Create amazing color effects using Affinity Photo channels with filters. Open a document and then go to the panel via View menu and studio and channels. Once you have the panel displayed, you will notice a number of panel entries such composite red + composite green + composite blue + composite alpha and a number of others depending on the document. This also depends on the color / image model for the document so the list will be different if you are using CMYK or LAB
You can right click context menu on any of the panels, to display commands such as load to pixel selection; subtract from pixel selection; create spare etc
To select an entry on the panel such as composite red and then you will see the pixels in the red only in the document (you will notice all the others are disabled / hidden etc). Select the composite green etc (or cyan etc). Select the blue etc to change the blue pixels.
To reset back to all (red, green etc), click the little circular reset at the top of the panel to bring them all back on-line. Click the circular reset button at the top of the panel. As soon as you click that, you will see all the artwork go back to the standard RGB. You can then repeat the process of selecting individual red green etc and applying the effects etc
You can use the effects (blur, sharpen, procedural texture etc) in the red as well as the green etc independently. I have yet to use an effect that doesn't allow for this but they may exist for other color modes. Go to the panel and select the composite red. So now, go to the filters menu and distort and equations (you could equally use blur or radial blur or some other) and then you will see the equations editor panel. Using the default coordinate system and set extend mode to wrap and the x= to x+500 etc (half of the current size of the document, I don't know if there is an equations constant for the document width) and then you will see the image shift in the red only half way and wrap half way. Click apply.
Now select the composite green in the panel. go to the filters menu and distort and equations and instead of using x+500 etc, set the y= value and set to y+500 etc (depending on the height of the document and half of that). Again, select wrap and then click apply.
Go to the composite blue and run the same effect and now click the polar option and wrap and set the r= to r+200. Now you have edited all of the entries independently, click the little circular icon at the top of the panel or go through all the channels and click the visible and editable icons and you should see an unusually colorful shifted design (but still recognizable as the image). You can also apply the same to the RGB or CMYK and then repeat the above process
You can also use panel and layers to create some interesting effects, combining those layers with blending modes. Select an image. Go to the layers panel. Layer menu and duplicate. Layers menu and duplicate. You should now have three layers all with the same image. Uncheck (hide) the first two top layers via the layer panel. Go to the visible layer. Go to the panel and select the composite red. Apply an effect such as radial blur. Go to the panel and select the composite green. Now check the middle layer in the layer panel and use that layer. Apply effect with different settings. Go to the panel and blue. Select and check (make visible) the top layer. Apply the effect. Go to panel and click the reset at the top of the panel to display RGB. Go to each of the layers in the layer panel and set the blending modes accordingly such as difference or overlay. You should then see the effects applied to the red and green and blue and also the result of the blending modes applied to the layers.
As with above and layers, you can use this approach with all kinds of effects such as deform and blurs etc, you can also mix and match as well so go with blur / deform for the red and then box blur and shear for the green and zoom blur and twirl for the blue etc. Once you have used all these you can always reset and then apply a deform effect to the entire RGB image.