<p>Yes it is possible to mount astrophotography filters with 48 mm threads to DSLR or mirrorless cameras using step-up or step-down adapter rings to mate with the lens threads.</p>
<p>I have occasionally attached broadband UHC type filters on DSLR lenses for wide field imaging. However, I have not tried dual band filters such as the one you linked, but have read some discussions of their use, probably in the cloudy nights forums under the DSLR/Mirrorless camera topic.</p>

CC BY-SA 4.0
2023-05-06T00:40:25.297Z
2023-05-06T00:40:25.297Z
amateurAstro
<p>I'm considering using a <a href="https://optcorp.com/products/optolong-l-extreme-dual-band-filter-2-inch" rel="nofollow noreferrer">2&quot; filter</a> for astrophotography with DSLR and mirrorless cameras. Filters are typically measured in mm, but I understand that a &quot;2 inch&quot; filter is really a 48mm filter.</p>
<p>Does this mean that 2&quot; astro filters can be used with cameras with a typical 48mm step-up/down ring?</p>

CC BY-SA 4.0
2023-05-25T04:50:25.240Z
It’s the first time I hear/read that 2″ filters are really 48 mm in diameter. I’d like to know your sources for that, as I doubt it. But what I’m really commenting for, is that if what you are trying to install is *smaller* than the hole/thread, then a very affordable solution could be adding tape—normal scotch tape can work for some, or black electric tape for other purposes. I once bought a 0.965″ filter only to discover my eyepieces were really 1″, but adding tape fixed my problem without having to buy any adapter.
Pierre Paquette
<amateur-observing><photography>
How to mount a 2" filter to a DSLR or mirrorless camera?
Ana
# How to mount a 2" filter to a DSLR or mirrorless camera?

(Asked by: username_0 on 2023-05-05)

I'm considering using a [2" filter](https://optcorp.com/products/optolong-l-extreme-dual-band-filter-2-inch) for astrophotography with DSLR and mirrorless cameras. Filters are typically measured in mm, but I understand that a "2 inch" filter is really a 48mm filter.

Does this mean that 2" astro filters can be used with cameras with a typical 48mm step-up/down ring?

**Tags:** amateur-observing, photography
> **Comments:**
> **username_1**: It’s the first time I hear/read that 2″ filters are really 48 mm in diameter. I’d like to know your sources for that, as I doubt it. But what I’m really commenting for, is that if what you are trying to install is *smaller* than the hole/thread, then a very affordable solution could be adding tape—normal scotch tape can work for some, or black electric tape for other purposes. I once bought a 0.965″ filter only to discover my eyepieces were really 1″, but adding tape fixed my problem without having to buy any adapter.  

---

## 1 answers

### Answer by username_2 on 2023-05-06. Score: 1

Yes it is possible to mount astrophotography filters with 48 mm threads to DSLR or mirrorless cameras using step-up or step-down adapter rings to mate with the lens threads.

I have occasionally attached broadband UHC type filters on DSLR lenses for wide field imaging. However, I have not tried dual band filters such as the one you linked, but have read some discussions of their use, probably in the cloudy nights forums under the DSLR/Mirrorless camera topic.


---

