Correct image aspect ratio in Redshift material
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I'm using an image for a Redshift material and don't know how to ensure it has its correct aspect ratio. I've tried all the Projection methods in the material's tag, but all seem to distort it and I have to eyeball the correct aspect ratio. Is there a way to make sure it's exactly what it should be?
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Hi kariomart,
This question would mean you work on a flat object, as a sphere would always distort the image.
The use of 2D textures on a 3D object is (as you surely know) via UV(W).
The UV space is measured in 0-1, meaning it is normalized, to allow swapping out low-res to high-res images, for example.The UV polygons are the translator of how an image is used on an object.
However, things change in animation, and stretching is a typical way of making geometry changes possible.
I nearly hear you, that is not what I mean, I have a plane and want a picture on it. perhaps in 16:9 ratio. Same story, once the UV is set up, it should work just fine.
You can always set a reference with a plane that follows the pixel dimensions (given you have square pixels, or adjust for non-square pixel use, like in the old SD formats).
Side by side, this should help.Is it a plane and a specific ratio? Or? Then I can share an example.
Cheers
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Hi Dr. Sassi,
As always, thanks for the help. Here is a link to the project, along with a screenshot of where I am with the UV:
https://drive.google.com/drive/folders/1vuAQqqt32VyG0za-3vSCA1NrOdxk_vuV?usp=sharingPlease ignore the projection method I have on the object. That was my initial attempt at eyeballing correct proportions. I understand that once I UV unwrap it, it should be set to UVW Mapping.
How can I get the polys in the UV editor to have the same proportions as what I see in the Viewfinder?
Thanks,
kariomart -
Hi kariomart,
The same size wouldn't be an option, as the UV space is normalized to the image. In short, if an image is 1024 x 2048 and the UV setup is that all are covered by it, then the UV space stays in 0-1 normalization but adapts to the image. Which subjectively appears to be a normalization to 2:1, as it is a translation from 2D information towards a 3D object. (Deformers can change the size while not affecting the UV.)
The simples way is to calculate the point where it stops, and cut there, make a selection, and fill the whole UV 0-1 space with the UV, so the selection provides a clear framing. Not simple to explain or suggest that for general use, but here is an example:
https://projectfiles.maxon.net/Cineversity_Forum_Support/2025_PROJECTS_DRS/20250921_CV4_2026_drs_25_TXrc_01.c4d.zipI am sure some would like to point to Texels. Here I'm not sure if that would work as you need it.
https://help.maxon.net/c4d/2025/en-us/Default.htm#html/Texel_Density.html?Highlight=TexelWhat I have done in the example file below:
The height was easy to explore
Then I selected the partial circle (Edge to Spline). With a quick XPresso set up measured the length.This allowed me to calculate the needed Pixel for the horizontal Length. X = 670x401/203
Since the label would cover the polygons completely, that was the fastest way for me.
Relax the outer UV Polygons and use the Command "Fit UV to Canvas."Now the new texture (401x1324) wraps around the full outside, while keeping the Label intact.
I colorized the extra space, but that can be just empty.Example
https://projectfiles.maxon.net/Cineversity_Forum_Support/2025_PROJECTS_DRS/20250921_CV4_2026_drs_25_TXuv_01.zipEnjoy your Sunday
