John

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.

Just now, KevS said:

Business opportunity springs to mind: Do you think there is any market in producing bogus, hum adjusted receipts from FLO and similar astronomical retail outlets. They could be left around the house in full view of "significant others" to reinforce how cheap astronomy actually is🤣.

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

1 hour ago, cloudsweeper said:

Wonder where you with your expertise would place EPs? .......

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

20 minutes ago, Ruud said:

Suiter must be wrong.....

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 hour ago, F15Rules said:

That's interesting John..I have seen one of these (and looked through it, although an unbranded version and not the 16mm that Ian bought from me)..I didn't realise that it might have similar optics to the Fullerscopes eyepiece, but what I do recall is that the build quality was not a patch on the Fullerscopes Japan unit, although the optics seemed pretty good.

I'm sure I read somewhere that, back in the 1980s/90s, these eyepieces were quite expensive to buy new (like most Astro kit from Japan in those days?)

Dave

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

22 minutes ago, tooth_dr said:

Is it light gathering that is halved? So like comparing 6” with 4.25” rather than 3”?

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

I've tried binoviewers a few times and currently have a set of the William Optics ones on loan from FLO.

I've not really taken to them to be honest. I get nicely merged images and the view of the moon (for example) looks nice with both eyes but I've not felt them to be something essential in my toolkit.

Maybe I'll become converted someday ?. Or possibly not.

1 hour ago, merlin100 said:

Do finder scopes when focused relatively close up to something exhibit a form of parallax error?

Its best to align them with the scope optics using as distant an object as possible just for this reason.

Just another note on aligning the mount with Polaris before observing - a rough alignment of the right ascension axis with Polaris is sufficient for visual observing. I find that getting the "north" leg of the tripod (arrowed in the pic below) pointing in the direction of Polaris is sufficient to give reasonable tracking for visual observing.

Imaging is different - the alignment needs to be much more accurate which is where the small telescope built into the RA axis comes into play.

11 minutes ago, Anthony1979 said:

Thank you.... Is that dovetail bar clamped correctly... it just doesnt seem right... Wont the scope slip off

You have got it right. It does seem a fairly basic way to mount a scope but it is the way it's generally done.

Tighten the clamp and the smaller security screw onto the bar firmly. It will mark the bar but thats what the bar is for.

4 minutes ago, niallk said:

The Pan24 was my choice for my 10" f4.7.  No balance issues... just trim your eyelashes!! 

I was also thinking that the Pan 24 ticked all the OP's boxes with the exception of eye relief !

Plus he already owns one .....

5 minutes ago, AdeKing said:

I didn't even know meteoblue had that function available. 

It shows me that best for me is Cranborne Chase so will keep an eye on all weather sources and work out where will be best. 

Feeling more positive now than I was this morning. 

Yes, things a looking a little brighter here on Monday afternoon too.

8 hours ago, Nigella Bryant said:

Weather forecast better for the south west of England now but time will tell. 

Sounds hopeful. I'm sort of in the SW but I can go further !

Getting eyepieces that are wide, well corrected at F/4.7, have decent eye relief and are light in weight is a tough order. To get the well corrected performance at fast focal ratios and good eye relief, quite a lot of large glass elements are needed with some radical curves on them and those are what weighs the most of course.

Of those discussed here, I've owned the Nagler T4 22mm and thought it a very good performer and comfortable to view though. 

I now use the Ethos 21 and a Nagler 31 but those are definitely in the heavyweight category.