bollili
I am using redshift for quite a while now and I like it. It's fast, the houdini integration is really good and feature wise, it suits my needs.
I am a freelancer with a single workstation and three nvidia gpus. Mostly no USD/solaris. No heavy stuff for the most part.
I would like to hear what you guys think about switching to karma XPU. What are the (dis)advantages in terms of speed, tweaking and ease of use?
As I am no render expert at all, I always liked redshift's autosampling feature. Afaik, this is not yet implemented in Karma, right?
What else should I be aware of?
Cheers
I've been running quite a few different tests / scenarios with Redshift vs. XPU, and I wouldn't switch from Redshift quite yet. Karma has been crashy, buggy, lacking in features, lacking in documentation, and harder to use than Redshift for me thus far. The devil is always in the details, so I'll give you some examples:
Crashy:
* Yesterday I crashed around 8 times and had one hard reset where my GPU froze. If I spend a whole day shading in Karma, I would expect the same.
* I've noticed that Karma will gradually slow down as I'm building shader trees. The only fix is to reset it occasionally by going to the Houdini GL --> dropdown --> reset Karma
Buggy:
* Mtlx Ambient Occlusion doesn't work for me.
* You can't layer multiple materials together with a mtlx mix node
* I've run across major freezes with motion blur.
* Color management is inconsistent depending on where you decide to preview / export your images.
Lacking in Features:
* Karma doesn't have nearly the same variety of noises that Redshift does. This can make a huge difference in shading workflows that need to take advantage of hi-fidelity detail that doesn't look like a perlin noise. You can hack noises, but at that point you're just creating your own algorithms, and that won't come close to touching the artistic quality offered by Maxon noises. Besides, artists don't have time for that. That's what artists should pay software devs for.
* Many basic functions are missing in Mtlx nodes. For example, in the tri-planar node, you cannot scale, rotate, or offset your projections. Ambient occlusion doesn't work, and even if it did, the node doesn't have any features which would allow you to control things like spread angle, remap the values, etc...
* When it comes to SSS, redshift provides you with the option of random walk, ray-traced diffusion, and point-based diffusion. Karma doesn't offer you those options.
* Plus, there's a lot of other misc. things that come with age that Karma has yet to incorporate. For example, you won't find a car paint shader with Karma, but Redshift you have lots of tools there for layering multiple clear coats, adding specular flakes, and dealing with that specific situation. Redshift has the advantage of being in the game longer than Karma has. Karma, as a render engine, is still green - Redshift is more mature.
* No PostFX options... which is nice to have when you're time is in a pinch and you need to get a render out quickly.
* Karma is still new, and it will take awhile to catch up to some of the latest tech. For example, Redshift just added support for Transmission BTDF shadows. I haven't tested this in Karma (and maybe it's there) but I doubt you'll find the same thing because SideFX has been trying to catch up with basic features to make a brand new render engine.
Lacking in Documentation:
* Just try to pull up some Mtlx nodes, you won't find much.
* Motion blur documentation features scattered ideas that shoot in different directions, don't provide you with the best (or any) examples, and seem to be written with multiple ideas in mind which makes it confusing to read.
Harder to use than Redshift:
* Being that you're a solo/freelance artist, I don't think you'll see as much benefit with USD. USD can add a lot of complications and a significant learning curve. I wouldn't underestimate the gravity of that when you're faced with tight deadlines on a freelance project. There's a lot of complications to USD, and Pixar, the developer of USD, is used to deadlines that are much longer than your average freelance artist. That being said, simplicity isn't the highest virtue with USD, and having the option to bypass those complications with Redshift is a big advantage to a freelancer who needs as much simplicity as possible to remain fast.
* I think it's a big deal to have a mismatch between your viewport preview render and the final USD information that gets processed when using the USD Rop. It's really easy to make a viewport override, forget that you did that, make a bunch of decisions based on those overrides, and then come to find that it doesn't match the information that's sent to your ROP node.
* Backplates can be a little tricky to manage at first because you need to figure out what blend of viewport options and light overrides will provide you an accurate assessment of your scene.
* Redshift has a brilliant feature that lets you select "low" "mid" and "high" quality render presets. It then goes into your scene, figures out what you have going on, and makes all sorts of intelligent decisions depending on the quality you're after. That feature is fantastic for a freelance artist who may not have the time to dial in all the optimizations required for those different types of renders. Karma currently lacks that feature.
Speed:
* I've found that the speed in Karma still suffers quite a bit compared to Redshift depending on the feature at hand. Thus far, I find that Karma gets bogged down by indirect volume samples, displacements, and motion blur moreso than redshift does. I'll have to do some more tests to really confirm that, but so far, that seems to be the case.
-------------
-------------
In conclusion:
I really do love the idea of Karma being a replacement to Redshift, but I don't think it's close right now if your top priorities are ease-of-use, stability, and features that add quality to your workflow. I'm not a fan of Maxon buying Redshift either. In the long run, I'm hoping that Karma steps it up a few notches, but it's going to take time, and it's not there yet in my opinion. That said, I'm still testing it, but I wouldn't jump ship right away if I was in your shoes. You might be right about the decision of switching over eventually, but you need to be careful about the timing of that when you have tight deadlines as a freelancer.
Good luck,
- Tyler