John

6 hours ago, Nigella Bryant said:

I've just come across those in good condition on fleebay so bought those to, to compliment these. 

I love both the artwork on them and the notes on the back of the cards. In many cases they really emphasize how far our understanding has come since they were issued in 1928

I had the 4mm Nirvana for a while and it turned out to be an excellent high power eyepiece

They look great !

I have an old set of the Wills Cigarettes "Romance of the Heavens" cards somewhere - getting those mounted would be a nice winter project - thanks for the inspiration

Personally, I don't use a filter to view Venus.

I do try and catch it when there is as much daylight still in the sky as possible though and, for me, that is the best time to observe the planet.

Seeing surface or cloud top features on Venus is very challenging I've found. 

32 minutes ago, Nik271 said:

I just came back from  a couple of hours of great seeing. Saturn and Jupiter were fabulous but I concentrated on Neptune. Had my highest power EP, 6mm giving x450. It got easier as the time went on, the best moments were around 10pm when I could see Triton with averted vision for long periods of time. It's on the opposite side to Neptune from the 6th magnitude star, and about 1/6 of the way out. There is another much easier 12th magnitude star further out.

I'm thrilled, Triton was only discovered in 19-th century with a much bigger telescope!

Great stuff Nik - well done !!!!

23 minutes ago, ScouseSpaceCadet said:

I was using goto and Sky Safari at the time John. Observing Jupiter, looked at Sky Safari, saw the Saturn nebula was close by, hit goto and straight to a new object to me. 😀

I was thinking more of the things you come across while star hopping. Things that you didn't realise were there until you stumble upon them

I love those "accidental findings" as well

Another reason why I don't use a GOTO system. Maybe there is one now that has a "stop at interesting places on the way" option ?

59 minutes ago, JeremyS said:

Never having attended one, Are SGL star parties camping only or are there lodges at the venue too?

I’m not a camper.

They have some glamping huts and pods for hire.

I used to take our caravan although I did camp for the first one that I went to - in my daughters tiny guide tent ! It was a clear but cold April and I have never spent such a cold night

After that it was our caravan, with a nice warm heater and comfy bed. Sadly sold a couple of years ago

Much of the star party could take place in a socially distanced manner but the moving from scope to scope enjoying the different views part might have to be compromised

1 hour ago, F15Rules said:

That's amazing performance, John! At 600x you must have been almost constantly turning those big slow mo's!😱😂

 

 

Indeed - 50 degree AFoV as well with the Nagler zoom

Fortunately the slow motion controls of the T-Rex are very smooth and create no vibrations in use. It's not exactly a relaxing pastime though

4 minutes ago, Andrew_B said:

....Lens design is done in-house, as is manufacture of lens cells and the grinding and polishing of mirrors.

Do they make the glass as well ?. I believe they do with Fluorite but how about the glasses used in the TSA and TOA refractors ?

While they share the orthoscopic characteristics of a relatively narrow apparent field of view and eye relief which is at best 80% of the focal length, the Baader Classic Ortho 10mm and 18mm eyepieces are really excellent performers, way above their purchase price.

That said, I spent some time comparing the 8mm BST Starguider with my 8mm Tele Vue Ethos in my 12 inch F/5.2 dobsonian a while back and found very little difference in terms of optical performance. The Ethos just provided it over an additional 40 degrees of field of view.

In terms of light scatter control (which can be important for planetary observing) the Baader Classic Ortho would be (as it should be) slightly better than the more optically complex BST Starguider. They will also have slightly higher light transmission.

There are some good options for around £50 apiece these days

My brother is called Alan - so I know who to blame !

21 minutes ago, jetstream said:

Vision, the big unknown. Good point actually- John can you see the Double Double in Vega as 2 separate "stars" naked eye?

I don't know, I've never tried. I suspect not but I'll have to try it at the next opportunity.

I think I used to be more fussy / ambitious / discerning over optical performance in the past than I am now. If I get nice views and occasionally see something that I've not seen before then I'm a happy camper

My observing eye is clearly not as acute as some here. I've compared my T2 BBHS prism with my AP and TV diagonals quite often and I just can't see any differences in performance in any of my refractors

Probably not much point in me trying a TOE - I probably won't see any differences over my current high power eyepieces !

I struggled to see much difference between a TMB Supermonocentric 5mm and a University Optics HD 5mm ortho when I had those in my eyepiece case. Only perhaps on the nights of very best seeing and then the differences were very subtle indeed.

11 minutes ago, jetstream said:

Dont you just love those .2mm exit pupils?

