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Looking to upgrade to mono and would like some advice

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#1 Jmurphy18

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Posted 23 May 2024 - 10:55 AM

Folks, I am planning to upgrade from my present configuration of OSC ZWO 2600MC.  Everything I have read and resources points me in the mono direction.   Right now my budget is limited so I am wanting to purchase some items a piece or two at a time to limit the sting of filters, fliter-wheel and camera all at once.  I have the 2600MC pro and a filter drawer.    My present system is ZWO ASI so I will most likely stay there with the wheel and camera.  I am thinking to get filters 1st then the filter wheel following finally by the camera.   I would like to get the 2600mm if my budget will allow.  Can you offer a recommendation on filters, size and which wheel.   I had the thought LRGB for filters vs Ha, Oil, S.  I have a while to go as I have to convince the boss on this expense.  FYI I am shooting a 405mm refractor



#2 hyiger

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Posted 23 May 2024 - 11:08 AM

I have the 2600MC pro. The ideal filter sizes are 36mm unmounted. Are you planning to keep the 2600MC? If so, use it for broadband imaging. So for the MM if you are budget constrained start with getting a 7x36mm EFW filter wheel and the L, Ha and O-III (you can add S-II later). Make sure they are from the same manufacturer and are parfocal. My advice on the narrow band filters is don't cheap out on them. It makes a difference. 

 

I see you are NN, Virginia. I'm a part time resident of Williamsburg. I would guess you are in a Bortle 7? I'd probably go with 3nm filters which will be a bit more expensive than 5nm but are worth it. I have the Antlia Pros which I really like. You can sometimes find them in the classifieds here on Cloudy Nights. I picked up second-hand the full set of filters LRGBSHO with the wheel and camera together for $2800 (which was a bargain). 


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#3 drmikevt

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Posted 23 May 2024 - 11:09 AM

Stick with ZWO for the filter wheel - get the 7 position 1.25" wheel, not the 5 position wheel which you will outgrow.

 

As implied above, you can stick to 1.25" filters for the 2600MM

 

With filters, more or less, quality is consistent with price.  But, for LRGB filters, you do not need to get the priciest.  A lot of people go with Optolong, which are fine.  Chroma is the top end and Antlia seems to be the current middle ground go-to.  Get whatever your budget will allow.  



#4 fastfiveoh

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Posted 23 May 2024 - 11:36 AM

For my 2600mm I went with the ZWO EFW II 7 position for 36mm unmounted filters.  I went with the middle ground on filters and got the Antlia LRBG pro, and a 3nm Ha.



#5 Skysmacker

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Posted 23 May 2024 - 11:57 AM

I would think you would want to stick to a MINIMUM of 36mm filters if using the 2600MM.

 

Based on what i've read, using the 1.25" filters there will be a serious loss of signal towards the edges which would ultimately waste a lot of the FOV you paid for with the APS-C sensor.

(If this isn't the case, then I guess I might go shopping for a 2600MM to use with my filters, lol!)

 

Here's a very informative discussion regarding this very thing...

 

https://www.cloudyni...nd-125-filters/


Edited by Skysmacker, 23 May 2024 - 11:59 AM.

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#6 idclimber

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Posted 23 May 2024 - 12:11 PM

I have had the 2600mm since it was released, replacing the 1600mm I had prior. 

 

You will need 36mm filters with the 2600mm. I can recommend the ZWO 7 slot filter wheel as it is designed to attach to the camera with screws instead of the M48 thread. This also gets the filters a bit closer to the sensor which is desirable. 

 

You do not need 2" filters unless you have a scope capable of full frame. These are typically larger scopes and more expensive. 

 

Brands of filters should be directed by budget. I believe the ZWO is near the least expensive. The Chromas the most. You pretty much will get what you pay for but even the ZWO filters work pretty darn good. These easy to upgrade if your budget in the future allows. Most here go for mid level brands like Antila or Optilong. 

 

The other thing you have to decide is bandwidth. Narrower bandpass like 3nm are more expensive than wider. I have 8nm and wish I had ordered the 3nm. I do not think it makes a huge difference, especially if you are not in a high light pollution area. I am Bortel 2-3 so it was less important for my needs. Get what you can afford, as you can easily sell them if they are in good condition. 

 

You will not need the 2600mc once you move to the 2600mm. I am not certain if that is factored into your budget. I am considering the OSC version myself only because I now have a second mount and plan to image with both. 


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#7 hyiger

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Posted 23 May 2024 - 12:36 PM

You will not need the 2600mc once you move to the 2600mm. I am not certain if that is factored into your budget. I am considering the OSC version myself only because I now have a second mount and plan to image with both. 

