Explore Scientific 2" equipment help and advice (100*-eps/dia/tele-extx2)

[p14b]

Hi my name is Paul i'm to to posting on here, i'm looking for some help or advise with my set up. C-925/ CGEM-DX  i lost interest in viewing and moved over to Astro-Photography, but i recently looked through a friends scope with a 100deg 2" EP just at the moon and was blown away.This in turn has bought me back to viewing again!, my 1.25 eps are mix and match nothing stands out, but i do still enjoy my cheap SW Bino-Viewer with my 2x Baader mkIII zooms. But now feel i would like to go down the 2" very wide ep route.

I have no set up at all for 2" , But i have acquired a 14mm  Explore Scientific 2" 100deg ep, Does anyone have experience with using these 100deg eps and also if they work well with a ES-Diagonal and/or a ES-2" x2 Tele extender and also if these work will with my 0.63 corrector.

I do have a Baader T2 mirror Diagonal but not sure if i bought the 2" click-lock holder to replace the 1.25 that this would work very well it has a 35mm opening. 

Yes money is a factor "as i hate spending it" would rather by the ES 2" diagonal over the £200 Baader 2" clicklock mirror diagonal if it does not become the weak point in the system

Basically any advise or help is welcome from people with any experience of the above equipment or similar. 

Thx Paul

[John]

Hi Paul,

I've used / owned quite a lot of 100 degree eyepieces. They will work just fine with the C9.25 and a 2" diagonal. The ES 2" TeleXtender will work well too although the "stack" can get quite tall (see photo) when using this combination. I have used the Baader T2 Zeiss prism diagonal with all my 100 degree eyepieces and it works fine except with the 21mm Ethos where the apertiure of the diagonal (34mm) did vignette the field edges slightly. These items will affect the balance of your scope as well - with the 2" diagonal you might have 4 lbs on the back end of the scope.

 

[p14b]

Hi John

First of all thank you for your reply, I'm going to go for the ES-2" x2 focal extender £130ish, I here what you say about the weight, i'm not overly concerned but this does tempt me to buy the Clicklock 2" with adapter to attach to my Baader T2 diagonal, and that attaches to my scope via my T2 to SCT camera adapter (this gives me a very secure  2"diagonal)  and at least this way i can see how i get on without buying a dedicated 2" diagonal, if then i expand to other 2" eps and i then come across problems with vignetting i can use the 2" clicklock as my visual back on the C9.25 as it has SCT fitting and buy a 2" Diagonal. so nothing is lost, (come to think about it i would need a 2" Visual back if i bough the ES 2" Diagonal anyway!!) 

Hope that makes sense ! , i'll order the 2" clicklock with SCT/T2 ring-adapter and the ES 2" x2 focal extender for now and see how i get on.

I read on some forum! My T2 maxbright mirror diagonal 92456100 when using it with 2" clicklock ep holder starts to hit problems with eps with a field stop of 34mm and greater, i understand this can change depending on whats added in the light path ect ect, but if it holds true would allow me to use my ES 100*14mm with ease, and the ES 100* 5.5mm would be my next choice so that's fine, my problems would only come going the other way to the ES 100* 20mm with a 34.8 field stop. This may sound a stupid question but is field stop and the diagonal open aperture related? ie the open aperture must be greater than the field stop.  

I may regret asking that if its so obvious, but i do admit to once spending a hour trying to fix and get my live view on my DSLR on my scope to work, only to find id left the end cap on my scope.

Once again Thx

Paul

 

[John]

If there is an aperture stop / baffle / lens retaining ring etc reasonably close to the end of the eyepiece that is smaller than the field stop of the eyepiece then I reckon it must affect the amount of light getting to the outer parts of the eyepiece field of view. It might not be noticable if the difference is only 1mm or so though ?. It won't be a sharp cut off though, maybe a softening of the outer edge of the field of view.

Thats my thinking anyway - happy to be proved incorrect though