FIRECREST FILTER HOLDER LIGHT LEAKAGE TEST
Last few weeks I had the opportunity (thanks to Formatt Hitech) to test the Firecrest 100×100 filter holder on light leakage when shooting long exposures. According to Formatt Hitech the revolutionary top and bottom covers almost completely eliminate light leakage when shooting long exposures. Herewith a short evaluation of my tests.
Light leakage could occur when shooting (long exposure) photographs. Unwanted light that enters in due to different causes like the viewfinder, sides on the camera, tilt-shift lens or filter system (stacked filters). Light is much like water, if there is a gap it will find it’s way in somehow. For more information about light leakage in general, Joel Tjintjelaar wrote a post on his website www.bwvision.com
Tested the holder with(out) end caps and outer case, one Firecrest 100×100 16 stops ND filter, multiple angels, exposure times between four and seven minutes under various weather conditions.
When shooting without end caps and outer case (maximum sun and bright sky) there were traces of light visible caused by a small gap between the filter and the built in low-profile gasket ring. Also adjusting (tightening) the filter slots did not solve the issue completely in this case. The gasket ring should be completely covered by the filter to prevent any leakage with this barrier. Of course the holder is not intended for use without outer case and solid or vented end caps. Shooting without was to find out how the different barriers perform. Another copy of the holder did not have any traces of light visible because there was not a gap at all between the filter and the gasket. Probably there was an issue with the initial tested holder. As it was the holder used for the test, I want to mention the leakage issue.
When using the interchangeable end caps (solid) and outer case there were no traces of light visible at all. However, when taking a close look, there are very small gaps due to the interchangeable end caps option. Despite of this there were no light traces visible with the two barriers of light protection. As the holder is designed to use with various filters and end caps the holder cannot completely eliminate light leakage.
In general, to completely eliminate light leakage there has to be no gaps at all between the filter(s) and the lens. When using an additional filter like a 150×100 grad, there even will be more to count with because of the leakage and reflections that could occur between filters. Using a gasket between the filters could create an extra barrier. Cover up (places where light can gets in) completely is the only way to achieve the best results.
Formatt Hitech developed (with the outer case and end caps) a filter holder that almost completely eliminates light leakage. They researched what their customers wanted and I think they did a good job! For more information visit their website www.formatt-hitech.com.