I kept my 2600MC for galaxies or to collect RGB to add my narrow band stacks using the 2600MM.  

 

To the OP, definitely go for the 36mm filters. 

 

To add to what @idclimber is saying, I definitely like the whole ZWO setup with EFW and OAG-L. The whole thing bolts together as one unit which makes it easy to swap in and out with different scopes

 

IMG_2231.jpeg


#8 DeepSky Di

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Posted 23 May 2024 - 06:28 PM

Doing what was outlined in the original post is spending money and getting no immediate benefit. Even when the mono camera eventually shows up, it's not going to be transformative with just LRGB filters - just a different way of doing what's already possible with the OSC.

 

On the other hand, doing SHO is definitely new, different and exciting but it can already be done with an OSC with an Ha-Oiii filter and an Sii-Oiii filter in a filter wheel. Check out Optolong L-Ultimate, Askar Color Magic D1 and D2. These filters are typically 2" so will need a 5x2" filter wheel. Don't plan on switching a filter wheel between cameras - it gets bolted onto the camera and once that's done it's best to leave it there.


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#9 sn2006gy

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Posted 23 May 2024 - 07:13 PM

I agree with Deepsky Di, don’t buy mono of 2600 just to do LRGB. You won’t gain much over OSC for such a huge cost. (3-4 grand with camera, wheel and filters) - if you plan to do a lot of narrowband or you are in great bortle 1-2 skies then i’d make the investment.
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#10 archiebald

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Posted 23 May 2024 - 08:34 PM

Doing what was outlined in the original post is spending money and getting no immediate benefit. Even when the mono camera eventually shows up, it's not going to be transformative with just LRGB filters - just a different way of doing what's already possible with the OSC.

 

A couple of points to the OP

 

1.) As mentioned by several, an IMX571 sensor cannot be used with anything less than 36mm filters unless you want severe vignetting.  If you are price constrained to 1.25" / 31mm filters, then you are locked into something in the range of IMX533 or IMX294 camera.

 

2.) I have been been looking into going mono one day, and based on what I understand, DeepSky Di's comment quoted above is slightly off or confusing (based on what I have received as advice and feedback).  Every owner of a mono camera will tell you how superior the possible image quality is over an equivalent OSC, even if only shooting through LRGB filters due to better efficiency and no bayer filter to shoot through, so there is a definite benefit to be had even without having the Narrow Band filters.


Edited by archiebald, 23 May 2024 - 08:35 PM.

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#11 DeepSky Di

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Posted 23 May 2024 - 11:22 PM

A couple of points to the OP

 

1.) As mentioned by several, an IMX571 sensor cannot be used with anything less than 36mm filters unless you want severe vignetting.  If you are price constrained to 1.25" / 31mm filters, then you are locked into something in the range of IMX533 or IMX294 camera.

 

2.) I have been been looking into going mono one day, and based on what I understand, DeepSky Di's comment quoted above is slightly off or confusing (based on what I have received as advice and feedback).  Every owner of a mono camera will tell you how superior the possible image quality is over an equivalent OSC, even if only shooting through LRGB filters due to better efficiency and no bayer filter to shoot through, so there is a definite benefit to be had even without having the Narrow Band filters.

Absolutely, and we discuss this incessantly on these forums.

 

However, it all depends on what the OP wants to achieve with resources that are limited. Do mono because everyone says it's better? Take essentially the same images with some improvement in quality and/or speed? Or go ahead and forge new ground with SHO?

 

I began the mono journey using an OSC with L-eXtreme. I then added a mono camera and LRGBSHO filters and another OAG. After that I added the Askar Color Magic Sii-Oiii to my OSC filter wheel. When I do get a clear night, I take out both cameras and work on different targets.

 

Depending on the goal or interest, it may be better to get a couple of duo bands now and get started with the OSC, rather than purchasing a filter wheel and filters long before the camera that enables them to be used. I always wanted to do SHO and was ready to take the leap around the time the Askar Color Magic Sii-Oiii arrived. I did get the mono rig first, but adding the Sii-Oiii to my existing OSC rig was comparatively inexpensive.


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#12 bobzeq25

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Posted 24 May 2024 - 02:30 AM

The CRUCIAL question is what are the targets? 

 

Narrowband (for mono cameras) and duoband (for OSC cameras) filters simply don't work on broadband targets like galaxies.  They are just not an option, because they reduce broadband light WAY too much.

