John

Generally, yes. There is not a ready supply of spare parts for scopes available during normal times, let alone how things are now with supply shortages etc. Accessories such as finder scopes, diagonals and eyepieces you can get quite easily, but spare parts can be really difficult.

Great image - I love observing these fascinating crater chains though some can prove a challenge to resolve with a smaller aperture

I've often found M33 hard work but on a decent night and with some time being spent on it, it does start to reward by showing some of it's form and extent. Additionally it's one of the very few galaxies where a DSO that is external to our galaxy can be spotted with reasonably modest apertures - NGC 604 is a massive HII star forming region within M33 and I've seen it with a 100mm aperture. With a bit more aperture other such features within M33 are attainable, apparently.

This scope has fired my imagination for many years - Sir Patrick Moore's 5 inch F/12 Cooke achromat: And I also dreamed of one of these - the Vixen FL102M which I often drooled over (metaphorically speaking) during visits to Telescope House in Farringdon Road, London: 5 years ago I was able to purchase instruments that were of similar form and quality in the shape of a Takahashi FC100-DL and a TMB/LZOS 130mm (5.1 inch) F/9.2 triplet: The above scopes seem to have satisfied my refractor dreams My remaining dream would be to own a really large (18-20 inch) quality dobsonian AND to have a property suitable to use it from. The scope I can afford, the property, probably not currently . This is the sort of scope I mean (the location looks nice too !): The largest aperture scope that it is practical for me to own and operate from home currently is my 12 inch dobsonian which acts as quite a capable alternative to the larger light bucket of my dreams: This thread is about aspirations and dreams of course so there are no "wrong" answers

One of the first telescopes I used was a Prinz Astral 60mm refractor. I borrowed it from a friend for a couple of months in the mid-1970's and observed Jupiter, which was well placed that year, over a period of a couple of months (from my bedroom window ). After I had saved up my paper round money for a while I was able to buy a 2nd hand Tasco 60mm (which I still have) complete in it's wooden trunk for the princely sum of £45.00 ! Having used my old Tasco recently with decent eyepieces and a lot more experience under my belt, I think the optics of these scopes were pretty good but the economies were generally on the eyepieces and mount that were supplied with them. They got a lot of us started in the hobby though and there is NOTHING that matches the first views of the moon, Saturn and Jupiter that you get, no matter how humble the scope is

I did a sketch of that effect many years ago with my 60mm refractor (bottom sketch):

That's the nice thing about using a decent quality zoom eyepiece for double star observing - instant variability of magnification to find the most pleasing view

I used 400x with my 130mm refractor on Iota Cassiopeia earlier this year:

Most deep sky objects are seen in shades of grey visually I've found. You may see very subtle tints of green in the Orion Nebula but at best very subtle. A few planetary nebulae have tints of blue or green but again it's subtle. Filters such as the UHC or O-III type enhance the contrast of nebulae but usually not the colours. The colours in deep sky objects are bought out by imaging techniques which our eyes can't match, unfortunately.

That is puzzling. They should work of course.

There should be two focusing knobs, one on each end of the pinion shaft. Getting the finder aligned with the view through the scope is critical to being able to find anything in the sky. The view though the 25mm eyepiece is only around 3 moons diameter across so it's easy to miss things, even at low power.

What are you trying to see through the scope ? The arrangement you are using with the focuser drawtube, the 1.25 inch adapter and the eyepiece looks correct to me. These scopes won't bring things that are in anyway close (ie: less than hundreds of metres away) to focus. They are designed to focus on astronomical targets / distances.

The separation of the E & F stars from A & C is around 4.5 arc seconds which is resolvable, in theory, by scopes from 50mm and upwards. What makes them a challenge is the brightness of A and C and also I think the nebulosity within which the group is embedded.

You can see the areas on the moon where the landings took place but no traces of the landings. The smallest feature that we can see with amateur scopes on the lunar surface is around 1km in size and that takes some doing !. The largest object that was left behind by the Apollo missions was the bottom half of the LM landers which are around 10 meters in diameter (including the legs) I believe.

Congratulations ! Universal Astronomics mounts have an excellent reputation. It's sad that they are no longer made. I had their smallest model, the Dwarfstar, for a while and found that worked really well considering it's tiny size and weight. Yours looks a mightily capable mount

I'm surrounded by trees and houses as well. I treat many targets as seasonal and look forward to when they can be seen from my back yard as the months progress. They come back year after year and it's nice seeing these "old friends" again as well as seeing them, and others, for the first time

Great report of some excellent sights through your 4 inch refractor 😀 It's fun to play around with the UHC and O-III filters to see what difference they make on various targets. Other good planetary nebulae are the "Cats Eye" NGC 6543 in Draco and the "Blue Snowball" NGC 7662 in Andromeda. The O-III filter might also give you a sight of "The Owl" nebula, M 97, in Ursa Major. Apologies if you know about these and have spotted them already !

I've managed to see E & F occasionally with my 100mm / 102mm refractors (needs very good conditions with those), quite often with my 120mm and 130mm refractors and they are pretty obvious all the time with my 12 inch dobsonian. Getting the magnification right seems important to getting these stars - I find around 150x -200x to usually be the optimum. F is harder then E because it is close to the brightest of the 4 main Trapezium stars.

This is a good place to start - First Light Optics. Sponsor of this forum and a top quality supplier in terms of expertise and service: https://www.firstlightoptics.com/

Great report Iain, I really enjoyed reading it Seems a long time since I've had a long session under a dark sky with a decent aperture scope. Must put that right soon !

That's brilliant ! I think we need a group test of competing counterweights Are kg counterweights better than lb ones for example

I have managed to see E & F Trapezium with a 100mm refractor when the conditions are very favourable. The 120mm shows them more routinely and apertures above that, provided the conditions are steady, show them quite easily, when you know where to look for them. With my 12 inch they are really very prominent. The E star shows itself more readily than F because F is close to the brightest of the main 4 stars. I've found that I needed to work out the "goldilocks" magnification to tease out the E & F stars. There is some flexibility in what works on a particular evening but often I find that 150x or so works pretty well whatever scope I'm using. Going back to the original question, yes, the Orion XT8 is certainly entirely capable of showing the Trapezium very nicely and the E & F stars should be attainable as your experience grows and under favorable conditions. Many years ago I did this sketch of Messier 42 using my old 60mm refractor at 45x magnification. That scope was capable of showing the 4 brightest Trapezium stars quite clearly:

I agree with @Stu that the close up Sky & Night image does not look like the Trapezium at all I was observing Messier 42 a few nights back with an 8 inch newtonian from a site with some light pollution and slightly unstable seeing and this sketch by Michel Vlasov is a reasonably accurate representation of the view that I had at around 50x magnification and shows the 4 brightest members (A, B, C and D) of the Trapezium group clearly. The E & F stars are much fainter and need both more magnification and better observing conditions to see:

I've given up and bought the scope in now. There were some stars still showing but the seeing was poor so even the easy doubles are not going to look as good as they can and DSO's will be either invisible or pale shadows of how they can and should look because of the limited transparency and fast moving cloud bands. There will be other nights !

And their eyepieces sometimes !