I have a large psb file which is an image of 39k by 27k pixels at 48 bpp. The image size is about 5.7 GB. PS CS6 trial only gives me the option to save it as a TIFF or Photoshop RAW only. I would like to use this large image as a master copy from which I can sample lesser quality images for printing. How can I save such images as a JPG or BMP file, that is downsample it and place the result in a smaller jpg or bmp file?
I read some other similar discussions and they all concern problems with the plugins folder. I have not inserted any plugins from previous CS versions. The only plugins that I have in there are authorized CS6 plugins for the scanner fix from Adobe.
Is it even possible to downsample from such a large image?
Yes, you could cretainly downsample it.
And remember that most file formats can't go beyond 30-32k pixels in either dimension, or 2 GB file size.