Lets say my Keyword is "German Shepherd Pictures" and I am going to have 200 pictures of german shepherds. What do I name my images, and what do I put for the alts? If I named each image germanshepherd1.jpg, germanshepherd2.jpg, germanshepherd3.jpg, and the alts accordingly would google pick this up as spam?
I'd suggest that you should not name all images as same. It will be a good idea is you use names like german-shepherd.jpg, black-german-shepherd.jpg etc.
I agree with rosiee, I don't have that much experience with image file names, but if these are considered when evaluating keyword density by the SE, then having 200 images with the exact same keywords would definitly be spamy in their eyes. Plus, using diverse other keywords, you can try to SEO for other keyworkds or phrases relative to the site.
alt name help a bit...but google use content to guess what the photo is..i have photo rank for keyword that is no in alt
see top searched keywords, divide pictures into 3-4 blocks and then name each with 1 keyword , But now top keyword named images will be there , u must try to name diff, if german1.jpg is top image in google then u name as german01.jpg.