|
If you don't need it to be secured (yes I read that it's desired but understood it to be not a necessity), I have the Hercules Optica flat panel. It's not fancy but it's decently priced and it's manual. They go from USD $70 -> USD$150 ex shipping.
Note though with these (and I guess with other astro flat panels), one could have quite a long duration for 3nm NB filters (in my case up to 40 sec per sub through an Sii filter, 25 sec with Ha, and 6.5sec with Oiii with my F10 scope).
I assume it'll be the same with other flatfield panels.
|