What filters do I need for OSC camera (e.g. ASI2600MC Pro)?

[AKB]

2 hours ago, ollypenrice said:

The image I posted mostly isn't mine, I just processed it.

Ah... the easy part of astrophotography.  😉

Edited November 13, 2020 by AKB

[rnobleeddy]

On 29/10/2020 at 19:49, ollypenrice said:

You'd be hobbling yourself trying to do Hubble Palette false colour with OSC.  The Ha would be captured using a quarter of the pixels, the OIII with half and the SII with a quarter. Given that mono imagers usually find the SII signal very feeble anyway, dividing it by four wouldn't be a good idea.

An OSC camera is best used as an OSC camera - that is a broadband natural colour camera. You can enhance Ha and OIII signal quite succesfully using filters but, at some point, you have to say, 'Why did I choose an OSC?'

Olly

I agree with your point if time and equipment/money weren't a consideration, but given that's not true for many people, I think these filters can be useful.

The dual band filters effectively separate the Ha and OIII signal completely. The Bayer matrix is there regardless of the filter, so if you're imaging a target that is rich is Ha and OIII anyway, it's a very effective way of increasing SNR. 

I don't have numeric data to prove it, but anecdotally, I got a significantly better image of the Veil using a dual band filter from Bortle 5 skies compared to no filter. 

Whether it's worth trying to add SII to create a SHO palette I don't know - but I tend to think of the dual band filter (with a little tweaking of the data) as being a fast way to produce a HOO image.

 

Going back to the original questions, at the very least, it seems sensible to use a CLS style filter with OSC cameras, although I don't know at what point they stop helping. Certainly helps SNR in Bortle 5.

[ollypenrice]

4 hours ago, rnobleeddy said:

I agree with your point if time and equipment/money weren't a consideration, but given that's not true for many people, I think these filters can be useful.

The dual band filters effectively separate the Ha and OIII signal completely. The Bayer matrix is there regardless of the filter, so if you're imaging a target that is rich is Ha and OIII anyway, it's a very effective way of increasing SNR. 

I don't have numeric data to prove it, but anecdotally, I got a significantly better image of the Veil using a dual band filter from Bortle 5 skies compared to no filter. 

Whether it's worth trying to add SII to create a SHO palette I don't know - but I tend to think of the dual band filter (with a little tweaking of the data) as being a fast way to produce a HOO image.

 

Going back to the original questions, at the very least, it seems sensible to use a CLS style filter with OSC cameras, although I don't know at what point they stop helping. Certainly helps SNR in Bortle 5.

I agree with that analysis, as I've said elsewhere.

Olly

[dhmiller]

15 hours ago, ollypenrice said:

Thanks very much for the post. Definitely what I was curious about.

 

However, I'm sure your camera will sing on the wintery Ha targets as well - Horse, Rosette, Cone etc etc.

Olly

 

 

[wimvb]

19 hours ago, ollypenrice said:

The image in Wim's link

T’wasn’t me, sir. Honestly. 😁

I do agree with your message to the OP. If your main interest is larger nebulae, a mono setup is the wiser choice. Osc + nb filters seems like trying to fit a square peg into a round hole. But a mono camera is incompatible with the Hyperstar configuration, because the camera is in front of the scope, and a filter wheel would block the view. I also question the whole hyperstar idea; the equivalent RASA (or even the smaller 8” RASA) is much easier because the optics is already aligned at the factory. I think  that other gentleman from my neck of the woods, ( @gorann) has proven that quite convincingly this autumn.

[ollypenrice]

19 minutes ago, wimvb said:

T’wasn’t me, sir. Honestly. 😁

I do agree with your message to the OP. If your main interest is larger nebulae, a mono setup is the wiser choice. Osc + nb filters seems like trying to fit a square peg into a round hole. But a mono camera is incompatible with the Hyperstar configuration, because the camera is in front of the scope, and a filter wheel would block the view. I also question the whole hyperstar idea; the equivalent RASA (or even the smaller 8” RASA) is much easier because the optics is already aligned at the factory. I think  that other gentleman from my neck of the woods, ( @gorann) has proven that quite convincingly this autumn.

Oops, sorry Wim! (Senior moment...)

🤣lly

[wimvb]

double post.

Edited November 14, 2020 by wimvb

[wimvb]

1 hour ago, ollypenrice said:

Oops, sorry Wim! (Senior moment...)

🤣lly

No worries. I’m becoming all too familiar with those moments myself, lately.

[wimvb]

22 hours ago, AKB said:

Ah... the easy part of astrophotography.  😉

That depends on how well you succeeded with the first part, is my experience. 😀

[aeneas]

7 hours ago, wimvb said:

I also question the whole hyperstar idea; the equivalent RASA (or even the smaller 8” RASA) is much easier because the optics is already aligned at the factory. I think  that other gentleman from my neck of the woods, ( @gorann) has proven that quite convincingly this autumn.

From purely AP perspective I would agree 100%; however in my case visual observing is quite important as well - great entertainment and educational experience for kids; seeing things with their own eyes for them is much much more special then looking at a heavily processed image on a computer screen. So I figure a C11 EDGE HD   with a Hyperstar   gives me kind of the best of both worlds - I can do either depending on the intent...

Amazing though what some people have been able to achieve with these newer OSC without any narrow band filters... but clearly that is not just the camera but also many years of experience!

[kirkster501]

The current generation of OSC cameras such as the ASI2600 or the QHY268C are astonishing in what they can achieve.