Hi @tue - thanks a lot for the suggestion! I've been thinking about ways to improve the integration between Color.io and Photoshop. I'm not sure how a plugin would improve the workflow much but I'd love to discuss ways we can optimize!

Here are some thoughts on this:

• We need a way to get full size images in and out of Color.io whether it's a plugin or a standalone app. Most filters that open in a separate window in Photoshop work like that. They take a layer of full size pixel data as input, perform some transformations and render the full size image back out to the main application.
• It's possible to copy and paste full size images in and out of Color.io with the built-in clipboard renderer (Right-click on viewport -> Copy / Paste). For some reason Photoshop doesn't allow copying full resolution layers to the clipboard which is a massive road block for what could be an excellent workflow. This seems like a pretty arbitrary restriction and we should ask Adobe to allow this: https://www.adobe.com/products/wishform.html
• I'm not sure if Capture One can render to the clipboard.
• You don't have to use Color.io in the browser. It can be installed as a fullscreen desktop app on Windows, macOS and Linux (https://www.color.io/user-guide/download-and-installation)

I personally think that copy / paste between PS / C1 / Color.io would be the most efficient and universal workflow. Color.io already supports this in both directions. The fastest way to get full-res images out of PS is to quick export a layer to PNG, then drag & drop that into Color.io. If Adobe can't enable full resolution clipboard rendering, it may be possible to cook up a script that renders lossless PNGs to the clipboard. I'll dig into the possibilities but I'm curious to learn if this would actually improve peoples workflow much.

Camera RAW Workflow: https://www.color.io/user-guide/create-luts-for-adobe-lightroom
Photoshop Workflow: https://www.color.io/user-guide/adobe-photoshop-workflow

I can't speak to the OP, but I find the workflow of moving in and out of Photoshop quite annoying. I have to remember to assign Display P3 Color Profile, then I have to export the image making sure to retain color space. (this can be really slow because, for whatever reason, the Photoshop "Export As" dialogue chugs like crazy, even on high-spec machines. I then have to save the file to a location, go to my browser, open color IO, import that image, set the color space to display P3, work on the creating the lut, export the lut, then load it into photoshop. (I also have to constantly clean up LUT files and exported images after I'm done)

Now of the above is difficult, its just tedious and annoying for every photo and often I find myself thinking: "meh, maybe il just grade it with adjustment layers rather than go through the annoyance of moving to color.io even if it is a way better tool"

It just would be so much easier if I could open a plugin that handles all of the above for me and then saves the lut back to an adjustment layer.