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papalar

using channels as non-destructive way to color wallcovering patterns

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Hello,

 

I am trying out Affinity Photo as a replacement for CS6 Photoshop. Coloring b&w artwork with channels is something I do in Photoshop. I create an alpha channel then paste in my b&w (or greyscale) artwork . I create as many channels as there are in my print design - usually two to three plus a base color. I can set the opacity of the channel to closely mimic the transparency of gravure printing (what my plant uses). I can also change the color of the channel as many times as I want without ever changing the b&w artwork pasted into the channel.

 

I do not see a way to do this in Affinity. When I try opening an existing PSD file these alpha channels do not appear. There may be a way with layers but only if I can preserve the artwork's tonal structure. I need each layer to multiply and create a composite color of the combined artwork layers. I have attached a simple PSD file to illustrate.

 

Otherwise Affinity is a really good fit for the mural work I do. I like the interface, features and effects. The scale-up test I did produced better results than Photoshop.

 

Thanks,

 

Larry

8.5x11 2color RGB.psd

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Does the layer blending mode Multiply give you similar results if you do this in layers instead of channels?

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papalar, I don't know enough to offer a solution to you but I am very interested in your method for coloring greyscale art for a different kind of project. I looked at your posted file but I can't figure out how you applied the color to the channels you made. Could you possibly explain further? Perhaps someone would then have a solution you can use in Affinity.

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Asha - I tried setting the layer blend mode to multiply and that does give a transparent color over color effect - but the artwork placed in the layer has to be converted to a color. And depending on the darkness or lightness of the color I will lose the tonal structure of the grayscale artwork. In Photoshop the color overlay option allows me to "overlay" any color I want over my grayscale art. The problem with that method is that I cannot multiply several grayscale layers together without the whole going dark. Coloring in channels allows for the grayscale art to be colored it in a non-destructive manner and provides a very close mimicking of gravure printing - which is transparent color over transparent color and we use separate printing cylinders for each color/pattern. I will continue looking for a solution. I was able to do it in Gimp after some trial and error.

 

jmac - click open the channels tab (in Photoshop) and double click on the print1 channel (in the open area), a color dialog opens, click on the color block and adjust the color. I uploaded two more files that illustrate two different methods for coloring grayscale artwork that I made for a storyboard artist. You will see that both files have the same painted color layer but different results.

channel method.psd

color method.psd

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I opened the file channel method.psd. It has 4 channels--R, G, B and Spot. I see that the Spot channel is your linework detail, and RGB contains the color info. I'm not an AP expert, but in browsing around the help and looking at your file, it appears to me that channel editing is mostly controlled from the layers. You can turn off or lock any of the RGB channels in the Channels panel, and then paint in white/black/gray paint on the layer to change the color on an individual channel. I got stuck in trying to figure out how to get the linework to work in a channel. I think it would need to be transparent in the paper white areas, and then you can make a pixel selection and create a spare channel. Even then I am not sure it would work the same way. I was able to get a similar effect as your PS file by importing the linework into a layer, rasterizing it, and then turning the blending mode to Multiply.

 

ETA, I also looked at color method.psd. This is closer to what I was able to do in AP for the channel method, except that the color layer was Normal blending mode and the linework was on the top layer in Multiply blending mode.

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Here is a way to color grayscale art in a non-destructive way.

First import a grayscale art image into a new layer, invert it, then right click on it and rasterize to mask (in the layers menu). Add a new layer underneath the art layer and fill it with a color. Group these two layers together and set the group to multiply. Do the same for each grayscale art layer you need setting each to multiply. Create a base color layer in the same way except fill it with a solid white then rasterize it to mask and add a color layer underneath as well. Leave the base group set to normal.

Once a file is set up in this way click on each color layer below the art layers and fill with different colors using the paint can tool. The multiply group setting allows each grouped print layer to multiply down to the base and create composite colors like a gravure print / transparent over transparent color. You can also command U to open a color adjustment layer above the color layer and adjust the sliders then merge.

 

multi-color print.afphoto file attached to illustrate method...

 

multi-color print.afphoto

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Nice exploration!

 

By inverting & rasterizing to mask are you not creating a screen? Why not just set the original artwork to screen? The rest of the setup stays as you've said. 

Saves a couple of steps on each design layer, and the original artwork is truly untouched (I know you can get it back from mask if you really want to, but that again is a couple of steps).  :)

 

(p.s. You could even do the opposite. Put the color, set to screen, on top of the artwork... Seems a little less intuitive that way though.)

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Tried to screen the grayscale layer over a color layer - it does not work like a I need. Looks like the invert then raster to mask is the best solution so far. Ideally the grayscale should be loaded to a separate channel (spot channel in Photoshop) with the ability to add color.

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Okay - I see now. If the grayscale layer is set to screen and the color layer below is set to normal / group the two together / then do multiply for the group and it works the same as my previous method.

 

Thank you. That is a more straight forward way to do it. I like that better.

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