Fotoloco

Here’s the same example, contrasting with the old method: (.afphoto file attached at the end.) sat mask old.afphoto

Here’s an example for the new method: (.afphoto file attached at the end.) (Note also that if you blend (mode = “overlay”) the hue/saturation layer over the luminosity layer, you get the original layer back... so this can also be used for other purposes.) sat mask new.afphoto

Thanks for sharing this! I’ve used this for a while now - the only issue is it underestimates saturation somewhat if the luminosity is not always 50 (HSL value). I found a way to make a layer where hue/saturation is preserved, but luminosity is set to 50. This resolves the issue. (Note: blending with a layer where luminosity is 50 with the “luminosity” blend mode does not work - nor do any similar approaches. The luminosity result is close to 50 but varies, and hue/saturation values are affected.) Here’s how to map saturation values exactly to luminosity values: 1. Create a HSL adjustment layer, and set saturation to -100. (Don’t turn on HSV!) 2. Merge visible. The result is a B&W layer that contains only luminosity values. (Note: desaturation, setting color to grey, etc. using pixel/fill layers/curves does not get this quite right!) 3. Invert the B&W luminosity layer, and set blend mode to “vivid light”. 4. Merge visible. The result is a layer containing only hue and saturation values. Luminosity is constant (always 50 by HSL). Now that you have separated luminosity and hue/saturation into their own layers, apply the instructions you shared above to the hue/saturation layer: 5. Create a HSL adjustment layer, and set saturation to -100. (Turn on HSV!) Set blend mode to “difference”. 6. Create another HSL adjustment layer, and set saturation to -100. (Turn on HSV!) Set blend mode to “normal”. 7. Merge visible. The result is a B&W layer containing only saturation values, mapped to luminosity values. This is your saturation mask.

Here’s some screenshots of how to set this up. It’s really simple even without the macro. freq sep.afphoto To make your high pass layer: 1. Duplicate your layer, and invert the duplicate. 2. Apply your blur filter to the duplicate (or anything else crazy you can think of). 3. Set the blend mode to average. (Optional: group these two layers together and set the blend mode for the group to linear light. This allows dynamic editing of the high pass layer.) To make your low pass layer:. 1. Apply your blur filter to the original layer (or whatever you did in step 2 for the high pass layer).

There’s a relatively simple way to do frequency separation I figured out a while ago. I shared a macro that automates this process (see the first link below). I rarely use the frequency separation filter anymore, since the macro is far more powerful: you can use any blur mode you wish to make the low pass layer (I strongly suggest trying median blur, or a denoise “blur”), and can do some rather creative stuff (try using a hue/color/luminosity modified version of the layer as the “low pass”). I think I also included a macro that generates a high pass layer alone, and some really cool sharpening/denoise/color correction can be done without being locked into Gaussian blur as the low pass source. For details on how this works, look at the second link below (steps 6-9 are the FS ones). Note that this will work on the iPad version - the method with apply image can’t be done on the iPad easily as it doesn’t allow selecting a layer within the document as a source.

This, and brush tools. Would be VERY nice to not have to open them a thousand times.

Also this site mentioned previously has the formulas for reflect and glow: http://www.pegtop.net/delphi/articles/blendmodes/quadratic.htm I confirmed this is how Affinity Photo's versions of these blend modes work. For example with reflect, if you multiply the blend layer by itself, then color dodge it by the base layer, you get the some result.

Divide is still not available on any platform AFAIK. Don't know why, but you can use color dodge instead if you invert your blend layer. Same with linear burn which would be nice to have... The workaround is to use subtract, and invert your blend layer.

Thought I would mention something I just figured out about the negation blend mode: it is equivalent to the difference blend mode if the blend layer and result layer are both inverted.

This would be really nice and simple to add.

It would be very handy if we could make groups that take input from lower layers (like with the pass through blend mode) while allowing selection of any blend mode for the group. For example, you could use a pixel layer inside the group to apply an overlay blend, and then set the blend mode for the group to luminosity if the shift in colors/saturation is undesired. I use tricks like this all the time but currently I have to flatten the layers below and insert them into the group, which prohibits dynamic editing of those layers.

Bump... I still think this would be a hugely helpful addition.

IMO, the ideal solution is to provide a HSL-type adjustment that allows only the selected color/hue range to pass through (effectively like a bandpass filter in music). It could be used to make a mask, and therefore used with any other adjustment or layer.

We really need this... Any creative workarounds in the meantime? I haven't come up with anything that comes close to replicating the results of this approach in Photoshop.

Yep, we need this.