B+W Filter 091 Dark Red 77 mm MRC Schott RG 630. Compared to the lighter 090 red filter, this one even darkens the reds near the yellow tones in the spectrum, as its transparency only begins in the orange-red region. It produces dramatic effects and extreme tonal separation for graphic effects. That accounts for the large filter factor of appr. 8.
Multi-Resistant Coating (MRC)
MRC by B+W is not only an extraordinarily effective multiple layer coating, it is also harder than glass, so that it protects filters from scratches (for instance when cleaning the filters), and it is also water and dirt repellent, thus facilitating filter maintenance.
F-Pro filter Ring
The F-Pro filter Ring, 5mm, is made of brass and provided with a matte black paint that minimizes reflections. F-Pro can be used on most lenses down to 24mm, size 24x36.
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