John

Thanks Raph

I realise that there is some relevance with this thread but I'm keen that we don't go off on a tangent on coma correctors when the original question was about eyepieces

I've owned both the Nagler 22mm T4 and the Vixen 22mm LVW. They are quite different designs but peform equally well in terms of sharpness across the field of view. In a F/4.7 newtonian the Nagler will show more coma though because it shows more off axis field than the LVW. Not the fault of the eyepiece but the nature of fast newtonian optics. Both comfortable eyepieces with good eye relief and large eye lenses. Quite a bit difference in price though.

I observed Comet Halley from the UK in 1986 and it was rather dull and insignificant even with a 6 inch scope.

The relationship between the diameter of the eye lens and the size of the apparent field of view is quite complex eg: my Delos eyepieces have a 72 degree apparent field but their eye lenses are about 50% larger in diameter than my Ethos eyepieces with their 100 degree fields. I believe that the diameter of the eye lens is more connected with the eye relief of the eyepiece than it's field of view. Amongst the largest eye lenses out there belong to the ES 92 degree eyepieces, which also have long eye relief, considering their very large apparent fields.

I hope you have been a good boy this year FLO list the 30mm / 100 ES at £860 and the 3 inch ES diagonal is $400 currently in the USA but I can't find it listed in the UK currently. So still less expensive than the TV Apollo 11.

Lovely images Funny how images in HA can make the surface of the Sun can look a bit like Hammerite paint !

I'll get these out of the way now before the good stuff comes in from others

So far, not too bad at all here. Managed to see an early "bite" from the solar limb as Mercury made contact and have had some nice views as the planet has tracked across the Suns disk so far. Got a few snaps with the mobile phone but there will be far better ones around soon from others I'm sure. Much better views than the single short glimpse I got of the last event, so I'm happy

Lots of cloud cover here but also some clear spots here and there. I'm hopeful of seeing something of the transit at least but it will be a case of grabbing short views rather than lengthy observation. No rain currently at least.

My other half is glad that I prefer those budget Tele Vue and Pentax eyepieces rather than the more expensive brands. So considerate of me

What scope will the eyepiece be used in ? The ES 40mm 62 is a 2 inch eyepiece as has been said.

With an 8 inch scope I'd go for a full blown UHC or even an O-III filter rather than the UHC-S. The UHC-S is designed for smaller aperture scopes but 8 inches can exploit something more effective. The cheshire eyepiece is a must have I agree. On the eyepieces, there are loads of options but the Baader zoom does deliver flexibility combined with good optical performance so it delivers value for money despite it's relatively high purchase price. The 10mm and 18mm Baader CO's are superb optically for their price but if their field of view etc don't "float your boat" then thats how it is. The Baader zoom is about the same in terms of field of view at the 24mm end (wider at the 8mm end though) so you will want a low power / wide field eyepiece to compliment it in due course. Also, with the 8 inch dob an eyepiece that gives around 180x-200x will become a staple high power tool. Happy Xmas in advance

The observatory is currently setting up a major public outreach facility. We saw the impressive observation deck that they have built when we were there in September. The 3 inch ES eyepiece and diagonal are to be used in a TEC 140mm apo refractor for widefield observing. I did wonder if they were going to use this massive kit on the Alvan Clark 24 inch refractor but apparently not. This new observing facility opened in October. We missed out by a month

I think I'm going to stay put and take my chances from where I am. Not looking good at the moment but this afternoon looks a bit more optimistic. I did get some views of the last transit so it's not the end of the world if things dont work out today.

I came across a short movie on youtube of an unboxing of a number of Explore Scientific eyepieces by the Lowell Observatory. Having recently visited the observatory I did notice some ES stuff around. I hope the observatory gets it at a good price or even as a donation from ES ! Anyway, a couple of the boxes contained one of the 30mm 100 degree 3 inch format eyepieces and one of ES's 3 inch format diagonals. I've seen the eyepiece at a couple of shows but I've never seen it in a 3 inch diagonal before. This still from the movie really brings home the size of 3 inch format kit

I'm probably not the best person to ask Doug - I'm a confirmed "occularholic"

Thats a brave statement - many observational astronomers far more experienced than myself seem to place a lot of store in his work. Not you though, obviously.

The eyepiece is pretty low down in the "wobbly stack" as Richard Suiter described in "Star Testing Astronomical Telescopes" the filters that affect the quality of the view we actually see. The top 8 from that list are: 1 Seeing (not transparency, but the level of atmospheric disturbance which distorts the image moment to moment). 2 Quality of the primary optics. 3 Central obstruction size. 4 Alignment of the optics (collimation). 5 The diagonal being used. 6 The ability of the focuser to deliver critical fine focus. 7 The eyepiece. 8 The skill and fatigue level of the observer and their eyes. Amazing that there is so much discussion of them really !

I have a BC&F brochure from 1990 which prices the Fullerscopes wide angle "plossls" as they called them at £150 apiece. The KK Widescan III's were originally priced at £160 for the 1.25 inchers and £200 plus for the 2 inch one. So they were expensive eyepieces. The chinese clones of them don't have the build or optical quality really.

I'm just hoping for a small patch of clear sky between 12:35pm and 3:00 pm-ish. I won't see the end of the transit because the Sun will have set and it's probably asking too much for clear skies for the 1st and 2nd contact events so just a chance to see the disk of Mercury against the solar disk will do for me

I've owned a few of those, some branded Fullerscope and some under other branding (University Optics). Their performance is just as Peter says. Great at F/10 or slower but flocks of seagull shaped stars star to show at the edges of the field of view in faster scopes. This I found very disctracting when I tried these eyepieces in my F/6.5 refractor so I didn't use them in that scope. At one time there were a range of focal lengths available including a 30mm in the 2 inch fitting. They originate from the manufacturer Kokusai Kohki in Japan. There was a later version of the design with improved coatings which were called the Widescan III range. They have also been copied by chinese manufacturers eg: https://www.365astronomy.com/16mm-Columbus-UWA-Ultra-Wide-Angle-Eyepiece-with-80-degree-field-of-view.html

Couldn't resist a little "dry run" in case I can find some clear skies tomorrow

Nice sunny day here at the moment - perfect for observing a transit of Mercury Trouble is .......... the transit does not start for 24 hrs 25 minutes

I started a thread on this a few years back on this topic. It might be of interest: