So.. all of my images that I shoot in darker environments/underexposed.. I get these vampire marks in my images... and other smaller marks that arent too visible until full res is seen... my lens looks clean...(might be the sensor) what's the problem?
That is dust on the sensor. There are cleaning kits for DSLR's depending on your Make and model, or you can bring it to most profesional photo studios or repair facilities and have it cleaned by them.
