Originally Posted by Calzone
Thanks for the post and sharing. The MRC versions are worth the premium over regular B&W filters because one they are easier to clean, and for some reason they tend to stay cleaner.
I use filters all the time, but I compensate for the filter factor differently than you. I found that on my M6 and Nikon F3P that the TTL sensor does not respond fully with say a one stop offset for a yellow filter and only registers a half stop difference and with an orange filter only one full stop. When I use filters (mostly yellow and orange) I just set my film speed lower by one half stop to bring up the difference.
On film I would rather have the contrast on the negative so I can straight print in the darkroom. I assume the amount of post in digital becomes simpler with less tweaking when your Monochrome is used with filters?
The B+W MRC filters does indeed seem quite nice and very easy to clean compared to the Hoya branded filters that I previously owned (which was impossible to clean and which "locked on" to the lenses filter thread).
I tried compensating manually by using the filter factors but this resulted in quite over-exposed images on the MM atleast. Even with the red filter. I found that just letting the camera handle the metering worked best under the scenarios that I used them atleast. It might have been different under different lighting. I always checked the raw histogram to be sure though.
By using the filter factors (2, 4 and 8 respectively - 1, 2 and 3 stops) and compensating according to the filter factors the camera always over-exposed the shots. The maximum amount of manual compensation that I could perform was about 0.5 stop on the yellow filter, 1-1.3 on the orange and 2-2.3 on the red otherwise the images would be very over-exposed.