John

9 hours ago, Paul73 said:

And there was me thinking that the ED120 was a big scope!!! 

What mount were you using?

Paul

The mount is a Giro Ercole. It is up to carrying the load but takes 3-4 seconds to settle when higher magnifications are used. I would say that it is getting marginal with the ED150 on board as is the Skytee II. Some people would find it acceptable but some would not.

Really the ED150 would benefit from an EQ6 mount or even a Losmandy GM11. This is the challenge when refractors get over 127mm / 5 inches in aperture - a truly suitable mount can easily exceed the cost  of the scope.

The ED150 (150 refractors in general actually) is a large instrument and often the additional costs of mounting them steadilly is a major factor in deciding if they are for you. My ED120 (also pictured) is a lot easier to mount steadily:

Generally low to medium powers so 30x or 90x. Some of the planetary nebulae are small so benefit from higher powers once you have found them.

UHC and O-III filters can make a big impact on nebulae observing so are well worth considering.

Here is a positive report on the scope from an SGL member:

https://stargazerslounge.com/topic/318766-a-sky-watcher-evostar-ed150-ds-pro-lands-in-yorkshire/

Despite the issues with the 2 examples that I was sent, I still feel that the Skywatcher ED150 has a great deal of potential. At some point I would like to try another example.

I met Sir Patrick twice and he autographed one of his books for me.

I've read many of his books and watched the "Sky at Night" programme since for over 30 years.

So, yes, he has been a big influence on me.

Incidently, the reason that he didn't make scopes himself was that he had no confidence at all in his DIY skills. As far as I'm aware, he had great admiration for those who could and did make their own instruments

11 hours ago, russ said:

Wow, i used to love the Astro Systems scopes. We visited Astro Systems in 1987 (i think). Was their place in Luton? Sure it was. But i decided to buy a complete Fullerscopes system instead. 

Yes it was Luton Russ. I never actually visited but I pored for ages over their brochures before making a decision. Those brochures also made me aware of the Vixen flourite refractors - and the fact that they were a long way out of my reach at that time financially

I've not managed to see a saturnian moon transit but I did observe the planet when the rings were edge on to us around 2009-10. I can't recall a point when the rings simply were not visible but I do recall their angle being so narrow that they looked rather like a sharp needle of light sticking out of either side of the planet.

I found this EAS article dating from 2009 on such transits:

http://www.esa.int/Our_Activities/Space_Science/Four_of_Saturn_s_moons_parade_by_their_parent/(print)

My understanding is that the "window" of time when these events can be viewed is short - just a few months and during that time there may only be a handfull of transits visible. Add to that Saturns position which might not be favourable during that time plus variable weather and I suspect actual observations by amateurs are rather rare.

I currently have 7 scopes but if I had to go to just one I would probably go for something like an 8 inch F/6 Orion Optics dob with their best optics in it. Over the course of the past decade I've owned a couple of 8 inch F6 dobs (one GSO and one Skywatcher) and found them very versatile and capable of delivering quality views of a very wide range of astro targets. They are portable and fit into a car easily. Under really dark skies they go pretty deep but are also capable of showing fine planetary detail and split tight double stars. With a 2 inch eyepiece I would be able to get a 2 degree true field without too much trouble so all but the largest objects would fit in.

I'd also invest in a quality and comfy observing chair as I'd need to sit at the eyepiece of such a scope rather than standing as I do with my current 12 inch F/5.3.

As I'm typing this I keep wondering if I ought to be saying a 10 inch F/6.3 dob instead but I'll stick with the 8 inch F/6 on the grounds of ease of storage, portability and fitting int the car easier I think.

Do you think it was the sling itself or the way that it was implemented that was causing the astig issues Piero ?

Either way, I'm glad you have got to the bottom of it.

Those were the days - dodgy adverts in the back of the Exchange & Mart. I think the section was called "Scientific Instruments" ?

I've still got a few BC&F catalogues - the earliest with the "models" sporting flares, aran sweaters, lab coats and butterfly collar shirts !

Our equivalent of the "Celestron Girls" I suppose ......

I use an Altair 250mm Vixen type DT bar bolted direct to my Tak clamp for my Tak FC100-DL. It seems solid and a good solution.

28 minutes ago, JeremyS said:

Was there any particular reason why the OTA wasn't from Fullerscopes, John?

I was lucky enough for my parents to buy me a used 6-inch Fullerscope Newtonian on a MkIII mount and pedestal. I saw an ad in Exchange & Mart and we went over to Horsham to pick it up. I think this was 1975-ish. It was a lovely scope. I wish I still had a photo of it.

Probably cost Jeremy. I was on a very tight budget back then and I think the Astro Systems OTA cost a bit less than a Fullerscopes. The AS had a David Hinds made primary and performed very well I seem to recall. I ordered the OTA first and had it on a self made dobsonian mount while I saved up for the EQ mount. The EQ's sold by AS back then were Vixen SP's which were great but over budget I'm afraid.

I had to really watch the pennies back then with a new mortgage !

Thanks - I enjoyed reading though the BC&F history

I was a regular visitor to 63 Farringdon Road from the mid 1980's for around a decade. Whenever I had to be in London for business I managed to find my way there, even if the business meeting was on the other side of town !

