Conversion to B&W....

Tim Kirkwood · December 10, 2004

Wondering what the best way is to convert to B&W in PS 7?

Thanks guys

Tim

gus · December 10, 2004

Image ...mode...grey scale in PS 6 if that is the same.

Tim Kirkwood · December 10, 2004

Humungus wrote:

Image ...mode...grey scale in PS 6 if that is the same.

I tried that and it seemed ok but I have once seen some lengthy threads about these in depth methods for conversion. Differant layers and monochrome,ect....who knows what else lol

Just wonderin

Tim

Andy · December 10, 2004

there's a week's worth of reading on bw techniques here

good luck!

pathfinder · December 10, 2004

Tim Kirkwood wrote:

Wondering what the best way is to convert to B&W in PS 7?

Thanks guys

Tim

If you rummage through the Hall of Wisodm thread here on Dgrin yoiu wil find several threads and at least 5 or 6 different ways to convert RGB to B&W.

I prefer the method promoted by Greg Gorham - you can find it at this URL http://www.gormanphotography.com/gorman.html when you click on the B&W conversion tutorial PDF button.

Tim Kirkwood · December 10, 2004

andy wrote:

there's a week's worth of reading on bw techniques here

good luck!

Thanks Andy I will have a look.

Watching you supply resources to posters makes me believe that your "favorites" folder is probally stuffed full:D

Tim

wxwax · December 12, 2004

pathfinder wrote:

If you rummage through the Hall of Wisodm thread here on Dgrin yoiu wil find several threads and at least 5 or 6 different ways to convert RGB to B&W.

I prefer the method promoted by Greg Gorham - you can find it at this URL http://www.gormanphotography.com/gorman.html when you click on the B&W conversion tutorial PDF button.

Oooh, a new-to-me method. I'll have to give it a try. So far I've mostly stayed with B&W. But I'm starting to see the advantages of duotones etc. for more tonal range.

damonff · December 12, 2004

Tim Kirkwood wrote:

Wondering what the best way is to convert to B&W in PS 7?

Thanks guys

Tim

Hey Tim...I used this method for the latest challenge:

...if you're interested in the method...shoot me a PM...

~Damon

fish · December 12, 2004

Yet another (and possibly easier) method
Download some very cool b&w filters here. Free and give you the flexibility of simulating various b&w filters.

Example time:

Fotomatic red filter:

wxwax · December 12, 2004

pathfinder wrote:

I prefer the method promoted by Greg Gorham - you can find it at this URL http://www.gormanphotography.com/gorman.html when you click on the B&W conversion tutorial PDF button.

So I converted this:

... to this, using his method and using a mauve duotone. I'm surprised at how easily it made a nice image.

Tim Kirkwood · December 12, 2004

Thanks for all the great tips guys. I will have to take some (well ok alot:D ) of time reading and tryin this out.

Thanks
Tim

ginger_55 · December 14, 2004

I use two or three methods, combine them, keep what works, sometimes three at once. You all would be horrified.

I don't want to know any more methods or I would have to put them in the mix, too.

ginger

yvonne · December 22, 2004

Is there a specific reason why people go vs mode/greyscale/channels

when to my eye pressing desaturate gets the same result? (If I want to play with the blacks I then use curves afterwards).

cletus · December 22, 2004

yvonne wrote:

Is there a specific reason why people go vs mode/greyscale/channels

when to my eye pressing desaturate gets the same result? (If I want to play with the blacks I then use curves afterwards).

The Mode>Greyscale method does a simple average of the color channels to produce a greyscale image. Some of the other methods give you more flexibility in choosing how the color info gets used in making the greyscale image. Here is an example:

Original:

Mode>Greyscale:

Channel Mixer:

If I remember correctly, the Channel Mixer version was created using just the red and green channels. As a result, the blue sky is much darker, while the brick on the church (which is almost all red) is brighter.

yvonne · December 22, 2004

but what about "desaturate"? Does that do the same thing as greyscale on off, then?

cletus · December 22, 2004

yvonne wrote:

but what about "desaturate"? Does that do the same thing as greyscale on off, then?

Edit: After reading rutt's post below I realized that my orignal answer was wrong. The correct answer is No.

yvonne · December 22, 2004

ah ok, fair enough then. so it really makes no difference... the improvement is in the curves and or channels, depending on which is your preference.

rutt · December 22, 2004

I hate to repeat myself on this topic, but I'm going to anyway. Understanding is power. Get Dan Margulis' Professional Photoshop and read the chapter Friend and Foe in Black and White. If you understand Dan's points, you will be able to do much better B&W conversions than if you just follow a recipe or go on gut feel.

