John

I found my F/9.2 130 refractor worked OK without an extension in the main. Once or twice I needed to turn the tripod but not often. Or were you thinking of a longer frac than that ?

I'm one of those people, unfortunately I still have the ES 17mm / 92 though and that is better in this respect for me as a non-glasses wearer. The optical quality and immersiveness of the ES 92's is very impressive. They are pretty much as good as my Ethos eyepieces. The best ES eyepieces that I have used. The downsides are that they are £400+ eyepieces currently and weigh a LOT ! With an F/4.7 scope though, coma is going to be an issue, unless @Size9Hex is planning on using a coma corrector ?

Collimation, as Mike says above, is not the issue here. You should see a decent image even if the scope is not collimated that well. What we need to know is what you DO see though the eyepiece when you point the scope at a bright star or the moon using a low power eyepiece, that is the eyepiece with the longest focal length, eg: 25mm or 20mm or similar rather than 10mm, 6mm etc. The most common issue with scopes not showing much at all is that the incorrect adapters are being used to hold the eyepiece so sharp focus is simply not achieved. This is why, again echoing what Mike says, a photo of your focuser with the eyepiece in place, as you have used it, will also help diagnose the problem. Of course these scopes can and do work extremely well otherwise they would not be so popular

The more you study a target, the more you will see. Returning to it over several sessions often starts to reveal more detail as well. There is no rush - the Universe is not going anywhere

The EQ3-2,EQ5, AZ4, Skytee II and HEQ5 use M10. The EQ6 uses M12. The AZ5 is 3/8th's I think. I believe those Meade tripods have a flat top. The above mounts need a recess of 60mm or 30mm (depending on the mount) in the tripod hub to fit into. Edit: The AZ5 can fit onto a flat tripod hub top I believe.

I've actually not tried an O-III on the Rosette Stu. I will next time out though ! It's a rather overlooked target for me to be honest - a recent thread on here put it back on my radar though

Another vote for the Powermate 2.5x here. I've owned a couple of them and the 2 inch 2x as well and they are totally invisible visually apart from the amplification you get. A close alternative is the Explore Scientific 2x Focal Extender which has similar properties and performance to the Powermates at quite a bit less cost. I currently use a Baader Q-Turret with my Tak FC100 DL and that works well combined with a 7.2-21.5 zoom but I don't use the barlow with prime eyepieces so I don't know how it does with those.

Seeing the difference between high performing eyepieces and very high performing eyepieces is usually down to getting a night of excellent seeing. So most often I've found that there are no significant differences. Then a really good night comes along and you start to notice a few subtle differences. And that's what you pay for Well, that's my experience anyway. The eyepiece is quite low down on Suiters "wobbly stack" of factors which impact sharpness and contrast.

Thanks. My scope last night was 102mm so not a big aperture. I find the Astronomik UHC does make generally a difference on emission nebulae. It is not usually an "in your face" difference such as an O-III filter makes on the Veil, but a subtle enhancement of the contrast and extension of parts of the nebula, in the case of M42, the curved arcs of nebulosity that extend away from the "fishes mouth" seem to lengthen and their shape is more distinctive. I have not had the Astronomik UHC all that long but so far it has made enough of a difference for me to want to keep it for use alongside my Lumicon O-III. Thats a better result than a few other UHC filters have had for me

A family social "zoom" call was scheduled for yesterday evening and of course it coincided with the first clear skies for a little while. Family has to come first though so I popped a scope (my Vixen ED102SS refractor) out to cool down early on and got on with the virtual socializing. By the time I was able to get outside, the moon had dipped behind our house and Orion was well across the sky as well. I could see that the transparency was not the best and it got worse as the evening progressed, unfortunately. So, as pushing for the more challenging DSO's was probably not going to prove productive I stuck mostly to binary stars, the brighter nebulae and clusters. Starting with Orion I went for the binaries Eta Orionis, Rigel, 32 Orionis, Sigma Orionis (4th star barely visible tonight), Trapezium A-D with E occasionally and F a "no-show". Finally in Orion, Alnitak was a nice bright split. Orion's brightest nebulae, M42 and M43 were clear and the much dimmer M78, the reflection nebula a couple of degrees above Alnitak was glowing softly. I put the 31mm Nagler eyepiece into the diagonal which gave me 21x and a whopping 3.8 degree true field of view. It was lovely seeing the whole of the "Sword of Orion" area in the same view and the Great Orion Nebula spreading it's "wings" amongst the pinpoint stars. The Astronomik UHC filter improved the contrast and extent of the nebulosity noticeably. Staying with the big Nagler / UHC filter combination I moved into Monoceros and the cluster NGC 2244 which lies at the heart of the Rosette Nebula. A lovely open cluster without the filter but with the filter I could just make out the vague smoky "doughnut" form of the Rosette Nebula surrounding the cluster. I was pleased to see these traces of the nebulosity given the less than ideal sky transparency. The extent of the Rosette Nebula is around 2 degrees so you need a good wide field view to take it in plus a UHC filter really helps. I switched eyepieces to something higher powered to have a look at the lovely triple star Beta Monocerotis. Moving up into Gemini, Castor split into two bight "headlights" and then, putting the Nagler 31 back in, to the big Messier 35 open cluster and the smaller, less distinct, and much more distant cluster NGC 2158. Crossing the constellation of the twins, the planetary nebula NGC 2392 (The Eskimo) could be seen as a tiny glowing patch of light close to another star in quite a rich star field at 21x. Its interesting to observe targets that you normally use high powers on, at much lower magnifications to see them within the context of their home patches of sky. Moving across to Cancer now, The low power, wide field was great to observe Messier 44, the Behive cluster with and then dropping down the constellation to pick up the fainter, delicate swathe of stars of the M67, AKA "The Golden Eye" cluster. Back to a high power eyepiece again to have a look at the triple star Tegmine (Zeta Cancri). It was clearly a 3 star system but the closer pair were touching giving a "peanut" or "snowman" appearance. The sky transparency was clearly starting to dip now so, moving across to Leo, I was pleased to pick up the faint glow of the 9th magnitude galaxy NGC 2903 near the lions "nose". The only galaxy I was able to see during this session. As the sky was turning more milky and the cold was starting to seep through my outer layers, I rounded off with the lovely golden pair of Algeiba (Gamma Leonis) and finally, as the fainter stars were fast disappearing, found my way to Iota Leonis below the lions belly. I used the Nagler 2-4mm zoom eyepiece to closely examine this interesting binary star. The stars are magnitude 4.1 and 6.7 respectively with a separation of around 2.1 degrees arc seconds (oops !) currently. They are just 79 light years away and the dimmer star is a G3 star, thought to be rather like our Sun. The brighter star is also a spectroscopic binary. These 3 stars are orbiting each other at a distance smaller than the scale of our solar system with the dimmer star orbiting the central pair every 186 years. The split between the A and B stars was seen at 160x and a little clearer at 221x. I was pleased to get this result considering the deteriorating conditions and the relatively small aperture of the scope. I nice point to decide to end the session and head back into the warmth I felt. I think the highlights of this session were Orions Sword / M42 at really low power with the UHC filter, seeing traces of the Rosette Nebula around NGC 2244, and getting a split on Iota Leonis. Observing sessions seem to have been few and far between over the past month or so. I was very glad to be able to enjoy a few hours at the eyepiece again

