John

Nice piece Chris I found the Explore Scientific Focal Extenders very, very nearly as good as the Tele Vue Powermates for observing use. If the budget allows though, a Powermate is a superb piece of kit

Some one on another forum had a similar question last year: https://www.cloudynights.com/topic/727206-how-old-is-this-gibraltar-mount-and-is-it-complete/

Fantastic report - I really enjoyed sharing your session though reading it Alas, the clear sky here last night came as I was turning in for the night as often seems to happen lately The coming week looks a bit more optimistic though !

I do that with my F/6.5 Vixen ED102SS. 3.8 degrees TFoV with the 31mm Nagler

I tend to mostly use my 1.25 inch eyepiece set with my refractors and keep the big ones for the dobsonian. All but one of my refractors can use 2 inch eyepieces but somehow, I don't often do that.

The manufacturers really ought to put some warning stickers on the scope: "Warning: do not immerse the optics of this scope in battery acid, roll over them with a road roller, or allow high velocity rifle bullets to be fired at them. If such treatment occurs we cannot guarantee that the performance of the objective will remain fully up to the original specification"

I'm expecting the lens elements of my Tak to melt, explode or disintegrate any day now, according to comments made in another thread on another forum Clearly I've taken a big risk unpacking the scope when it arrived and then using it regularly since then

Delta Cygni can be challenging if the seeing is mediocre and the aperture small. Quite a difference in brightness between the components makes the 2.8 arc second gap between them seem tougher to prize apart than would be the case for an evenly matched pair. Your Tak 102 is made for such challenges though, even if the conditions are a bit sub-par

I had my Vixen ED102SS fall off the mount onto a stone patio a few years ago. It made a horrible noise as it hit the floor but the damage was limited to the end of the dew shield and the focuser pinion, which got bent. No damage to the glass thank goodness and no effect on collimation either. Quite a tough scope ! Other than that, I've been fortunate not too experience damage to the optics in any of the refractors I've owned.

This USA based optical company have a good reputation I believe. The smallest aperture they list is an 8" but they might be prepared to do something bespoke for you: http://www.rfroyce.com/stand_mirrors.htm You could wind up investing a lot in upgrading a 4.5 inch newtonian to deliver slightly better performance than stock when, for less cost, you could purchase a larger aperture optical tube complete that would offer a somewhat larger performance upgrade.

I've managed it here (Bortle 5) a few times with my 12 inch dob. Very challenging though - probably the most challenging DSO I've managed to see.

The UHC and O-III type filters help improve the contrast of many nebulae. There is no filter that works for galaxies though. Dark skies and observing experience are the best way to get the best views of galaxies.

Do "the eyes" in The Owl Nebula count ? Not lakes but small ponds of darkness perhaps ?

No, my exchange was for the Meade 4000 SWA, Japan made but with rubber eye cups. Back then they were expensive eyepieces here so I thought that getting a couple of them in exchange for 3 TV plossls plus some cash was a decent deal. The 4000 SWA's were not well edge corrected though - I was really disappointed in them. Those plus some poor examples of Meade 4000 plossls of the same vintage (again the Japan made ones but with rubber eye cups) that I acquired put me off Meade eyepieces more or less for good I have to be honest and say that I have not "sought after" anything with the Meade branding for many years now. My only remaining Meade item is a Japanese 4000 series UHC type filter in the 1.25 inch fitting which does seem to work well enough for what it cost (not a lot !).

The 1st good quality 1.25 inch eyepieces that I bought were 3 of the "smooth side" TV plossls that I purchased new in a sale from Sherwoods in Birmingham. I went for the 7.4mm, 13mm and 21mm. I stupidly part-exchanged them at Telescope House for some new Meade SWA 4000 eyepieces (doh ! ) then realised, to late, that the TV plossls were somewhat better optical performers and spent a year or so finding them again on the used market. Lesson learned ! TH got the best of that deal !

Ohhhhh !!!!! (green with envy)

That's a very useful resource - I use it all the time when observing binary stars

One Russian optic manufacturer that you don't hear much about at the consumer optics end of things is Aries from the Ukraine. They are probably best known for the Chromacor optical corrector back in 2001 which was designed to correct the CA and SA in mid-focal ratio achromats (especially the 120mm and 150mm F/8 Synta made achromats) but also produce some very nice apochromat refractors including this 178mm F/8 fluorite doublet: The above scope was advertised a while back on the Astromart site "for a quick sale" at $14,990 ! Here is one of theirs aimed (presumably) at the professional market - a 14 inch F/12 triplet apochromat: A "snip" at 295,000 euros !

I enjoy listening to Daniel. His enthusiasm is infectious I suppose that I try and capture a little of that when I post my observing reports on here. I usually do them immediately after coming in from observing or even during a session sometimes, while the experience is still very fresh. They are probably a bit "gushy" at times because of that but that's often how I'm feeling when I'm typing them in !

I used to own an Intes MN61 150mm F/6 maksutov-newtonian (branded as Orion (USA). Superb scope, that was I often wish I still had it and I suspect that many other Intes / Intes Micro owners are hanging on to theirs.

If you are trying to do what I think you are trying to do with the adapter that has just arrived, I'm not sure it would work with the Startravel 102 even if you could get the short 2 inch push fit adapter firmly attached to the SCT adapter on the diagonal. To reach focus with the ST102 and a 2 inch diagonal you will need to be able to fully insert the 2 inch barrel into the scope focuser, so the end of the focuser is right up against the body of the diagonal. The SCT adapter will prevent you from doing this as far as I can see. There is a version of the Celestron 2 inch diagonal that comes with both an SCT and a 2 inch push fit adapter. With this diagonal you unscrew the SCT fitting from the diagonal body completely and screw on the 2 inch push fit barrel in it's place. The diagonal will then fully insert into 2 inch scope drawtubes, as it needs to. If you could just get hold of the 2 inch push fit barrel part, I reckon there is a fair chance that it could work the same way with your XLT diagonal. Here is the diagonal that I'm referring to: https://www.harrisontelescopes.co.uk/acatalog/celestron-2-diagonal.html?gclid=EAIaIQobChMIxvqUtcu78gIVweR3Ch3N-g5_EAQYBSABEgJsjfD_BwE

For quite a while the 4 inch refractor plus a dobsonian was my scope inventory as well. Then the refractors started to breed .......

The optical tube / mirrors date from 2005. I have the original optical tests / paperwork for it. It had 2 owners before me. On the side of the primary mirror is a further Orion optics sticker showing that it was re-aluminised in 2010 and Hi-Lux over coated. Back in 2005 I'm not sure that hi-lux coatings were applied as standard. The dobsonian mount was made for me by a member of SGL called Shane who is a bit of a wizard at woodcraft

If FLO can't help: https://www.teleskop-express.de/shop/product_info.php/language/en/info/p3443_TS-Replacement-Part-Worm-Gear-with-Shafts-for-Skywatcher-EQ5-and-similar-mounts.html

To be fair, I could not have built a base for my dob to the sort of quality that my SGL friend Shane did for me. His design and execution was excellent and has lasted really well