Star Trail Light Leaks with Nikon D600

One of my favourite subjects for photography is star trails. On a recent trip to Martha Creek near Revelstoke, I was disappointed with some of the results I was achieving with my Nikon D600, especially given that the exposures were 8 minutes in length:

Minor Light Leak at Martha Creek

I had much better success with my Nikon D90 in earlier shots:

Milky Way At Lac Le Jeune

Initially I thought this was being caused by the fire or small lights in my campsite. I made adjustments, and faithfully re-composed to a different location and attempted a 30 minute exposure. The results were very disappointing to say the least:

Major Light Leak at Martha Creek

I began to question the usefulness of a D600 in one of my favourite styles of photography, and was considering calling Nikon support to report the issue. But before doing so, I did a quick search on Google and observed results that were similar. 

After digging further on various forums, I concluded that I might have had light leaking through the viewfinder of the D600 , which was odd considering I had not had this problem with the Nikon D90 . I did some quick experiments using my Cokin IR and Cokin ND filters during daylight conditions:

Cokin IR Filter - Light Leaks

Cokin ND8, ND6, & ND4 Filters Stacked - Light Leaks

Light Leaks! After adding the Nikon DK-5  to the viewfinder of the Nikon D600  (you know, that small piece of plastic that your camera came with, but you didn't know to do with!), I was pleased with the results:

Cokin IR Filter - No Light Leaks

Cokin ND8, ND6, & ND4 - No Light Leaks

I have not yet tested this in a star trail scenario, but I am quite confident about what I was observing, and relieved that my decision to move to a D600 was not a bad one.

Cheers!