 

Given the same total imaging time, LRGB provides _significantly_ better signal to noise ratio than OSC on broadband targets like galaxies (where narrowband and duoband filters don't work).  The reason is that the L filter puts all the light on all the pixels all the time.  Experienced imagers are not spending the bucks to do LRGB for no reason.  It's not life changing, but it is significant.  Moreso in light polluted skies.

 

But the number of galaxies (and galaxy groups) you can image with a 405mm focal length scope is small.  Complicated business, this.  <smile>

 

As many have pointed out 1.25 filters are way too small for an APS-c chip.


Edited by bobzeq25, 24 May 2024 - 02:38 AM.

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#13 sn2006gy

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Posted 24 May 2024 - 07:50 AM

yeah at 405mm, just stick with your 2600mc pro. dither every frame, do bayer drizzle (cfa) and maybe add more time. save yourself a lot of money.

i never experienced any significant difference unless i was trying to limit my total integration time. The bulk of the hassle had been image editing but there are tried and true workflows and tools that make osc feel much closer to lrgb if you like that workflow and flexibility:

#14 idclimber

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Posted 24 May 2024 - 09:42 AM

I know I am going out on a limb here, but I gather that the OP is not considering LRGB filters to get better broadband images, but as an incremental budget constrained move to SHO/HSO imaging. 

 

Although the margin of difference between OSC and LRGB is small and arguably not worth the great expense to anyone on a budget, narrowband OSC filters (dual, tri or quad) do not take the same images as SHO filters with a mono camera. 


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#15 hyiger

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Posted 24 May 2024 - 10:22 AM

Although the margin of difference between OSC and LRGB is small and arguably not worth the great expense to anyone on a budget, narrowband OSC filters (dual, tri or quad) do not take the same images as SHO filters with a mono camera. 

This.

 

I really can't stand the narrow band images I take with my 2600MC and dual narrow-band filter anymore now that I've moved to mono (2600MM). They look noisy and muddy in comparison. Broadband on the other hand I prefer to use my OSC camera. For large galaxies like M33 I also use the mono camera to take H-alpha to mix in with the RGB from the OSC camera. 


Edited by hyiger, 24 May 2024 - 10:22 AM.

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#16 unimatrix0

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Posted 24 May 2024 - 10:37 AM

I say save enough money for the 2600mm.

 

I have the 533mm pro, but honestly it's best used for small nebulae or galaxies.

Anything small, anything you don't mind getting only a partial piece of it.

 

For that, it's fantastic. 

 

The problem is, that most nebulae during the "milky way season" are quite large.  Even guys with the redcat at low focal length of 250mm, they end up with an APS-C camera to trying to fit in the narrowband DSO's. 

 

At higher focal lengths, like 400-600 where most refractors and fast Newtonians are, your view is even more limited and the APS-C is sorely needed, unless you want to crop inside a nebula with a smaller camera.  

 

Another maybe unpopular opinion, I don't do mosaics with a mono camera and 3 filters. It's just too much hassle.

If I would do a mosaic, I would use an OSC camera and I have done that a couple of times.  It's too much mess, when I did mono mosaic, I wanted a paycheck after I was done. The best/easiest way to image with a mono camera is 1 frame set of the DSO and 3 filters deployed (S2, OII, Ha) and go from there.  

 

So again, save your money for the 2600mm and 36mm filter wheel (7 position)  with  LRGB-SHO filters. Get the filters from the same brand/maker, saves yourself another headache about filter offsets and the refocusing hassle if they aren't parfocal. 

Just my 2 cents. 


Edited by unimatrix0, 24 May 2024 - 10:41 AM.


#17 Jmurphy18

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Posted 24 May 2024 - 10:55 AM

I have the 2600MC pro. The ideal filter sizes are 36mm unmounted. Are you planning to keep the 2600MC? If so, use it for broadband imaging. So for the MM if you are budget constrained start with getting a 7x36mm EFW filter wheel and the L, Ha and O-III (you can add S-II later). Make sure they are from the same manufacturer and are parfocal. My advice on the narrow band filters is don't cheap out on them. It makes a difference. 

 

I see you are NN, Virginia. I'm a part time resident of Williamsburg. I would guess you are in a Bortle 7? I'd probably go with 3nm filters which will be a bit more expensive than 5nm but are worth it. I have the Antlia Pros which I really like. You can sometimes find them in the classifieds here on Cloudy Nights. I picked up second-hand the full set of filters LRGBSHO with the wheel and camera together for $2800 (which was a bargain). 

