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IRW

Splitting and Merging RGB channels

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I am a scientist and I have been using Photoshop for 8 years now to edit my images and make montages. I recently decided to use Affinity Photo and designer to make my images and I am really struggling with Affinity Photo as far as splitting and merging channels go. This was super easy in PS. You go to channels, split channel, delete channel or resign new colors to channel, merge channel and you are done. Then you copy this on a canvass. And if you want to show gray scale images of the RGB image, you just go to that channel, copy paste it (An example is shown below). I can't seem to find this option in Affinity Photo. There is this create spare channel option which lets you assign new profiles (change green to red or blue or delete a channel) but then you can't copy/paste this onto a canvas in designer! Is there a way to do this?

Here is what I want: Most of my images are in RGB. I may want to delete a channel or switch colors for channels. Merge them so I have a new RGB image. and then I want to show individual channels by themselves in grey scale (example of this is attached).

Fig.2.8_MMP1.psd

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Thank you for the response. I appreciate it.

Select a Pixel object then right-click on the thumbnail of the required channel (not a Composite channel) and pick Create Greyscale Layer.

I have to flatten the document to get the pixel objects (the default seems to be background object). But this pixel object for each channel disappears as soon as I reduce noise or play with levels or delete a pixel object to get rid of a channel. Also, on the pixel object,  I can create the gray scale there but then then I can't process the image the further. The composite does not refresh and when I go on other channels, all I see is gray scale of the channel I just created irrespective of what pixel object or spare channel or composite you click. I have to undo the grey scale. Is that the only way? Also, I did figure out that you can create a spare channel to swap colors but once you do that the pixel object layers again disappear. Is there a specific sequence in which you have to process your image?

 

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5 minutes ago, IRW said:

I have to flatten the document to get the pixel objects (the default seems to be background object).

Flattening should not be needed.

With a pixel object selected, you want the Pixel channels (Pixel Red, Green, Blue, Alpha). Those are for the selected object. The Composite is for the entire image.


-- Walt

Windows 10 Home, version 1903 (18362.356), 16GB memory, Intel Core i7-6700K @ 4.00Gz, GeForce GTX 970
Affinity Photo 1.7.3.481 and 1.8.0.486 Beta   / Affinity Designer 1.7.3.481 and 1.8.0.486 Beta  / Affinity Publisher 1.7.3.481 and 1.7.3.475 Beta

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On 4/13/2019 at 5:53 PM, >|< said:

applying the Rasterise comman

Select the layer/object and click on Layer > Rasterise.

John


Windows 10, Affinity Photo 1.7 and Designer 1.7, (mainly Photo), now ex-Adobe CC

CPU: AMD A6-3670. RAM: 16 GB DDR3 @ 666MHz, Graphics: 2047MB NVIDIA GeForce GT 630

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You are right. I guess after I edit the image the way I want, I guess I need a pixel layer to copy paste into affinity designer. Otherwise it just says 'adjustment layer' in affinity designer.

Thank you for your help.

With the same image, once you create gray scale, does the image 'freeze' for you? i.e. you can't make any more changes unless you undo that command. I ask because in an RGB image, sometimes I need gray scale for Green and red. But if I convert the green to grey scale, I have to go back all the way till I undo that command and then convert the red into gray scale.

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