This is my first attempt at using resizing in RawTherapee. The results baffle me. The jpeg I’m starting with is 3.4 MB. I have set resizing on the full image, using Lanczos, with scale set to 0.50. I expect the resultant rescaled size to be 1.7MB (50% of size) or 0.85MB (50% of both width and height) depending on how I interpret what the scale setting means. I get neither result; with repeated tries I get results varying between 156KB and 1.3MB with no differences in processing requirements between attempts. It can only be a ‘user error’, but I can’t see where.Any suggestions?
In most, if not all editors, scaling is done to the image size in pixels, not to the file size in bytes. Therefore the file size is not directly proportional to image size.
When we use words like “size” here, it’s best to prefix them with a qualifier when there could be misunderstanding.
Thanks; got it. When I examine pixels dimensions, before and after resize, they are exactly as you advised. Now I know where the ‘user error’ is…
1 Like
Usually the same place mine are! 
1 Like