John

13 minutes ago, Neutrinosoup said:

Thanks for this idea, I quite like the longer adjustment handles I got with my Vixen Porta which make it easy to adjust while viewing , can you get similar on this sort of sturdier Alt-AZ?

There are a number of sturdier alt-azimuth mounts that have slow motion adjustment controls. The Skytee II and the Sightron to name two of those.

If you decided to go for a Tak FC100 F/7.4 (DF or DC, especially the latter) you might find that the Vixen Porta copes OK with the lighter tube. I used to use a Vixen 102mm F/6.5 on a Porta with some success and that weighs around 3.4kg.

12 minutes ago, RobertI said:

Do you already have a decent altaz mount or do you need to buy one? I‘m just wondering if it’s worth trying the FLT98 on a good altaz mount first to see how more useable the setup is, before splashing out on a new premium scope? 

That's just what I was going to suggest 👍

6 minutes ago, Franklin said:

You have a great collection of extremely fine refractors John and the DL must be something very special.

Thank you. I'm very fond of them all, even the old Skywatcher ED120 🙂

This could prove problematical if and when I want to downscale my equipment though 🙄

11 minutes ago, bosun21 said:

.... With the defects the price should be a chunk lower than an equivalent one without the scratches.

Agreed - a big chunk lower. 

20 minutes ago, Franklin said:

The Vixen ED102SS F6.5 was released in 1999 and production continued until 2004 which makes it quite a rare bird these days.

I have seen a couple of used ones for sale since I bought mine, but only a couple.

I've no idea how many were made in total. A couple of thousand I guess ? 🤔

Quite common though, compared with the (off-topic) TMB/APM/LZOS 130 F/9.2's and the Tak FC100-DL's which seem to have total production runs at the sub-200 units level 🙂

I use the FT micro pinion on my FC100-DL and the Baader Zeiss T2 prism or an AP Maxbright if I want a 2 inch diagonal.  I've not tried an MEF-3, More Blue or a Tak prism. They are probably very nice 🙂

For quite a long time I got on well with an 8 inch dobsonian and a 4 inch refractor so I'm sure that I could "make do" with those again 🙂

It's just getting there that would be the painful bit 😬

41 minutes ago, Franklin said:

The price is going down, AliExpress will deliver one to the UK for a grand total of £73.14 right now.

I've seen reviews comparing these favorably to some tasty eyepieces.

That's good news.

I've just parted with some nice abbe orthos because the Sv 3-8 zoom showed Saturn and Jupiter just as well with the benefits of zooming, more eye relief and a wider AFoV. Svbony have a good one here 👍 

I'm a huge Ed Ting fan. I have read his web site for over a decade now and watched quite a few of his videos. I've taken some of his recommendations on scopes and found them spot on.

I have watched a few others but Ed is unmatched IMHO.

I have one just like that. There should be hex screws in the 3 holes next to the 3 philips holes. They might be in those holes so don't panic !

The philips ones are the primary tilt adjusting ones and the hex screws are the locking ones. 

The other 3 smaller holes should be empty.

So just to reassure you, mine looks just the same as yours and collimates fine 🙂

The movement that I think might be required to centre the secondary in the focuser tube is along the optical axis of the primary. I have indicated with red arrows that direction of movement:

4 minutes ago, Zermelo said:

I've seen wildly varying prices on different sites. I'm assuming it will settle down with time.

I'm concerned that it might revert to a somewhat higher price in due course. If the eyepiece bore more prestigious branding I think it's price would be far higher. 

39 minutes ago, Spile said:

The prices for the 3-8mm zoom were much higher than that on the sites I looked at. The 7-21mm was much cheaper.

The 3-8 zoom compares very favourably in build quality, and surprisingly well in optical terms as well, with the Tele Vue high power zooms, which cost nearly 4x as much. I could well understand the Svbony 3-8 being priced at around £250 or even more considering it's quality, but it's not and, IMHO, rather a good buy 🙂

With the Explore Scientific secondary mirror support design I am unsure how you would adjust the position of the diagonal along the optical axis of the primary, which seems to be what is needed to centre it under the focuser 🤔

The tilt of the diagonal is clearly adjusted by the 3 screws pictured in the photo that @dweller25 has posted above. But how can you move the secondary mirror closer to or further away from the primary with that design ? (which I think is what is needed)

Edit: I can see that @Ricochet is having similar thoughts !

