Another way to prove this 50mb minimum rule is stupid: you can take an image from a D100 or D70, save it as a 32-bit TIFF file, and there you have it, a 70mb file that's only 3000x2000 (6mp). Aboslutely no added information, just takes more space :glare:
I think you'll find that they won't accept 32-bit files. 16bit files must be circa 5300x3500mb to meet submission guidelines = 50mb.
now, not to drag us back into a tangent, but quck comments:
The logic behind the 50mb requirement, as I understand it, is as a quality control guideline. Think about it from a photo buyers and agents perspective. If you were an agency attempting to get images from photographers and needed a fast way to move a tremendous volume of images through quality control, a strict set of guidelines would be the best way.
It might just be a size (file size) requirement, and it is counterintuitive, but frankly setting such a guideline is the best way to regulate quality. If all images are about 50mb 300dpi (just a standard) 16bit, you can open up any image, view it at 100%, and know pretty much immediately whether it is of high enough quality. That is a bar that the industry sets. And frankly, an image might look great at native output, but how will it hold up when you blow it up to xxx size? The buyer needs to know what he or she is getting and won't tolerate images of varying sizes. Remember, it's all about standards. A standard has to be somewhere, whether for editing, or output. 50mb is simply a representation of a quality standard in a method easily translated to both buyers and photographers.
Finally, regarding some of the prior comments, in my experience most agency personell are better versed in digital media than most of the photographers they represent. As a photographer, I appreciate this and what the agent does: sell my images.