I've been trying to a good contrast for my DNA bands, however I haven't been so successful. I've been running the ladders only to make sure I get a good contrast before further experimentation. I created the gel using 70mL 1X TAE buffer, 0.84g of agarose (so about 1.2% gel), and 28ul EtBr. I set the electrophoresis box at 90V for about 1 hour hoping to get a better gel but the results came out looking the same as if I had ran it at 110V. I've attached a picture of my gel. It was taken with a DSLR, no flash, 20 seconds exposure time. Any tips would help. Thanks
I normally use 1-2 ul (depending on whether my gut tells me I have a lot of DNA, or a little that day) in a 70 ml 1% gel (which is probably 60-65 ml after boiling in the microwave). I have no trouble whatsoever seeing ladders and DNA samples of down to 100 ug in wells not much bigger than about 4 mm.
Here are the factors that you can manipulate to alter the brightness:
I can see that you have a ladder in the middle, so at least some DNA is definitely there.
Also, keep in mind that off-the-shelf cameras are not good at imaging the EtBr fluorescence, because the wavelength is a bit unusual. The nice pictures you see in papers are taken with a specialized geldoc machine or a camera with an appropriate filter.