Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: sailor on 2019-06-05, 18:59:39

Title: [solved] Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-05, 18:59:39
Hi,

I use the photographic in Corona camera setting. When I change ISO value to brighten it doesn't update its exposure in IR. I tried F-stop, too. Checking Clear VFB between renders on didn't help either. Please help.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: romullus on 2019-06-05, 19:03:02
Do you change ISo in the camera? Is it set up to override exposure in render settings?
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-05, 19:12:26
Yes, I changed ISO in the CoronaCamera. Where is the override exposure in render settings? I couldn't find it. I attached my cam setting.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: romullus on 2019-06-05, 19:57:53
I see you're using override in cCorona cameraalready. ISO, F-stop and shutter speed, should affect exposure in IR. Maybe you accidentally launched regular render instead of IR?
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-06, 05:36:16
I don't touch the camera setting in the Render setting. I usually leave same values for both. How can I turn the override off since I want to stick to the Corona camera setting?

Exposure changes do affect saved renders in the History of IR, those get brighter but not the new one in the main panel.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: romullus on 2019-06-06, 09:27:37
What i mean by override, is that you switched exposure from global to photographic in Corona cam and now camera is overriding exposure that is set in render settings. If i understand it correctly, that is exactly how you want it to be, so you don't need to change anything here. As for why exposure doesn't change in IR, i really don't know. If you're saying that exposure changes are only reflected when saved to disk or to render history, but not in VFB while rendering, that doesn't sound right to me. What Corona version you are using?
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-06, 10:43:24
ok, thanks for your explanation.

My Corona is version 3. If I keep changing only F-stop value, it seems to work fine but after that I then change shutter speed it doesn't reflect. It looks like it even ignores those F-stop changes and go back to original darker exposure in IR.

If I Store Current VFB under History tab and got a couple of renders there, I see those ones do reflect to that F-stop and shutter speed which is way brighter, however their thumbnails remain darker.

It's strange!
Title: Re: Corona camera doesn't update after changing ISO value
Post by: romullus on 2019-06-06, 11:04:03
I don't use photographic exposure, so i'm not sure if it's bug, or just something that we're missing here. I suggest you to open support ticket, so the Corona support team could guide you through this issue.

https://coronarenderer.freshdesk.com/support/tickets/new
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-06, 11:27:18
Thank you for your help, I will check that link.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: maru on 2019-06-06, 13:52:33
Hmm, looks like it works fine here. See the attached video.
The only strange things are:
-ISO can't be interactively changed from the Render Setup > Camera dialog
-Corona Camera radio buttons are jumping randomly
Both of those things are already logged in our tracker though.

If you have already reported your issue through the helpdesk, we will definitely investigate.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-06, 15:49:30
Thanks for your video, that helped me find a clue.

At 0:22, I see you change the radio button from Use photographic exposure to Use simple exposure, minimize the Render Setup, and go to Corona Camera setting. Can you change the radio button back to Use photographic settings in the Render Setup(F11),  set the radio button to Use photographic(ISO) in Corona Camera setting, and try to see?

I had F-stop 11 at first, change to 8, and change to 4 again which is fine so far. But then with F-stop value 4 if I change shutter speed from 250 to 125 this time, it doesn't reflect with Use photographic exposure in Render Setup(F11).

Now I change it to Use simple exposure(F11), it works fine. It reflects quick when changing F-stop values only but gets slow when Shutter speed.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: maru on 2019-06-10, 13:43:04
Ok, another test. Everything seems to be fine. The only issue is that with certain settings the VFB seems to react slower.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-12, 09:01:49
Thank you for another one. I will test with the viewport IR instead of the VFB window. I use CPU, not GPU. Does it matter?
Title: Re: Corona camera doesn't update after changing ISO value
Post by: maru on 2019-06-12, 12:28:36
I use CPU, not GPU. Does it matter?
Huh?
Any rendering in Corona is done on the CPU.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-12, 18:31:10
Ha ha ha, forgot about that.
Title: Re: Corona camera doesn't update after changing ISO value
Post by: sailor on 2019-06-14, 11:25:20
I tried both viewport IR and VFB with Basic photography settings in Render Setup and both worked fine this time. It reflected quite faster than before as I changed each f-stop, shutter speed, and ISO. This is the new version 4 and it's all good so far.
Title: Re: [solved] Corona camera doesn't update after changing ISO value
Post by: maru on 2019-06-14, 15:55:19
Great, marking this as solved then!