I now think John Beardsworth is right. More testing on a range of images with both luminance and colour noise in the shadows and the sky shows me that my initial impression was mistaken. V4 alone does not seem to make a difference in either the shadow detail or highlight fall-off. Apologies for the red-herring.
Perhaps THAT's why Adobe included the comparison tool: to show that the change (which is automatic once you move any of the 'Basic' tools or the Tone Curve or any of the local adjustment brushes) is invisible.
Well, don't feel too bad.. You weren't the only one that was being fooled by that buzz word "process version". I too thought I saw the same things you were seeing. But after some more checking it just seems to be more a matter of how directional some LCD's tend to be.
BTW, I think that comparison 'tool' has been there for prior process version changes as well.. All it does is automatically change to comparison view, set the 'before' side to the prior step, and the 'after' side to the current step.
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OT (aka: can't figure out how to work it into other current conversations.
):
A downside for me is that I replaced the 2015.10 version I had to revert back to from 2015.12, that worked with my AMD for GPU acceleration (I
still can't find release notes that would have stated 'known issues', for Classic).. It has still not been fixed by Classic.However, in regards to that - 2015.12 wasn't nearly as slow as Classic is without GPU acceleration. Classic is a pure snail in comparison - many times several seconds for a change to show up.. So now I'm kinda screwed.
And I won't be able to afford a new laptop/computer for a LONG time to come.
Sooo... Given that, as well as the change to RansomWare, on top of the indicative/predictive(?) 'hard to find anything about Classic on Adobe's website' issue -- I'm kinda out while I consider on whether to switch to something that's not going to be RansomWare. Adobe
****ABSOLUTELY NEEDS**** to offer an option to keep a current snapshot if deciding/needing to stop paying the ransom.. One where the edit and map modules still work, of course - say, after having subscribed for such and such a time period.. I'm sure someone smarter than me could figure out the details. Only then, will people feel a bit more confident in sticking with Adobe at this point. I'm currently on CC, but I think it's thoroughly despicable how they've reneged on their 'promise' of keeping a perpetual version - that was always a safety net for me until now.
The biggest reasons why I wouldn't switch to something like C1 [right now] is the horrendous catalog speed, no scene-referred HDR and panorama [DNG], no map module, and lousy support for DNG. There are many others, of course, but those are probably the biggest for me - as being on the serious amateur/hobbyist side.There's also ON1 raw and ACDSee, but there are similar issues with those. It's tough deciding, when all one's past images are already edited in the Adobe non-destructive engine instructions - of course the same could be said if I was using one of the others.
<sigh> They really NEED to make it possible to keep a current snapshot if they're going to switch to pure unadulterated RansomWare.