PDA

View Full Version here: : 27 Pan-Spoke too soon!!!


Waxing_Gibbous
16-10-2009, 09:55 PM
In another thread I was cogitating and fussing on which wide-field EP to get that would go with both my f5 dob and my f9.2 refractor.
Well my wife showed up from work bearing goodies. Some v. nice sushi and a 27mm Panoptic!!!! :D Not in the same box of course.
From the roughly 17 minutes of cloudless sky we've had tonight, I must pronounce it "fit for purpose"!
Much lighter and easier to use than a Nagler 26 or a 35 Pano (the only other WFs I've spent any time with. Initial impressions are consistant with its rep.
Sharp, flat, field to about 95%, no obvious CA and no scatter that I could see.
The oft quoted "sea-sick" effect while panning did not materialise.
A keeper.
Well that's my eyepiece collection sorted!

I think I'm pretty much done buying gear.

Weellllll, except maybe a wafer-thin, go-to mount, a red-dot finder, maybe a pre-loved MK67, or a TMB 92. Perhaps I'll just dabble in astrophotography....:P

It never ends.:D

Addendum:
Woe is me!!! I tried the 27 in my older Meade refractor the other night but not in the dob until just now. I can't for the life of me get it to focus. No problems with any other EP (32 GSO, 19 Pan, 20Plossl).
The Meade has a fairly long (4"+) R+P focuser, the Bintel dob a very short one. Could this be the trouble or could the OTA be to short?
I've never heard of this before with this EP.
Any thoughts?

Paddy
19-10-2009, 11:44 AM
Now that's a fantastic solution Peter! I'm glad to hear that your new ep is so pleasing, and of course not at all surprised.

BerrieK
19-10-2009, 01:41 PM
What a nice wife!!

Kerrie :)

Waxing_Gibbous
20-10-2009, 12:29 AM
The BEST!

Saturnine
21-10-2009, 01:10 AM
Hi Peter

Just read about your very nice present, the 27mm Pano is a damn fine eyepiece, I really like mine and like most eyepieces the longer the focal length of the scope the better they perform but it's a hefty blighter for its size. I just briefly checked mine against a 30mm Superview and it requires an extra 25mm of back focus in an F8.8 refractor and if memory serves me correctly, in my F6 dob the Pano also needed plenty of back focus compared to most of my other eyepieces.
You may need to get an short extension tube so that you can then rack the drawtube in further than usual.
Hope this helps to possibly explain your not being able to achieve focus, yet.

Regards

Jeff

Waxing_Gibbous
21-10-2009, 08:21 AM
Jeff,
Thanks. I was hoping this was the case and that it wasn't a problem with the EP or tube. It's just odd that in all the reviews of the 27, I've never seen this mentioned.:shrug:

dannat
21-10-2009, 08:24 AM
you might need an extension tube - you may have to try different ones.. i used a 35mm

Paddy
21-10-2009, 10:03 AM
If it's not too far out, you could adjust all the collimation screws by an equal amount to move the position of the primary. I had the same experience when I first put my WO 28mm UWAN in my 12" dob.

Waxing_Gibbous
21-10-2009, 10:42 AM
Patrick,
Ta. I'll try an extension tube first as I've got one lying around somewhere "safe".

erick
21-10-2009, 10:44 AM
Can I get my wife to talk to your wife for a bit of education?

Waxing_Gibbous
21-10-2009, 12:47 PM
I believe she thinks it worth it to stop me binding-on about which whatever I should get next.:lol: Extremely thoughtful nonetheless!
Hence my horror at not being able to focus in the dob. I would cut off my arm before I let her think she got it wrong!
But we both fuss over what "stuff"to get.
Other favorites include:
Tractors, sheep breeds, printers, ovens, pianos, pottery kilns, arcwelders,
wide-angle lenses, FF DSLRs, software, roof insulation, decking & pheasants.
All of which have been 'under discussion' for the last 3 years!

taminga16
21-10-2009, 01:13 PM
Peter,

You could always drop the lens element from a Barlow and slide the barrel (with the Pano installed) up and down in the foccussor to determine the length of the extension tube that you might require.

Greg.

erick
21-10-2009, 01:31 PM
If a 35mm extn will do, PM me - I have a spare one you can have for the cost of a postbag.