Exiftool reduces the resolution of jpgs

[StarGeek]

sevy, would you mind sharing (or creating a new) image for all three of your steps so we can figure out the tags the hold the resolution in case someone comes along at a later time looking to solve a similar problem?

[sevy]

no problem, how do you want to receive the files ?

[StarGeek]

Got the files, thank you sevy.

I can't be completely sure as Adobe Bridge doesn't appear to show a resolution for PNG files, at least I can't find one, and my Lightroom is so old that it doesn't even load PNG files, but it looks like the resolution is in the PNG-pHYs group.  Specifically, the PixelsPerUnitX, PixelsPerUnitY, and PixelUnits tags.

Code Select Expand

C:\>exiftool -g1 -a -s -PNG-pHYs:all Y:\!temp\st -ext png
======== Y:/!temp/st/01_300dpi.png
---- PNG-pHYs ----
PixelsPerUnitX                  : 11811
PixelsPerUnitY                  : 11811
PixelUnits                      : meters
======== Y:/!temp/st/01_300dpi_et.png
======== Y:/!temp/st/02_300dpi_et_manual change.png
---- PNG-pHYs ----
PixelsPerUnitX                  : 11811
PixelsPerUnitY                  : 11811
PixelUnits                      : meters
    1 directories scanned
    3 image files read

So, to add onto the original command
exiftool -r -all= -TagsFromFile @ -*resolution* -PNG-pHYs:all -ext jpg -ext pdf -ext ai -ext png -ext tif -ext psd -overwrite_original /path/to/files/

Thanks again for the help, sevy

[Phil Harvey]

Nice.  Well done.