PS has a nonobvious algorithm that it uses for B&W conversion. When it converts RGB to greyscale, it uses a weighted average.

Each new B/W pixel gets about 60 percent of the value of the green component or the RGB, 30 percent of the red, and 10 percent of the blue. Professional Photoshop, page 195

That means that a naive conversion (image->mode->greyscale, or taking the L channel from LAB) will pretty much discard the info from the blue channel. Is this what you want? It depends on the image and where the contrast is.

Consider the following:

Here's what happens when with mode->greyscale:

Not so good, eh? Of course, this example was carefully constructed using my knowledge of PS's conversion algorithm, but it illustrates something that is there every time one does a B&W conversion. These conversions lose information, by definition. So you have to decide what's important and what isn't. Where is the information you want to keep and where is the information you don't care about or want to lose.

Recently, I've been doing this:

Copy image (and work on the copy)
image->mode->greyscale
apply image (apply the green channel of the original to the only layer of the copy)
duplicate layer
apply image (apply the red channel of the original to the new layer of the copy)
duplicate layer
apply image (apply the blue channel of the original to the new layer of the copy)

Now you have the information from each channel in a sepaate layer of a greyscale image. You can then play with opacity other blending options to get what you like. Often you just want not to lose any information, and then I find that using "darken" or "multiply" as blending modes works well. Try stacking with green on the bottom and red on the top. Use darken for the blue (middle) layer and multiply for the red (top) layer. This often works well for portraits. Try to get to the point where you have an image that has all the information you want and loses what you dont' want to keep. Don't worry at this point about exactly how it looks, becasue you can still use curves and shadow/highlight and the like afterwards to fine tune.

Good B&W conversions require as much attention as good color correction. I think a lot of times, people convert to B&W because they are frustrated with trying to get good color from a particular image. Often the result is bad B&W. This might not be as jarring as bad color, but it isn't as good as it can be.

In the spring when Celtus had his B&W conversion assignment, I also did a converstion of his church as an excercise in my understanding of the chapter from Dan's book. What do you think:

pathfinder · December 23, 2004

rutt wrote:

I hate to repeat myself on this topic, but I'm going to anyway. Understanding is power. Get Dan Margulis' Professional Photoshop and read the chapter Friend and Foe in Black and White. If you understand Dan's points, you will be able to do much better B&W conversions than if you just follow a recipe or go on gut feel.

PS has a nonobvious algorithm that it uses for B&W conversion. When it converts RGB to greyscale, it uses a weighted average.

That means that a naive conversion (image->mode->greyscale, or taking the L channel from LAB) will pretty much discard the info from the blue channel. Is this what you want? It depends on the image and where the contrast is.

Consider the following:

Here's what happens when with mode->greyscale:

Not so good, eh? Of course, this example was carefully constructed using my knowledge of PS's conversion algorithm, but it illustrates something that is there every time one does a B&W conversion. These conversions lose information, by definition. So you have to decide what's important and what isn't. Where is the information you want to keep and where is the information you don't care about or want to lose.

Recently, I've been doing this:
Copy image (and work on the copy)

image->mode->greyscale

apply image (apply the green channel of the original to the only layer of the copy)

duplicate layer

apply image (apply the red channel of the original to the new layer of the copy)

duplicate layer

apply image (apply the blue channel of the original to the new layer of the copy)

Now you have the information from each channel in a sepaate layer of a greyscale image. You can then play with opacity other blending options to get what you like. Often you just want not to lose any information, and then I find that using "darken" or "multiply" as blending modes works well. Try stacking with green on the bottom and red on the top. Use darken for the blue (middle) layer and multiply for the red (top) layer. This often works well for portraits. Try to get to the point where you have an image that has all the information you want and loses what you dont' want to keep. Don't worry at this point about exactly how it looks, becasue you can still use curves and shadow/highlight and the like afterwards to fine tune.

Good B&W conversions require as much attention as good color correction. I think a lot of times, people convert to B&W because they are frustrated with trying to get good color from a particular image. Often the result is bad B&W. This might not be as jarring as bad color, but it isn't as good as it can be.

