Redshift or Arnold- GPU or CPU

Redshift IS fast but from what I have experienced the TFD render quality is just not up to Arnold, it takes longer, far longer to tweak and get the settings that give the look that approaches the quality of Arnold…and it is not that much faster than Arnold on TFD VDB’s. It also has the added advantage of loading bcfs much faster than RS thus doing away with the need to do the arduous conversion ( a point that becomes mute with Reactions)
Now my cards are very low level in today’s world, a 1070 8 GB and a Titan 12 GB on my I7 3730 6 core. I have a dual xeon as a render slave which renders out at roughly twice the speed of the I7.
Now forgetting the Xeons if I wanted to double my render speed using RS I would probably have to add at least 2x 1070 cards or maybe one 3080 though I doubt very much if a 3080 is = to a 1070 and a Titan. The draw on my power supply will ramp up and at 650 W i am not sure if it will handle it though the Xeon rig would having 1000w+ power supplies I could probably get the 2 x 1070’s for around £1000. Now if I bought or built a new 32 core Threadripper box and added one of the cards to that, and used a bog standard cheapo card for the Xeon which I have laying around, I will get a machine that would be at least 6 x faster than my I7…faster CPU’s faster Ram, better motherboard etc. The price ? I would imagine I could build a box for under £2000. Add that to what i already have and I now get at least 9x my render speed.
Another advantage is wear and tear. With RS if your card goes down your rendering ceases and you need to lay out for a new card. The chances of several components breaking on a CPU rig are slim and I have NEVER had a CPU fail - famous last words- nor RAM for that matter. Hard drives and very rarely power supplies are what tends to die and again that is very rare.
Arnold is FAR easier to configure and use, give stunningly beautiful renders , and has no issues bailing out due to lack of memory.
The ONLY reason i lean towards Redshift is the speed at which I can knock out ‘OK’ renders…but I want more than ‘OK’…if it’s good enough…it isn’t. Now for look dev I could use the GPU’s on Arnold, it is still too flaky for finals but when it stays stable it does give great GPU renders. (VDB Only)
I do have issues with some anti alias features on geometry with Arnold, RS renders beautiful smooth images but I think that is a learning curve.
Ideally I would use a combination of RS and Arnold !!
Of course all this becomes a no contest when you simply cannot get hold of the latest cards and second hand ones are likely to be well hammered.

3080s are advertised at around £2000 in the UK and are nearly always out of stock.

Redshift is supposedly revamping their volume rendering now. Volume displacement, multiscattering and light linking should help out quite a bit

I just cannot get that crisp look I can get in Arnold and TFD and the time spent getting close is better used simply setting Arnold up and rendering. RS seems to have an over smooth CGI look though I suspect I do like the Directors look…that sharp crispy fire they love that is rarely seen in real life. But RS seems to render explosions far to cartoony for my liking and if needed the Arnold renders can be blurred/smoothed to taste.

Arnold is also a lot cheaper at £35 a month.

Arnold i still best emission volume renderer on the market <3
Anw what your issues with some anti alias features ? Can you tell more detail ?

Kitbash buildings in the distance, the edges flicker when the camera is animated, increasing the filter width helps there but it is global. I suspect increasing DOF may solve it however I am sure there is a better way. Arnold is just a more crisper render out of the box than RS.

Oh no, don’t use Arnold DOF, use lentil DOF for Arnold - best DOF rendering tool on the market, and it’s just for Arnold render:


However until I can get at least a 32 core and /or justify the expense of render farms my 2 GPU’s are best used with RS…at the moment Arnold is OK for stills but takes too long to render out flicker free on my rigs and there is the hassle and overhead on net rendering when my 2 GPUs sit happily in my I7 box. RS just does a smoother AA out of the box I can use the Xeons for such things as bcf to vdb conversion until I go full Reactions based.

I completely agree with you on Arnold. I had been using Octane for almost 8 years and switched to Redshift about 5 years ago as more of my Agency clients were integrating RS into their production pipeline. Then last year as Arnold GPU started to gain parity with its CPU counterpart I gave it a look for the first time. I knew Arnold had a great reputation but had not considered it as it was CPU based and at that time I couldn’t imagine going back to CPU rendering.

I tried out Arnold and was completely blown away with how beautiful the final frame look with a minimum of fuss. Unfortunately, Arnold’s GPU counterpart still is missing some important features such as trace sets and better control over where samples are going. Only AA is only supported with adaptive sampling in GPU mode ATM.

That said, my primary workstation has a 3990x 64 core CPU and I have found it to be about 25% of the speed of an RTX 3090 which given the quality and time savings I experience during look dev and scene development with Arnold is worth it, especially if I have jobs with a little breathing room on the deadline. This has me reconsidering CPU rendering and says volumes about how impressed I am with Arnold as I’m now considering ditching my two GPU based render nodes. Nodes mind you that have a total of 8 x 3090s. Once prices come back down for the 3990x I plan on ditching these 3090s for two more 64 core 3990X based setups. Funny enough, I only got the 3990x because Houdini scales nicely for many of it’s sims with more cores. I never Imagined it being something I would use for rendering.

I just got off a feature and used Arnold for the first time in a larger scale production and my lord, the way it handles light and it’s ease at creating setups to easily match backplates made it an absolute joy to use. I also second Sup Nguyen’s suggestion on Lenti - it’s a bidirectional camera for Arnold that has gorgeous bokeh and is much faster than the standard Arnold camera at cleaning up DOF. It also supports built in chromatic aberration and has a bunch of great lens presets built in so If you ever wanted to match a Cooke Panchero 1920 you actually can select that lens as well as two dozen or more other lenses.


Lentil is fantastic!

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Arnold gives the BEST QUALITY render, even on my interior test with 100 bounces.
But that’s QUALITY, not speed. Best speed thing that Arnold does good, is volume render ( and you have to know how to do it ). With 100 bounce and 24 cores, a explosion test of mine only get 30 minutes and result is so clean. So, if you want a renderers have speed + good quality, I recommend you to buy 3Delight and Corona, then I’m sure you will be shocked because 3delight is about 30 - 50 times faster than Arnold and Corona is 100 - 300 times faster than Arnold depend on complexity of the scene.

Specially, 3Delight have insane roadmap on future but they are prioritizing development for Houdini and Maya because user base number of 3Delight for Cinema 4D is too less. By buying it, developers will understand that there are still customers interested in 3Delight for C4D and they will focus C4D again. I’m sure that you will be insteresed.

Link download 3Delight for C4D: 3Delight

3DL discord :

Hey there!

Love volumes in Arnold - especially having access to volume displacements - and I agree it’s quick to get clean results especially over other unbiased engines like Octane. Octane may be faster but by the time you get it as clean and detailed as Arnold there isn’t a huge wait difference in speed to merit the loss in IQ. Same goes for Redshift.

I have actually been playing around with 3Delight! At first I was concerned as the material system seemed too simple but you can actually do a lot with it and I have always loved the look of Renderman. The one button ease of accessing a farm is pretty cool too. I’m definitely keeping an eye on this one. Works great in Houdini too… although TBH I don’t do a lot of final frame stuff in Houdini, just sims.

I may have to circle back around to Corona one day. TBH there was something about the look I just didn’t love but maybe it had more to do with the project I was using it for at that time.