Unusual screen render issue

[R Reynolds]

I made the transition to WIn10 on my PC at the beginning of June and installed A:M ver.18.0m shortly there after. I've had almost no teething problems for the last two weeks but this occurred after yesterdays' Windows update which may just be a coincidence.

 

This is a screen grab of a realtime render and a good approximation of a final render.

 

This is a screen render in Render Lock mode.

 

This is a screen render in Render mode.

 

I upgraded my Nvidia graphics drivers and re-installed ver. 18.0m without solving the problem. This doesn't happen in ver. 17. I see that Hash Reports is currently broken so I'm open to suggestions.

[robcat2075]

V18p is out. Try that next.

[Guest]

Installed v18p...same symptoms. And since we're talking about screen renders; I found it disconcerting in v18 (before this issue arose) to have the last screen render, stored in a buffer somewhere, show up as I draw a box around the part of the screen I'm trying to render. I would prefer the box to be see through.

[robcat2075]

Ideas, just to try...

 

-OpenGL3 - OpenGL toggle

 

-Help>Reset Settings

 

-Set graphics driver "acceleration" to its lowest level

 

-Roll back the Windows Update. How to rollback a Windows update

[Guest]

 

-Help>Reset Settings

DING! DING! DING! We have a winner!

 

Thanks Robert.

 

So as I was putting the settings back to my preferences I managed to reproduce the "feature" (not a bug).

 

It's related to the Preview Gamma in the Rendering settings.

 

 

The defaults for Desired and Current Gamma are 2.2. Since in PSPro's histogram functions a gamma = 1.0 is the most neutral/natural, I jumped to the presumptuous conclusion (without doing any testing) that those default values must be mistaken.

 

Mea culpa.

 

Now I'm curious as to why being able to change this gamma value is useful to anyone.

[robcat2075]

"Gamma" has always confused me.

 

I know what it means bu if I calibrate my monitor to... whatever some gamma calibration test says i should make it, the artwork I produce in that environment is way too dark when other people view it on their monitors.

 

As far as those 2.2 settings in A:M... if the art you are creating in A:M now under those settings looks appropriate out of A:M, in other programs and browsers and on other people's screens, leave those settings as they are.

[Fuchur]

I'd say you need to calibrate you display first. With that, you could get a better experiences from that, but it always is different for all of us anyway...

http://www.cnet.com/how-to/how-to-calibrate-your-monitor/#!

 

This is only a software calibration... a better one would be a hardware calibration like this one:

http://spyder.datacolor.com/portfolio-view/spyder5studio/

 

The problem with all that is, that people will never have the same calibration (it is not only about the calibration profile but it depends on the age of the display, the quality of the display, the manufacturer, etc.)... you can get pretty close with the hardware once, but only for people who use the hardware calibration tool and presets you used too.

For all the others, it will not be the same and there is even more to this like: Who says, that yellow looks the same for you and me? Maybe we do not have different color taste at all but we receive it differently in our brains and because of that, I like yellow and you don't (or visversa... this is only an example).

 

It really is hard and an very complicated topic...

 

See you

*Fuchur*

[robcat2075]

 

This is only a software calibration... a better one would be a hardware calibration like this one:

http://spyder.datacolor.com/portfolio-view/spyder5studio/

 

 

I actually have a previous version of that. It hasn't worked since I moved to Windows 7 but when I was on Win2K I used it to "calibrate" my monitor and that's when the problem started.

[itsjustme]

 

-Help>Reset Settings

 

Now I'm curious as to why being able to change this gamma value is useful to anyone.

 

 

 

Here is a very quick explanation as I understand it. Hope it helps.

 

 

----------------------------

EDIT

----------------------------

 

I forgot to mention that the Gamma render setting for the images was "none".

DesiredGamma.mp4

linearization.zip

[Guest]

Thanks David, that was helpful. It was also nice to see your screen going foggy and hang during a quick render. I thought it might be peculiar to my PC.

[itsjustme]

Since my explanation isn't as comprehensive as I would like, here is a video explaining linear workflow and the gamma correction associated with it: http://greyscalegorilla.com/tutorials/what-is-linear-workflow-and-how-can-it-help-your-renders-look-better/

 

What is not currently part of A:M, is a button to automatically linearize the 8bit images being used and the material color picker (I've been thinking about making a feature request for a checkbox in the "Tools/Options/Rendering" dialog)...you would have to linearize them yourself before rendering. Also, I didn't mention that you can change the A:M output gamma to 2.2 if you are rendering out an image that you don't plan on doing any post processing on. Of course, it is best to keep everything linear until the final image.