John

You look very well organised there Simon My scopes, mounts and eyepieces all live in a corner of the dining room. I just lift the scope or scopes that I'm going to use out through the french windows and onto the patio where I observe from.

Magnification limits are theoretical assuming perfect optics and perfect seeing conditions. Real world conditions mean that somewhat lower magnificiations are much more useful. Much astronomical observing is actually done at low or medium magnifications.

If the eyepiece actually has that, 18mm is generous eye relief. Often the actual usable eye relief is rather less though. The eye cup design and eye lens recess can eat into the eye relief.

If the seeing conditions are not so good, globular cluster resolution suffers as well.

I have an RACI 9x50 Celestron finder but I don't notice that it is stopped down. It performs very similarly to my Skywatcher and Orion 9x50 RACI's. There is a light baffle fitted inside the tube just in front of where the diagonal attaches but that looks as if it would allow the full light cone from the objective through.

Congratulations on the 5mm XW John. Like @Timebandit I have owned one for many years and find it an extremely well made and high performing eyepiece. It is my favourite lunar eyepiece with my 12 inch dob I too have ended up with a "short set" of XW's

My 12 inch dob has the same Celestron RACI illuminated finder that you have alongside a Rigel Quikfinder. I've also owned a few Telrads and they are very good as well. The Baader Skysufer III is a competent single dot finder but having the defined field circular reticules that the Rigel and Telrad has is a great help with star hopping.

Looks like my earlier post DID apply to your focuser after all. You do need the 2 inch adapter because the focuser drawtube is a bit over 2 inches in diameter so you can't put the Baader adapter straight into it.

Another reason why cherry picking from ranges is better than going for the "complete set" I had the 12mm and the 17mm ES 92's for a while. The ergonomics and eye relief of the 12 just didn't work for me but the 17mm, after some practice, I am getting used to and I know like. The 12mm went to a new home and its still a superb eyepiece. Just not for me I've avoided the 14mm and 20mm XW's up to now because of the reported field curvature but it might be that they are absolute gems for me if I do try them one day Only one way to find out ......

So orthos might be better choices for you than wide fields with long eye relief and large curved optical elements ?

Hope this one does not disappoint.

It depends on how much optical length your current adapter has. If it is a low profile one that just uses a few mm then the Baader will mean that you need a bit more inward focuser travel to get an eyepiece to focus. If your current adapter is high profile then the opposite might apply.

Yes it is as long as we all realize that one persons take on something won't be in any way a definitive one, it';s just one "data point" as they say. That's one of the main reasons why I've stopped doing reviews now - I realised that what floats my boat is quite probably not going to do the same for others !

The more you observe these targets, the more detail you will see in the. I know this may sound a bit trite but it really is true. I see quite a lot of detail in Messier 13 with my 100mm - 130mm scopes but I have been observing for some years so I guess my eye has become trained to tease the detail out. As Stu says, with globular clusters adding magnification helps to see more detail and the seeing conditions will vary as well. But observing frequently and becoming familliar with objects is the way to see more detail in them. This applies to all classes of targets and particularly with the planets. Small apertures can deliver great views but you need practice and persistence to get these. Unless you have a really large aperture scope and observe under dark skies, visual astronomy is rarely a case of "quick wins". It has to be worked at.

Eyepieces are all about trade offs I think. To achieve something outstanding in one area, something else needs to be compromised a little. The trick is to learn what you as an individual prefer and then to research and trial to find what suits you and what does not. What one person feels is excellent for them will not always find favour with another person at all.

I've just remembered that you have upgraded the focuser on your 12 inch so much of the above won't apply now. Sorry about that

The key thing is the optical length of the Baader adapter vs the optical length of your current one Barry. If they are markedly different, there maybe some issues with eyepieces coming to focus. The Baader adapter has an optical length of 9.5mm. Your stock 1.25 inch adapter might be longer (possibly a lot longer) than that in which case, using the Baader adapter, you will need to rack your focuser out further to get an eyepiece to focus. The other thing to check is whether your focuser, without the 1.25" adapter in, is really 2 inches in aperture. Quite a few Skywatcher focusers use a slightly oversize aperture which is why the eyepiece adapters (both 2 inch and 1.25 inch) have that tapered flange fitting at the bottom end. It is possible in that case that the Baader adapter will not fit snugly into the focuser tube. Sorry about the complexity but Skywatcher do have the habit of using rather non-standard focuser fittings and adapters

That's the joy of the dobsonian design - more of your £'s go into the optics, which are what delivers the views of course.

Over the years I've found 6mm to be a really useful focal length in a wide variety of scopes and there is no BST Starguider in that length. I would much rather put the £47 towards a decent 6mm (eg: a WO SPL perhaps) than buy the 3.2mm (which would not get anywhere near as much use) to "finish the set off". Likewise I would prefer to have something like a 30 Vixen NPL over the rather ordinary 25mm BST Starguider which costs about the same ( I owned both of these recently so was able to compare them). But I do realize that some folks just have to have "the set" and I have been there myself with Tele Vue Plossls, Nagler T6's, Wide Fields and even the Ethos of which I've owned all the focal lengths at one point. Expensive habit, that was Anyway, this is veering rather off the topic of Steve's helpful 24-26mm eyepiece comparison. Apologies for that Steve

I can't recall the scope you have ? (sorry)

I believe you have a knob with your name on it as well ?

If you can add a 7mm for high power observing, those 4 focal lengths would give you a good range. Later you might also want to add a 32mm for lower power observing as well. 4-5 eyepieces of focal lengths at or around these focal lengths will give you a versatile set.

It does get dark here but not for very long. 2-3 hours of observing and the light starts to infuse the eastern sky. Over the last few nights I've been able to see the milky way faintly running through Cygnus somewhere between midnight and 1:00 am. Had some decent views of the Veil Nebula with 100mm - 130mm scopes, with the help of the O-III filter of course. Still, its only going to get better now we are past the solstice and observing the deep sky in shorts is quite nice

Or a mak-cassegrain - they are pretty good at double stars and planetary as well.

Neat - that was introduced after the early versions that I tried.