Loss of metada in PSP vX4

[ToreB]

Some searching revealed that the png format specification per Version 1.5.0 of July 2017, has added an EXIF chunk.
Specifications here:
http://ftp-osl.osuosl.org/pub/libpng/do ... tml#C.eXIf

Hope PSP very soon will incorporate this.

[LeviFiction]

That is an extension list, still not part of the core spec.
Also, the sample you provided does not include the eXIf chunk. Just the iTXt chunk. Which does contain XMP data. The XMP data contains EXIF tags in the XML

And, although you didn't need me to, i have confirmed that PSP purges that field when it saves the png. In fact it purged several images from the PNG. Here was your PNG format before and after PSP.
Before:
iTXt - text
iCCP - ICC Profile
pHYs - physical size
10 IDAT - 10 image data chunks

After:
tIME - last time edited
pHYs - physical size
gAMA - Gama correction
IDAT - 1 image data chunk

Now that I have confirmed your PNG's file format do you want a script that can backup this data and restore it? Or would rather not bother?

[ToreB]

I just referred to a thread on the subject:
https://stackoverflow.com/questions/954 ... a-like-jpg
I am not a programmer and this is a bit technical for me. I just want my photo edit program not to throw away data. PSP apparantly is not for me, and sadly I have paid good money for a (for me) useless product.
I had the idea that this forum could help me report what I thought was a bug. Apparently this is not a bug but just a badly executed program.
No need for you to waist your valuable time on me, i'll stick with Affinity Photo.

[ehume]

I just referred to a thread on the subject:
https://stackoverflow.com/questions/954 ... a-like-jpg
I am not a programmer and this is a bit technical for me. I just want my photo edit program not to throw away data. PSP apparantly is not for me, and sadly I have paid good money for a (for me) useless product.
I had the idea that this forum could help me report what I thought was a bug. Apparently this is not a bug but just a badly executed program.
No need for you to waist your valuable time on me, i'll stick with Affinity Photo.

Affinity is a pretty good program, well worth the $40-50 it usually costs. OTOH, I have been using PSP since Windows 3.1, upgrading periodically. I would miss some of the conveniences PSP offers.

Try this: use Affinity to start with your raw and .png images, use PSP on the rest. I myself handle raw with Silkypix Pro 7 and SE 8 for raw, save the results as 16-bit/pixel .tif images, which I then pick up and edit with PSP. Could I go from raw to finished product without leaving Affinity? Sure. But I really like PSP. You could handle raw with Affinity and File > Export .tiff images or .jpg images with Affinity's powerful and flexible export function, but you will find PSP growing on you. And who knows? Maybe the devs will fix PSP's mis-handling of .png images.