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Old Jun 8, 2004, 3:36 AM   #1
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Yes,some are darker and some are lighter ...

indoors shots ,why does rebel take different shots at the same condition,same frame and same zoom rate?WhenI shota subject from the same distance with thesame settings it shots different lighting photos.some of themare darkerand some of them are lighter.??What is the reasonofthis difference?Multi point zoom?I cant shoot a subject fix lighting rate.when Ilook at the photos infowhich I took,thef number and shutter speeds and isoare the same but photosseem in different lighting.I think flash exposure can not be set correctly by camera.Sometimes it s strong and sometimes poor.Must the rebel set the flash exposure more correctly depending the condition?
and another issue,when I shot my room 18 mm wide zoom,it shots a lighter photo but at the same room when I make zoom 24or 28 mm,it just shots darker photos.Why does not rebeladjust the correct settings?My old s45 is better at this kind of indoors shotings.Do I have to take 3 or 4 shot to find the correct photo indoors?What will I say to my objects "oh sorry, dont move please,the first shotwas not good so I'll take a second one or third one or...:?:evil:


How should I do the settings?How do you shot with your rebel indoors photos?

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Old Jun 8, 2004, 8:46 AM   #2
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If you want to save yourself a lot of frustration with the DRebel and flash exposure, set your camera meter to M, adjust your shutter speed to 1/60-1/100 and set your aperture to around f/5.6-f/8 (don't worry that you're not metered correctly for the ambient light...trust ETTL), turn your flash on (are you using external flash? --I never use the onboard flash, so I'm not sure about this), and take the picture. ETTL will automatically provide light based on its own sensor independently of the cameras metering. Experiment with this mode and see what works best for you. I have found that any of the automatic modes do not do well for indoor flash. Outdoors, Av mode works well for fill flash.

Canon's ETTL is different from other manufacturer's TTL flash systems. There is a paper out that explains it in detail and is quite thorough, albeit long and sometimes difficult to understand at first read. http://photonotes.org/articles/eos-flash/
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Old Jun 8, 2004, 9:20 AM   #3
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Even if you set the camera to manual the E-TTL flash is still metered by the camera (try to put a polarizer in front of the lens to check this out!).

What you are running into is the evaluative metering at work: the camera evaluates the scene with the pre-flash (based on which AF point(s) it has selected) and exposes the scene based on "its evaluation" the second flash pulse come around. There's two ways around this:

1. Pressed the * in the flash mode it becomes FEL (Flash Exposure Lock) and only use the central ~10% area for metering.

2. Set the external flash on Manual as well (only on 550EX) and use the ratio to control power...




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another issue,when I shot my room 18 mm wide zoom,it shots a lighter photo but at the same room when I make zoom 24 or 28 mm, it just shots darker photos.
Did you release the shutter when you zoomed or kept the shutter 1/2 pressed? This is a variable aperture lens, ie the aperture get smaller as you zoom in... :idea:
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Old Jun 8, 2004, 10:58 AM   #4
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NHL wrote:
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Even if you set the camera to manual the E-TTL flash is still metered by the camera (try to put a polarizer in front of the lens to check this out!).

My point was that he shouldn't worry about trying to meter for the ambient light, which is what the auto modes tend to try to do. P mode just doesn't cut it because it choses the settings prior to flash exposure (which are generally wide open aperture and 1/60 sec shutter) and Av and Tv modes consider the flash as fill flash. By being in M mode, the flash brain takes over and determines the exposure needed while allowing the operator to choose his aperture and shutter speed provided he stays within the realm of the guide number rating of the flash.

I'll confess that I don't know the details of how it works, and to be honest, I don't even care. I'm just interested in taking good pictures and found that this method works best.

