Photoshop Channel concepts: The Power of Ten

[cricket1961]

I have enjoyed your input with this discussion and the power of 10 Michael. Verynice input about a subject that is not talked about enough .

I have also been a huge calculations and apply image user since version 2. I find it indispensable to a lot of the work I do, not just my beauty work. I find that your use of "10" channels is very good theoretically, but I believe that you do not need to go to each of the other color spaces or different profiles to achieve what you have. I like what was done to the tiger with the technique you used above Michael, but the loss of some saturation and detail in the orange of the tiger and the "greying"out of the stripes is, at least to me, in the opposite direction and I believe hurts the way the tiger does pop from the background.
Strokers techniques are awesome and are very similar to the ones that I use. THe power of what he does is that he doesn't need to go to other color spaces to get the results he does. And while I love the ability to pick which tool I use to achieve my channel blending, I really would love some of the tools he has created, but alas, I am a mac user and the tools are for windows users only.

[Graphics23]

Hey Chris, thanks for joining in!

How about sharing some of your Calculations and Apply Image techniques?

Regards,

Michael

[Stroker]

But the "B" of HSB, the "L" of HSL, and the "L" of LAB, are pretty much identical.

B in HSB and L in HSL are kind of similiar. The formulas are rather simple and can be done with stock tools. They are kind of like step brothers or something.

L in Lab and Lum in HsY are nearly identical. If I remember correctly, you have to look into XYZ colour space (conversions) to see how nearly identical they are. Like, out to three decimal places or something.

Cheap and easy way to get Lum in HsY:
-Edit > Fill
-- Using: Black, White, or 50% Grey
-- Mode: Saturation

Another option, which is a dynamic in the Layers palette, is to fill a new layer with any shade of grey and set blending mode to Saturation.

Tada. You know have the next best thing to L in Lab without having to convert to Lab.

One of the main advantages of using Lum in HsY (or L in Lab) is that the channels are weighted. This means that yellows will be brighter and blues will be darker. If you have a photograph with lots of highly saturated hues, desaturating to L in HSL will wash-out the photograph a tad. Whereas Lum in HsY (or L in Lab) should give you more contrast to work with right off the bat.

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Apply Image and Calculations

I adore Apply Image, but I don't really use Calculations at all.

One day Mr. Cox said that Layers were meant to replace Apply Image. After thinking about that for a bit, I realized that the things that Apply Image can do can also be done in the Layers palette - but the Layers palette has the benefit of Adjustment Layers, Clipping Groups, and what-not. Think of it as tweakable Apply Image on crack. Layer ChOps as I call the techniques.

But moving things from the Channels palette to the Layers palette isn't always worth the effort. For the simple things, prolly best to stay in Channels.

For a little more finese, tweakability, and visual feed-back, take it to Layers. Can go a long way to taking out the hit-or-miss inherent in Apply Image (but I'm not sure about hit-or-miss in Calculations). Wanna adjust the choke on blues in the midtones? Layer ChOps.

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Too much on my mind regarding these things. Going to digress and hide under my rock for a bit.

[Graphics23]

Originally Posted by Stroker

Another option, which is a dynamic in the Layers palette, is to fill a new layer with any shade of grey and set blending mode to Saturation.

Tada. You know have the next best thing to L in Lab without having to convert to Lab.

That's a great move, I use it quite often myself.

I adore Apply Image, but I don't really use Calculations at all.

I've been experimenting with Channel Blending a lot lately, so I use Apply Image more than Calculations. But Calculations comes in pretty handy when creating masks.

I recently starting using Calculations to combine two channels which were then used with Apply Image for the final blend, so as I experiment with Channel Blends I find I'm using Calculations a little more than just for masks.

One day Mr. Cox said that Layers were meant to replace Apply Image. After thinking about that for a bit, I realized that the things that Apply Image can do can also be done in the Layers palette - but the Layers palette has the benefit of Adjustment Layers, Clipping Groups, and what-not. Think of it as tweakable Apply Image on crack. Layer ChOps as I call the techniques.

But moving things from the Channels palette to the Layers palette isn't always worth the effort. For the simple things, prolly best to stay in Channels.

For a little more finese, tweakability, and visual feed-back, take it to Layers. Can go a long way to taking out the hit-or-miss inherent in Apply Image (but I'm not sure about hit-or-miss in Calculations). Wanna adjust the choke on blues in the midtones? Layer ChOps.

There's one thing that Apply Image allows for that can't be easily reproduced with Layers alone, that's combining Blend Modes.

For example, using Apply Image set to Darken mode on a layer that's set to Luminosity.

And what would we do to manually create Layer Styles without Calculations? Some of Bert Monroy's photorealism techniques absolutely require it and can't be done otherwise.

What's so "hit or miss" about Apply Image? You have a preview and immediate feedback. Other than needing to be very familiar with the various blend modes it seems pretty straight forward to me.

So I would be very displeased to see Apply Image and Calculations go away. If anything they should get a redesign based on what Bert suggested in his Channel Chops book.

Too much on my mind regarding these things. Going to digress and hide under my rock for a bit.

Well, I sincerely hope you come back for further discussion. I really appreciate your contributions and would very much like to hear more of how you use Apply Image and Channels/Color Modes.

Regards,

Michael

[Stroker]

There's one thing that Apply Image allows for that can't be easily reproduced with Layers alone, that's combining Blend Modes.

For example, using Apply Image set to Darken mode on a layer that's set to Luminosity.

That can be done in Layers palette. One layer set to Lum, then clip a layer to it set to Darken.

When I use Apply Image, I don't really pay attention to the preview/document. If there is visual feed-back, I've never noticed it because I always know exactly what I'm after and exactly what I'll get. Since there is no hit-or-miss in my head, I haven't bothered looking for hit-or-miss in the preview/document. My bad assuming that there wasn't an immediate preview.

I can't say I'm familiar with Monroy's techniques in this area. But I do know how to replicate the Layer Styles completely in the Layers palette without Apply or Calc. Well, I haven't checked them all explicitly, but I do know I can do most of them for sure.

Trying to do Monroy's techniques in Layers without Apply/Calc might be an interesting diversion. If you post one up and point me to it, I'll crawl out from under my rock again.

Rock. Again. I mean it this time.
Unless a Monroy Apply/Calc technique is posted and I'm pointed to it.

[cdsmile]

Thank for this tutorials ..i sorry i am abit in english language