adobe dng raw support

Apple's Preview can read .dng files from supported Camera RAW cameras, or if Adobe's DNG converter supports the camera for conversion to DNG format.

Yes. I tried a few and Preview had no problem opening them.

Most likely macOS cannot deal with the Topaz DNG files because just as macOS has data regarding allowable camera RAW support, it also has other data regarding DNG support by camera type, and Topaz is not included.

FWIW, I downloaded the trial of Topaz JPEG to RAW AI and converted a few jpegs. As you stated Preview will not open the resulting DNG files. Along with what you mentioned, Affinity Photo, GraphicConverter 11, Photoshop Elements 2020 and XnView MP all open them as well.

However, I have a program (Topaz JPEG to RAW) that converts jpegs to RAW images.

It doesn't. Camera Raw is produced only by the digital cameras such images come from. There's no way to get back to that state from a JPEG, TIFF, or any other non-RAW file format.

It also doesn't do anything the Camera Raw plugin for Photoshop can't. You can open any RGB, or even Grayscale file and work on it in Photoshop with the same controls RAW images offer.

Still, it's a nice tool if you don't have Photoshop since it gives you those kinds of editing controls.

Thanks, but I know. Trouble is, it's impossible to do that. JPEG averages image data into 8 x 8 blocks of pixels and throws out the original data completely. There is no way at all to recover the original data. It isn't stored anywhere in the file.

A level 12 JPEG is nearly identical to an uncompressed TIFF, but still takes up less space. But then, so does saving a TIFF with LZW compression, which is lossless.

Let's say you start with a TIFF and save a copy as level 12 JPEG. Open that and drop it over the TIFF in Photoshop. Then turn the top layer (the JPEG pixels) on and off. You have to look pretty closely to see a handful of pixels change color.

But as I'm sure you're aware, the lower the JPEG quality level, the more you butcher the image. Once done, you cannot go back without finding the original file. Level 12 on the left, 6 in the center, 1 on the right. Shown at 300% of actual size to make the artifacts easier to see.

Center image isn't terrible, but has noticeable, blurry areas. You can just make out some of the 8 x 8 blocks. Obviously destroyed image on the right. There's no way back from that.

Starting with a 9MB jpeg the TIFF (and DNG) file output is 141 MB - so they are adding a lot of something!

Nope. You still have the same numbers of pixels in the height and width as what you started with. It just isn't compressed data anymore.

I don't know why you insist on bringing up the fact the original image is not restored. That's not what I said and not what the app claims. And of course, if the source jpg is bad enough there's not much that can be done.

FWIW, DNG is just a wrapper for an underlying image format.

You can even create a DNG with a JPEG as the underlying format.

As for the app, you could just open the JPEG in Photoshop or Affinity Photo

and create a few quick scripts/macros to help "interpolate" missing data

which is all the Topaz AI app is doing. While I find many of the Topaz

tools quite useful, I find that their AI stuff should really go back to school.

I suppose they could have called it Topaz JPEG to pseudo-RAW AI.

Kurt, FWIW, the app takes a JPEG file and tries to restore the image to the quality it would have been as a RAW image using AI.