work? I am pretty weak on using flash, but also have a 580 for my 20D. Skin tones on my camera also seem a little white or perhaps overexposed. My thoughts were to try to get less direct flash at close range [under 6'] and use bounce. With bounce though my shots seemed a little warm and underexposed. Haven't tried it yet but am thinking bounce with the white card up.

Maybe your stofen is what I need. Any thoughts?
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Old Dec 23, 2004, 5:38 PM   #10
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IMO a Lumiquest "Promax System" is much more flexible (and fold flat)
http://www.lumiquest.com/how.htm


... with the 'clear' cover on it acts like a Stofen:
http://www.lumiquest.com/lq931.htm
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