I want to complete the eyepiece collection in the near future. I already have the TV 22 and TV12 Naglers. The 17mm will join them.
I am not sure about the 8mm. Tack sharp images to the edge and
generous eye relief are more important than 82 degrees of field.
A 2" barrel would be nice, I would only need one filter!! I am not sure if any eyepieces in this length have this feature. I rather like the LVW and
Pentax for sharpness. Thanks, Paul.
Ethos 8mm is 1.25'/2". An EBX-2120 barrel extension allows the use of a 2" filter
.
Radian 8mm is 1.25" only but you can leave a permanent 2"-1.25" adaptor on the eyepiece.
16mm T5 Nagler with 2x Powermate is 8mm and 2" but not as much eye relief.
32mm Plossl with 4x Powermate gives plenty of eye relief and a big eye lens and is 8mm and 2" barrel.
40mm Plossl with 5x Powermate gives plenty of eye relief and a big eye lens and is 8mm but 1.25" barrel.
31mm Nagler with 4x Powermate gives plenty of eye relief and a big eye lens but is 7.75mm. (2")
35mm Panoptic with 4x Powermate gives plenty of eye relief and a big eye lens but is 8.75mm. (2")
Plenty to choose from, depends on how much you want to pay. The tack sharp to the edge is what you are paying for.
Try my 8.5 xf paul its got most of what your after and is surprisingly cheap .
Sold on a 7mm nagler to get this one as I think this magnification gets a lot more
use with our skys .
Most 2"/1.25" adapters are threaded underneath for 2 " filters
been using my 2 " filters on my 14 xw switching to 22t4 for ages without any dramas.
GRAHAM -
Thanks, we must get together for an observing session! I like the sound of the Pentaxes, with their sharpness and eye relief. The Radian and LVW are the other favourites. Where did you get the adaptor? There is a Televue adaptor around, but no filter thread. If I am to get a good filter, Lumicon or Astronomik, I only want to pay for one!!! I will phone Bintel and ask about using the Radian in a 2" barrel threaded for filter, if it is possible.
PETER,
Do you have the LVW? If so, is it a 2"?. Thanks, Paul.
LB,
No, its only a 1.25". Its pretty hard to find high power EP's with 2' barrels. Does your diagonal have filter thread? If not consider getting one that does, that way yhere's minimal faff.
Als all the EP's I've mentioned I no longer own, tho I'm planning to splash out on the Pentax come pay-day!
Be careful. A few 1.25" eyepieces have barrels long enough to hit a 2" filter screwed into a GSO 2"-->1.25" adapter. I recall that some GSO plossls would do this. I recommend that you check carefully in daylight with the eyepieces you plan to use this way.
Thanks, Eric. I notice that Televue do not include filter threads on their adaptors, just in case someone slides a great long barlow or similar into the adaptor and crunches an expensive filter.
Thanks, Eric. I notice that Televue do not include filter threads on their adaptors, just in case someone slides a great long barlow or similar into the adaptor and crunches an expensive filter.
Yes, my 1.25" TV 3x barlow would leave an impression on a filter! Hadn't thought of that!
I phoned Bintel to check on fitting a 1.25 eyepiece with a sleeve for 2". They didn't know, but took my number and phoned back in 5 minutes. Yes you can fit a $19 Bintel 1.25 to 2" adaptor to a 8mm Radian and fit a 2" filter on the end without the eyepiece hitting the filter, just as Graham suggested in his post. As long as you keep the long nosed barlows away. Good answer!! Just another example of their great service. The Bintel boys were all getting primed up to drive 3 hours to a dark sky site and observe until 3 am. Good stuff.
