John

This one is not going "quietly" is it ?

Interesting report ! If you are in the UK and can split Antares the scope is doing a fantastic job. I've only managed that once (just) with my 130mm triplet refractor. Great stuff

Great report Joe Wonderful mix of targets !

The illumination was excellent on Shiller tonight - a lovely balance of light and pitch black shadow.

Just added the tiny planetary nebula IC 4593 to the Hercules haul tonight. Sometimes known as the "White Eyed Pea Nebula", this one is magnitude 10.5 I think. Pleased to add these two planetary nebulae to the globular clusters, especially IC 4593 - it's just so small !

I've just had another look and done the comparison with HD220167. I agree with you Magnus - I'll revise my estimate to mag 7.2. Maybe the slight "kick" in brightness continues ?

I've just been observing NGC 6229 again, this time with my ED120 refractor. Quite nice although still not resolvable even at higher powers. I also picked up the small planetary nebula NGC 6210 in Hercules - a pale blue irregularly shaped spot of light easily overlooked as a star at low powers. Lots of nice things in Hercules

Viewed with my ED120 refractor at 37.5x this evening I'd estimate the brightness at around magnitude 7.5 or thereabouts.

No further questions.

Lunar for me 100% Gassendi is really well placed tonight. Schiller as well. I think the only good thing I've ever seen on Eurovision was when Lordi won the thing

You have been banging this drum on the CN forum as well: https://www.cloudynights.com/topic/770738-who-services-lzos-lenses-in-the-us/?p=11103126 Have you personally actually used a scope with a LZOS objective in it ? If you don't rate the glass they use, feel free not to purchase and use one. You might at least respect the fact that others do really enjoy using their LZOS lensed scopes though. Roger Vine for example: http://www.scopeviews.co.uk/WO123.htm http://www.scopeviews.co.uk/TMB175.htm http://www.scopeviews.co.uk/TMB_C8.htm And our own Matthew Hodgson: http://alpha-lyrae.co.uk/2018/06/03/apm-lzos-115-triplet-apo-refractor-review/ http://alpha-lyrae.co.uk/2014/01/01/the-apm-tmb-105-f6-2-triplet-apochromatic-refractor/ So why not get a LZOS lensed scope yourself, compare it with some worthy rivals, and post your report ?

I think it might be known by some as the "sword". Here is another link that applies names to regions of the nebula: https://skyandtelescope.org/observing/see-orion-nebula-3d12172014/

Might get a chance to view this again later if "Clear Outside" is to be believed.

The one scope type, other than a refractor, that I have owned that has truly given "refractor like" star images is the maksutov-newtonian. In my case it was a 150mm F/5.9 Intes (Moscow) mak-newtonian. They have tiny secondary obstructions and no secondary vanes. Excellent optical figure as well. Cool down is quite a bit longer than a refractor though plus they are heavier.

When I've done comparisons of refractors of comparable optical quality on challenging double stars, perhaps unsurprisingly, the results followed the optical theory. For example, with a 100mm the close pair of Tegmine (Zeta Cancri) with a separation of 1.1 arc seconds is almost, but not quite split. With 120mm, the split is tight but clear, as the optical theory predicts it should be. With a "perfect" optic (ie: strehl 1.0) I understand that 84% of the light goes into the airy disk and the remaining 16% to the diffraction rings. It is interesting to see these theories in practice

It's amazing how small apertures of decent optical quality can support such high magnifications and still deliver sharp images. When I stopped down my ED120 refractor down to 52mm F/17.3 I found that I could still use 200x-300x and get sharp and well resolved double star images although the image had dimmed with the small aperture: https://stargazerslounge.com/topic/377032-trying-to-split-izar-with-66mm/?do=findComment&comment=4085866

The open star clusters are probably the easiest deep sky targets to see with binoculars so things like the double cluster in Perseus (not a Messier object), M 35 in Gemini, M44 in Cancer, the clusters in Auriga etc, etc. Asterisms such as the "coathanger" in Vulpecula or "Eddies Coaster" in Cassiopeia are also nice binocular targets. Some more of these here: https://britastro.org/journal_item/22500 The brighter globular clusters appear as condensed fuzzy spots and there are a number worth seeking out. Most galaxies and nebulae are somewhat less distinctive. Many can actually be seen, or at least glimpsed, with 70mm and even 50mm aperture binoculars but they are often small and subtle and can be easily overlooked by the inexperienced observer.

No reason at all. It was not long ago that many DIY finders were based on half a pair of binoculars with a cross hair added to the eyepiece field stop. Getting a 90 degree prism to work with a binocular can be challenging though because the 90 degree prism or mirror diagonal eats up quite a bit of the focal length of the objective lens so the body needs to be shortened to allow focus to be reached. It has been done though:

It's likely that is a 9x50 finder. Many of them are 9x. It looks very similar to the 9x50 RACI ones that I use. I have a similar arrangement on my 12 inch dobsonian except that I use a Rigel Quikfinder instead of the Telrad. I've arranged the eyepiece of the finder so that I can quickly move from it to the eyepiece of the scope, which helps when using higher magnifications in the scope - the target has less time to drift off !

For what it's worth, my FC100-DL has that gold touch on the plate as well. That one is 6 years old now. I'm NOT a "takoholic" though, before anyone asks

I have met and chatted with Martin a few times face-to-face and electronically. He is a very helpful, knowledgeable and personable chap. I hope he and Ann have a long and happy retirement

Nice memories Stellarium shows this for the max on 10th June from here (sunspot is a guess !):

When we were at the SGL star party with the large partial eclipse (2015?) I had Stellarium running as I observed the eclipse and it mirrored what was on show really accurately. That was a lovely clear morning with an 80% plus eclipse and a drop in temperature as max coverage was reached Were you at that one Stu ?

It's worth re-visiting the original post that started this thread. The original poster asked 2 questions I think: Question 1: "But, I'm finding one thing I'd like to see is galaxies and other DSOs, which I've had quite limited success so far (for example I'm reasonably sure I could see M13 but it was barely a smudge). I'm uncertain what the limits of what I should expect to see through the ST102 are, but aperture seems to be king so I presume I'll need to go bigger. But how big? Will a 6" fast refractor improve things significantly, or do I need to put in another garden store and go for a 10" or 12" Dobson? I've shied away from reflectors so far for simplicity sake." Question 2: "The other question is what effect higher quality glass has (I am clueless) - is the main benefit for resolving more detail on planets for example and more aesthetically pleasing images, or is there an element of compensation for aperture with better light transmission?" Both entirely reasonable and quite different questions with different answers but I think they may have got conflated at times by some of the "this verses that" discussion ?

Nice ! There are other letters up there: