Can rendered images vary between hardware?

I’m asking the below questions because I’m wondering if it is wise to mix and match computers when trying to render a project. Computer A uses the CPU and gets frames A through B, Computer B uses the GPU on frames B through C, etc.

I am wondering if, in general, since rendering is a digital process of ones and zeroes, it is reasonable to expect that the same blender file, using the same settings with the same renderer, will always look identically the same no matter what computer it is rendered on (provided of course the computer supports the render settings).

Can I expect that GPU rendering with Cycles will always result in the same rendered image as a CPU render with Cycles? I know that some GPUs support different render settings than others, but I assumed it was more like some are “missing” some rendering features, while others are providing the whole set of options. Assuming the features are supported, can you expect renders to look the same between computers?

Does a CPU render with Cycles always provide all the features as a full GPU set of options? Aside from the possibility of slower speed.

Do a test. It may depend on settings and features used during the render. I have rendered animations on multiple machines in the past and haven’t noticed a difference. This means that if there is a difference, it’s either too small to notice or gets wiped out by the video compression anyway. I would not be surprised if you did find a variation within a small percentage, but whether or not it’s acceptable for your purposes would be up to you.

Render identical frames which you may foresee problems with and compare them in photoshop/gimp.

They will differ, as GPU float point units usually have “lower quality”, less precision on some ranges, different cos/sin/log result. Not that big difference to have very visible artifacts, but sure differ in pixel to pixel comparison.

That makes sense, thanks for pointing it out.