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I have wondered how to use a 360 image in JPEG format (like you can grab here http://www.cgskies.com/ and have it render correctly and I just figured it out today. You have to correct the Gamma of the JPEG to .4545 and the image will rendering correctly in the BG. No more having to use an HDR format file for backgrounds.
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Matthew Valero, ASAI -
or You can just change the mode to sRGB instead of using the invert of the gamma.
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Ah! That works too!
Fernando, can explain the 3 options here and when to use them? Some of my materials have them set to linear and some are set to Gamma Corrected. I'm a little confused. By default, it seems the default is Gamma Corrected. When would you use linear?Matthew Valero, ASAIComment
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Hi Matt
Linear- the texture is already in the physical linear space and it doesn't need any correction. If you try to change the gamma, you will see that you can't do it.
Gamma corrected - the image is already gamma corrected and V-Ray need to remove the gamma correction for rendering. The default value is 1.0 in V-Ray for Rhino and Sketchup. This mean that we are going to use what ever the gamma of the images are (usaually gamma 2.2 for .jpg, .png, .bmp).
sRGB - the image data is in sRGB space and we need to convert it to Linear Space. So basically inverting the gamma. Usually the gamma for the images are 2.2, that is why if you use the Gamma corrected mode at .4545 or sRGB, you will get the same result.
Usually the gamma for .jpg, png are 2.2. HDRI have gamma 1 and we do not correct the gamma on the environment assuming that you want to use only .hdr or .exr. That is why if you use a .jpg in the environment, you will manually have to correct the gamma. So, the gamma you are typing is .4545 which is 1/2.2. The invert of gamma 2.2Comment
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Thanks for the explanation.Matthew Valero, ASAIComment
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