Preventing Light Leaks
Light leaks are a common occurrence in long exposure photography and come from a variety of places. The long exposure times the Firecrest 13 and 16 stop filters allow have shown light leaks coming from the body of the camera while other light leaks come from light passing between stacked filters. A few common ways to prevent this from happening are:
- Place a hat over the top of your viewfinder
- Use gaffers tape to cover the viewfinder and any ports or doors on the camera body
- Gently cover or wrap the lens with a dark scarf, cloth or lens bag with the end cut out (Joel uses this trick)
- Cover the top of the filter holder with a cloth or gaffers tape to prevent light passing between stacked filters
- Use the foam gasket supplied with ProStop and Firecrest filters
- Use the light covers supplied with the Firecrest 100mm MKII Holder Kit
It’s best to keep the ND filter closest to the lens. This is to minimize reflections and light leaking behind the ND which will cause significant deterioration of the image.
If the filter has a gasket, place the gasket rearward toward the lens to create a light tight seal between the filter and the holder.
Experiment with using the gasket in and out, especially when using ND filters that include a light gasket.
Attaching or Removing a Gasket
85mm and 100mm Firecrest ND filters come with a foam gasket. This can be attached to the filter to help prevent light leaks and provides a tighter fit in the holder. Attaching the gasket is simple. Lay the filter down on a soft cloth, peel the paper off of the gasket, place in desired spot and press down.
If you decide to no longer use the gasket first gently peel off the foam. Any remaining residue can be soaked off in warm water with a mild soap.
The gasket isnt require when using the light covers supplied with the Firecrest 100mm MKII Holder Kit
Setting White Balance and Focus with NDs
Every camera responds differently to using ND filters. When using a lot of ND, you might get best results from setting focus and white balance with the holder off. Then add the holder right before making the exposure. However, if the live view on your camera is capable of looking through moderate strength NDs, it is preferable to adjust focus and white balance with the filters on the camera in a ready-to-shoot configuration. This lessens the chance of bumping the lens and disturbing your focus or altering your framing.