From the golden outer packaging comes a microfiber cloth wrapped in foil and the actual filter box. Inside is a filter that is oversized and heavy for the screw-in size. I have the filter in screw-in size 82mm and am testing it on the Leica Vario-Elmarit-SL 2.8/24-70 with the Leica SL2s.

The mount has a grooved grip ring for screwing in, which protrudes about 1 cm over the filter mount. This makes it easy to grip and screw in or out. There is no fiddling when changing the filter and no dealing with filter clamps when the filter is stuck! The manufacturing quality of the mount is excellent. The entire front frame of the filter has to be twisted to adjust the strength of the polarization. The screw-in knurled ring must be held in place because the rotation of the polarizing filter is difficult. The difficulty is not a design or manufacturing defect, but is for the 2nd function of the Filter is required, namely the darkening from factor 2 to 32, which is adjusted in the front part of the filter holder with 2 relatively large and easy-to-grip levers. If the polarizing filter adjustment were smoother, it would rotate with the ND adjustment.

The overhang of the filter holder makes a larger filter glass possible than with conventional screw-in filters, so that the thick filter does not vignette even at a 24mm focal length. The filter glass is visibly multi-layer coated; a water-repellent nano coating is applied to the front. The original lens cap can be snapped into the filter! All of this gives the impression of a very careful and well-considered design.

Polarizing and ND filters work as usual. There is no particular susceptibility to reflections and stray light. I cannot detect any impairment of the sharpness or an explicit color cast of the lenses. Of course, using the polarizing filter outdoors causes intentional color changes by filtering out the sky reflections, which means that, for example, green plants have a lower blue and a higher yellow component.

One basic problem with using the polarizing filter with mirrorless system cameras remains: except for reflections aimed at at an angle, the strength of the filter effect is practically undetectable on the OLED viewfinders. Landscape photographers who prefer polarizing filters are therefore recommended to use a DSLR with a mirror, in whose natural viewfinder image even small rotations of the polarizing filter are clearly visible. But this is not a fault of this filter, but rather affects polarizing filters in general.

Conclusion: A very carefully and practically constructed double filter at a very attractive price in comparison!

bought three adapters with a Canon R mount (one for Leica R, one for Contax and one for Minolta MD). They all reach exactly infinity. The internal anti-reflective paint is well finished. When I check them with a caliber, the two sides of the adapters appear planar (but I don't have any wide-aperture lenses to test that on). On the camera side, they are all precise and without light leakage. On the optical side, I noticed a slight light infiltration on two adapters. Of course, I purposely searched for them by bringing a 500 lux LED flashlight half a centimeter away from the adapter. Light penetration is very unlikely in normal situations (perhaps on an easel on the beach in August). I solved it anyway with a small rubber grommet. If you're shooting freehand, that's not necessary, the hand is hiding a possible infiltration. Overall they look like good adapters to me. Due to their robustness, they can withstand lenses up to 600/700 grams. However, I would not mount lenses that are larger than one kg on the nose.

By converting the M42 mount to a Leica M mount and using Techart's AF adapter, you can shoot autofocus with the Sony α7III. I can cover up the fact that it became difficult to concentrate because of Toshi. So I bought the M42 lens again because I left it on with the intention of remodeling it straight away. If you remove it, you won't understand.

To mount a Voighlander Leica M lens on a Fuji X E3, very good manual coupling card but a bit thick but that was on the announcement and it could be the optical pressure. So very satisfied.

bought an FD → Leica M. It's a FL lens, which may or may not be used depending on the lens, but I was able to use it normally with 50mmF1.4. The FD lens mount has a locking mechanism. Although the structure is more complicated than other mount adapters, the price is the same as other mounts, so it is very helpful. Thanks to this locking mechanism it is also possible to move the aperture flap and in the case of an F1.4 lens this is very convenient as it can be used as an aperture ring for F1.4 → F2.8 → F5.6 → F11 when the aperture is set to minimum.

Compared to the Leica 2000b

There is no problem with the "L/RL/M" Leica R-Mount Lens X Leica M Mount Body LM-EA7 confirmed with Summicron-R 50mm f2. Infinity is fine.

Leica M ring