Home Products Download Order Contacts


Subject: Re: raw 3.1 professional custom profiles for highend digital cameras

Claude Jodoin here, Tech. Editor of Rangefinder, digital dude since 1986.

This is a terrific thread. Incident meters are highlight based, therefore, when calibrated to a particular sensor, they can provide the fastest, most accurate method of pulling the highlights to the rightmost positions without clipping. However, this varies with different RAW converters (slightly) and more so in in-camera Jepegs. This is what I teach in my CD's and lectures as an ultra-simplified method:

To calibrate, I set the camera to f/8 @ 1/125. The camera setting never moves but the meter is photographed in the same subject plane as a piece white seamless rolled up in a tube. This makes the test self documenting if you use a 70-200mm lens. With a single 5300 K studio light, I increase the power until I bump the reading of the incident meter by 0.1 stops, starting at a reading of 5.6.0. Then I take a shot of each. I keep increasing the flash power by 0.1 for each shot with a slider control or moving the light closer to the subject/meter. I do this for 21 frames, yielding images that read from f/5.6.0 to f/11. I aim for a target white point and read in the PS INFO Palette set to RGB and K. I try to hit a 240 value plus or minus 2 RGB. when looking at the file in photoshop. Since seamless paper is a matte white, I try not to let the peak value go too far below 5% (others may be more daring here). When I find this white number in PS, I can identify the meter reading in the image and know how many tenths of
stops I need to tweak to meter. I can then match the EI setting of the meter to the ISO setting of the camera. End of calibration.

This method, coupled with peak illuminace readings at the subject, has prevented me from ever blowing out whites in jepegs or in any RAW workflow for portraits or landscapes.

My current pet peeve about digital cameras is that, with the advent of fast rotary controls, why don't they give use 0.1 stop incemental aperture values? I got spoiled with 1/8 stop increments on my Foveon cameras, which used Canon L lenses. While they are at it, they could give us digital aperture displays to match our meters, instead of analog ones, which require further rounding off. This way we could have the same control in ambient lighting as we do in the studio. So, if you agree, how about you influential Canon dudes making some waves abou this one, eh?



View All Messages in adobe.photoshop.camera.raw

raw 3.1 professional custom profiles for highend digital cameras =>


Copyright 2006 WatermarkFactory.com. All Rights Reserved.