| Re: Best for image sizes. I'm not sure there is a suitable format for you. If you want to reduce the size this means to throw information out of the files but you want to keep the current quality and size also, so this will be a problem.
The JPEG format itself is already a compression with losing of information (quality) but to some acceptable extent.
Maybe you should make a compromise between the size of the file and quality+size of the images. |