John

Caught Comet C/2023 A3 Tsuchinshan-ATLAS with my ED120 refractor this evening. Seems to be around magnitude 10 and situated in Virgo around 2/3rds of the way between Porrima and Heze, close to a faint triangle of stars. Does not jump out with this aperture at 64x and could be mistaken for a galaxy, especially in this part of the sky. A faint, rather small fuzzy elongated patch of light.

Nice to see it though 🙂

5 hours ago, Don Pensack said:

They are used only for planets or close double stars, so the eye is held back far enough the field size is reduced.

Only recommended in scopes that track.

I had the TMB Supermoncentric 5mm for a while. Superb high power eyepiece but with a ~30 degree AFoV and around 3.5mm of eye relief, challenging to use with my undriven scopes. The University Optics HD 5mm ortho that I also had at that time was as good under moderate to normal skies but the TMB SM showed just a little more under better skies, which means around 15% of the time.

These days I'm happy to sacrifice a little in performance for comfort 🙄

Interesting report 🙂

Smoothside TV plossls were the 1st 1.25 inch eyepieces that I ever bought - when I migrated from .965" ones way back in the late 1980's

The TAL 25mm is no slouch though so it shows that TV was doing something right with their version of the plossl design.

The odd thing is that you don't hear any complaints about eye relief from owners of Zeiss ZAO ortho, TMB Supermonocentric or Pentax XO eyepieces, which are very tight in the shorter focal lengths. Presumably the optical performance of these legends is so good that the effort required to use them is worthwhile 🙂

On 02/05/2024 at 02:26, Sunshine said:

Oh I have everyone beat, about three min to put my scope out and get an eyepiece in it. Visual astronomy is a beautiful thing!

We will call it a dead heat then 🙂

https://stargazerslounge.com/topic/421727-telescope-setting-up-time/?do=findComment&comment=4482814

NPL's are plossls. Plossls and orthos have eye relief that is around 75% of their focal length. 

Luckily for us today there are plenty of designs that offer much longer eye relief but there are usually additional glass lens elements involved in achieving that, so additional weight.

I have a 4mm HD ortho which has eye relief of 2.7mm I believe. I do use it very occasionally but never for long to be honest. Optically it's excellent but I soon get tired of trying to hold that tiny exit pupil while tracking and the AFoV is just 40 degrees. 

Even the Nagler 4mm-2mm zoom seems comfy after using the 4mm ortho !

Meade used plastic dew shields and objective counter cells on some of their refractors so I guess balance plays a part in the choice of materials used.

Meade made their refractor dew shields generally a bit on the short side though. Maybe that was also a weight saving move ?

All the Skywatcher fracs I've owned have used metal dew shields. With my ED120 it screws off but I need to add an Astrozap dew shield extension in dewy conditions and fortunately those are quite light.

Interesting what we start mulling over when it's cloudy 🤔

Some good advice on collimation above.

My advice is initially to concentrate on getting the finder scope accurately aligned with the view through the main scope, fully extending and locking the flextube rods and ensuring that the correct adapter is being used in the focuser (earlier posts cover all these things).

4 hours ago, LukeTheNuke said:

Gosh, I need a brass telescope one day! Posh mount, too. My dad had some brass telescopes up in the loft, as he collected antiques. I asked him if he'd ever tried doing some stargazing with them. He said to me, "I couldn't think of anything more boring!" I dunno what happened to those scopes. Well this doesn't look like a fast scope. What's the focal ratio? I'm guessing it's not a Coronado! The finish does look up a notch...

It's a 3 inch F/16 achromat. The objective is a Carton from Japan. The scope was one of the final batch made by Ernie Elliott of Broadhurst, Clarkson and Fuller at Telescope House in the Farringdon Road, London in 1992. The design has been used for around 250 years I think 🙂

About 3 minutes but I don't image, don't use GOTO and use alt-az mounts 😁

4 hours ago, josefk said:

Great list @Size9Hex - Barnard's Star is in a recent Sky & Telescope and it IS appealing to mark something like that over several years and have a little arc in the sky on an atlas (or series of sketches) representing decades of observing.

