John

34 minutes ago, Deadlake said:

Any idea what the modern day equivalent of the Vixen ED102SS (F/6.5) would be?

I'd imagine the weight would be similar to the SD103S.

The ED102SS weighs around 4kg with tube rings and a diagonal fitted.

Today's nearest equivalent is the 102mm F/7 FPL-53 doublet refractors of which there seem to be versions by Telescope Services, Altair, Technosky etc.

31 minutes ago, Deadlake said:

What mount do you use with say a Ethos 21 and Vixen ED102SS (F/6.5)?

When I use my SD103S on a ScopeTech Zero with an APM XWA EP the scope will move any time I change an EP due to the larger then usual weight of the EP. 

I use either a Skytee II or the Giro Ercole.

The Ercole needs the axis lock to be used when switching heavy eyepieces. The Skytee II has enough "sticktion" in it's axis to handle the changeover without the need to lock the movement.

Nice report Jonathan

I used to have an Intes 6 inch mak-newtonian. It was a really excellent performer. As good as a 5 inch apochromat refractor on the planets and the moon I reckon and better on deep sky targets.

I didn't mean to alarm you. I hope everything works out really well

I'm not a regular solar observer but when I do some white light observing with my Lunt HW I've noticed that the views of the solar surface are very sharp with my Tak 100 so I agree with Stu that having good optical quality throughout, pays dividends.

On 02/06/2021 at 20:28, AdeKing said:

Delivered today a new to me 2" Celestron CG5 tripod via ABS.

This is mahoosive compared to my 1.75" EQ5 tripod so hopefully it will be more stable.

My understanding was that the Celestron CG5 is equivalent to the EQ5 so imagine my surprise when I found that the well in the top plate looked like it was dual fit EQ5/EQ6.

This was confirmed when my recently acquired Geoptik EQ6 to EQ5 adaptor fitted on top nicely.  Thankfully I picked that up used from @John

The adaptor certainly doesn't fit the well on the top of my EQ5 extension pillar with the north peg removed, so I'm well chuffed as this should fit the soon to be acquired AZ100 without the need of any mods.  

Edit: Well apart from either getting an M10 to M12 thread adaptor for the central bolt or slightly enlarging the central hole anyway.

All in all very pleased indeed and feeling like the cat that got the cream 😁

That looks good.

Couple of points but it might be me not understanding:

- the hex bolt that holds the adapter onto the top of the tripod hub needs to be flush with, or below the top surface of the adapter. It looks a little proud of that in the photo but that might be the angle ?

- you will need to remove the Geoptik M12 - M10 thread adapter as well I think.

Apologies if I've misinterpreted the photo and / or what you are saying

Forecast looks good here.

Downside is that we have family commitments now which are likely to make observing the thing difficult / impractical

Oh, well, fortunately I've seen a few other ones !

That is an interesting upgrade for the ST80. I hope the focuser can reach focus on astro targets - sometimes the 3rd party add-on focusers struggle with the ST80's with regards to inwards focuser movement.

I'd also be interesting to know what % of the field of view is sharp with the 31mm Aspheric eyepiece in the F/5 refractor.

Looking forward to your feedback from under a night sky

I've owned and used one of the TS 1.25 inch dielectric diagonals and it was both much better constructed than the stock item and, I felt, gave slightly better views - a little brighter and with a little less light scatter. Worth having at the price they are selling for.

I'm unsure whether moving to using a 2 inch diagonal (such as the Baader click-lock) is going to be worthwhile with a C6 scope though 

It's a Meade LXD 55:

You can download the manual for it from here:

https://www.meade.com/lxd55-manual-size-1-1-mb/

In the 2 inch format, the stack can be quite tall and heavy. This ES 20mm / 100 + 2x Powermate combo weighed close to 1,500 grams:

1 hour ago, Stu said:

It’s not really about focal ratio per se, more the actual focal length, although if just talking about a 4” scope then of course it is all related....

 

Good point Stu. I was assuming that we were talking about ~4 inch scopes in my earlier post.

1 minute ago, Deadlake said:

Presume a wide field scope needs a F ratio faster than F7?

It depends how much true field you want.

3.5 - 4 degrees of true field will show the whole of the Veil Nebula. I get 3.8 degrees with the Vixen and the Nagler 31. Some folks like to go as far as 5 degrees so you need a faster scope for that - something around F/5.5 or faster ?

I can bring my Ethos 21 and Nagler 31 to focus with my FC100-DL using a 2 inch diagonal. It's not the optimum wide field scope though because of the focal ratio. I have a Vixen ED102SS (F/6.5) which is my widefield frac. These eyepieces also come to focus in that with around 15mm of inwards focuser travel to spare.

NASA announces two missions to Venus:

https://www.bbc.co.uk/news/science-environment-57339355

Not launching until 2028 and 2030 though.

Great movie of the landing of the Perseverance rover on Mars included at the end of the piece 

12 minutes ago, Fedele said:

Sorry  for english

Later i will edit

Nothing wrong with the english at all - it was only the colour that I found hard to see

Nice and clear now !

