rui_mac

Do you know how the data structure is stored? Is it a list [witdth, height, 2] matrix or two [width, height] matrixes? And, no matter how they are stored, they are two matrixes with the same structure, containing the same data type values. So, once again, there is no excuse for not being able to perform the same operations on a "opacity map" matrix that can be performed on a "greyscale" matrix. I'm a coder and I know what I'm talking about. One of the last plugins I coded as a 3D vertex painting set of tools. It deals with RGB and, optionally, with an opacity map. The same set of code that is used for each of the R, G and B channels (that are, fundamentally, three greyscale channels), is the one I also use for the opacity map. I even coded Dodge, Burn and Blur tools and they work the same at the RGB level as they work at the opacity level.

If you pay so much attention to definition details, what would you say that the individual channels of an RGB image are? Chromatic? Or achromatic? Because each individual channel has no color information. It just contains a list of values that define the intensity of each individual component. Just like a greyscale image is just a list of values that define the intensity of light of each pixel. Just like an alpha is just a list of values that define the opacity of each pixel. If they are all the same (and stored the same way, internally), why can't you perform on an alpha channel the same operations that we can perform on a greyscale?

The greyscale values are just a single list of values. A "greyscale LAYER" includes the greyscale list of values and a n opacity list of values. All layers include an additional list of values for the opacity. So, a greyscale LAYER is simple a set of two "greyscale" lists. And an RGB LAYER is a set of four greyscale lists, one for Red, one for Green, one for Blue and one for opacity. Once again, there is no excuse for the opacity list (call it alpha, or key, or mask, or opacity map, or whatever) that is merely a list of values just like a greyscale image or any of the composite channels of an RGB or CMYK image, to be treated differently. In a nutshell, an alpha channel is exactly the same as a greyscale image and should be treated the same way, allowing all tools and operation that a greyscale image allows.

Internally, aren't they the same? Just a list of values! If they are (and they are), there is no reason for us to not be able to manipulate an alpha channel as a greyscale image.

If the nomenclature is so important, then... Greyscale images, alpha channels, color component channels, transparency maps, etc, ARE ALL A MATRIX OF VALUES, as in... a long list of 8 bit or 16 bit numbers. So, all operations that can be done with one, should be possible with all others. Are you telling me that a transparency map is not a list of values?

Maybe that is one of the reasons Photoshop is so much better than any other application to work with Alphas.

Please, someone tell me what are the advantages of having "achromatic (colorless)" alphas instead of grayscale alphas.

Let me add a few things. It seems that AP is pre-multiplying the alpha with the RGB, and that is the culprit of the black halo around keyed images. It is usually impossible to produce a Straight alpha from real life photography. But a digital application should never pre-multiply alphas, when not requested. So, at the very least, we should have the option of pre-multiplying the alpha... or NOT!!! Also, let me provide another example of a simple workflow that I use a lot in Photoshop and it is simply impossible in AP. When cutting out a subject from its background, sometimes I need to choke or spread the alpha in some specific places, to prevent halos. So, in Photoshop, I simply activate the alpha associated with the layer, locally blur the alpha on the the places that I want to adjust and then use the Dodge and Burn tools to choke or spread the alpha. In AP, I can locally blur the alpha. But neither the Dodge nor the Burn tools work with the alpha. Why can I blur but not dodge or burn? Also, I can easily run filters on alphas, in Photoshop. Wether they are additional alpha channels or even if they are layer alpha channels. They are all the same, in Photoshop. In AP, some filter work, some don't. Add Noise doesn't work, for example. And some that work, produce unexpected results (Dust & Scratches, for example). If I try to work with an alpha as a regular layer and Option+click to see the whole alpha, Select All, Copy, and Paste, I create a new alpha. Come on!!! I want to create a new layer with the alpha information. it is like the alpha is an half baked greyscale image where only a few tools are allowed.

Besides doing image editing for video (where alphas are required), I also do lots of image editing for 3D texturing (where alphas are also required) and I also do photo retouching and calibration for printing where... guess what, ALPHAS ARE ALSO REQUIRED. Dealing with alphas is a must for any professional that works with images, no matter what field it works on. Is it professional work? Ok, so, dealing with alphas is required. And working with alphas should be as straightforwards as working with any greyscale image. Whatever could be done with a greyscale image should be possible to do with alphas, and it should work exactly the same way. Alphas ARE greyscale images!!! Alphas are just information about opacity. So, why are alphas different in AP? I have been asking this ever since the beta versions of Affinity Photo and, if I recall correctly, I was told that working with alphas would be addressed and that it would become easier. It hasn't! It is still a nightmare. Will it ever change? As it is now, I can't work with alphas in AP.

Honestly, I have been trying to give Affinity Photo a chance, dealing with channels and trying to do in Affinity Photo whatever I do in Photoshop, with the composite channels and with additional alpha channels. And, either it is very cumbersome and not very intuitive, or I can’t do it at all. This is really forcing me to avaluate the type of work I need to do, to decide if I should use Photoshop of Affinity Photo. I really hope the way channels operate, and the amount of stuff we can do with them, improves in the future. Hopefully, in a nearby future.

Please. Please. PLEASE!!! Add a way to view documents with a different aspect ratio than 1:1 I'm doing 16:9 anamorfic (720x576).

I shared this video before, showing the way I use channels to create masks. This procedure is very easy and straightforward in Photoshop, but complicated or impossible in Affinity Photo 😞 https://www.youtube.com/watch?v=W6H_8gjX-eI

Here are the captures I did from FreeHand, and its amazing Search tool:

A long time ago `presented here the Search functions of the old and defunct FreeHand. They were amazing. I wish we had such a thing. Let me search for the post I made.

The way Affinity Photo deals with alpha channels/masks is the only thing preventing me to ditch Photoshop 😞