Photonic Nights

Hi Peter, I can't agree more fully about the contrasty image using two eyes. Despite the near-full moon , despite too all the light-pollution in my back garden, even the Double Cluster, washed out as it was, nonetheless showed a surprising degree of contrast through the binos last night. (So relaxing as well, using two eyes instead of one - all the difference between watching and squinting, it seems to me). Incidentally there were no chromatic issues with the Moon to report either. Not a trace. All in all then, I can't wait to see what transpires at my local dark-sky location. Just to make sure we're on the same page here, what I have is the 70/82mm equivalent of the 100mm centre mount shown in the link below, not the basic cheapo mount that came bundled with the scope. Personally I have absolutely no problems with it. It's smooth and predictable without being either over-tight or (horrors) sloppy. It tells me that the sweet spot in the adjustment lever has the right amount of forgive. It's worth point out too that the scope fully loaded is bang-on 4.5 kg. That and its length (39 cm) means it doesn't put the mount under too much stress. Financial considerations aside, I would like to have bought one of APM's bigger brothers; but as my sadly under-used 6" mak-newt makes clear, the trade-off between aperture and portability is always going to be a live issue for me. Hell, even my NP101 is starting to look a tad bloated! Hope this helps. Gray https://astromart.com/classifieds/astromart-classifieds/mounts-alt-az/show/apm-center-mount-for-100-mm-apm-sa-and-apo-binoculars

Yes, I too regard mounts to be of prime importance. No point having a great scope if the views are off the Richter scale! Having to do my astronomy out of town due to limited views and locally heavy light pollution, I own a (reasonably portable) Skytee 2 for my 4" refractor, a rock-steady tripod, certainly for my needs. It can even take without complaint my ES 6" Mak-Newt "Comet Hunter", though hoisting it to the zenith can at times be a bit of a fan dance (though well worth the effort). For the binos I have a CF Manfrotto 055, upon which sits a chunky APM Centre Mount. No instability issues to report there, that's for sure. That same tripod, together with a Scopetech Zero Mount (and a wonderful piece of kit that mount is too - I simply can't praise it enough) also does service for my trusty little ES "Essentials" 80mm triplet - a flight-friendly setup originally intended for a stargazing holiday down in La Palma, planned, would you believe, for summer 2020? Needless to say that adventure quickly hit the buffers, what with Covid and volcanic eruptions Steve, thanks for that chart. . . very interesting! By the way is there any difference in exit pupil size between standard telescopic viewing and looking through binoculars, say? Gray

Steve, thanks for your comments about the 10mm UFF eps. I await with interest your thoughts on them. By the way you don't think 10mm would be too much mag (40x) for my scope? Your TS 82mm rig does have some 27% more aperture than my 70mm one, after all. And the Morpheus 76* range does include a useful 12.5mm ep, but they're not cheap. On balance, I think it best to practice patience for now and use the time (weather permitting) to see what my still newish and largely untested binos is capable of delivering. . . even if it does mean sticking single higher power eps in it for occasional mono viewing. Talking of which, I made the elementary mistake of accidentally putting two different eps in the scope (ES 82* 8.8mm & Pan 68* 24mm). Even now the resulting eyestorm is hard to put into words and I don't think I'll ever see Orion's Belt in quite the same light again. Worse still it took a surprisingly long time before I saw the error of my ways. Live and learn. . .

Thanks for the instructive comments and advice. Yes, I'm also considering going for the APM UFF 10mm eps, certainly as a default option. They're reasonably priced and with their 60* AFOV they seem a safer bet than some of the ultra-wide ones. Peter(W), about these Morpheus eyepieces of yours: are they the 76* wide field ones, by chance? I mention this because I seem to recall reading somewhere that their compact build lends them highly suitable for binoviewers (and possibly binoscopes too?) I've never looked into a Morpheus as yet, but I'm impressed by what people say about them. I also like their long eye-relief. Thanks again. PS. I'm bound to say that gazing up at the Pleiades the other night, both through the UFF 18mms and the Pans, was quite an experience. . .

