Filters - 2" or 36mm?

[Leti Theobald]

Hi, I've just decided to take my first step into mono astrophotography and wondering if the cost for a the 2" filters are worth or would I not notice any difference by getting the 36mm filters.

I will be using the ZWO filter wheel and ZWO 2600MM camera

I haven't bought anything yet so just trying to budget my expenses

Also, if anyone has recommendations of what brand filters to get that would be great - I was thinking Optolong but unsure if they are good enough

 

Edited June 26, 2023 by Leti Theobald
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[scotty38]

My view would be go 2" if you think you may go FF at some time. If not then 36mm should be just fine. I currently use 36mm on my 294m but I went 36mm just in case I bought a 2600 sized sensor.....

[teoria_del_big_bang]

I also was a bit worried when going to APS-C format and at the time already had 36mm filter wheel and filters and worried I would need 2". But so long as you do not place extra spacers in between camera and filter wheel (other than what is needed to connect them) you should be fine.

The cost to step up from 36mm to 2" is quite considerable, especially when buying good quality filters. Also ideally you will probably want a 7 position filter wheel (so you can have all the SHO and LRGB filters without changing) and this is also an extra cost and adds extra weight to the train.

So as said already unless you see yourself going to FF anytime soon then from my experience 36mm should be fine. 

Steve 

[Leti Theobald]

27 minutes ago, teoria_del_big_bang said:

I also was a bit worried when going to APS-C format and at the time already had 36mm filter wheel and filters and worried I would need 2". But so long as you do not place extra spacers in between camera and filter wheel (other than what is needed to connect them) you should be fine.

The cost to step up from 36mm to 2" is quite considerable, especially when buying good quality filters. Also ideally you will probably want a 7 position filter wheel (so you can have all the SHO and LRGB filters without changing) and this is also an extra cost and adds extra weight to the train.

So as said already unless you see yourself going to FF anytime soon then from my experience 36mm should be fine. 

Steve 

Thank you. Am I correct to say I need the 36mm unmounted filters? Also, any suggestions on Brand. I've always used Optolong on my current OSC camera but I know they are not the best of them.

[Leti Theobald]

58 minutes ago, scotty38 said:

My view would be go 2" if you think you may go FF at some time. If not then 36mm should be just fine. I currently use 36mm on my 294m but I went 36mm just in case I bought a 2600 sized sensor.....

Thank you. Am I correct to say I need the 36mm unmounted filters? Also, any suggestions on Brand. I've always used Optolong on my current OSC camera but I know they are not the best of them.

[teoria_del_big_bang]

1 minute ago, Leti Theobald said:

Thank you. Am I correct to say I need the 36mm unmounted filters? Also, any suggestions on Brand. I've always used Optolong on my current OSC camera but I know they are not the best of them.

Yes that's what I use anyway.

Brand, now there a question 🙂  I am by no means an expert and having only been into imaging for 5 years, give or take, do not have a great deal of experience with different filter brands. But you are wise to ask about and get some opinions on SGL.

All I can give you are my issues I have had and hope that helps.
Basically I always bought what I considered to be good quality (but not the most expensive) filters and stuck with Baader LRGB and SHO. And TBH they seemed to work fine for me except the OIII gave halos on the stars and bright stars were really bad. So eventually I sold the SHO, which were the Baader standard ones at the time, and replaced them with the Baader SHO ultra narrow band filters, hoping these would be better, but actually my OIII was worse and had terrible halos, and these were not particularly cheap. I emailed Baader several times but never had any replies. It may have been I had a one from a bad batch I do not know but got no help from Baader.

I now have a full set of Chroma filters and very happy with them (but my word they do not come cheap).
In hindsight maybe I should have stuck with the Baader RGB as they were fine and I see no difference with the Chroma, and could have saved a fair bit of cash. I think the Ha and SII chroma are better but again not a massive improvement but the OIII is on a different level altogether. I do have the advantage though that they are all the same thickness filters and so I can tune my back focus in well, if I had a mix of Baader at 2mm and Chroma at 3 mm then not sure how much difference that 1mm would make.

So I guess all I can say really is I would get the best you can afford, but perhaps you can save some cash certainly on the RGB, From other posts I have read the money needs to be spent of the NB filters, if you indeed intend to do some NB imaging, and OIII (again from what I read and experienced) seems to give the biggest issues. But also as I said if you intend to have all 7 filters in a filter wheel keeping at least the same thickness filters would be an advantage. 

There are so many other members and SGL with far more experience and knowledge than myself so do not rush into buying filters without getting more advice. I guess a lot depends on whether you intend to do NB as well as RGB.

Steve

[scotty38]

I went Antlia as a supposed middle ground option....

[Peds]

If you think you may go full-frame in the future, I'd get 50mm unmounted filters and skip 2" altogether.

If you're happy with sticking to APS-C, then 36mm unmounted is what you'll need.

Antlia is fantastic value for money and better than optolong, if you can stretch your budget a little bit. Whatever you decide, stick to the same filter width!

[teoria_del_big_bang]

4 hours ago, scotty38 said:

I went Antlia as a supposed middle ground option....

 

3 hours ago, Peds said:

If you think you may go full-frame in the future, I'd get 50mm unmounted filters and skip 2" altogether.

If you're happy with sticking to APS-C, then 36mm unmounted is what you'll need.

Antlia is fantastic value for money and better than optolong, if you can stretch your budget a little bit. Whatever you decide, stick to the same filter width!

I also read good things about Antila and a good deal cheaper than Chroma or Astrodon.

On another note whilst I have no experience with the filter drawer you intend to use I have read several threads about these being prone to light leaks and people using tape over the joins to eliminate the leaks, may be worth a search to see what people say about them.

Steve

[Leti Theobald]

oh no, I'll have a look

[teoria_del_big_bang]

12 minutes ago, Leti Theobald said:

oh no, I'll have a look

I don't thin it is a huge issue as people just seem to cover the  joins with some tape and it works fine, like I say just what I recall reading in past threads maybe this is fixed now on newer models I really cannot comment just to make you aware of possible issues.

Steve