Why are my TIFF images blurry?

on converting my RAW images from my dslr to TIFF, they take on an out of focus or 'soft' appearance which was not present on viewing the original raw file. i can sharpen them in GIMP and then save them as jpeg and they seem a little better, but I would rather the TIFFs would just come out good in the first place? what am i doing wrong?