Zeta Herculis is a candidate for this. I posted a rough sketch and an update of it, made 4 years apart, in this thread that @Nik271 started in 2020:

https://stargazerslounge.com/topic/362978-zeta-herculis-at-last/?do=findComment&comment=3955182

Time for another update to this sketch now - a further 4 years have passed and Hercules is again rising into a favourable position for observing 🙂

Great setup Neil 🙂

Do you leave the Tak tube clamp bolted onto the side of the mount and lift the scope tube in and out of it ?

I've just realised that I could take that approach with my FC100-DL and the Skytee II but wonder if it's more or less hassle than using a DT bar bolted to the Tak clamp, as I do now 🤔

Really nice sketches - they capture the look of these binary stars through a quality refractor perfectly !

4 minutes ago, Size9Hex said:

First post for a while with observing having taken a back seat to other things in life recently, but a very inspiring thread with some awesome sights. A handful from me that I don't think I've seen mentioned above:

• Pillars of Creation. I've looked for it in a 10", but not successfully seen yet. One day!
• Half illuminated Jovian moon. I think I saw on odd elongated shape to Europa a number of years ago as it emerged from eclipse over the duration of a minute or so. Would love to repeat this and get more confidence. Feels more doable than albedo features on Ganymede which I've definitely never seen (but others have), but that could be another one for someone's list - features on a moon around a planet other than ours.
• The bright glob (G1?) associated with M31 was a nice bucket list tick as a glob outside our own galaxy.
• Valles Marineris on Mars. I spent some time looking for it a number of years ago and I think I detected something linear in the right place. From research afterwards I concluded that observing the Valles is implausible, but that the albedo feature surrounding the Valles is plausible. Would love to repeat this and gain confidence. Such an iconic feature in the solar system, even if only observable in a very loose sense as the surrounding albedo feature.
• The large scale structure of the universe. Spotting lonely galaxies in one of the big voids, or a bright galaxy off in some giant filament somewhere. I've had one or two of these on the list from time to time but can't recall the catalog IDs - and success is definitely hit and miss! I'm completely out of my depth on this topic, but interesting to look for the visible parts of structures that are (1) unfathomably far away and (2) span seemingly across the entire night sky despite this!
• Evolution of something in the night sky outside our solar system. I've never had the persistence or patience, but would like to feel like I'd seen orbital mechanics at play in a double star system over a few years. Barnard's star comes to mind too. Timelapses of M1 evolving over 2 decades or so - superb effort by the imagers, but I wonder if it's a plausible lifetime project for a visual observer/sketcher!
• The star associated with Cygnus X1. Easy observation. No sight of the black hole of course, but iconic, and worthy of a place on the bucket list for me.
• Central Milky Way from a long way south under superb dark and clear conditions.
• Solar eclipse. Need to plan ahead and make sure I'm in the right place at the right time before I run out of chances!
• Northern lights. Another one for the future.

Thats a great list Paul 🙂

While on Mars, I believe the clouds that accumulate over the Olympus Mons volcano are visible in amateur scopes under favourable conditions. Is the volcano itself I wonder ? - not sure but it's the biggest in the solar system, I think !

13 minutes ago, Epick Crom said:

Hi John. I recall that you had a 12 inch dobsonian. Have you sold it?

 

Joe

Hi Joe,

Yes, back in spring last year. It was a great scope and I had a lot of fun with it for over a decade but now having grandchildren running around the place, the big old dob was likely to prove too tempting for little hands to explore. It's easier to keep my refractors out of harms way so I decided to let the dob go to a new home.

I may well get some larger aperture again in due course. If we start to get some nice clear, dark nights again the urge will grow !

I completely forgot to look out for Comet Tsuchinsham-Atlas when I was browsing around Virgo last night 🙄

I'll have to pop a post it note on my eyepiece case to remind me to look for it next time out !

We have a 12 inch Meade ACF in our society observatory. I've not used it myself but those that have (primarily the imagers) seem pleased with it.

22 minutes ago, Mr Spock said:

When I use the Nirvanas, they are all nearly par focal. So I leave it at that focus and slip the 42mm in part way until it's focused. Whether I use the 16mm Nirvana or the 17mm LVW as an intermediate, going to the 8mm of the Svbony is a huge amount of in-focus. Given the brightness of stars I'm looking at I can't even see if they are there they are so out of focus.

