Need some digital long exposure help.?

Question: Need some digital long exposure help!.!?

Much of my work is long exposure shooting with very limited ambient light!. What I get out of my D200 after a ten minute exposure at ISO 400 and f/5!.6 is a reverse vignette (a purplish paleness emanating from different points around the image) and an amount of noise that nearly renders the image unusable!. Does anyone have any experience!? Should I just shoot a proof with my DSLR and then reshoot it in 35mm to have a film neg!? Any input would help a lot!Www@QuestionHome@Com

Best Answer - Chosen by Asker:

if its ten minutes shoot it at 100 ISO!. What lenses are you using as well!? 18-200!? For long exposures that lens is crap!. It produces heat for long exposures destroying images, mostly over 10 seconds, but if you're doing 10 minutes thats probably whats causing it!.Www@QuestionHome@Com

Yeah that's normal on a Nikon!. It's just the Processor!. Just try and change the colours in PSWww@QuestionHome@Com