Firecrest Pro ND 100x100mm Neutral Density Filter

I purchased the ND 16 stop filter Firecrest Pro filter and the Firecrest PRO Mk1 holder.
1)Quality filters are not cheap and the glass and colour balance of the filter reflect the expense. The glass is solid and feels like it will last a long time.
2) The construction of the filter holder is substantial and holds the ND filters in two slots with the option of a polarizing filter that has a screw thread that can be rotated with a thumbscrew on the side of the filter housing.
The polarizing filter screws into an adaptor that then attaches to the filter holder with a fixed tab and a sliding tab. The adaptor slots into fixed slot and the with the slider pulled away from the adaptor. When the slider is released the adaptor is locked in place. Both the clip and the slider are black so in low light situations its impossible to distinguish the clip and the slider. In addition the slider is fiddly to pull back with your thumb.
2) The holder comes with a light baffle that protects the holder from light leaks. This detail is a big plus as many filter system do not have this feature and you need to use gaffer tape to seal the leak. One issue with this solution is the clips that fit on the top and bottom of the unit, these two clips are thin and I wonder how robust they will be as they are very thin and clipping them into the light baffle and removing them takes careful handling.
3) I would recommend a test shoot before going out on an actual shoot because you need to attach the adaptor with the polarizing filter and rotate the polarizing for the correct setting, compose your image and focus.. This is where the procedure becomes tricky. You need to remove the holder or slot the ND filter into the holder, because the square filters are snug it is very easy to mess up your focus and composition. My process is to attach the polarizing filter to the filter adaptor (comes with three options, 82-77mm, 82-72mm, 82-67mm) then insert it into the filter holder. The polarizing filter is then attached to the lens and adjusted using the thumb screw. Once this is done you need to ensure the camera is set to manual and carefully remove the holder so that you don’t change the polarizer adjustment, composition or focus. Slide the filter into the filter holder and attach the light baffles. Then re-check your focus and composition before attaching the filter colder back onto the adaptor and camera.
It would have been good if the polarizer adjustor and adaptor were one unit and the filter holder then attached to this unit.

The construction and packaging for the filter and storage are excellent. The holder pouch has three pockets to separate the holder from the polarizer filter and filter adaptors, The filter pouch comes with a chamois lining and a padding.
Very good product that may need design tweaks. Possibly these cam with the M 2 version.