I bought one of those a few years ago. I used it with the Baader VIP barlow, as many do. I thought it might take over from my Pentax XW's and Tele Vue's and the performance was excellent but somehow I didn't take to it I think I found the business of working out the various combinations of T2 extensions plus the barlow element to get a wide range of magnifications started to annoy me. There was no mistaking the build and optical quality though and the AFoV was considerably wider than an ordinary zoom across the whole range. I'm glad I tried one though, having read so much about them from owners on here and elsewhere I think @Stu still has his ?

Great stuff Joe ! I'm glad you found M78 - I was observing it myself this evening with my Vixen 102 refractor.

No, the ED102SS is an F/6.5 ED doublet with an FPL-53 element although Vixen never confirmed that. The fluorite ones were F/8.8 and F/9.0. 3.8 degree true field with the "Terminagler" in the diagonal

Clear but a bit "milky" tonight so I'm giving my old Vixen ED102SS a short session on double stars. This scope is over 20 years old now. I've owned it for 14 of those ! Really versatile scope which can go from a 4 degree true field view to a sharp 200x plus. Hoping to take this setup to darkest Wales later this year

Thanks for posting on this mount. It is good to know about things that don't work so well. More useful in some ways than glowing reports

Have you some previous experience of DSO imaging ?

I think it is F/6. The aperture is 130mm and the focal length 780mm. Is this the scope ?: https://www.apm-telescopes.de/en/telescopes/astrograph-refractors/apm-lzos-telescope-apo-refractor-130-f-4.5-52mm-3.7-inch-focuser.html

That's with the Riccardi reducer I think David. The native focal ratio is F/6. LZOS make the 130 in F/9.2 or F/6 only. They are superb scopes but I don't image with my LZOS 130mm F/9.2 so I can't help with that.

I think CA is often over-emphasized as an optical issue. As long as the scope I'm using is showing as much CA as it's spec (aperture / focal ratio / glass type) suggests it should then I'm OK with it. What I do find a problem is Spherical Aberration (SA). SA does scrub off resolution and contrast and limits the scopes usefulness at higher magnifications. The TAL 100's were very good and low cost achromat refractors. This was mine from 1999 and it performed as well as the somewhat more expensive Vixen SP102 that I had owned previously:

The giant binoculars which are great for astronomy and not much use for wildlife - their close focus range is too far away and they generally can't be hand held. Personally I found 8x56 a good all round spec. I took a pair of these (Opticron's) on a trip to Australia a few years back and they proved good for wild life and had enough light grasp to be useful for astronomy as well. Very hand holdable as well The true field of those is around 5 degrees I think.

I've read a lot of reports from folks based in Florida on another forum who seem to have amazing seeing quite often and can usefully use very high magnifications with their scopes. So perhaps for seeing cold weather is not a pre-requisite ? Maybe it is more significant for transparency though ?

Viewing the Magellanic Clouds and the globular cluster 47 Tucanae with 8x56 binoculars was a superb experience. Hope to be able to repeat it when things get back to some sort of normality

All makes a lot of sense My experience would suggest to me that 90% of the performance of the high end scopes for 50% of the cost is realistic but such figures are subjective of course

The problem with a big dob, even if driven, is that shorter people need a ladder, which can be tricky in the dark. They tend to hang on to the scope, which does not work out well ! My society has an 18 inch newtonian but that is hardly used for outreach for similar reasons. The 12 inch SCT is much easier to share with people, the eyepiece being in a convenient position.

I was very, very lucky when I did this a couple of years back - I got the Sun I'm just getting around to sorting out the billing arrangements for it's use. Look out for something in the post shortly. Only a couple of quid per person per annum but 7.8 billion consumers so a nice little earner Direct Debit preferred