Correctly Rendering with Cycles in Blender?

I’m new to Blender, and on a Mac (see below for specs if need be). I’ve only been at it for a couple months and I’m learning it on my own. I have no prior experience with 3D design whatsoever, but I’ve made some great progress.

I am a little confused about Cycles Rendering. I was under the impression that it rendered in real time now instead of in boxes per the Blender Internal Engine… I think. I’ve never used that one. I have Cycles Render selected.

This is what I am experiencing: When I press Shift+Z I can see the image rendering in real time! Cool! But when I go to the render button (the little black camera button) and press Render, it no longer renders in real time, but in boxes on the screen, and it goes much more slowly.

Is this supposed to happen? O.o

In short, what is the proper way I should be saving my renders and making the best of cycles?

Thanks for the read. Hope you can set me straight. :slight_smile:

  • Macbook Pro 2013 13" blah blah 2.5GHz Core i5 blah blah Intel HD Graphics 4000 1024 MB bloopy blah

Is this supposed to happen?
Yes, unless you choose ‘Progressive Refine’ under the Render / Performance settings. This will however render your scene slower for the same number of samples

Not quite the right concept. And by no means “real time”.
Here’s how it works:
Cylces will give you a rough but fast preview of the current frame when you press Shit+z.
From there it will start refining the image until it reaches the number of samples determined by the Scene->Sampling->Samples tab. Every time you change something on the scene or move the preview window it will start over and re-render and re-refine the scene. The reason is fast is because the preview is showing you the image as soon as the first render samples are being computed, and also because the number of samples is low. If you increase the number of samples for the preview you’ll notice that it will render a rough picture very fast and then it will start refining for a longer time to completa all the samples and give you a much nicer picture (with less noise). The process is called, not surprisingly “Progressive Refine”. It’s designed to help you work fast so you have a rough idea of how things look without having to wait for the perfect render to be done before you can alter the scene.

When you render (pressing f12 or the render button), Cycles default setting is to divide the image in tiles, so that it can focus the resources of your hardware in a more efficient way, using all your CPU cores, and distributing the load so that each core renders one tile to the full number of samples before moving on to a new tile.
Checking the “Progressive refine” in the Performance tab will change the behavior from tiles to rendering the complete frame over and over in an additive way until all the samples are rendered, but it will be slower and more memory intensive than rendering the tiles.
It does have the advantage that you can stop the rendering when things looks good enough, but if you are rendering an animation or a sequence of frames you’d still need to wait til all the samples are rendered.

The main reason to render in tiles is that it maximizes the use of RAM and CPU time available for each tile using a “divide an conquer” approach as opposed to a full on invasion…

But none of all of this is happening in “REAL TIME”.

You can also activate the Progressive Refine check box to make the final render work more like the viewport (i.e. no boxes). Cycles renders the entire scene as a single image then goes back and keeps refining it until it meets the goal specified by the settings. It does take a little longer, but you can stop the render at any time and just save the image in the viewer as your final output. This way you can set your samples and bounces a little higher and just wait until you think the render is done and press ESC then save it manually F3. Not really useful in an animation situation but if you are just producing stills it can be of help.

Thank you for all of your answers. They were all precisely what I was looking for. The difference between the two rendering methods makes perfect sense, and now I’m aware of the time differences as well. And the correct usage of Real Time. I’m doing mostly stills, so I’ll flip back and forth depending on the scene at hand. I’m going to experiment with some simple scenes now.

Thanks to all of you. :slight_smile: I’m also impressed by the speed and thoroughness of all your answers. Not used to that on forums… I feel like I’m being spoiled. Ha ha!