Why jpf files instead of jpg?

[spotter27]

Why does photoshop save files as jpf when I ask it to save as jpg. The only app on my Windows PC which views jpf files is photoshop. No other app opens this type of file )see message below). jpt files are not supported. How do I get around this and make it save as jpg?

[Stephen Marsh · Accepted solution]

It sounds like the current file attributes aren't supported by JPEG (not flattened, or has alpha channels, or is not 8bpc) and you are using Save As rather than Save a Copy – or you don't have Legacy Save As enabled in your File Handling Preferences. You would then be mistakenly selecting JPF as JPEG isn't listed as you expect.

JPF is JPEG2000 format which never gained widespread adoption, despite it being technically better than JPEG.

[spotter27]

I save as JPEG 2000 And it actually saves as jpf. Never happened before. Just since updated. Damned annoying as nothing other than Photoshop opens this format.

[Stephen Marsh]

JPEG2000 IS JPF, J2K, it's NOT JPG/JPEG (which is really JFIF).

[Stephen Marsh · Accepted solution]

Again,  you need to either Save a Copy – or set Legacy Save As in your Preferences > File Handling to get to JPEG. If your image is 32 bpc then you can use Export As or dupe the file and convert to 8 bpc (if unsure use gamma 1, exposure 0 toning).