What keppn said about iterations is very true, and Redshift feedback is very quick most of the time,. But the same can be said for Corona, VRay, Octane, Arnold, these days. They all have interactive rendering to some degree, that allow for the careful fine tuning of materials and lights in near real time. Redshift does it well, but it can slow down real quickly with complex nodes, and it does have some weaknesses and problems compared to stronger engines like VRay that will not go away with their development cycles.
I’m speaking from my own experiences and they’re not limited, as growing numbers of clients are insisting that Redshift is part of their pipeline and that’s all there is to it. I would say that 7 of my last 10 jobs have been this way. At first it was a burden, but you get used to it like anything else.
I had a job with Apple, 3 months looking at a single scene trying to match a single reference photograph and an approved (Max) Vray version of the scene. I can tell you that for shit like Interiors, it’ll do an excellent job when pushed, especially with portals being able to push so much light into a scene. But seeing the ease with which the VRay guys matched the reference image with only a handful of lights and some beautiful material work, I found that Redshift required lots and lots finessing to get anywhere near (probably ‘50’ portal lights) the fidelity of a VRay shot - Like I said 3 MONTHS of pixel f**king for one shot… They paid, I delivered (and got numb to their daily changes after a while).
And more annoying still, touch a single dial ever so slightly in the wrong direction and your material often goes to shit, with a very finicky and sometimes difficult to dial in material system that often requires a multitude of material blended nodes to even get close to the quality of a Vray shader.
Redshift is phenomenal if you’re concepting, in the same way as Octane. You get fast results, nice renders and GPU rendering on a couple of RTX 3080’s feels lightening fast. Like any render engine, you can quickly choke a scene with too many fancy parameters. Redshift IMHO is piss poor with glass; does a lousy job at material illumination (glowy things lighting a scene), and struggles of course the same fate as all GPU renderers if you throw too much geometry at them. When you’re on a rig with 2 x 10gb cards, but also 256gb of RAM for the CPU side, big scenes, big environments require a CPU renderer, without a doubt.
So, overall, not knocking the software. It’s clearly gaining ground for it’s strengths, but it’s weaknesses are apparent and make it look very weak next to something like VRay.
Here’s 3 recent scenes that used Redshift exclusively.
And the opening segment here, rendering at 2 frames per minute: https://www.behance.net/gallery/113014017/Motion-Reel-2021