Photoshop 32 bits PNG

[isabelleg58215236]

Hello,

I have a file that is 300 DPI 4000X4000 pixels 32-bit. I want to export it in PNG-32 (or even 24!). I do "export as" export PNG format without ticking the box 8-bit and when I bring back my PNG file in Photoshop, it is 8-bit! Even when I see it in Bridge, it tells me that this file is 8-bit. I have watched several forums since yesterday and there, I am totally without resources ... Thank you for your help!

[Test Screen Name · Accepted solution]

I think you are mixing up two different kinds of "32 bit", not surprising really, it's very confusing.

I assume your current image is RGB and shows Image > Mode > 32 bit. This is a special kind of working, not stored in ordinary image files. This is 32 bit per component - 32 bits for red, 32 bits for green and 32 bits for blue. A total, in fact, of 96 bits for each pixel.

Now, when people talk about 32 bit PNG what they mean is it is 32 bits for each pixel: 8 each for red, green and blue and another 8 for "alpha". 24 bit PNG is the same without the alpha. So, if you export to PNG your 32 bits for each component is turned into 8 bits, and when you reopen it that's what you get. This is plenty for delivering graphics to the web. When you reopen a 24 or 32 bits (per pixel) PNG in Photoshop, you'll correctly see that you now have an 8 bit (per component).

Of course, you lose lots of info from your original file, which is why we always save as PSD for editing later.

[isabelleg58215236]

Thank you so much for these precisions !!! Indeed, it's easy to get lost in this world of PNG! 😉 This PNG is for printing clothes, so I want to make sure the picture is clear! So, if I understand correctly, I have to put my file in Image> Mode> 8 bits and after I export for the web in PNG-24 and the file will be ok and of good quality? The 8-bit that appears in the info next to my file when I bring it back to Phoptoshop is simply to tell me that each layer (R-G-B + Alpha) on 8-bit each? Thank you in advance!

[davescm]

No need to use Image mode to change the bit depth. The "export as" process will change the bit depth for you. The rest you have picked up correctly

Dave

[isabelleg58215236]

Nice!!! Thank you very much ! 🙂