White or Grey

Well, interesting topic.

1. set exposure
2. set white balance


I use a photovision target card. white/grey/ black shows me where the exposure should be in the histogram, then I set custom wb off of it. easy peasy.

dmward wrote in post #18349907
The Kodak gray cards that predate digital photography are not color neutral. They are poor white balance references.

So who is still using any of those?

And they actually were always good color balance references as gray reference targets in the scene. You bought a particular batch of color film, photographed a Kodak gray card, examined the color of the card in the resulting test images and determined the necessary correcting gel filter pack. Worked just fine for film and can be used the same way in digital. I generally shoot RAW and use a gray card target snap to color balance in post.

What the pre-digital Kodak cards were not optimum for was digital camera custom white balancing under incomplete-spectrum lighting.

Pre-digital Kodak cards were fine for pre-digital color balancing. They weren't fine for digital custom white balancing, so Kodak fixed them.

RDKirk wrote in post #18349964
So who is still using any of those?

And they actually were always good color balance references as gray reference targets in the scene. You bought a particular batch of color film, photographed a Kodak gray card, examined the color of the card in the resulting test images and determined the necessary correcting gel filter pack. Worked just fine for film and can be used the same way in digital. I generally shoot RAW and use a gray card target snap to color balance in post.

What the pre-digital Kodak cards were not optimum for was digital camera custom white balancing under incomplete-spectrum lighting.

Pre-digital Kodak cards were fine for pre-digital color balancing. They weren't fine for digital custom white balancing, so Kodak fixed them.

I've got some well stored Kodak cards. Sometime (never!) - I may set up a digital comparison with the WhiBal card, Kodak Card, Color Checker Passport and a white sheet... I'll bet I need to recalibrate my CRT too!!

About the pre-digital MacBeth color charts -- you can see quite a difference between these and ones used for today's digital world.

What differences have you seen in the MacBeth, pre-digital vs. digital?

Wilt wrote in post #18349983
What differences have you seen in the MacBeth, pre-digital vs. digital?

I'll take a pic and display both (unscientific). This weekend. Got jury duty this week...

Some info

http://www.babelcolor.​com …acbeth%20ColorC​hecker.pdf

dmward wrote in post #18349908
I think there is probably a whole pre-press profession that would challenge that statement.
Perfect/exact are relative terms. I know from experience that using a color checker for reference I can produce digital images of art work and products that are visually identical.

Agreed. Pre press AND press operators.


I used to scan color prints, color correct them, convert to CMYK, buy matchprints, correct any mistakes, put them in the catalog layout, and then go to the print house to proof them as they came off the press. Color reproduction was 100 percent my responsibility.

The product I'm referring to here was typically western boots that came in a bazillion different blacks and browns ... dfferent finishes etc.

Depending on who was dialing in the press, I knew if it was going to be a long or short day. Our results were spectacular, on the level that few would understand without witnessing the entire operation.

Today it is much easier, but something still best left to a team of professionals.

PhotosGuy wrote in post #18349937
It's amazing that we get as close as we do. Considering we start with pixels captured by a camera, viewed as pixels on a RGB monitor, converted to CMYK, & then printed with dyes & pigments on varying grades of paper, isn't it?

Absolutely.

Going back to OP's original question, in my opinion both will work just fine, but grey will give more latitude as white is easier to blow out (overexpose). In a pinch, if you forget to use either, whites of subject's eyes will bring you close enough (assuming its a portrait shot)

starlights wrote in post #18381541
Going back to OP's original question, in my opinion both will work just fine, but grey will give more latitude as white is easier to blow out (overexpose). In a pinch, if you forget to use either, whites of subject's eyes will bring you close enough (assuming its a portrait shot)

It should be remembered that if one attempts to fill the frame with the target surface, the meter suggests an exposure which renders that target as 'mid-tone', That renders a gray target as mid-tone (gray) or a white target as mid-tone (gray)...so there is zero danger of blowing out a white target.
Either exposure works just fine as a basis for Custom WB in-camera, or as a sample for eyedropper WB setting in postprocessing.

Wilt wrote in post #18381836
It should be remembered that if one attempts to fill the frame with the target surface, the meter suggests an exposure which renders that target as 'mid-tone', That renders a gray target as mid-tone (gray) or a white target as mid-tone (gray)...so there is zero danger of blowing out a white target.
Either exposure works just fine as a basis for Custom WB in-camera, or as a sample for eyedropper WB setting in postprocessing.

That's presuming you've set your exposure by that tone instead of having set exposure by some other method and are only doing a custom white balance at that point.

RDKirk wrote in post #18382216
That's presuming you've set your exposure by that tone instead of having set exposure by some other method and are only doing a custom white balance at that point.

...which is precisely why I described "if one attempts to fill the frame with the target surface, the meter suggests an exposure which renders that target as 'mid-tone',"

Wilt wrote in post #18382274
...which is precisely why I described "if one attempts to fill the frame with the target surface, the meter suggests an exposure which renders that target as 'mid-tone',"

Metering isn't part of the custom light balancing task.

It IS how you get both 18% gray target or the 90% white target to be captured mid-tone so that none of the color channels have gone into clipping, and hurting WB as a result!

I normally set exposure first then the white balance.

I'll use a WhiBal card or a colorchecker passport.