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Old Apr 30, 2010, 10:59 AM   #21
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That depends on what you want to show. ;-)

If you want to show how a given camera works in a given lighting condition without the camera's JPEG algorithms entering into the equation, you'd need to do a linear raw conversion using a product that isn't applying curves, multipliers and noise reduction. That rules out many commercial applications like Adobe's products (because even if you set everything to the lowest settings, it's still applying curves, some amount of NR, etc.). Off is not off with those types of products. So, you'd want to use something like dcraw.c from command line specifying a linear conversion (or at least use similar products based on dcraw.c code).

If you want to show how a camera processes the raw data into JPEG, then different camera settings will impact results.

But, regardless of whether you're using linear conversions (not applying any tone curves or RGB multipliers to correct for lighting temperature), different cameras are going to work better in some lighting conditions versus others, because of differences in their Bayer Filter arrays (some may pass light for some colors better at some kelvin lighting temperatures compared to others, with big differences in response curves in different lighting).

IOW, one camera may work better in incandescent lighting, and another may work better in daylight lighting, because different types of multipliers may be needed to correct for lighting temperature differences in order to give you a color corrected image during the processing to jpeg step. So, you can only compare how cameras work in specific conditions (especially where lighting temperature is concerned). Most review sites use simulated daylight lighting anymore when showing noise differences. But, that's not necessarily a good way to show how cameras compare (since you'd be more likely to use higher ISO speeds in artificial lighting). ;-)
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Old Apr 30, 2010, 11:05 AM   #22
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How about just doing a factory reset on each camera before you do your test?

See page 280 of the K-x Operating Manual, and page 136 of the T1i Operating Manual.

Of course, your brother-in-law (or whoever's K-x you're borrowing) may not thank you for it.
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Old Apr 30, 2010, 11:09 AM   #23
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Hate to say it RAW is not an option, lol. I have not even tried to use the raw converter in aperture 3 yet.

Also I want to shoot jpeg as new users use that first before going to RAW shooting. So I want to give them a good idea of out the camera performance without editing.

But honestly if the more advance users want some RAW sample. I will shoot it, and figure out the converter in aperture.
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Old Apr 30, 2010, 11:12 AM   #24
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How about just doing a factory reset on each camera before you do your test?

See page 280 of the K-x Operating Manual, and page 136 of the T1i Operating Manual.

Of course, your brother-in-law (or whoever's K-x you're borrowing) may not thank you for it.

That is what I plan to do TCav. But the picture style will default to standard on the canon and I think bright on the pentax. Not sure that will give me the same shutter speeds in aperture mode.
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Old Apr 30, 2010, 11:13 AM   #25
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That would be one way to do it (set everything to factory defaults to show how the JPEG images compare). But, in the case of the conditions the cameras are being used in, it appears to my eyes that Auto WB differences are probably accounting for a lot of what you see in the end result. So, that doesn't show what the cameras are capable of in those conditions. IOW, I'd probably use a specific kelvin temperature for both cameras' white balance, unless you just want to show Auto WB results. Since most cameras tend to do better with their Auto WB algorithms in simulated daylight lighting, that's probably one reason many review sites compare cameras that way. But, that really doesn't tell you how a given camera is going to perform in other lighting conditions (once you correct images so they'll have more accurate colors in a given lighting).
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Old Apr 30, 2010, 11:18 AM   #26
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But, if I were going to try and show how noise compares from different cameras at higher ISO speeds, I'd probably pick almost anything except for a night cityscape scene (where you're better off keeping ISO speeds set low and using a tripod, as in your long exposure images). ;-)

IOW, I'd find conditions that users would be more likely to use higher ISO speeds in to show how cameras compare.
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Old Apr 30, 2010, 11:21 AM   #27
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I am not sure I want to use a custom WB or k level, but if you think it will help I will drag out the white balance card. As the canon do not have a kelvin range. Or I have not figure out how to use it. As I do custom WB most of the time or use tungsten at 3000k. I was trying to use the auto as again newer user will be using that feature first till they get more advance.
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Old Apr 30, 2010, 11:22 AM   #28
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But, if I were going to try and show how noise compares from different cameras at higher ISO speeds, I'd probably pick almost anything except for a night cityscape scene (where you're better off keeping ISO speeds set low and using a tripod, as in your long exposure images). ;-)

IOW, I'd find conditions that users would be more likely to use higher ISO speeds in to show how cameras compare.
I was thinking about a night shot of a lite billboard
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Old Apr 30, 2010, 11:22 AM   #29
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Of course, that probably depends on the user, too. But, I'd probably use typical indoor scenes in tungsten lighting to show how noise compares from cameras at higher ISO speeds, setting white balance to match the lighting (as you'd want to do that for best results with most cameras in artificial lighting), as that's probably the most likely type of lighting that users would want to use higher ISO speeds in.
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Old Apr 30, 2010, 11:34 AM   #30
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I'd go with the Tungsten setting instead of the gray card. The light where you're standing may be different from the light on the other side of the river.
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