Topics

16

[Max] Resolved Bugs / Random seed can't be changed

« on: 2013-11-16, 10:21:37 »

Random Seed always remains at -2147483648 and can't be changed.

Noise pattern remains constant on animation. Bad - like looking through a dirty glass. Want to change to 0 to get animated noise.

17

[Max] Resolved Feature Requests / Support of file Lens Distortion parameters

« on: 2013-11-01, 10:08:45 »

Please add support for file Lens Distortions.



THE PURPOSE:
I have footage shot on 16mm (with lens distortions). Rendering background in Corona, but it doesn't match perfectly, cause no lens distortions.
Applying the distortions in post - matches great, but the pixels are smoothed and blurred by post. Need to render with lens distortions already there.

The lens distortions can be obtained for example by this utility:
http://help.chaosgroup.com/vray/help/300R1/tools_lens.htm

.VRLens format is plain simple:

version 0.2
# Calibration photo #0 begin
calibrationPhotoFile=C:\Users\vicnaum\Documents\lens-01d.jpg
focalLength=16.000
k0=1.0230671
k1=-0.0544355
k2=0.0103712
squeeze=0.9922962
lambda_x=-0.0099095
lambda_y=0.0023432
flags=1
# Calibration photo #0 end

(Couldn't find the second .lens file format specs.)

VrayPhysicalCam can load those .vrlens files and render using them (but only in vray, corona renders are still straight).
Btw, Corona supports Spherical vrayPhysicalCamera disctortions, but not File.

Also the parameters from Nuke lens distortion can be used (they look a bit different, but have Anamorphic mode also):

18

[Max] Resolved Feature Requests / Film-like tone-curves / tone-mapping

« on: 2013-09-04, 17:11:38 »

The idea is: Integrate film tone-mapping/ film-color to post-processing.

I guess now the corona has it's own internal tone-mapping / tone-curves to map real raw values to their screen presentation.

And it's also obvious that digital tone-curve is very different from film-one.
There are plenty of tables on the web with transformation from the real-world lightness data units to film density.
Of course one can apply some film-presets in photoshop/lightroom/etc, but doing it as a tone-map from raw render data should be much better.

Also you can implement some log format (google for "ARRI LOG C") - that can be used by cinema guys for better compositing.

Anyways, having some "Velvia" or "Fuji Superia" tone-mapping option in post-processing should look interesting (also the random sampler noise patterns can be similar to the corresponding film-grain :-).

19

[Max] Resolved Feature Requests / Neural network evolutionary settings optimization

« on: 2013-03-10, 21:25:40 »

Hello,

I was rendering one image, and it was doing more than 300 passes, but DOF noise still wasn't going off. I guessed - what if a renderer could see that there's DOF noise, and increase DOF samples to clean it?

So I had an idea - what if a renderer could optimize it's settings via evolutionary methods?

For example - it's rendering the passes...

On one pass it sets default settings.

On the other pass it varies the params slightly (samples, thresholds, etc). For example - sets one Light samples a bit higher.
Then it monitors - how fast is noise leaving.

If raising samples on this particular light helps to improve noise levels signficantly - it remains them a bit higher. If only the time increases, and the noise isn't much better - then it lowers the samples again.

And so on, and so on - on each pass it sets slightly different settings - and monitors the evolution of best settings for current scene.

I've seen some similar method here:
http://www.boxcar2d.com/

It uses evolutionary methods to develop the best passable car.

So, what do you think - is it practical to apply these methods to render?

20

[Max] Resolved Bugs / Checker map doesn't work on Bump

« on: 2013-03-06, 07:30:09 »

Simple 3dsmax Checker map, with two striped gradients in slots.

When I apply it to Diffuse, it looks okay:


But when I drag it into the Bump slot, then here's what happens:


On one checker - two gradients get mixed, and the other checker looks like it's empty.

Same happens to noise+gradient in checker slots, two bitmaps in checker slots, etc...



(Corona Alpha 3)