I would like to do a star trail shot as demonstrated here (http://www.exposureguide.com/night-sky-photography-tips.htm) but the maximum shutter speed is 30 seconds. Is there any way to remotely hold opn the shutter for a longer period of time from my computer so i don't have to hold the shutter button myself?
Read more: How to hold open the shutter on a nikon D3100 from a mac?