Filter Suggestion

Hi Jonathan

The 46 mm drawer I non-standard for astrophotography filters, so this is very limiting—you will be looking at filters meant for terrestrial photography. I assume that drawer could be removed?

ZWO has filter drawers that adapt for various lens configurations to attach to your camera, this way you could go with many options for standard 2” filters. The ZWO are based on standard camera backspacing, so I assume it would be fine with your lens if you can remove the drawer you have. This gives you many options now for filters, and the sky is the limit in the future if you enable standard astro filters.

If you want to shoot RGB images in Bortle 3-4, you can do quite well without a special filter. That is an option to start. There are light pollution filters to enable RGB with light pollution, but your skies are quite dark so the negatives of a filter may outweigh any positives.

For HO narrow band for nebula I would recommend something with a 3 nm bandpass. I personally use the 2” L-Ultimate, but there is a lot of choice from many vendors. Note I have tried wider band filters, but 3 nm is better. You can also get an SO filter, again there is a lot of choice from many companies at 2”. I use the Askar Colour Magic D2, but again, many options here.

I hope this helps

Rick

Hi Jonathan, Welcome to Astrophotography!

I was going to suggest you standardize your filter options to a 2” filter drawer (50mm). I did that with my ASI2600MC Pro camera. You can use larger filters for smaller sensored cameras, but not the other way around. And your 2600 has an APS-C sized sensor as you probably already know. By going with a 2” sized filter platform it can “future proof” your equipment in case you decide to go to a full frame sized sensor camera later on.

Like you, back in the beginning I tried to use my big telephoto lens on my DSLR and quickly decided I needed a dedicated telescope as a “lens”. And a dedicated Astro Camera, instead of wearing out my DSLR further by fooling with it doing astro imaging.

First, decide exactly what discipline you like. (E.G. I like DSO and nebula specifically) That can guide you towards what you are after. And what telescope(s) you’ll want to consider.

For my ASI2600MC and my location I find just a light pollution filter works fine. The camera captures everything I want in my images.

Edit in: For my imaging train, I mounted my 2” filter drawer directly onto my 2600 camera. So the filter is at its closest position to the sensor. I use an Antlia Quad LP filter. And most recently got an Svbony SV220 3nm Duo filter. The sv220, to me, has a tendency to be too red on some objects. But being it is in a filter drawer it is very easy to swap out. 😉

Hi again Jonathan

If you are building a system up I agree with Aloke, a filter wheel is a great option, compared to the drawer. I mentioned the drawer because they have them to mate to camera lenses. Even a manual wheel (though an electronic one is more flexible for the future) makes life so much easier and with a filter wheel I never have to open my system, filters stay clean and I can reuse my flats. Also with a drawer if you get multiple filters you need multiple holders to make it easy, quickly adds up in cost.

Rick

Jonathan Spool · Dec 16, 2025, 10:54 PM

Thanks guys. Lots to think about. Going with multiple filters makes me think that the PP would be a similar process to what I would need to do if I had gone with a mono sensor and rbg filters. Is going with a single 4 band filter a poor choice? Trying to keep the process simple and not get overwhelmed.

For your OSC camera, if you have a lot of light pollution, then a light pollution filter is good to have for RGB images. For narrow band you want an HO and an SO filter, so three filters maximum. If your LP is low you don’t need a filter for RGB. To do the same in mono you need separate R, G, B, L (or perhaps again a LP filter, could be the same one as for the OSC camera) Ha, OIII and SII filters. So you are talking 2 to 3 filters vs seven to do the same thing. Mono is also a step up, much more challenging. But you have an OSC camera, so getting seven filters and a mono camera, rather than 2 or 3 filters using the camera you have, is a hyge differential. For RGB imaging there is not a big difference in performance compared to mono, for NB you lose a bit on efficiency due to the extra filtering in an OSC camera. However, you do have many more switch-overs of filters, perhaps requiring refocusing each time, as well as many more flats with mono. So the difference in overall efficiency is probably not that big when you consider all the factors.

My own path has been to do OSC so far, including NB. I will switch to mono if I see a compelling reason to do it, which I have not reached yet after 5 years imaging.

But yes, some do eventually switch to mono and swear by it, just as some of us swear by OSC.

Rick