Thanks, yes I do plan on keeping the 2600MC.  My long range goals is to get a longer ~ 1000mm refractor and have on camera on each scope and shoot with both.  Thank you on the size.  I had originally considered 2” just because I had the 2” L-enhance filter.  I have this in my filter tray.  I like the 7x36 on the wheel.

 

Yes in NN.  I located near Eustis and NN Park so I am closer to Bortle 6 here.   I have a retention pond in the back yard and that is where I shoot smile.gif  Cool on Williamsburg I have lots of cycling miles in that area when I was younger.  Thanks on the filters.  I already did a search.


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#18 Jmurphy18

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Posted 24 May 2024 - 11:12 AM

Drmikevt:  thank you

fastfiveoh:  thank you

skysmacker:  thank you and also for the link!

idclimber - Dave:  Thanks much.  36mm and a 7 slot on the filter wheel.  Now.  I understand on the filters.  I have been down that road with my camera’s.  long time photographer.  You get what you pay for in filters.  I have some height end and some medium.  No bottom end.  Pitched them in the 80’s.  


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#19 Reidkon

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Posted 24 May 2024 - 11:40 AM

Doing what was outlined in the original post is spending money and getting no immediate benefit. Even when the mono camera eventually shows up, it's not going to be transformative with just LRGB filters - just a different way of doing what's already possible with the OSC.

 

On the other hand, doing SHO is definitely new, different and exciting but it can already be done with an OSC with an Ha-Oiii filter and an Sii-Oiii filter in a filter wheel. Check out Optolong L-Ultimate, Askar Color Magic D1 and D2. These filters are typically 2" so will need a 5x2" filter wheel. Don't plan on switching a filter wheel between cameras - it gets bolted onto the camera and once that's done it's best to leave it there.

I started another thread regarding filters for an ASI2600MM Pro before I saw this thread and thinking rather than spending a bunch for a new camera, maybe I will keep my old ASI294MC Pro and buy narrowband filters.  Would you recommend getting the Optolong L-Ultimate or the Askar Color Magic filters?   I already have a 2" filter wheel so I am thinking the Askar filters are the way to go.



#20 Jmurphy18

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Posted 24 May 2024 - 11:54 AM

Doing what was outlined in the original post is spending money and getting no immediate benefit. Even when the mono camera eventually shows up, it's not going to be transformative with just LRGB filters - just a different way of doing what's already possible with the OSC.

 

On the other hand, doing SHO is definitely new, different and exciting but it can already be done with an OSC with an Ha-Oiii filter and an Sii-Oiii filter in a filter wheel. Check out Optolong L-Ultimate, Askar Color Magic D1 and D2. These filters are typically 2" so will need a 5x2" filter wheel. Don't plan on switching a filter wheel between cameras - it gets bolted onto the camera and once that's done it's best to leave it there.

Thanks much!  I will look into this.. I had read about the Askar filters earlier this year but they have been out of stock for a while now.  I have the L-enhance filter (12nm) vs the 3nm you mentioned   You have given me something to think on here.   Thank you.!

 

sn2006gy:  Thanks    FYI I am in Bortle 6 not 2-3 so very polluted 



#21 hyiger

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Posted 24 May 2024 - 11:57 AM

Thanks, yes I do plan on keeping the 2600MC.  My long range goals is to get a longer ~ 1000mm refractor and have on camera on each scope and shoot with both.  Thank you on the size.  I had originally considered 2” just because I had the 2” L-enhance filter.  I have this in my filter tray.  I like the 7x36 on the wheel.

 

Yes in NN.  I located near Eustis and NN Park so I am closer to Bortle 6 here.   I have a retention pond in the back yard and that is where I shoot smile.gif  Cool on Williamsburg I have lots of cycling miles in that area when I was younger.  Thanks on the filters.  I already did a search.

Of course 2" filters will work perfectly fine. They are just overkill and expensive for that camera. Only reason to go with 2" is if you are planning to upgrade to a full frame camera some day. If you do that you will also need a scope that supports full-frame as well. And... full-frame is SUPER expensive. 

 

You'll be happy with the 7x36mm EFW. If you don't already have one, you will need a pier extension for your mount. The filter wheel will get in the way and will need to be rotated out of the way so you don't slam into the mount before a meridian flip. 

 

For "medium" focal lengths, I really like my AT130EDT which gives me 910mm at f/7 and 728mm at f/5.6

 

I'll be in Williamsburg during July and most of August. Hopefully the weather holds up. 


Edited by hyiger, 24 May 2024 - 11:58 AM.


#22 Jmurphy18

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Posted 24 May 2024 - 12:15 PM

Archiebald: thanks.  I am definite with the aps-c sensor.  I have that now and do not want to downsize.  I shoot full frame on my main camera’s now 51/62mp so I know that value of MP size.

 

Deepsky DI:  I have moved beyond shoot just 1 hr of data and I have been collecting 12-15 hrs.  I thought to add different items beside straight color.

 

bibzeq:  I was shooting nebula’s in the winter but now with only galaxie’s my only option right now that is what I am doing.  I just started in Nov so just bouncing around and the weather is not helping much :)

 

Sn2006gy:  thanks.  

 

Unimatrixo:  Thanks that was my original plan



#23 Jmurphy18

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Posted 24 May 2024 - 12:50 PM

Of course 2" filters will work perfectly fine. They are just overkill and expensive for that camera. Only reason to go with 2" is if you are planning to upgrade to a full frame camera some day. If you do that you will also need a scope that supports full-frame as well. And... full-frame is SUPER expensive. 

 

You'll be happy with the 7x36mm EFW. If you don't already have one, you will need a pier extension for your mount. The filter wheel will get in the way and will need to be rotated out of the way so you don't slam into the mount before a meridian flip. 

 

For "medium" focal lengths, I really like my AT130EDT which gives me 910mm at f/7 and 728mm at f/5.6

 

I'll be in Williamsburg during July and most of August. Hopefully the weather holds up. 

For the MM I will go with the 36mm. The Full frames are like buying my A7r4a shocked.gif   More MP thank I need right now.  I wondered about the pier extension on the AM5

Thanks on the AT130EDT.  I have been looking at this as a future purchase.

Cool on Boeing in Williamsburg.  Coming during the “cool” season I see LOL.  Maybe we can meetup and swap storied   HAGD



#24 hyiger

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Posted 24 May 2024 - 12:59 PM

For the MM I will go with the 36mm. The Full frames are like buying my A7r4a shocked.gif   More MP thank I need right now.  I wondered about the pier extension on the AM5

Thanks on the AT130EDT.  I have been looking at this as a future purchase.

Cool on Boeing in Williamsburg.  Coming during the “cool” season I see LOL.  Maybe we can meetup and swap storied   HAGD

Which tripod are you using? Is it the TC40 that comes with the AM5? With your current scope I strongly recommend getting the ZWO PE160. You will definitely need it once the filter wheel is attached. Otherwise when you slew toward zenith, you are going to have trouble clearing the tripod legs. Even with the pier you need to (in some cases) rotate the EFW 90 degrees to get it out of the way. When you get a heavier, longer scope you'll need the PE200 and (in my opinion) a sturdier tripod. This is my setup for the AT130EDT: PE200 with Celestron Heavy Duty tripod. 

 

IMG_2004.jpeg

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#25 DeepSky Di

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Posted 24 May 2024 - 01:08 PM

I started another thread regarding filters for an ASI2600MM Pro before I saw this thread and thinking rather than spending a bunch for a new camera, maybe I will keep my old ASI294MC Pro and buy narrowband filters.  Would you recommend getting the Optolong L-Ultimate or the Askar Color Magic filters?   I already have a 2" filter wheel so I am thinking the Askar filters are the way to go.

I have the Optolong L-eXtreme and the Askar D2 Sii-Oiii. As far as I know these are only available in 2" size. 

 

The L-eXtreme is good but puts halos on bright stars. I don't get any halos with the D2.

I don't have experience with the L-Ultimate or the Askar D1, but there are YouTube comparisons. I also see that Askar are bringing out a more expensive G range with narrower band passes. I have not seen any reviews of these yet.

 

Another option is instead of and Sii-Oiii filter, get Sii-Hb duoband. Hb has a blue wavelength similar to Oiii. There are some pros and cons to this.

- One argument is that the Hb is usually in the same part of space as Ha so gives no new information. Since Ha is abundant and Oiii is often a struggle, might as well get all the Oiii you can.

- The other argument is that there are occasional targets where the Hb is distinct from the Ha and therefore capturing it can give more structure to the image. Of course, you only have 3 colors (red, green and blue) to map to, so having 4 wavebands to combine means getting creative. I saw an image where Hb had been mapped to white. 

 

There are tri-band and quad-band filters that pass all these wavelengths but combine the result in a way that can't be split during processing. All you can do is separate red from green / blue. If you have Oiii and Hb in the same image, or Ha and Siii in the same image, they can't be split using channnel separation.

 

Regarding filter sizes, these seem to be only available in 2" size. I already had a 5x2" filter wheel for my APS-C OSC camera (071MC). For my 2600MM I use 36mm unmounted in a 7x36mm EFW.




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