Clearglass Filter 31mm (for focusing/dust protection)

Our Clear glass Filter (C) for focusing / dust protection is the correct type of filter with the full visual band pass, that you are looking for. Our new Baader luminance filter (CMOS-optimzed) is already with an included UV/IR-Cut band pass manufactured. Please be advised that only our 50.4 mm / 50x50 mm and 65x65 mm filters have a thickness of 3 mm, all types of smaller filters are 2 mm in thickness.

The only filter which lets UV through is U-Venus-Filter (350nm) in 2": #2458291 or 1.25": #2458292 If it isn't suitable for your needs, we unfortunately do not have anything else.

You can find the filter thickness of each and every filter and every size on the product page. Click on the filter size, scroll down, click on "Specifications" tab

Currently some products are out of stock due to COVID delays in manufacturing and supply chains. Unfortunately, we cannot predict delivery times and have many thousands of customers, which we cannot inform individually when a product is available. Therefore we have developed two automatic tools which we would like to ask you to use. 1st Newsletter: If you enter your email address here, you will receive a monthly newsletter with a lot of information about our products and new releases https://www.baader-planetarium.com/en/newsletter/ 2nd "Notification Tool" On the page of items that are currently not available, there is a field "Notify me when the product is available". If you enter your email address there you will be informed as soon as the product is in stock. Thanks for your understanding!

Yes, the filter is dielectrically coated and planeoptically polished. Please note that also the edges are coated to prevent ageing of the filter - these filters are coated once they are finished and not cut from a coated piece of glass. You can read more about the manufacturing process here: https://www.baader-planetarium.com/en/blog/information-about-baader-filters-and-filtercells/

You can see the transmission curve of the filter if you select the desired filter size. Then, the curve will appear as one of the product images.