Format for image submissions

I've started to get into macro photography, and I had thought about sending some pictures in to the site, I was wondering, though, what format you prefer? Size limitations?

I'm assuming this is a common spider of some sort (and I'm guessing you don't want a 10M image of it clogging up your inbox, so I'll just submit it here):



Please excuse the fact that the abdomen is out of focus - I'm still learning how to use a bellows, and the depth of field is always so shallow! Also, I was trying to hand-hold a flash, manually stop down the aperture and trigger the shutter at the same time, so it's a bit over-exposed.

It was somewhere between 3x-4x magnification, and since the sensor on my camera is 15.70mm tall, I'd guess that makes the body of this spider around... what, 3-4mm? It was on a shrub behind my apartment complex (in Austin, TX).

thanks, that's an argiope, I'll grab the image and put it on the argiope page!!