re: DigCamera profiling
re: DigCamera profiling
- Subject: re: DigCamera profiling
- From: Dan Reid <email@hidden>
- Date: Fri, 23 Mar 2001 11:46:40 -0700
On Fri, 23 Mar 2001 07:59:55 -0500, Jack Bingham <email@hidden>
wrote:
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>
I can not speak for the Canon but have been wrestling with the D1 for
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some time. My experience is that a good profile works very well so long
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as you have a good gray balance. Yesterday I shot under fluorescent
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light using gelled strobes and attempted to use the custom gray balance
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arrangement which worked just short of not at all. I also shot a gray
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card on the first frame. In pshop I made an action to resize to 300 dpi,
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apply my camera profile and convert to adobe rgb, and apply a gray
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balance based on the gray card image. I attempted to do the same thing
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in Nikon Capture but it is not up to the task. The problem with this
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for you is you will need to edit the action for each new lighting
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arrangement. However, the results were very satisfactory, and in your
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case might eliminate some of the massive editing task otherwise
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required. And by the way for all of you out there, this guy lives in an
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incredibly beautiful country!
You have pretty much the right idea. But you want to apply you gray
balance BEFORE assigning your camera profile. Remember the first step in
implementing color management is process control. If you don't have any
process control you have no way to validate your conditions are the same as
when you built the profile. So white balance and grey balance (exposure)
before creating your camera profiles. This helps eliminate the variability
of lighting and exposure from being factored in the camera profile. Since
the MacBeth chart is metamerism free you will be profiling how the camera
responds to color not the lighting/exposure conditions.
In reference to the original post where the photographer is shooting in
clubs and low light situations you can still use the camera profile created
with white and gray balance. Why? Because we are describing the camera's
response to color not the lighting conditions.
Photographing in clubs with gelled lights and such is a perfect example
of why you *wouldn't* want to white/grey balance the shot because you want
to retain those creative decision and not nullify them by creating profiles
for each lighting situation. The camera profile created with white/grey
balance is still valid because we are describing what those RGB values mean
in Lab.
If your in a copy situation where you need to match the original or want
the closest match to subject mater then grey/white balance will pull the
image back in line to validate the camera profile. Also you can shoot the DC
chart open in Photoshop and create a white/grey balance adjustment and save
the levels/curves adjustment. Open your image apply the adjustment and then
assign your camera profile if the camera software does not offer (or does a
good job) for white/grey balancing.
I have used these techniques successfully for several installations
involving scanning and single capture cameras (including the D1).
--
Dan B. Reid
RENAISSANCE PHOTOGRAPHIC IMAGING
Color Imaging Solutions Provider
http://www.rpimaging.com | email@hidden
Toll Free: (866) RGB-CMYK [ 866-742-2695 ]
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