Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Feature Requests => Topic started by: jms.lwly on 2019-03-28, 17:08:21

Title: Grad Filter
Post by: jms.lwly on 2019-03-28, 17:08:21
Probably a long shot, but thought it worth suggesting. When taking photos in real life, I use a grad filter to create dynamic skies (or occasionally foregrounds) - particularly for architectural exteriors or landscapes.

I often recreate this in Corona with a simple plane with gradient map in front of the camera - but this can become frustrating with multiple cameras, and moving things around in a scene. I've linked the grad filter plane to the camera which helps, but still not ideal. With the Corona Camera ideally mimicking real life, could this be something that is integrated into the camera - similar to the Bokeh control (e.g. Value of effect, controllable by a map, etc)?

It can obviously be done in post, but it's simply not the same and doesn't give the same realism.
Title: Re: Grad Filter
Post by: burnin on 2019-03-28, 23:06:30
maybe a thought to consider for an advanced vignette :)
Title: Re: Grad Filter
Post by: romullus on 2019-03-28, 23:37:19
Save two or more renders with different exposure and blend them with gradient in photoshop. Or even better, save render to linear format and play with exposure to your heart's content.
Title: Re: Grad Filter
Post by: Frood on 2019-03-29, 08:40:36
I often recreate this in Corona with a simple plane with gradient map in front of the camera - but this can become frustrating with multiple cameras, and moving things around in a scene.

I know it may get already getting boring myself praising this workflow, but if you would just animate one cam with that linked plane to create your different shots on different frames it would be easy :) You could even animate the gradient map/opacity for each shot for angle specific adjustments.


Good Luck




Title: Re: Grad Filter
Post by: Philip kelly on 2019-03-29, 09:57:32
Off topic :
Can I say I had a look at your website, the Holly Cottage renders are excellent.
Lovely Images.

Philip
Title: Re: Grad Filter
Post by: jms.lwly on 2019-03-29, 16:00:30
Save two or more renders with different exposure and blend them with gradient in photoshop. Or even better, save render to linear format and play with exposure to your heart's content.

 - To be fair, this method hadn't occurred to me... I usually render to CXR and process in Corona Image Editor standalone (due to unusual Windows/Mac workflow) - so will certainly give this a go and see if it gives the desired real-life quality.

I know it may get already getting boring myself praising this workflow, but if you would just animate one cam with that linked plane to create your different shots on different frames it would be easy :) You could even animate the gradient map/opacity for each shot for angle specific adjustments.

 - Nice thought, however the issue with multiple cameras here isn't actually animation related - it's having multiple cameras in one scene for different stills, and when I have grad filters attached to each camera they appear in the other views too as a floating graduated square... for the time being I just have to remember to turn on the appropriate filter for the camera and the others off.

maybe a thought to consider for an advanced vignette :)

 - This is exactly the sort of thing I was pitching for... something for my wish list!

Off topic :
Can I say I had a look at your website, the Holly Cottage renders are excellent.
Lovely Images.

 - Thanks Philip! All of the exteriors on that project utilise a grad filter as above... (there are a few more to come actually... I'll pop them on the Gallery page once the others are sorted).
Title: Re: Grad Filter
Post by: TomG on 2019-03-29, 16:52:09
"it's having multiple cameras in one scene for different stills,"

I think that was the suggestion - connect the plane and camera, and don't have multiple cameras, simply animate that camera / plane group so that frame 1 is camera position 1, frame 2 is camera postition 2. Then you don't have multiple cameras, just one camera moving to different places (rather like a photographer moving from place to place to take the different shots).

EDIT and then rather than choose the camera to render from, you simply choose the frame. Also makes it easy to render all of the shots at once, just render it as an animation.
Title: Re: Grad Filter
Post by: Frood on 2019-03-29, 17:00:34
it's having multiple cameras in one scene for different stills, and when I have grad filters attached to each camera they appear in the other views too as a floating graduated square...

Yes, exactly Tom. Kick all cams except one and animate that (only) one through frames to create your stills. But leave frames in between for the ability to do motion blur stuff.

If you would like to keep multiple cams: remember there is a simple to use "Object visibility" list for CoronaCameras where you could exclude all your planes/squares.


Good Luck



Edit: Deleted optimization workflow, does not really saves work :)

Title: Re: Grad Filter
Post by: jms.lwly on 2019-03-29, 20:33:21
Yes, exactly Tom. Kick all cams except one and animate that (only) one through frames to create your stills. But leave frames in between for the ability to do motion blur stuff.

If you would like to keep multiple cams: remember there is a simple to use "Object visibility" list for CoronaCameras where you could exclude all your planes/squares.

 - Thanks both - I had used this method (one camera, many positions) previously and found it to be a big of a time thief, but maybe I should revisit because of the filters...

Excluding from camera visibility is definitely useful - but maybe one day it could just be a button in the VFB... wishful thinking!