John

Lambda Cygni is 1.5 arc seconds. Magnitudes of 4.7 and 6.2. Delta Cygni is wider at 2.8 arc seconds but the magnitudes are 2.9 and 6.2 so that can make it a bit tricky.

The separation of Zeta Herc is around 1.36 arc seconds isn't it ? I guess the limit for an 80mm aperture is around 1.5 arc seconds ? I reckon getting a "touching pair" would be a good result for an equal brightness pair. Zeta Herc is not an equal brightness pair so that adds to the challenge.

It's not all that close this time is it ? I thought the figure was around 5 million KM ?

Er, I've not actually used a Morpheus, but from the reports that others have made, they would be on my short list. I'd certainly like to try one someday.

As soon as there is something to observe until I'm tired or the weather intervenes. Anywhere between 15 minutes and several hours. I'm retired so I don't have to get up for work, which helps.

If I was starting a quality eyepiece set afresh the Morpheus would be high up my list I'm sure

Hi Jim, The Tele Vue's are better performers than the Celestron will be, whatever eyepieces they are used with. The Powermate's in particular are superb - probably some of the best image amplifiers around.

The foam in my cases is "pick and pluck" as well but I don't actually remove any. I've found that depressing sections of the foam around the eyepiece shape and then using the foam in the lid to hold the eyepieces in their depressions works fine. If I change an eyepiece (which I used to do rather often ) I could then pull the depression back up and make a new one that fitted the new arrival. My cases and foam have survived many changes of occupancy over the years and still look reasonably neat. Here are some earlier iterations of the same case and foam. These cover about a decade (earliest first):

With a 10 inch scope you will find magnifications between 150x - 250x work well on the moon and planets as long as the seeing conditions are reasonable. So eyepiece focal lengths in the range 8mm to 5mm will be useful. Using a good barlow is certainly one way to achieve that. Maybe John in Australia is referring to keeping the magnifications more modest at outreach events, which does make some sense because higher powers can be tricky to use for folks who have never observed with a scope.

The 10mm plus the 2.25x barlow in standard form would create a virtual 4.44mm eyepiece so quite a lot more magnification than a 6mm - 270x vs 200x. Seeing conditons and target would come into play more than optical differences I think. The barlow + 10mm combination would deliver more eye relief than the 6mm on it's own. Barlow lenses lengthen eye relief a little and the 10mm ortho already has longer eye relief than the 6mm of course. The Tele Vue 2x barlow is excellent but it's been a long time since I owned one. I would guess that the performance is similar in quality to the Baader barlow but the Tele Vue is better built. Nothing is ever 3x as good as anything that costs 3x less. The performance differences are incremental and get smaller as the quality / cost increases. The step between the stock eyepieces and the next step up (eg: £50 eyepieces) is the largest (even then not 3x whatever that means !) and then improvements get smaller from there. If you look at the eyepiece section you will see that people are still happy to spend a lot of money on these small gains though

BGO = Baader Genuine Ortho = out of production for some years now. Really superb quality if you can get hold of one. BCO = Baader Classic Ortho = in production at just under £50 each. Focal lengths available are 6mm, 10mm and 18mm. The 10 and 18mm are really good eyepieces and, IMHO still probably the best in terms of pure optical quality that you can get for £50. The 6mm is not quite as good as the 10mm and 18mm but still a comptant 6mm eyepiece. The Baader Classic Orthos work very well with the Baader Q-Turret 2.25x barlow lens which can also give 1.3x amplification if the optical element alone is used in the 1.25 inch barrels of the Orthos. All the above come with the standard ortho characteristics of eye relief that is around 80% of the focal length of the eyepiece. The Baader Classic Orthos have a slightly wider apparent field than the Baader Genuine Orthos (50 degrees vs 42 degrees) but the outer 5% or so of the Classic's field is what I call "framing field" and not quite as well corrected as the rest of the view. I believe this was a deliberated design decision by Baader. The eye lenses of the Baader Classic Orthos are slightly larger and easier to find in the dark than the Baader Genuine Orthos. The above includes the Baader Classic 32mm which is a plossl rather than an ortho design.

Good to hear that the Japanese have produced a competent 3.1 inch F/15 achromat

Disagreements are fine of course but lets keep the discussion friendly and respectful folks. Many thanks

Normal price is £15.00 I seem to recall.

Very interesting report Louis, thanks for compiling it and posting it here. I know how much thought and effort goes into these things One line in your report jumped out at me: "....It is not a good choice for studying objects as they drift across the FOV in undriven scopes....." I would have thought that the above would be exactly the sort of use that a 26mm "100" degree eyepiece should be aimed at. Whatever it's other strengths it seems a great shame if they cannot deliver in that sector. For all of that, your report was very comprehensive and an interesting read. Thanks again

One of the much renowned Circle-T abbe orthos. Proper 3+1 optical layout. Still very strong performers. I wish the more modern ortho designs had been of the "volcano top" style. Lifts that eye lens toward the eye so helping with the usual tightish ortho eye relief. You used to be able to get these for peanuts but I've noticed that the used prices (they are well out of production) have crept up to equal the likes of Tele Vue plossls now and rightly so. I used to have some of the University Optics branded versions - wish I still had them

+1 for this atlas. I've owned it for 4 years now and it has proved an invaluable companion to my deep sky exploring

Back in 2016, when I was on the hunt for a top end refractor, I would have happily gone for a nice Vixen FL102. It would have made a grrat companion to my Vixen ED102SS. None came up during my "window of patience" though so I went for the Tak FC100-DL instead. With the objectives of the same spec (all bar 2mm of aperture) and from the same optical company I would imagine that the 100DL and the FL102 would produce very, very similar performance. Maybe I'll get a chance to find out someday

I think we did meet up in a car park somewhere around there Russ I have done quite a few car park astro equipment exchanges over the years

I think John might have hit on the problem ?

When you say that you can't get the Skywatcher bars to fit in the clamp, in what way ? I assume that you have opened the clamp jaws and then tried to fit the DT bar into the deeper and narrower of the 2 recesses ? I have the ADM equivalent clamp and it fits the Skywatcher DT bars OK.

Russ, Do you remember back in 2009, you had an Aero ED30 on loan from FLO then passed it on to me along with your thoughts and I added some of my own to produce this review Was that really 11 years ago !!

I've read that those Lomo 102 triplets are superb My TMB/LZOS 130mm F/9.2 was assembled by APM and uses the Kruppax 50 tube as well. One of the benefits is that it seems never to dew up. Even if the outside of the tube is running with it, the objective stays clear. Do you find that with your Lomo 102 ?

I don't want to complicate things Barry but it does depend on the type of DSO. Some, such as globular clusters, are not adversely affected by light pollution as much and the additional aperture will make a real and noticeable difference there. Extended objects such as the large nebulae and face on galaxies are hit harder by light pollution so the difference there might be that you can actually see something rather than nothing with the larger aperture. I don't want to oversell benefits from aperture from a light polluted sight but I'm trying to get the balance right.

Unless the target object is quite bright (ie: magnitude 9 or brighter) I can't see it in any of my finders. I find fainter objects by "star hopping" using the finders and a good star map such as the Sky & Telescope Pocket Sky Atlas. The final finding of such targets is done at the eyepiece of the scope with a low power eyepiece. I really only use an RDF / illuminated reticule finder for getting the scope to the right part of the sky, to within a 4-6 degrees of my target. I've found this method works well for me