I'm actually not that keen on using ultra-high magnifications. When observing the planets I will always prefer smaller / sharper / more contrast over a larger image scale. I have found very high magnifications useful for some tasks though so it's good to have instruments that support that, when required.

11 minutes ago, Deadlake said:

Do you think this is the limit?

I've honestly no idea. Without using a barlow, my shortest fl eyepiece is 2mm. I don't use that very often but on the right sorts of targets and under the right conditions, the optics of the scope seem willing. With the Baader Q-Turret barlow I could get to 1350x - I might give it a go for a lark sometime

17 minutes ago, Deadlake said:

You mean TSA120 are so common 😀 Seriously I wish I had a good night’s seeing to give an accurate report and a BBHS mirror diagonal. Given I’ve almost got all the parts for using the AZ100 I predict clouds….

I was using 600x on tight double stars and to spot Triton last night with my LZOS 130. 240x seemed the best for Jupiter and 300x did well on Saturn. Your LZOS (and @Stu's) are very similar optical quality I think. If you get the seeing, pump up the power ! 

Hope you get some good sessions in with the scope soon

A question for TSA 120 owners if I may: We know that Canon Optron make the objectives for the Tak Fluorite doublets. Do Tak make their triplets (such as the TSA) themselves or is a third party optical house involved for those ?

Edit: Just found the answer from Roger Vine's review of the TSA 102: "The TSA-102’s lens is an air-spaced triplet made in Japan by Canon/Optron"

49 minutes ago, Dark Vader said:

I finally managed to bag Neptune last night after numerous attempts. Shouts of "yes" emanating from the darkness in the back garden at Vader Towers. 

Now, I'm not certain about this next bit. Just a fraction up from Neptune (dob view) was the faintest point of light coming in and out. A check on Sky Safari and it was where Triton was meant to be. I was only at 180x and I've read that it can take in the region of 300x for Triton. I tried upping the mag with the BHZ and 2.25 Barlow but the image was too dim.

Is it possible at 180x in an 8" Dob, or wishful thinking?

It's quite possible with an 8 inch dob I'm sure. I would think more magnification might be needed to tease out the faint point of light but, you never know 

Last night Triton was on the opposite side of Neptune from a magnitude 6 star which would be appearing in the same high power field of view. Triton was around 10 arc seconds from Neptune's disk:

This is the newtonian view at high power from Cartes du Ciel:

I've compared a Baader T2 Zeiss diagonal with an Astro Physics Maxbright in my F/9.2 LZOS 130 a few times on a variety of targets but I have not seen any tangible differences.

Off the original topic though so apologies to the OP.

When there is a bright moon close to them in the sky, I've found the colour of both Neptune and Uranus more vibrant than when they are against a pitch black background.

I assume this is a similar effect to that which makes Jupiter seem more contrasty and colourful when observed against a twilight sky.

The downside of a brightly moonlit sky is that it makes finding the fainter planets that much more challenging !

Interesting report Mark

The seeing tonight was excellent and judging by the views I had with my 130mm F/9.2 LZOS, I'll need to buy all 3 TOE's

I had to "slum it" with the XW 5mm and 3.5mm and the Nagler 2-4mm zoom tonight though

Reminds me of the movie "The French Lieutenant's Woman".

When the film was first released we saw a midnight showing at Lyme Regis cinema and then walked down to the Cobb in the moonlight

6 hours ago, John said:

I have seen Triton with my 130mm refractor on a couple of occasions when the transparency was good and it's elongation from Neptune favourable.

It's relatively straightforward now with my 12 inch dob.

I've found the Uranian moons slightly harder - I've only managed to see 2 of the 4 that are theoretically visible with my 12 inch.

 

I managed to get Triton again with the 130mm tonight:

Just managed to get Neptune's moon Triton with the 130. Rather pleased with that - it's mag 13.4 dimmed to  13.7 by atmospheric extinction according to Stellarium but the limit for 130mm aperture seems to be 13.4 according to the calculators 

I've no doubts that I've picked up Triton visually and it's position corresponds with Stellarium and Cartes du Ciel. Needed lots of magnification - 400x and even 600x used (crazy !!!).

Perhaps Stellarium's estimate of dimming is too pessimistic ?

Anyway, nice to spot Triton with the 5.1 inch scope

Just an additional note on this. The Oval BA used to be a red coloured storm system, maybe the one sometimes called "Red Spot Jr" ?. It has changed it's colour over the past few years becoming pale / whitish recently. This has attracted the attention of researchers who are trying to work out the reasons for a "Temporal Evolution" of this systems colour.