Magnify Viewport with Redshift background
Hi, I am creating a 3D modification to a room using a photograph through the Background tab in a Redshift camera. I need more clarification to line up 3D objects to objects in the room. Is there a way to zoom into the viewport without moving the camera? To be able to increase the size of the viewport larger than 100%?
I tried using the Viewport> View> Film Magnify and Film Zoom but the background in the Redshift camera is not adjusted along with the scene.
Dr. Sassi last edited by Dr. Sassi
There is no native option right now, but I explored the typical suspects and have a few reports to write. Fingers crossed, RS will have the option at one point.
Please have a look at the scene below.
The easiest way to establish this would be by placing a Plane as a child of the camera.
Over two+ decades, the camera had 36mm for precisely that reason, as the " Frustum " width equals the "sensor". Sadly someone changed that, and so far, I could not get it back to the setting it had the functional 36 mm factory it had before. I have not given up, but the Preset options are in the upper right corner.
With that, the plane width equaled the Z distance to the camera. I typically placed a Plane set to Z- to the camera. Reset the PSR, and then type just its width into the P.Z
If you have your camera on 35mm (the "new" default) and setting it to 36mm would not matter, then it's easy. Otherwise, you need to do some math for any other field of view. (Or eyeball it.) I can help if you have some specifics. Even if the focal length changes, I can help, but I guess you won't do that with the Background image.
Either way, the plane should have the render aspect ratio.
After all that setup, you can switch the plane on and adjust for the time needed for the Field of view or the Camera> Object> Shift (previously known as Offset) camera parameter.
For the final render, you might switch the plane off.
Perhaps make a copy of the original camera to have a backup.
I hope that helps; if you have something that doesn't work with the idea above, please let me know, and I will search for something else.
All the best
Fantastic, thanks so much. Looks like it could work. I created an xpresso script to automatically adjust the size of the plane based on the distance from the camera. I just need to recreate in my scene. I am using a 21mm focal length so I will need to make some adjustements.
One additional question: If I am making moves with the Film Zoom and Move, is there a command to get a back to my original zoom level, my original view from the camera?
I just hacked through the math, I think good enough to get it to work in my scene. Thank you again - great solution and Xpresso makes it so much easier.
Still just curious about the Film Move and Zoom tool - gettting back to original view. After looking at the docs - looks like the Film Zoom is automatically adjusting the focal length and field of view. I could get back to the original view returning my focal length back to 21mm. However, if I use the Film Move tool, I don't see a corresponding value to change to get back to the original view as with the Film Zoom.
Dr. Sassi last edited by
Great that you got XPresso working. I'm always happy to help, but I know the feeling of setting things up and knowing what is happening.
For now, I would leave the Filmtools alone when in Redshift. I have filed a report yesterday, so fingers crossed that this is working soon.
My tip would be to use the Focal length and the Shift parameters so that you can reset those.
When you work with a 21mm, I assume, going by the provided image; you know already to handle distortions with the image. As I write in a forum, I like to mention those things as a general tip. If I knew which practical lens you have used, I could explore what kind of distortion it had, if there is a test anywhere. Sometimes these lenses have barrel and cushion distortion mixed with a "Mustage" distortion, which needs extra care.
There is a lens distortion workflow in Cinema 4D, and you get great results with enough care (i.e., enough lines in image five and more).
All the best