In the spring when Celtus had his B&W conversion assignment, I also did a converstion of his church as an excercise in my understanding of the chapter from Dan's book. What do you think:

I think your B&W conversion of the church is first rate - nice range of tones and contrasts.

fish · December 23, 2004

Here's what I get when I process rutt's colors with a fotomatic bw-plus yellow filter plugin (free):

ginger_55 · December 23, 2004

This is what I get with my basic conversion method, no adjustments

I know this is horrifying, but I find it fun.

first I convert to black and white on the hue/saturation adjustment,

then I up the black a tad in selective colors (can be done last)

then I go to channel mixer (hey the good photogs here seem to use that, so I threw it in). I lower the red to the middle area, 50 or 0, forget what it is called, I up the green to 100 and I leave the blue alone.

_________________________

After that the fun begins..............even Margulis says adjustments can or should be made after the initial work in LAB........I think he said that, well, I know he did. It impressed me.

But this is what I get..............before the fun starts. I can back up at any place along the way.

ginger

Well, that took 15 minutes...........now what?
doG, the holidays come and everyone disappears, even my children.
We are going up to them Christmas day, for a few days.

Any more games anyone wants to play? (The only thing is, it has to be something I am acquainted with.) Curves are pretty much out.

ginger_55 · December 23, 2004

Still have a few moments
I am, for fun, working on putting Shem Creek in black and white. This was fun.

Found it in an old shoe box of old East of the Cooper stuff:

Kept looking and there was one from the fifties or so, too.

So I went out and took this one:

The saturation was purposely kept low in the most recent one, wanted to keep the mood across the years.

g

ginger_55 · December 23, 2004

That first set kind of inspired me, so I took some of my
recent Shem Creek shots from the other night, worked them up in color: I mean that is sweet light, basic color photography right. Decided to check them out in black and white or sepia.

rutt · December 24, 2004

fish wrote:

Here's what I get when I process rutt's colors with a fotomatic bw-plus yellow filter plugin (free):

The point of the stripes is that every B&W conversion involves making decisions. There can be no single correct way to make these conversions.
If I knew a little more about the fotomatic filter, I'm sure I could doctor the stripes so that it would render them all the same color (unless it is much smarter than I think it is.)

Here are some different conversions of the stripes.

PS desaturate

Green channel

Blue channel

Red channel

R 126 / G 94 / B 4

R 92 / G 34 / B 64

My point is that B&W convesion always involves artistic choices just as profound as the ones you make when you are shooting. You can't wish this away. If you cede control over the process to some piece of software or some fixed recipe you have also made a choice -- the choice not to think about what you are doing. The result is nearly always worse than if you pay attention and make the choices yourself in order to make the image you want.

Getting good realistic looking color is often difficult, but it is no less difficult to get B&W that says what you want. Next time you do a B&W conversion, be very critical of the result. Look at an Avedon or a Penn and compare your image to theirs. How does it compare in terms of tonal range and contrast. Is the fine detail missing? Does the image actually say what you want? And most importantly, why did you choose to convert to B&W in the first place? That's a profound decision. Make it without good reason and you end up with junk.

ginger_55 · December 24, 2004

I did a lot of conversions last night, later, after you all were long gone. Just more on that project of that one night. Think I finished.

I tried to remember something, so I could repeat it to all listening.

One time, I did not use the channel mixer, but don't remember why.

I did straighten some photos that really needed it (this was missed in the first color

workup)

I also reworked some color shots, a large part of this project seems to be showing the color with the black and white now.

In addition to always if only to use a +2, bumping the blk in sel colors, I also frequently used bumped, or lowered, the white, and sometimes I changed the neutral a bit, too.

When I was in the hue/saturation part of conversion, I sometimes, with caution, lightened the blk and white photo a bit.

In the shot taken in the parking lot, I did use the shadows/highlight tool. Made two versions. Will make a decison.

Examples of those "little things" that others do would be appreciated.

I did not sharpen anything. Am not sure I ever will again. But that is an inside joke, and, in truth, they had been sharpened in the original color workup.

ginger

Will start a thread on Shem Creek in black and white (and color) today. First I think I was just experimenting. Then, now, I guess not only do I want to put up a thread on that night, that place, I want to show that for some of us Blk and white is a choice of esthetics, not having anything to do with the quality of the color.

Though I can't say that my quality with anything is all that great, if it falls down, it should fall down in either blk and white or color. Also I did not take the "bad" shots and try to save them. There was more I could have done on the color side. Didn't.

Rutt, don't mean to disparage your information, I think any information is important, and I would never dismiss Margulis.

I thank you for bringing it to my attention..........then reminding me in these threads, smile. (Don't have to go out and buy the book anyway, it is here)

Conversion to B&W....

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