21 minutes ago, John said:

My scope is still out but undercover as well. You never know ......

 

It's just started to rain quite heavily 😒

25 minutes ago, Nik271 said:

Same here, it was clear an hour ago, now completely clouded over. The forecast says it will be clear after midnight, so I've set up the scope under a waterproof cover in case it indeed clears up (and I manage to wake up)

My scope is still out but undercover as well. You never know ......

My TMB/LZOS 130mm F/9.2 triplet has a similar feature but it is a 2 inch format extension. It's very solid even when extended to it's full length.

A number of the APM/TMB/LZOS refractors use such extensions.

I thought I would post my astro "workflow" this evening to help newcomers to the hobby 🙂

1. Look out door - notice clear sky with stars showing.

2. Put out tripod with mount attached.

3. Put out scope to cool for a few minutes.

4. Pop eyepiece in focuser and snap photo for SGL.

5. Post said photo on SGL:

https://stargazerslounge.com/topic/274300-show-us-your-set-up-in-action-at-night/?do=findComment&comment=4432599

6. Go back outside full of anticipation of lovely Saturnian views.

7. Notice that the sky has completely clouded over from the west 😒

8. Notice that further west cloud was solid, even thicker and heading my way.

9. Bring scope, tripod and mount back inside.

10. Reach for beer from fridge and type grumpy post on SGL.

Doh !!! - stupid hobby !!!! 🥴

A whole bunch of boxes need to get "ticked" for this one to be achieved visually.

Over the past 10 years I've had the right eyepieces, the right filters, enough aperture, enough experience (well, almost !), good star charts, good advice etc, etc and yet things only came together a couple of times over that period from my backyard. If I'd travelled more to really dark sites I could have improved on that though. But at least I've had a couple of glimpses of it 🙂

I'm no imager but I'm told that the Horsehead is relatively easy to image and is quite straightforward with an EAA setup.  

My ED120 on the Giro Ercole mount eyeing Saturn this evening. Simple setup. The Ercole is actually flat black rather than the dark blue that it seems to show as in the mobile phone camera 🙄

6 hours ago, The Lapwing said:

If I could have found one I would have bought it. As rare as hen’s teeth as far as I can tell, mind you getting hold of a TV102 wasn’t easy, I was actively searching for one for a few years before I found mine. I won’t be selling it. 

That's interesting because I was looking, in vain, for a TV Genesis or 101 when the Vixen came up for sale on here back in early summer 2007 🙄

54 minutes ago, CHRlS said:

I was thinking more than likely going down the milk carton washer route, well start off with that anyway as it's the cheapest! Do you know the thickness of the washer you added?

The thickness of a Sainsbury's 4 pint plastic milk carton 🙂

Last time I had an ST80 the lens retaining ring was at the front of the objective cell. It had a plastic rim around it and to get any grip on that, the dew shield had to be removed. I think that slid off the objective cell as I recall. The retaining ring could have been overlooked though because, unlike many others, it did not have any location slots or holes in it to take a tool. It just has a smooth top plastic rim. I've had a look at a Skywatcher Evostar 90 objective cell that I happen to have knocking around this evening and that uses a similar approach. 

This is not my ST80 but it is how it looked with the dew shield removed. The lens retaining ring is marked with red arrows:

33 minutes ago, Spile said:

Sorry I don’t understand. The BHZ and Barlow together costs around £300. The Svbony alone costs around £225 . What am I missing?

The Svbony zoom can be bought new for £120-£130 last time I checked. The BHZ barlow costs £114.00 plus P&P currently from FLO.

17 minutes ago, Bugdozer said:

So can we conclude that Wikipedia's assessment of it as a bit dimmer than mag 7 is probably very, very wrong? 

Magnitude figures for deep sky objects can, oddly, be little or no help in guaging how easy or difficult it will be to see an object through the eyepiece.

Surface brightness is often a lot dimmer than the integrated magnitude figures quoted in sources such as Wikipedia but it is this, plus a host of other factors, that determine the actual visibility at a given time.

The galaxies M33 and M101 are good examples of this.