fprime compare to kray

[jdomingo]

Hi
i know fprime and kray are different rendering engine so therefore i will be getting a different result. but for what i can see from my test, i kind of like the result from fprime than kray. please see attached image. kray has low default settings. maybe it can be achieve in kray but how, can anyone show me how? you see on fprime test, the corner of the box has good contact shadow and it defines the corner and the box has some kind of occlusion going on as seen on the surface of the box meaning fprime is not flat as compare to kray. as i said maybe it can be done in kray, please can somebody show how? it is a simple box radiosity test and fprime seems simple to adjust and nice instant preview and i like the result. kray please let me know how to acieve this result in simple way? thanks

[Janusz Biela]

Thats the point. Is no big difference between FPrime and Kray, even V-Ray...why? becouse both use the same "The mathematical model of behavior of photons".
Now small correction for Your question. You compare QMC FPrime render with Photonmaping Kray render....This is totally two difference ways of render. QMC is no interpolation method! So You can not compare. FPrime has only this engine (QMC) ...why only this? Answer is easy: becouse is very easy write down engine without interpolation. (I remind you: V-Ray starts in 1997 and appeared in 2001 but with bucked of bugs....Kray appeared in 2005 or something that, and still both are under construction...) QMC id GREAT but has only one problem : SPEED RENDER and NOISE, becouse is direct method of render. Turn ON QMC in Kray (just uncheck CACHE IRRADIANCE) You will receive the same render, even faster. Second "mistake in your question is SCENE.This is basic scene which does show NOTHING. Is as comparing basic car and Porshe in city...no difference.But if You will render interiors or heavy scenes , difference can by HUGE (even 20-50 times faster in Kray with quality which FPrime can not achieve).
Imho Fprime is completly archaic render comparing to Kray...and realy I do not see any real reason why Worley continue this engine (for real I know, good render engine need a few years for coding, so they should start from the beginning...but we know now is big competition between new engine renders to absorb next . V-ray, Kray, Maxwell, fryrender, Moodo) and they are very good.
FPrime was good many years ago...but know rule new moderns engines.
Returning to FPrime, this engine even does not have tonemaping or instance! No longer talking about Displacement (I hope soon in Kray), LWF, physical sky....

[jure]

Janusz has given you pretty elaborate answer already so I'm only going to write here very short one:

1. Like Janusz said uncheck "Cache Irradiance" on Kray general tab.
2. Add to Kray header of footer commands "recurse 3;" This is to mimick Fprime's "3" bounces setting.

However like Janusz pointed out - there is no point in trying to force Kray work as Fprime. Kray has completely other strenghts. Even if in this simple example may seem that Fprime performs better once you will start making complex interior scenes you will soon see why Kray is much much better and faster.

[jdomingo]

i believe kray is stronger in bigger scene and i have experience that and it never fails me. that is by using or with cache irradiance turned on. but unticking it or turning it off, it tremendously slow render with a lot of noice. i knwo how to set that up but i didnt use that on my big scene job because of render time and noise. so do you have tip or technique or good setup using uncache irradiance with same render speed with cache irradiance?

[Janusz Biela]

i believe kray is stronger in bigger scene and i have experience that and it never fails me. that is by using or with cache irradiance turned on. but unticking it or turning it off, it tremendously slow render with a lot of noice. i knwo how to set that up but i didnt use that on my big scene job because of render time and noise. so do you have tip or technique or good setup using uncache irradiance with same render speed with cache irradiance?

Does not exist ...QMC is QMC, must be slow (no interpolation). You can control QMC quality with min/max Rays in FINAL GATHER tab. For example 400/0 or 2000/0.

Btw if You saw very good renders (i mean perfect shadows and GI) in V-ray renders....this means many hours of render with QMC ...NO MIRACLES.
With QMC You can play on CPU i7 980 minimum......under this: only Photon mapping....

[jure]

Sometimes uncached render can actually be faster than Cached render. This can happen in scenes with lots of reflections and/or transparency.

[thomas]

Well, I for one LOVE Kray! We use fprime here as well, and it's good for product shots, but for interiors Kray beats fprime and Lightwave native every time. We also tried Vray once, but I hate how difficult it is to set up. Kray for the world!