One of the niceties of digital film is that you can experiment with various methods of doing things without wasting $$$ in processing costs like you did with film. My suggestion to new SLR owners is to go out and experiment with their camera and pay attention to what is going on when they do things. It's all well and good to ask questions in a forum such as this, but you'll learn a lot more by taking that information gathered from various sources and experimenting. Of course, there are plenty of people that are techno-oriented that have to dissect each variance. Nothing against that way of learning, I just learn better by doing.
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Old Jun 8, 2004, 4:09 PM   #5
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OHenry

Putting the camera on manual is the right thing to do since you gain more control, but this is why I mentioned putting the camera on manual doesn't help:
Quote:
I cant shoot a subject fix lighting rate.when I look at the photos info which I took,the f number and shutter speeds and iso are the same but photos seem in different lighting.
ie the f-number and the shutter speed are fixed (just like if you were to put the camera on manual), but the exposures still vary because of the various "evaluative" metering done by the camera, which is not fixed and variable by the flash output through E-TTL -> some are darker and some are lighter!

You can forced the camera to be "non-evaluative" by using * (FEL) which just meter the central area. :idea:
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Old Jun 8, 2004, 4:14 PM   #6
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thanks for the replys and suggestions.I'll try various of them.I love (want to love at least) my Drebel and dont want to sell it because of some frustrations
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Old Jun 8, 2004, 5:06 PM   #7
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civil

This is exactly your same problem, but with flash instead:
http://www.stevesforums.com/forums/v...11&forum_id=37
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Old Jun 8, 2004, 6:19 PM   #8
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NHL yazd─▒:
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civil

This is exactly your same problem, but with flash instead:
http://www.stevesforums.com/forums/v...mp;forum_id=37
it's really exactly the same problem.I cant understand this; Why the rebel owners dont mention about this problem?I think this is a special problem for all therebels.My S45 is better at this point.Unfortunately,I really disapointed with the rebel.Now,what should I do?I wish I bought D70 instead of rebel :sad:

I will sell it :evil:
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Old Jun 8, 2004, 7:31 PM   #9
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Flash photographywith the Rebel isnot a problem, it's just different from what you're used to. Once you learn it, you can take wonderful pictures.
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Old Jun 8, 2004, 11:08 PM   #10
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civil wrote:
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... I think this is a special problem for all the rebels. My S45 is better at this point. Unfortunately, I really disapointed with the rebel. Now,what should I do?
... IMO nothing, and it's not just the DRebel but my 10D as well!

I agree with Ohenry that photography with the Rebel is not a problem, it's just different from what you're used to. Once you learn it, you can take wonderful pictures:

1. Your S45 metering is probably not as sophisticated as the DRebel, ie it's probably center-weighted and wouldn't work in difficult lighting situation like bright background or bias its exposure on the subject you try to focus against a bright sun for example...

2. You can make the DRebel behave like your S45 by programming the AF point to use the center one only, ie it will then bias toward the center area only!

3. Instantly overide the camera through the * button (AE lock or FEL) depending on normal or flash mode.

4. Canon has finally realized this issue and they already remedied it on the 1Ds by also factoring the distance info from the lens into the flash computation (E-TTL 2). BTW this in not new, it was originally implemented on Minolta with ADI (Advance Distance Integration), follow by Nikon... and Canon have resisted against this switch for a very very lo..o..ong time (some Canon older EF lenses don't even have the distance encoding in them.)

From: http://photonotes.org/articles/eos-flash/#digital
"Unfortunately, E-TTL has been a particular problem for digital EOS users. Many users report serious problems with wildly varying exposure when using an E-TTL flash unit with their Canon DSLRs, particularly the D30 and D60. Some of these problems stem from the users focussing and recomposing and failing to use the flash exposure lock (FEL) feature, which sets the wrong area around which the flash will meter. But many problems can't be blamed on this. The main problem appears to stem from the way in which E-TTL on these bodies biases flash exposure heavily to the focus point. For more information please consult the section on E-TTL flash metering patterns. For this reason some digital EOS users have given up on E-TTL and gone back to the old-style autoflash units. Others routinely set their lens to manual focus once focus has been achieved, since the camera uses a centre-weighted average metering pattern for flash metering when in manual focus."
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