I'm sure this is very interesting but the black on dark grey text is very hard to make out. Could you change that colour scheme ?

I have a 130mm F/9.2 LZOS triplet refractor and a Tak FC100-DL and the difference in performance between the two is quite obvious. Both excellent but 30mm more excellence certainly shows itself.

The ease of setup and use is also very different though with the 100mm refractor being much more of a "grab and go" affair. I need to plan sessions with the 130mm F/9.2 somewhat more.

I can imagine circumstances where a person might make the step from a 140mm refractor to a 100mm but the motives there would be more about ease of use, portability, lighter mounting requirements etc. If the step was to something like the Tak TSA120 then the performance reduction might not be as marked and maybe marginal on many targets.

The only "barlow" that I've used that seemed totally invisible in the optical train is the Tele Vue Powermate. As noted already though, invisibility comes at some cost.

5 minutes ago, Kon said:

@Mr Spock, @John and @scotty38 I still loved it and what's not to like, warm weather and seeing the sunrise later on. Saying that I would still have done it in the middle of winter. If viewing like that excites me, I am looking forward to seeing them when better placed!

Glad you enjoyed the views.

2 hours ago, Mr Spock said:

I think we have to accept Jupiter and Saturn aren't well placed for the next few years. Very brave of you to get up that early to view them.

I can completely understand why those who have not seen them will make the effort. I did the same nearly 40 years ago to get my 1st glimpse of Saturn in the early hours.

Those of us with a few years under our belts might prefer to wait until they are more favourably placed.

17 minutes ago, Captain Magenta said:

Tonight, for me, with my usual 15x56 Zeiss, impossible to separate in brightness from HD220167, so 7.1-7.2 by my estimation.

M

Had a quick look with my 12 inch dob earlier. Same for estimate for me.

It's still very much "with us" isn't it ?

1 hour ago, Louis D said:

Both of my Dobs use large Teflon pads riding on Ebony Star Formica (which is discontinued, I believe).  Any pebbly, glossy laminate will work well to provide just the right amount of sticktion.  Lazy susans accumulate crud over time, ruining the motion.

Agreed on both counts. If the teflon pads are correctly positioned, the motion against the formica-type surface can be very smooth and yet controlled. My 12 inch dob uses just that approach.

Sorry about the rather naff re-working of the Greek legend but I could not resist

I had my 12 inch dobsonian out for a couple of hours this evening, when darkness eventually fell.

I spent most of my observing time in Hercules re-visiting the globular clusters and planetary nebulae that I had observed with my 120mm refractor a few nights back.

The constellation was pretty high in the sky so the views of the brighter pair of globular clusters (M 92 and M 13) were pretty spectacular with the much larger aperture. At 338x magnification M 13 takes up around half the field of view and M 92 not much less. Stars resolved right into cores of both clusters.

A bonus that the larger aperture bought to M 13 was a view of the galaxy NGC 6207 around half a degree to the north east which lies 2,000 times further away from us than the grand globular cluster. At 122x magnification both could be seen in the same field of view with the cluster resembling a tight stellar swarm and the galaxy a small, softly glowing oval. Always a "stand out" view for me in Hercules 

The fainter and more distant globular NGC 6229, while not as impressive as it's illustrious neighbours, was easy to see and some faint star resolution was visible in the outer fringes of that one at 199x magnification.

Dropping back down to the area of sky beneath the "keystone" of Hercules, the small but quite bright planetary nebula NGC 6210 was quite easy to pick up and seemed to me to resemble a smaller version of the Cats Eye Nebula (NGC 6543) in Draco. A quick visit to Draco to have a peek at the Cats Eye confirmed this similarity in form if not in apparent size.

I've a busy day tomorrow so could not make this a long session. I did want to try and find something new (to me) in Hercules though and Stellarium suggested that the galaxy NGC 6166 might be possible and well positioned.

Well this distant galaxy was quite hard work to find tonight. Finding the correct spot in the sky was straightforward enough but actually seeing any trace of the galaxy, somewhat harder. Eventually I thought I was getting traces of a faint suspect glow in the right place at 94x magnification. Jumping up to 199x did not really help but a spot in between, at 122x (13mm eyepiece) confirmed the lower power glimpses with a little more conviction. It's surface brightness is around magnitude 12 I think but possibly a little less.

NGC 6166 is one of the more distant galaxies that I've observed - it's distance from us is given as around 490 million light years away. So that was a new object to end this session with 

Well ...... not quite. I could not resist a few minutes gazing at the Ring Nebula in Lyra, which was now well up in the sky and starting to look rather splendid. A future challenge will be to try and spot the central star in this famous planetary nebula, but not tonight. Just, relax, enjoy the views for a while and then time to pack up.

It looks in excellent shape !

While .965 inch fitting, those eyepieces are pretty good quality. The H.M (Huygenian-Mittenzwey) is a little tight on eye relief though.

I've owned a couple of Vixen 102's and the dew shield pushed on and off the objective cell with those, with felt pads to hold it in place. Not sure about the 80M though