What is the Baader UFC AUX D 36mm Filter-Holder used for?
This is a spare or additional holder for a single 36mm unmounted filter. It is designed to be used with the Baader UFC-RD50 Filter Slider (#2459113). Its purpose is to allow you to have multiple filters pre-mounted and ready for quick swaps in the field.
Does this Baader UFC AUX D 36mm holder come with the UFC-RD50 slider?
No. This product is only the auxiliary filter holder itself. You must purchase the Baader UFC-RD50 Filter Slider separately to use it within the UFC system.
How many 36mm filters can I mount in one Baader UFC AUX holder?
Each Baader UFC AUX D 36mm holder is designed to hold exactly one 36mm unmounted filter. To use multiple filters, you will need to purchase one holder for each filter you wish to have ready.
Can I use the Baader UFC D 36mm holder to image the Horsehead Nebula (Barnard 33) with different narrowband filters?
Yes, this is an ideal use case. You can purchase several of these holders to mount your H-alpha, S-II, and O-III 36mm filters. This allows you to quickly swap between them using the UFC-RD50 slider, minimizing downtime while capturing data for a color composite image.
Will this Baader UFC AUX holder work with my 8" f/4 Newtonian and the UFC system?
Yes, as long as you have the complete Baader UFC system configured for your telescope's backfocus, this holder will work. Its function is dependent on the UFC-RD50 slider, not the telescope type. The UFC system itself is designed to be adaptable to nearly any telescope, including f/4 Newtonians.
Why would I buy this Baader UFC AUX holder instead of just using the one that came with my slider?
The key benefit is efficiency. Owning multiple holders allows you to create a library of pre-mounted filters. Instead of stopping your imaging session to unscrew and swap a filter in the dark, you can simply pull out the entire slider/holder assembly and insert the next one in seconds.