P: Inconsistent JPEG quality with 1-7 slider in Export As

My results are identical. And not evaluated visually but by pixel by pixel comparison. The latest release, on latest Mac OS.

7, 12 and 100% are different scales indeed. Whatever I use that defines max quality, the only way to set such at test, produce identical JPEGs. I don't again see the problem.

The problem is that the results aren't identical, which is obvious if you just look at my example. The 1-7 slider does not scale to 100% quality when using Legacy Quick Export. It does do that when using the normal Quick Export, but not when using Legacy.

The maximum quality setting when using Legacy is 7, just like it is when using Normal. But "7" seems to mean something different to Legacy than it does to Normal. And since the UI won't let me set the value any higher than 7, even when using Legacy.

Saving settings after checking "Use legacy" and then re-opening the settings dialog doesn't make that slider go any higher than 7. Closing and re-opening Photoshop doesn't make that slider go any higher than 7.  That is what makes this a bug.

I get the problem now. With legacy export on, the quality setting in Quick Export isn't correctly interpreted. It's treated as 7% or something, very low quality, and size correspondingly small:

Turn off legacy, and there's no problem.

I'm confused as to what is 'wrong' here. 

Again, when I set the max quality for a JPEG, with differing scales, the results are identical. 

Ah crud, the forum software heavily compressed the JPGs I just uploaded. To see the quality differences, you'll need to click on it to view the original in a lightbox, rather than looking at the image directly in the comment.

Here's three images that show off exactly what's wrong:

Original PNG:

Normal Quick Export as JPG at Quality 7:

Legacy Quick Export as JPG at Quality 7:

(Notice the extreme JPEG artifacting along the edges of the green field areas, which doesn't exist in the other jpg)

The ONLY setting I changed between those two exports was checking the Use legacy "Export As" checkbox in the Export Preferences.

It seems likely that the Legacy Export As system is using the 1-7 slider in the same way that it used to be using 0-100 slider. So when it sees "7" it's like "Wow, this guy really wants to heavily compress that jpeg!" instead of "Ah, this guy wants a full quality JPG!"

> Do not use legacy, the scale isn't percentage and maxes out at 7

That's the bug. Legacy Quick Export didn't do that until the latest version, which replaced the 100-point slider with a 7-point one.

Or are you claiming that it's intended behavior that Legacy Quick Export can't output at better than 7% quality? Because I sure hope that's not what you're saying.

A value of 7 and 7% are simply vastly different. And to be expected. 

When I toggle on and off the Legacy option in preferences, and no need to restart, the differences are pretty clear:

Use Legacy: scale in percentage up to 100%

Do not use legacy, the scale isn't percentage and maxes out at 7

Exactly. This bug is specific to Legacy Quick Export. Not the new one.

The reason I use Legacy is because I always want to export to the same folder as the file I'm editing, and the new Quick Export doesn't do that (it always defaults to the last folder you exported to). If you set up an option to make the New Quick Export always default to the current folder, that'd also work for me, as I could stop using Legacy.

Ah, that may be it: With "legacy" checked (which I don't have), the new 7 may be treated as the old 7. Haven't tried that yet.