Convert sbig to pnm Online: sbig2pnm
You can use Tom's Editor to easily convert images from
SBIG CCDOPS .SBIG to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
SBIG CCDOPS is an image format with extension SBIG.
PNM images are uncompressed 24 bit RGB images. Can cannot store Alpha channel. PNM images come in 2 types: binary and text. Especially popular on Linux.