how to use color adjustments on grayscale clips

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Level 2

174 points

how to use color adjustments on grayscale clips

I do a lot more still photography than video. When I shoot stills, I often convert to grayscale but use color sliders to affect the tonality (the equivalent of using color filters on a lens when shooting black and white film). I know how to do this with Photoshop and Lightroom, but I can't quite figure out how to do it with FCP and Apple Color.

I know how to desaturate, but how can I adjust colors while maintaining a grayscale image?

Mac Pro 2.66GHz, Mac OS X (10.6.3), 5GB ram

Posted on Sep 22, 2010 3:39 PM

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Answer 1

Sep 22, 2010 4:12 PM in response to Jimtron

One way would be to add a Channel Mixer filter. Now add a HSV filter and slam the saturation to 0. Return to the Channel Mixer and tweak our colors' inputs there.

(The stacking order is important here, that's why apply the filters in the prescribed order.)

Actually, I forgot about the monochrome toggle in the Channel Mixer. This may allow you to get the effect you're after with only using one filter—not two.

Hope this helps...

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Answer 2

Sep 22, 2010 4:19 PM in response to Kevin Brock

Using the Channel Mixer, you can toggle on Monochrome
and "Allow Mono > 1" to avoid using the HSV filter.

Normal monochrome is .3R + .59G + .11B.

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Answer 3

Jimtron Author

Level 2

174 points

Sep 22, 2010 4:28 PM in response to stuckfootage

Thanks for the responses folks. I had tried the channel mixer before, but I can't get it to work. When I check "monochrome" in the channel mixer, the green and blue outputs get grayed out.

When I add HSV, and set that to -1 (0 doesn't make it grayscale), then when I adjust the channel mixer sliders it adds color back (an overall tint).

What am I doing wrong?

Message was edited by: Jimtron

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Answer 4

Sep 22, 2010 4:32 PM in response to Jimtron

Jimtron wrote:
When I check "monochrome" in the channel mixer,
the green and blue outputs get grayed out.

Yeah, you don't need three outputs. It's black & white.
So the Red Output becomes the white output.

You do have R, G, and B INPUTS, though, which is where you do the mix.

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Answer 5

Jimtron Author

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174 points

Sep 22, 2010 4:40 PM in response to stuckfootage

OK, I'll give that a try, thanks.

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Answer 6

Zebulun

Level 5

6,749 points

Sep 22, 2010 4:48 PM in response to Jimtron

Do not apply Monochrome in the Channel Mixer. Apply a separate Desaturation filter after the Channel Mixer.

Personally I'd probably use the RGB Balance or the fxplug Color Balance for this instead of the Channel Mixer.

Whatever you use, apply a separate Desaturation filter last.

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Answer 7

Zebulun

Level 5

6,749 points

Sep 22, 2010 4:50 PM in response to stuckfootage

It will actually look better if you have control over the RGB outputs even though it is grayscale, hence, applying de-saturation as a separate filter at the end of the stack is more effective.

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Answer 8

Sep 22, 2010 5:19 PM in response to Jimtron

Jimtron wrote:
What am I doing wrong?

Stacking order?

"Right"

"Wrong"

The filters above have the exact same settings. Only difference is the order they're stacked in.

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Answer 9

Jimtron Author

Level 2

174 points

Sep 22, 2010 5:36 PM in response to Jimtron

Thanks again, this is all helpful. I did get the channel mixer to work with HSV by changing the stacking order. However, RGB with Desaturate so far seems to work better, though I haven't yet spent a lot of time with this.

Any other suggestions are welcome.

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