Hi Last autumn I purchased a binoscope, but have only now got round to using it. The initial experience has been, well. . . decidedly immersive, to put it mildly - all the more so since I'm so used to peering up at the cosmos through single eyepieces.* The scope itself (an APM 70mm SR binos) came with a pair of excellent 18mm eps. But I also have two Panoptic 24mm eps , which offering as they do a TFOV of four degrees at 17x are just the ticket for trawling through the heavens - the main reason for buying the scope in the first place. Nonetheless, I'd like to stretch things a bit in terms of magnification, and this is where my ignorance begins to make itself felt. Assuming that 35x~45x is a reasonable higher magnification range, given the scope's optics (also making due allowance for the UK's miserable climate) I had intended to repeat the Pan 24mm doubling act by purchasing a second ES 82 8.8mm ep to compliment the one l already own. But not having yet closed the deal, I've now had an attack of cold feet, insofar that I understand that ultra-wide field oculars like the ES 82s can be a problem with binoscopes. . . that one shouldn't go beyond the 60 to 65 degree mark for various optical reasons. I do respect such views, of course. All the same, I do wonder if this is true right across the board, and not just based on viewing preferences or personal "ophthalmological" issues. I would, therefore, like to know what the actual truth is, if such a thing exists in this regard. Thanks in advance. * I do also own a pair of 12x36 Cannon stabilsed binoculars, but regard their astro use almost as a different kind of viewing experience.

I've been trying for quite a while now to purchase a second Explore Scientific 8.8mm 82 degree ep for my new APM binoscope (I already own an ES 8.8mm). Unhappily, whether it's due to Brexit or Covid - or an amalgam of these two "conditions" - it seems that ES wide-field eyepieces in particular are exceedingly hard to come by here in the UK at present. With Televue waaay beyond my reach for now and in the foreseeable, I've hit upon Skywatcher's eyepieces instead, which do seem available here in the UK. The trouble is that I'm really out of my depth with Skywatcher's eps. I'm looking for mid-power ones that'll give me approx 45x~50x mag, which I guess is getting towards the upper 'panning' limit for this 70mm SD binoscope (given the fitful viewing conditions here in the UK). Someone did recommend a pair of 8mm Sky-Watcher SWA 70s. Can anyone back up this claim? Otherwise do upper-end SW eps have a good reputation? Regards

I stand corrected. Upon applying a magnifying glass to the hole, I realised it doesn't have a thread after all. . . duh? As has already been mentioned, I stick something in it (a screwdriver) to use as a lever to tighten or loosen the mount from my tripod - especially useful in the dark. Doing so without it can be a bit of a struggle. I've since measured the hole's diameter to be 6mm. Regarding the mount itself: it has shown itself during these last eighteen months to be far superior to my old Vixen Porta II mount . . and it does so in just about every department there is. I especially like the adaptable lightweight (yet rigid) design and the way it neatly packs up, perfect for travelling purposes. It's this "field" astronomer's best friend, in fact. Pricey, yes; but as is the case in other areas of astro hardware you really do get what you pay for in this instance. It's a quality piece of kit, in other words, and for me at least it represents Japanese ingenuity at its best. Five Stars.

To be absolutely clear, it's the one arrowed and highlighted by a circle in the image below. . .

My apologies for not having myself clear on this point. The threaded hole I was referring to (but failed to explain properly) is the smaller one located on the side of the circular base plate, i.e. that part of the mount which attaches to a given tripod, pier, whatever (but not the central 3/8" female threaded hole itself). It's highlighted in the manual, but unfortunately, the manual itself is in Japanese. Again, my apologies.

I can't find the right size bolt/fastener for the threaded hole on the mount's base (the part that attaches to the tripod). I've tried three different sized bolts so far, two US imperial and one metric, but no luck so far. Any ideas?

Having come into some extra cash, I'm thinking about purchasing a replacement travel scope for use next year. In particular I'm warming towards a TS Photoline 80mm FPL-53 f/6 triplet. Has anyone got any views about this scope? I am at present a purely visual observer, a factor which has to be borne in mind here. Thanks in advance.

Am I correct in saying you have the Skywatcher Evostar 72mm scope? If so, I have something around the same size (ES 'Essentials' 80mm triplet) and I'm constantly surprised just how good this little scope is. Also it's easily small enough to go as flight baggage, which was the main purchasing point. Then came Covid, which in my case meant saying adios to a first-time flight down to the Canary Islands. . . dammit