Further Discussion of B&W Conversions including Greg Gormans

imax

Thanks Andy for the information that is on Greg Gormans site. Also thanks for the information on Petteri's Pontifications All great stuff. I tried several this AM and I liked this one the best. Let me know what you think!


Original

Grayscale

Using Greg Gorman Black And White Conversion Techniques

Thanks for taking the time to look. Have a great day.

Joe

JimM

I like the conversion, but as for the image, I really want to see the eyes open.

imax

JimM wrote:

I like the conversion, but as for the image, I really want to see the eyes open.

So How Are These For Eyes

THe Original

And The Conversion

Thanks

Flyinggina

Let's see. I liked the first b&w conversion on the first photo (the Greg Gorman is too dark - at least on my screen), the open eyes in the second photo (the conversion is good too) but best of all the hair in the first. What looks best when you make a print?

Virginia

DavidTO

Part of Gorman's workflow is to use curves to control the density of the image. It looks like this is something that you should play with, as all of your conversions are too dense.

rutt

I'm thinking you B&W converted the first shot because the color didn't look too good. Really it's not hard to fix:





The idea is to reduce extreme yellows and magentas. If you use the eyedropper tool, you can measure the original and see that it's just too hot, particulary too yellow.

With this picture, as with many many portraits, it's hard to beat the just taking the green channel for a B&W conversion:



Once you get this far, you can use simple curves or highlight/shadow to bring adjust to show the detail you want a little better:

rutt

Why would you ever B&W convert this?



It's great the way it is. But OK, OK, just as an exercise:

Again I just took the green channel. Well, actually that's a lie. I blended in the blue channel only in the lightest parts of the image in order to recover the hair. I used the blend-if blending option to accomplish this:

flyingdutchie

I've been diddling around with L*a*b color for a bit and used it a couple of times to make B&W:

1. Convert to LAB
2. Make the A and B channel flat/horizontal. (For pure b&w the horizontal goes through the middle (0 or 50%))
3. Play with the Lightness channel to add/reduce contrast.
4. Sometimes I use Unsharp mask on the Lightness channel to increase local contrast (large radius, low amount)
5. Sharpen final image.



Is there any advantage to use LAB over RGB or vice versa?
-- Anton.

rutt

flyingdutchie wrote:

Is there any advantage to use LAB over RGB or vice versa?
-- Anton.

That question is like the first move in a really complex chess game. If you can, get Dan Margulis' Professional Photoshop and read the chapter Friend and Foe in Black and White. In short, the technique you outlined works, but loses the color information too early. For example, in my conversion of the woman, I used the blue channel for the hair and the green channel for most of the rest. Often the red information is very bad for faces but good for skys. Photoshop converts to LAB without knowing about faces and skys. But you do.

rutt

More specifically.


The conversion has resulted in a nice strong picture with deep blacks and pure whites, BUT technically it could be better. The policeman's shirt in the foreground has "plugged" (lost all shadow detail.) Look at the red and blue channels in RGB. I'll bet you can find some of that detail. Good B&W conversions exploit the detail in each channel. Blindly convert, either in LAB or just by converting to gray scale, and you lose the opportunity to do this.

flyingdutchie

rutt wrote:

More specifically.


The conversion has resulted in a nice strong picture with deep blacks and pure whites, BUT technically it could be better. The policeman's shirt in the foreground has "plugged" (lost all shadow detail.) Look at the red and blue channels in RGB. I'll bet you can find some of that detail. Good B&W conversions exploit the detail in each channel. Blindly convert, either in LAB or just by converting to gray scale, and you lose the opportunity to do this.

Actually, a lot of the details in the shirt were left, but got plugged when i increased the dynamic range. I just tried to do the RGB channel mixing, but i never got a nice contrasty picture - unless when i increase the dynamic range again. And that removed the details from the shirt again.
Short of brightning/darkening of only selective parts of the picture (much more work in PS:D ), how would i go about that?

If i understand LAB correctly, is the L channel not the channel that contains all the detail, where A and B contain only the colors? The shirt is just blue-ish (no details here) and the L channel contains the shadow details.... So, removing the A and B channel should not matter much, should it?

rutt

This is an extremely complex topic and we've hijacked this thread. I'll start a thread in the Digital Darkroom forum and ask the moderators to move the discussion of LAB and B&W conversion there. The color verson of the police wold be useful for that.

rutt

See here: http://www.dgrin.com/showthread.php?t=24374

flyingdutchie

rutt wrote:

This is an extremely complex topic and we've hijacked this thread. I'll start a thread in the Digital Darkroom forum and ask the moderators to move the discussion of LAB and B&W conversion there. The color verson of the police wold be useful for that.

You're right let's move it to that new thread.
For now, i reply here with the attachment of the color version.
The color version (shot in RAW), has been resized and slightly sharpened.