Baader Single Polarizing Filter

Transmission of a polarizer is varying depending on the rotational position in the lightpath as well due to added polarizing effects of the imaging optics itself. We do not have info on transmission values sorry to say. Traditionally the glass-embedded polarising plastic-film inside any such filter will only transmit sufficiently in the range from 400 to 700 nm. We have no information within our field of amateur astronomy about poarisers covering the UV – nor UV and VIS together. Concluding we think that using our (nor other common) polarizers for your intended purpose would not at all yield satisfying results.

Yes, sure, this is possible and a good idea. Or you can mount the second filter in the eyepiece, then you can simply rotate the eyepiece for stepless brightness adjustment for example for Moon observations

Yes, sure, this works!

Both Hyperion and Morpheus eyepieces feature a 1.25" thread, so it is the easiest if you simply use a Baader Single Polarizing Filter 1¼" #2408343 for the eyepieces and a 2" for the star diagonal. If you already own two single 2" polarizing filters, you can place one in the reducing adapter from 2" two 1.25" - most of them provide a 2" filter thread, or you can use one of ours: https://www.baader-planetarium.com/en/accessories/adapters-imaging-accessories/eyepiece-clamps.html?filter_threads_eyepiecesided=516&filter_threads_lenssided=523 If you insert a 2" filter into the body of a Hyperion, it will act like a finetuning ring with the length of the filter height (6 or 8mm, depending on the filter cell) and increase the focal length of the eyepiece. These rings and their effects are described e.g. in this PDF: https://www.baader-planetarium.com/en/downloads/dl/file/id/134/product/1210/hyperion_eyepieces_application_examples.pdf

A single polarized filter is only polarizing the light in one direction. It can be used to dim light which is already polarized, like in a Herschel Wedge. Double polarizing filters are two single polarized filters in a row. When you turn one of them, you see that the light gets dimmed stageless from very bright to very dark. Double polarizing filters are mainly interesting for visual Moon observation. For high end / high resolution photographic use we recommend grey filters (ND filters)