I was about to render a modelled scene properly for the first time, I double checked all the render settings to make sure there was nothing unnecessary being rendered. Also making sure that the individual frames were exported in JPEG format and the quality was at HD 1080. The first scene I rendered was the time-lapse scene which consisted of a total of 120 frames. I started the render at around 3:30pm and I knew it would take longer than a few hours to render the scene so I spoke to Steve from IT resources and he said it would be okay for me to leave it rendering over night to avoid the batch render cancelling as they computers shut off automatically at just after 9pm normally. He was able to change the permissions on the particular computer I was rendering on to stay on, and the scene was able to render throughout the night. I came in at around 9:30am the following day and the scene had rendered around 17 frames during the 18 hours it had been rendering, so it was taking around an hour per frame. It was too slow to be viable so I spoke to Mat and he said it would be okay to render across several computers, since on this particular day nothing was timetabled and the room was virtually empty. I loaded my work across three separate computers, dividing the work into thirds and allocating 30 frames to each of the computers. After setting everything up I went back to the IT resources and spoke to Mike, who said it would be fine to change the permissions on these computers as well, like Steve had previously done for me. I got the unique computer number from the towers of each computer and he was able to do it remotely from his office. Unfortunately after spending some time monitoring each of the computers I found that one continued to crash so I had to cut it down to two and render off of those instead of all three.
The initial environment shots I found took the longest to render because they essentially comprised every element that had been modelled, including the heavier elements such as the grass and fence, both made of polygons and together make up around two thirds of the scenes total content in terms of polygons. Due to this, I tried to get these scenes out of the way first while I worked on other less detailed scenes, such as the action taking place inside the barn. This ended up being a fairly efficient process and no time was really lost when you consider that the rendering took place in the background and luckily due to the available resources, could be left to render whilst other progress could be made on the project in other areas.
One thing I did do before each scene was rendered was render still frames at various points throughout the sequence, at a low quality so it didn't take up to much time. The reason for this was so I could look at the lighting and camera angles throughout the sequence and make any small modifications before the final scene was batch rendered, as I wanted to prevent being unhappy with how the frames looked or for example, how the scene was lit after half of the scenes frames had been rendered, thus wasting valuable time. I tried to be as thorough as I could be when setting up scenes to render and testing aspects such as the lighting. For various scenes I even changed the 'physical sun and sky' from a directional light to an ambient one, and changed the intensity to make it so there was a faint glow of white-blue light coming through the gaps between the planks that make up the barn. I found this added a cinematic element and looked a lot better than before when the outside was almost completely black, making the scene feel a little lacking overall. Another lighting consideration that I changed scene to scene was the interior lighting of the barn. Depending on the angle of the camera and the time of day outside the barn, the interior could become very dark and poorly lit. I decided to change the 'decay' on the lights to linear rather than quadratic, meaning there was more light in the scene. However, to balance this further I did have to change the intensity from 20 to around 2 - a tenth of the original intensity in order to compensate for the change in the decay settings. With this project in particular and the nature of the way rendering and production is conducted I made a special consideration to make sure that there was continuity from scene to scene. What I mean by this is that since each scene is created individually in terms of animation and direction, and then rendered by itself, it was important to make sure that aspects such as the time of day outside made sense when the various scenes are finally stitched together into a final sequence.
I ran into several problems whilst trying to render various scenes throughout the project. Some of which were quite easy to solve and others not so much. One of the strangest problems I encountered when trying to batch render a scene was that the rendering didn't complete and essentially said that rendering was completed without rendering any of the individual frames. Wing also encountered this problem whilst attempting to batch render the 'bouncing ball' scene. I believe the issue was with mental ray, but I never actually discovered the cause of the issue. I read through a lot of forum posts and a lot of the contributors suggested different causes to the problem, a lot of them didn't apply to mine and Wing's situation though. This particular problem first happened to me when rendering the scene with the poster affected by the wind. At first I thought it could be a memory issue, but after playing around for a couple of hours it was working again. It's strange because the main feature of the scene I was adjusting was the lighting, specifically the physical sun and sky. This leads me to believe the issue was with mental ray, or perhaps the translation to mental ray. One good thing that came from having to troubleshoot these issues is that I learnt how to use the script editor to try and discover the source of problems that were occurring. This will help me a lot in the future I think when I come across various issues.
Overall, the process of rendering in this was an invaluable experience in terms of time management, planning and in a way organisation. I found that it was vital considering the length it takes to render different scenes that it is implemented in an efficient way so as to waste as little time as possible. It showed me how important it is to make sure a scene is ready and to an extent before rendering for real.
No comments:
Post a Comment