Starlight Xpress Mini filter wheel Advice

[johngm]

Hi Everyone,

First, you are all welcome to blame me for the turn in the weather, because i have taken delivery from FLO of  a Starlight Xpress  trius Pro 694 mono camera + SX Mini filter with integrated OAG. Along with these, i purchased a 1.25" Baader LRGB CCD filter set . Now the problem is, when i screw in the filters, the knurled part of the Baader filter clashes with the Prism of the OAG. (Image 1). The only way i could get around this, was to screw the filters in from underneath ( camera side image 2). The operation of the filter wheel is fine in this configuration, but, aren't  these Baader Filters non reflective on the camera/thread side ? although, i must admit, i couldn't see any difference with my eyes. If they are inverted, the only way around i can see is unscrewing the collars that hold the glass in place and flipping them, but i worry i might scratch them. Any ideas ? especially would be interesting to here from other SX owners..

Anyway, these are the images i have taken of the issue.

[SyedT]

8 minutes ago, johngm said:

Hi Everyone,

First, you are all welcome to blame me for the turn in the weather, because i have taken delivery from FLO of  a Starlight Xpress  trius Pro 694 mono camera + SX Mini filter with integrated OAG. Along with these, i purchased a 1.25" Baader LRGB CCD filter set . Now the problem is, when i screw in the filters, the knurled part of the Baader filter clashes with the Prism of the OAG. (Image 1). The only way i could get around this, was to screw the filters in from underneath ( camera side image 2). The operation of the filter wheel is fine in this configuration, but, aren't  these Baader Filters non reflective on the camera/thread side ? although, i must admit, i couldn't see any difference with my eyes. If they are inverted, the only way around i can see is unscrewing the collars that hold the glass in place and flipping them, but i worry i might scratch them. Any ideas ? especially would be interesting to here from other SX owners..

Anyway, these are the images i have taken of the issue.

This was an interesting read: https://www.baader-planetarium.com/en/blog/unmounted-filters-which-side-should-face-the-telescope/

Confirms that the non-reflective side should be towards the camera, and that the way they design the mounted filters would mean that putting them as you have in the first image is the only correct orientation. The only permanent solution not requiring experimentation with various ideas that I can think of would be to switch to unmounted filters as they sit right inside the carousel with a small portion jutting out.

[johngm]

8 minutes ago, SyedT said:

This was an interesting read: https://www.baader-planetarium.com/en/blog/unmounted-filters-which-side-should-face-the-telescope/

Confirms that the non-reflective side should be towards the camera, and that the way they design the mounted filters would mean that putting them as you have in the first image is the only correct orientation. The only permanent solution not requiring experimentation with various ideas that I can think of would be to switch to unmounted filters as they sit right inside the carousel with a small portion jutting out.

Agreed regarding the filters, but this SX filter wheel doesn't appear to accommodate unmounted filters. There is no recess to sit the filter on, or screw holes to hold the filters in place.

John

Edited June 3, 2020 by johngm
Typo

[SyedT]

6 minutes ago, johngm said:

Agreed regarding the filters, but this SX filter wheel doesn't appear to accommodate unmounted filters. There is no recess to sit the filter on, or screw hole to hold the filters in place.

John

You'd have to purchase a 5x36mm carousel for the filter: https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-5x-36mm-unmounted-filter-carousel-for-mini-filterwheel.html.

Since you've bought these items new, you could contact FLO and ask for an exchange for a 5x36 mm FW (https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-usb-mini-filter-wheel-5-x-36mm-with-oag.html) and 36 mm filters?

The other thing I'm thinking of is the number of filters you have. If you're hoping to do narrowband work in the future, then it'll be a pain to open up the FW and exchange the LRGB filters for narrowband filters and you'll expose them to dust as well. If so, getting a full-size FW would be better as it can accommodate 7x36mm filters: https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-usb-filter-wheel.html The OAG is extra and so the whole setup is £169 more, but depends on what your preferences are.

Edited June 3, 2020 by SyedT

[johngm]

10 minutes ago, SyedT said:

You'd have to purchase a 5x36mm carousel for the filter: https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-5x-36mm-unmounted-filter-carousel-for-mini-filterwheel.html.

Since you've bought these items new, you could contact FLO and ask for an exchange for a 5x36 mm FW (https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-usb-mini-filter-wheel-5-x-36mm-with-oag.html) and 36 mm filters?

The other thing I'm thinking of is the number of filters you have. If you're hoping to do narrowband work in the future, then it'll be a pain to open up the FW and exchange the LRGB filters for narrowband filters and you'll expose them to dust as well. If so, getting a full-size FW would be better as it can accommodate 7x36mm filters: https://www.firstlightoptics.com/starlight-xpress-accessories/starlight-xpress-usb-filter-wheel.html The OAG is extra and so the whole setup is £169 more, but depends on what your preferences are.

Just looking on the FLO site now, and that might be an option to think about. I don't know if i could stretch to the extra £250 for the Midi wheel, however, at £39 a pop, could buy 2 X 5 pos 36mm wheels and have one for NB and one for BB. Just keep the one i'm not using in a sealed air tight zip bag. I have to ask though, surly this is a poor design if it cant except 1.25" screw filters the correct way around, and that is what it is marketed as

John

[SyedT]

1 minute ago, johngm said:

Just looking on the FLO site now, and that might be an option to think about. I don't know if i could stretch to the extra £250 for the Midi wheel, however, at £39 a pop, could buy 2 X 5 pos 36mm wheels and have one for NB and one for BB. Just keep the one i'm not using in a sealed air tight zip bag. I have to ask though, surly this is a poor design if it cant except 1.25" screw filters the correct way around, and that is what it is marketed as

John

If you buy the 7x36 and guide head then that's £449. Buying the 5x36 mini FW + an extra carousel would be £319, so you'd effectively be paying £130 more. In terms of design, I think the issue arises with the filter mounts themselves; I'm not sure if Astronomik make thinner filter mounts for example. I've been using 7x36 for a while now so can't remember.

[johngm]

I also meant to say SYed, i wanted the integrated OAG, because i will be using it with my RC8 scope. I tested it today with my ED80 and ASI290mm mini on a distant aerial , at its prety much parfocal. Makes life so much easier.

John

[SyedT]

9 minutes ago, johngm said:

I also meant to say SYed, i wanted the integrated OAG, because i will be using it with my RC8 scope. I tested it today with my ED80 and ASI290mm mini on a distant aerial , at its prety much parfocal. Makes life so much easier.

John

I see! In that case, getting the 5x36 mm FW and an extra 36 mm FW is the best way to go for your particular setup.

Edited June 3, 2020 by SyedT

[johngm]

1 minute ago, SyedT said:

I see! In that case, getting the 5x36 mm FW and an extra 36 mm FW is the best way to go for your particular setup. 

But thats a spot on Idea of yours though regarding the 36mm filters. I'll message FLO tomorrow and see if they'll exchange the filters (obviously me paying the difference) and order a couple of carousels. They do have them in Stock.. Thanks again for the suggestion pal, cracking idea 👍

John

[Adam J]

I have never really gotten the appeal of these 5 position wheels.

I would actually go so fars as to say I find them annoying as in some cases you are litterally talking about the same electronics with a minor firmware change yet they are massively cheaper. Or looking at it the other way, whats to justify the price hike for a bigger wheel beyond a tiny bit of extra machining.

I cant imagine ever wanting anything less than a 8-position wheel for 31mm / 1.25 inch filters at anyrate but at the same time resent the price difference.

Adam

 

Edited June 3, 2020 by Adam J

[SyedT]

5 minutes ago, johngm said:

But thats a spot on Idea of yours though regarding the 36mm filters. I'll message FLO tomorrow and see if they'll exchange the filters (obviously me paying the difference) and order a couple of carousels. They do have them in Stock.. Thanks again for the suggestion pal, cracking idea 👍

John

No problem! It's up to you, but to save £39 you could return the 5x1.25 FW, order a 5x36 FW and an extra carousel. The 5x36 FW is shipped in 4-6 days though, so depends on how impatient you are (I'd probably be impatient enough to get the 2 carousels if I'm honest!). In terms of the larger filter wheel, I've had experience of using two 5x2" carousels, and I found it annoying to have to exchange them whenever I needed to change from BB/NB, especially if it was in the middle of an imaging session in the winter!

Edited June 3, 2020 by SyedT

[johngm]

29 minutes ago, SyedT said:

No problem! It's up to you, but to save £39 you could return the 5x1.25 FW, order a 5x36 FW and an extra carousel. The 5x36 FW is shipped in 4-6 days though, so depends on how impatient you are (I'd probably be impatient enough to get the 2 carousels if I'm honest!). In terms of the larger filter wheel, I've had experience of using two 5x2" carousels, and I found it annoying to have to exchange them whenever I needed to change from BB/NB, especially if it was in the middle of an imaging session in the winter!

I just spotted that, same price to. I'll message FLO tomorrow. Don't mind waiting, looks like iv'e put a Jinx on the weather with my new toy 😔 lol

[johngm]

51 minutes ago, Adam J said:

I have never really gotten the appeal of these 5 position wheels.

I would actually go so fars as to say I find them annoying as in some cases you are litterally talking about the same electronics with a minor firmware change yet they are massively cheaper. Or looking at it the other way, whats to justify the price hike for a bigger wheel beyond a tiny bit of extra machining.

I cant imagine ever wanting anything less than a 8-position wheel for 31mm / 1.25 inch filters at anyrate but at the same time resent the price difference.

Adam

 

Totally Agree mate, that sums up pretty much anything we buy. Unfortunately from my perspective, i cant afford the 7/8 position FW with Parfocal OAG. The price difference will almost buy me a set of NB filters.

John