# Image increasingly dark - 1.4 RC7 **URL:** \ **Category:** Issues\ **Created:** [May 16, 2016, 11:39am UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717 "2016-05-16T11:39:29Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Alexandre\_Besson\_1](https://avatars.discourse-cdn.com/v4/letter/a/4bbf92/32.png) [@Alexandre\_Besson\_1](https://forums.chaos.com/u/Alexandre_Besson_1)\ **Post date:** [May 16, 2016, 11:39am UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/1 "2016-05-16T11:39:29Z")
Hi, I have a strange issue, my image becomes increasingly dark each render. Thanks ![DARK ISSUE.jpg](https://europe1.discourse-cdn.com/chaosprd/original/3X/9/1/91d6af1c743e93d76037f9eb8748e0cefce700a4.jpeg) ---
**Author:** ![Alexandre\_Besson\_1](https://avatars.discourse-cdn.com/v4/letter/a/4bbf92/32.png) [@Alexandre\_Besson\_1](https://forums.chaos.com/u/Alexandre_Besson_1)\ **Post date:** [May 16, 2016, 11:45am UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/2 "2016-05-16T11:45:05Z")
some precision: When I increase exposure after a render, the next render becomes dark again. ---
**Author:** ![maru](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/maru/32/15975_2.png) [@maru](https://forums.chaos.com/u/maru)\ **Post date:** [May 16, 2016, 1:29pm UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/3 "2016-05-16T13:29:36Z")
Hmm… Could it be this? [https://coronarenderer.freshdesk.com/support/solutions/articles/5000517899](https://coronarenderer.freshdesk.com/support/solutions/articles/5000517899) Can you set MSI to 0 and see if it behaves the same way? Maybe you are using a Corona Output map somewhere? ---
**Author:** ![ledoudoualex\_1](https://avatars.discourse-cdn.com/v4/letter/l/a4c791/32.png) [@ledoudoualex\_1](https://forums.chaos.com/u/ledoudoualex_1)\ **Post date:** [May 16, 2016, 1:49pm UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/4 "2016-05-16T13:49:46Z")
I’m having the same problem. The only way to achieve a convincing result is to use the 0 MSI value. But it’s not resolving noise a all ! doing some test with the 1.3 / 1.4 Dailybuild NOT RC to see if it worked … ---
**Author:** ![maru](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/maru/32/15975_2.png) [@maru](https://forums.chaos.com/u/maru)\ **Post date:** [May 16, 2016, 1:53pm UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/5 "2016-05-16T13:53:02Z")
Guys, be sure to read the article I linked. If that’s the reason then this is EXPECTED behavior. ---
**Author:** ![ledoudoualex\_1](https://avatars.discourse-cdn.com/v4/letter/l/a4c791/32.png) [@ledoudoualex\_1](https://forums.chaos.com/u/ledoudoualex_1)\ **Post date:** [May 16, 2016, 4:16pm UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/6 "2016-05-16T16:16:59Z")
As we’re working together, i’ll answer for the both of us. We didin’t touch the MSI until you told us. The problem appeared BEFORE (with default 20 MSI value) … It only happens in a specific interior view as the others cams (interior shots included) gave us results we were expecting. We already have done a lot of images with Corona without any problem - this is why we would like to understand what’s really happening. In this particular case, it looks like the exposure control is virtually locked and we couldn’t succeed with 1.3 / Daily builds / non-RC neither. Adding a portal resolve the thing a little bit (we gain like 1-2 exposure levels) but the image deseperatly looks dark ! In a second time, AFTER reading the article you gave us, we tried changing the MSI to 0. The image appeared correctly (nevertheless a bit noisy) and we could reach the expected result playing with EV - trying other values didin’t work at all. So, the new question is : is that normal having to play - when the light is rare - with two parameters (MSI + EV) instead of a single one (EV) or is that a problem ? thx. ---
**Author:** ![maru](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/maru/32/15975_2.png) [@maru](https://forums.chaos.com/u/maru)\ **Post date:** [May 20, 2016, 3:13pm UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/7 "2016-05-20T15:13:19Z")
> [@Alexandre SCELLIER](#): > > We didin’t touch the MSI until you told us. The problem appeared BEFORE (with default 20 MSI value) … It only happens in a specific interior view as the others cams (interior shots included) gave us results we were expecting. We already have done a lot of images with Corona without any problem - this is why we would like to understand what’s really happening. If “the problem” is what is described in the article I have linked earlier, then it is, again, EXPECTED to happen with the default value of MSI 20 an it will NOT happen with MSI 0. However, I am not sure what the issue here is, so I am just guessing. > In this particular case, it looks like the exposure control is virtually locked and we couldn’t succeed with 1.3 / Daily builds / non-RC neither. Adding a portal resolve the thing a little bit (we gain like 1-2 exposure levels) but the image deseperatly looks dark ! I am not sure if we are talking about the same renderer here. 😉 Portals should never introduce any exposure changes in Corona. In fact, they should introduce no changes at all, except for sampling (noise, image quality). > In a second time, AFTER reading the article you gave us, we tried changing the MSI to 0. That would confirm that this really is an expected behavior. > So, the new question is : is that normal having to play - when the light is rare - with two parameters (MSI + EV) instead of a single one (EV) or is that a problem ? Changing EV AFTER an image is rendered may sometimes produce different results than changing EV BEFORE the image is rendered, as described in that article. ---
**Author:** ![Ondra\_1](https://avatars.discourse-cdn.com/v4/letter/o/50afbb/32.png) [@Ondra\_1](https://forums.chaos.com/u/Ondra_1)\ **Post date:** [March 29, 2017, 7:16am UTC](https://forums.chaos.com/t/image-increasingly-dark-1-4-rc7/133717/8 "2017-03-29T07:16:26Z")
expected behavior (unfortunately)