Getting more contrast on B&W conversion

Jeff Klofft

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I'm converting some images that I have from color to B&W. I tried a number of different methods (taking the lightness channel in LAB mode, using the channel mixer, and desaturating), but I always end up with a rather flat image. I've tried adjusting the curves a bit, but even that is not delivering the result that I'm looking for. Any suggestions for bumping up the contrast? Thanks.

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Jeff
Member said:
 
check out (and search) the retouching forum here. lots of good ideas and people there. there are a lot of ways to do the conversion...
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codfish
 
Good darkroom printers don't use actions or channel mixing....they use dodging and burning — I'll argue that dodging and burning gives you way more control over your shadow and highlight detail, your contrast, and gives you the ability to control depth and emphasize subject matter mo' better than any of the cuve or channel techniques....they're ok to start with, but I find i get better results when I use them to generate a very low/middle contrast image and build the contrast and tonalities with dodge and burn.
 
why does photoshop burn my images with 'grey'only???....works well with B&W, but makes color look a bit bad....
Good darkroom printers don't use actions or channel mixing....they
use dodging and burning — I'll argue that dodging and burning gives
you way more control over your shadow and highlight detail, your
contrast, and gives you the ability to control depth and emphasize
subject matter mo' better than any of the cuve or channel
techniques....they're ok to start with, but I find i get better
results when I use them to generate a very low/middle contrast
image and build the contrast and tonalities with dodge and burn.
--
...........everyone is somebody else's weirdo......
 
Jeff,

This shot looks good on my monitor. But how do you propose to print it ?
BW printing from digital appears to be a dismal area.
1. On line printers use color papers which leave color casts
2. Epson printers generally leave color casts or take endless tweaking

3. The new HP 7960 can do slightly warm black and white but leaves roller scuff marks on the prints and has virtually no documentation for use with
Photoshop
4. Custom labs can do the job but are very $$
Please tell me if you have any ideas as I am in a similar situation.

Stuart
 
Jeff,
I hope you do not mind that I used one of your images to
show you how I've been taught to make B&W converisions.

Open original file, duplicate it
open dupe file & copy red channel and
paste it on to the original
do the same with the green channel
name both.
Convert the dupe file to LAB
and paste the lightness channel
on to the original file
use the opacity of each layer
to adjust your converion.

best,

Mel



here's a before and after


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http://www.melhill.com
 
I have had no problems with colour casts from my online printer when printing B&W (Uses Fuji Crystal archive colour paper)

Instructions from Photobox - a UK online printer are to "desaturate" the image in RGB rather than convert to greyscale.
 
It doesn't burn them with gray...it darkens all the colors equally....to see how it works, put a color sampler (eyedropper) down on the area you want to burn and watch the info pallette as you burn....you can, of course, just burn in specific channels to modify color....but overall, it's probably best to dodge or burn areas that are not critical for color (sky, shadow, foregrounds work pretty well....flesh tones do not!).
 
There are places out there that specialize in b+w prints....the guy I'm familiar with is http://www.lotuscolor.net (for those in the San Francisco area). He uses MIS quad inks on (believe it or not) an epson 3000....you can order quadtone inks from companies such as Lyson, they replace your 'full' gamut color cartridges with a black and 3 grays (custom profiles available). The results are stunning. Printing on a coated art paper (like smooth arches printmaking paper) the effect if very similar to a print on bromide paper (nice inky, flat blacks) and soft grays....
 
Use MIS ultratone 2 carbon pigment inks (available in cartridges and CIS).

The improvement over color inks is incredible. Absolutely no colour casts or metamerism, look identical under daylight, tungsten, flourescent, no split toning effects and the images have that 'etched in silver' look and deep blacks of a strong glossy chemical print.

Superb! I just can't get over how good they look and you can vary the tone very subtly from a cool look to a slightly warm look by just using the colour controls in the print driver.

And amazingly, ordering from the US, delivered to here in London, they cost LESS than standard Epson inks bought from Jessops a mile down the road from where I live.

Can you guess I'm enthusiastic about these inks....?
 
greydarrah wrote:

I think that you can get fine contrast and depth to an image using channel mixing. I ususally start with something like Red: 60, Green: 20, Blue: 40 and run the Constant up or down to make give the image more impact.


Take this one step further with this neat little trick...

When you shoot black & white film, what do you put on the front of the lens to alter tone and contrast? Filters. So why not do the same in the computer.

After you do the above with a Channel Mix adjustment layer above your color image, you create a Hue Sat adjustment layer between the color layer and the Chan/Mix layer thus creating a color filter. All you have to do now is vary the Hue slider (filter color) until you see the the image you like. You can also adjust saturation to vary the intensity of your new color filter.

By the way, I believe that the above Channel Mixer adjustment layer numbers are the same as if you simply converted to grey scale and are thus a good starting point. The filter trick just gives you instant access to a pumped up image.

Cheers, MARC

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Marc Longwood
Sacramento / California / USA
 
Hi Jeff,

You've gotten some great advice so far -- I'll add a few things I've found helpful. Getting a punchy look like we used to get in the darkroom is a trick. I start with a channels conversion -- dropping the red to around 30, and then mixing in some green and blue to taste, and finally, readjusting the red.

Then I do curves adjustment to punch up the blacks. You can also do this with the levels control, or with the Shadow/Highlights control in CS. But the point is to make sure your blacks are at max.

I printed darkroom black and white for years, and typically used Selinium toning to punch up the blacks. It also gave a slight warm tone that I found pleasing, but I know is out of vogue today, despite it's prominent place in photographic history. Today, most people like their black and whites to have a very cold tone. But I think mixing in a little color makes the prints pop a bit more. Finally, be aware that many of the great black and white printers manipulated their work heavily, using tons of dodging, burning, toning, and other effects to get that "look." Getting some of the how-to darkroom books from the 60s and 70s will help a lot.

Anyway, here are some examples of conversions I have done:










--

Regards,
Paul
http://www.pbase.com/pgrupp
 
I don't want to dis channel mixin and curves -- I always start there, and then finish with dodging and burning. Also, the shadow/highlight control, used VERY judiciously, can help a lot too.
Good darkroom printers don't use actions or channel mixing....they
use dodging and burning — I'll argue that dodging and burning gives
you way more control over your shadow and highlight detail, your
contrast, and gives you the ability to control depth and emphasize
subject matter mo' better than any of the cuve or channel
techniques....they're ok to start with, but I find i get better
results when I use them to generate a very low/middle contrast
image and build the contrast and tonalities with dodge and burn.
--

Regards,
Paul
http://www.pbase.com/pgrupp
 

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