There is a considerable amount of difference in the focal plane position with eyepieces of different designs and brands. I usually use a Pentax XW before stepping down to the Svbony 3-8 zoom and there is some further inwards focuser movement needed - maybe 4mm or so ?

If I need to step down further than the Svbony 3-8 goes I generally go to the Nagler zoom 2-4mm which needs around 10-12mm outwards focus movement. 

I find that slightly annoying, but, having always had a wide range of eyepieces in my case, I'm kind of used to it 🙂

Maybe I should move to TV Delos's from the Pentax XW's and then I could have a set that is totally par focal from 24mm (Panoptic) to 2mm (Nagler zoom) 🤔

Hint: don't try an APM super zoom in 1.25 inch mode - that really will annoy you 😉

15 minutes ago, Mr Spock said:

I very quickly gave up on using it for double stars. The change in focus is too much of a jump from my other eyepieces and I just got annoyed with it. My old set up of 42mm LVW as finder, then 16mm, 7mm(8mm), 4mm Nirvanas works perfectly for doubles so I've been using that tonight.
As I have better planetary eyepieces at 8mm, 6mm, 4mm, 3.5mm, I shall probably end up selling it as it isn't going to get any use.

I found mine excellent again tonight. Very nearly par-focal from 8mm to 5mm I felt with a small adjustment moving to 4 and 3mm (3.5mm really). The Nagler 2-4mm is almost perfectly par-focal across it's range but the Svbony is not far off, IMHO.

That was in an F/7.5 120mm refractor. 

Still, it's not going to suit everybody, granted.

I did like the 4mm Nirvana when I had one a while back.  

Still very nice here but I'm a bit tired so I've packed in now. Finished my very pleasant session with a 3rd planetary nebula, NGC 6826, the "Blinking" planetary in Cygnus. It wasn't blinking this evening so the transparency must be quite good. Central star nicely seen.

Still got a touch of aperture fever though - it would be a good Virgo / Coma galaxy night here with 10/12 inches of aperture 🙄

Still nice and clear here 🙂

1st decent view of M57 this season, which was nice.

Pleased to catch M13 and the mag 11.8 galaxy NGC 6207 in the same field of view with the ED120. Galaxy rather challenging but M13 is well resolved (for the aperture) at 150x.

The "Cats Eye" planetary nebula NGC 6543 was looking quite bright in Draco. 

Had a few glimpses of the brighter Markarian Chain galaxies in Virgo as well. Caught a touch of aperture fever with those, recalling the views I used to get with my 12 inch dob of the chain - 10/11 galaxies in a single field. Still, the 120's doing it's best 🙂

Nice and clear here at the moment. ED120 takes a turn tonight. Well known doubles currently the targets. Maybe more ambitious targets later 🙂

I remember seeing a Meade Lightbridge 16" at a show somewhere and thinking that there is no way that I could manage that on my own and not having a roll-off shed or similar to keep it in. The StellaLyra 16 will be a similar size and weight I would think. Made by GSO as well.

I bought a Lightbridge 12 in the end but that was too heavy for me as well so had to go. Eventually I put together my 12 inch Orion Optics based F/5.3 dob on a custom base which weighed the same as most chinese 10 inch dobs and that was a breakthough for me. As quick and easy to set up as my refractors and capable of going a lot deeper. 

I did wonder about an Orion Optics 14 inch at times but could not convince myself that it would get the use that it deserved. 

We have an 18 inch NGT newtonian at my society observatory which I can use and that is in a roll-off shed. That will be satisfying my aperture cravings from now on I think.

1 hour ago, LuxAltera said:

I have friend who could machine some parts for me but I can't find the perfect bearing to fit. the hole that should fit these bearings is exactly 25mm could you measure your bearing outer diameter for me?......

The outer diameter of the bearing on mine is 22mm. Not the correct size I'm afraid. I measured it a number of times to be sure.

To be clear I have measured the diameter of the bearing shown by the yellow line on this photo:

5 minutes ago, Vic L S said:

When buying/ selling there, are you meeting in person, or posting? Payments wise - PayPal? 

I've met up with folks for larger items (scopes and mounts). Smaller items have been posted. I've used Paypal, bank transfer and occasionally cash.

I sell there as well as buy there, taking a similar approach.

Around 80% of all my gear was bought used and much of that through UK Astro Buy & Sell.