Any ideas how to remove a ND3.0 filter from a Baader wedge ? It seems stuck or glued?

[Cliff]

Ok this is a long shot but I want to convert the eyepiece side of the Baader wedge to 1.25" to give more infocus than the 2" allows; I have the bits but try as i might I can't seperate the ND3.0 filter from its Threaded sleeve. The Continuum filter was easy to unscrew but the ND3 just won't budge.

 

According to Baader and the manual it should be removable so I can move it over to the 1.25" setup. The manual shows how if it unscrewed that is.

 

Appreciate any non-distructive ideas. 

Cliff

 

 

[TerryMcK]

Not too sure Cliff as I actually have the Altair solar wedge. It might be held in place with tiny grub screws or as you say glue something like thread lock. If the latter a filter clamp might give you enough leverage to budge it.

[Cliff]

Thanks Terry,

 

I tried a similar thing with strap wrenches though mine are large, no grub screws just a 2" Baader ND3.0 filter screwed into an all threaded sleeve.  I have tried putting it in the freezer for a while that didn't help.

 

The only other thing is I have a hot air gun , I know from my days at work that sometimes loctite is used and heat will generally break the seal.

 

The Filter clamps are a good idea have to get some for 2" filters . Any links ?

 

Appreciate your suggestions,

Cliff

 

 

[Nightspore]

I'm not sure if this helps. There is a theory that 2" filters often flex slightly while being unthreaded and can seem stuck fast. Excessive force doesn't always work. However, I've discovered that very gently unthreading 2" filters can prevent the 'sticking'. By slowly and more gently unthreading the filter it doesn't flex and therefore won't (or shouldn't) stick. I find this works when unthreading 2" filters from diagonal nosepieces. 

[Cliff]

I've tried the gently approach , but no go 

Just ordered some filter wrenches to try them as Terry suggested

 

The official word from Baader in Germany was to use rubber gloves ?

 

 

 

 

[Nightspore]

2 hours ago, Cliff said:

I've tried the gently approach , but no go 

Just ordered some filter wrenches to try them as Terry suggested

 

The official word from Baader in Germany was to use rubber gloves ?

 

 

 

 

 

Maybe you can use the gloves while using the wrench lol. TBH Baader say a lot of things that seem odd to me. My favourite was when they claimed that a lot of their prisms and mirrors had always used BBHS coatings, but they didn't actually state it as silver had a bad reputation for degrading. I suppose there's a logic to that, somewhere. 

[Cliff]

Or cut my losses and buy a 1.25" Lunt , I think that would still be ok with a 110mm F7 scope

And I could buy a CaK one with the remainder. ? 

The Baaders are rare as here 6months to get this one so should sell easily if need be ?

 

Interesting on the BBHS I have a 2" Amici prism with those coatings no problem as yet. I believe it is a Zeiss prism.

 

 

 

 

[Nightspore]

2 hours ago, Cliff said:

Or cut my losses and buy a 1.25" Lunt , I think that would still be ok with a 110mm F7 scope

And I could buy a CaK one with the remainder. ? 

The Baaders are rare as here 6months to get this one so should sell easily if need be ?

 

Interesting on the BBHS I have a 2" Amici prism with those coatings no problem as yet. I believe it is a Zeiss prism.

 

 

 

 

 

I have the 2" & 1.25" Baader BBHS Amicis, plus 1.25" BBHS mirrors (sital & dielectric) and the conventional BBHS prism. I believe the degradation problem was solved a while ago. I was using the 1.25" prism only a few hours ago with my 72ED DS Pro.

 

 

It's difficult to beat a silver coating. The Amicis are 'Zeiss specification' I'm not sure where they are actually manufactured. Baader have a lot of stuff made in Singapore. 

Edited June 11, 2022 by Nightspore

[Cliff]

Ok until I can remove the stubborn ND3.0 filter I have put the ND1.8 and ND0.9 ( about ND2.7 total ) in the 1.25" adapter should be ok for photography less the Continuum filter. Not sure its safe enough for visual ?

If it's still too bright with the 174mm maybe I can add a polariser or green filter to the camera side.

 

I was reading a IRPASS filter can also help. Have a 742 and a 850nm one if I remember.

 

Now if the heavy wind stops ?

 

[TerryMcK]

With the 174mm you can turn the gain down and decrease the exposure time. I only use a continuum filter and ir/uv cut filter. The Altair wedge has a polarising filter that darkens the image.

I take a short video capture of around 1000 frames with Sharpcap after adjusting exposure etc whilst watching the histogram. Then the resultant video is processed with AutoStakkert to select the best frames and it then stacks them into a static image.

[Cliff]

Hi Terry,

 

Yes I know I have used the 174mm for a while (with SCT with Baader film and also the Quark on the smaller refractor ) though not much with the wedge yet , I'm surprised a UV/IR and Continuum filter are enough though you mention the polarising filter so I could use one on the front of the camera. Depends on the Scope aperture also much more light in the 110mm than my 76mm.

I'll let you know how it goes once I get a clear wind free day ?

 

[Cliff]

Just a quick follow up The Baader 2" wedge with the ND1.8 and ND0.9 still too bright for the 174mm

Also the ND1.8 and the Continuum also too bright so added the 1.25" polariser to the camera and managed a decent exposure. Rotating the camera gave a wide brightness range using the polariser.

 

This is on my 76mm doublet also haven't tried it on the 110mm yet. 

Getting there.

 

[Cliff]

ND3.0 Filter still stuck even after using the lens wrenches suggested by Terry. 

 

 

[Carbon Brush]

If you have to go down the route of buying another wedge, why not Lacerta?
I have a Lacerta 2" Brewster angle and have been happy with the results.
They are much more affordable. I haven't though done a side by side.
However, I have read reports on another forum about Lacerta not being 'worse' than Lunt or Baader.
Just a thought.
David.

[Cliff]

A solution to my issue, bought a 'lens spanner' and swapped two of the ND glass filter cells over. problem solved.

 

The ring is still stuck to the ND3 lens cell but i'll try a few things now there is no glass in it.