I bought a Fullerscopes Mk III mount from Dud himself and had some interesting phone calls with him as I gently chased it's production progress

Great memories

Here is that mount carrying an Astro Systems 6 inch F/6 newtonian - my first "proper" scope and one that I used to observe Halley's Comet in 1986:

56 minutes ago, niallk said:

Nice one! I think I'll pull the trigger at that price

Or this price ?:

http://www.opticstar.com/Run/Astronomy/Astro-Accessories-Telescopes-Opticstar.asp?p=0_10_5_1_8_330

2 hours ago, Paul73 said:

I’ve used the mk3 and 4 without issue.

Anyone else had issues with these?

Paul

I've owned Mk2 and a couple of Mk3's. While they were not perfect eyepieces, they fulfilled the Baader Zoom's reputation as excellent zoom eyepieces.

Personally I think the 7.2 - 21.5 that I now have is as good though. Not such a wide field across the focal lengths but optically pretty good.

With these really tight doubles, if possible, I try and wait until they are at their highest point in the sky when trying to split them. A little less atmosphere to peer though and further from the LP and other stuff that intrudes into the sky from my horizons.

2 hours ago, Piero said:

.... In a solid tube, the whole tube cools down, and the mirror is separated from the back environment by its cell only. In my telescope, the whole wood structure "wraps" the primary mirror considerably and wood is a bad conductor. In the 2 photo posted in my first thread, you can see that there is an open area at the bottom of the mirror box. My thought is that area helps the mirror cooling down, but the part of the mirror which is opposite to it will cool down more slowly. Hence, thermal differentials around the mirror surface. I read a fair amount of comments on CN by people having classic dobsonians and the problem seems very similar to mine. They solved thermal issues using fans, also left on through the whole session. It would make sense as fans would not only cool but flow away warm air trapped around the primary mirror.

There could be something in that, I agree.

The rear of my primary is very open due to the simple cell design so it cools evenly I guess:

2 minutes ago, Rob said:

Defo re spawn ETX

https://www.telescopehouse.com/bresser-messier-mcx-127-goto-telescope-az-eq.html?gclid=EAIaIQobChMIn42XrsXP4wIVAbTtCh1z_wRSEAQYAiABEgJ1__D_BwE

Looks good John!. Nice upgrade mod there.

This is a bit confusing though:

"Primary mirror diam. (mm): 125" (mm presumably)

The ETX 125 used an oversized primary as far as I know - 138mm is the figure that I've seen measured. That would tally with a working aperture of 125mm.

Probably just a sloppy spec from TH.

Very good split for a 6 inch F/6 newt. David Hinds knew how to make a good mirror though

Interesting reading this.

Your scope seems quite "particular" Piero. But maybe these are just teething issues ?.

When I think about how little care I take over collimation (above a quick tweak at the start of the session) and the rather basic primary cell with my 12" F/5.3, it's slightly embrassing 

I have a fan behind the primary but I never use it. No sling either - just the older OO 3-point cell.

When you say that you are seeing astimatism, do you mean an elongated airy disk / diffraction rings on one side or something else ?

That looks neat John.

Is the rear cover plastic or metal ?

11 hours ago, cletrac1922 said:

When out doing presentations with my club, primary schools, scout groups

I actually use 17mm UWA

Was out last night, and Jupiter was almost over head, clear skies

Was able to see bands, and moons around Jupiter

Saturn was not far behind Jupiter, with Scorpio splitting both planets

Rings were very clear, and able to see a couple of moons also around Saturn

John

17mm John ?

Were you using one of these ?:

https://www.astroshop.eu/eyepieces/skywatcher-eyepiece-swa-70d-17mm-1-25-2-/p,33494

24 minutes ago, Buzzard75 said:

My Lunt 80mm came with the Lunt zoom eyepiece. I asked the same question before I got it. The Lunt is actually quite good and I've been happy with it.

I have the feeling that the Lunt zoom is the same eyepiece that have been linked to above under different brandings. I have compared mine to a Lunt zoom and, apart from the branding, it looked and performed the same.

Lots of choice in this design, Skywatcher do one as well:

https://www.rothervalleyoptics.co.uk/ovl-hyperflex-7e1-72mm-215mm-high-performance-zoom-eyepiece-125.html

Look at the price on this one with Orion (USA) branding !:

https://www.astroshop.eu/eyepieces/orion-7-2mm-21-5mm-1-25-zoom-eyepiece/p,17113

51 minutes ago, johninderby said:

..The TS version of the Lunt zoom is on special right now at Telescope Express and a great buy. 

https://www.teleskop-express.de/shop/product_info.php/info/p4651_TS-Optics-Premium-Zoom-Eyepiece--7-2-mm-to-21-5-mm---1-25-.html

I have one of these which was a very good H-Alpha scope and pretty good at night as well. It certainly looks the same as the TS one:

http://www.opticstar.com/Run/Astronomy/Astro-Accessories-Telescopes-Opticstar.asp?p=0_10_5_1_8_330

I think the TS spec for the max field of view is more accurate than the Opticstar one though.

That is the Skywatcher global website. Those eyepieces have been in the Skywatcher range for years and are available (as are many eyepieces) under various other brandings too. The website of the UK importer of Skywatcher gear (OVL) does include the 58 degree UWA Planetary range:

http://www.opticalvision.co.uk/astronomical_accessories-eyepieces/skywatcher_planetary_eyepieces.html

The world of eyepieces can be very confusing because many designs are available under many brandings and sometimes at varying prices !