Rob Sellent

Have you considered stopping down your Dob to around a 6" in such conditions? 😀 Aye, sadly not one scope is perfect at everything . Each type gives slightly different results and as you are aware, are better and worse in certain areas. Not knowing the budget, I don't think you'd be disappointed with the planetary and double star performance from something like a 7" Intes-Micro Mak-Newt, a SW 180MAK, SW 120mm APO, Tak FC100, Vixen FL102 😋 and so on. In my experience, that scope x 'blows away' scope y is a little over the top and more often just not the case. Each of these scopes will have its very own list of compromises, will give slightly different results and be better in some areas and worse in others. The other problem with lists like this is that unless you get the chance to try out the scopes yourself, at the end of the day, you'll have to follow your heart and just go for the design you think you'd like to own next. Each scope type will have its detractors and supporters based on a myriad of factors including but not limited to: local weather conditions, seeing etc, life style and family commitments, cool down, focal length, exit pupil from eyepieces, mounting requirements, portability, budget, bias towards one design over another and so on. If you could give some indication of some of these factors, perhaps it would hone and refine your enquiry a little better? Evidently, then, as it stands, there is no right answer but with your 16" Dob already in hand my own preference would be towards purchasing a decent APO 😁

I'm quite a fan of Barlows. I bought a simple x2 TeleVue some ten years ago and it's still in use. I wouldn't mind getting myself a x2 Powermate but just as I save the readies, along comes another expense and it gets pushed to the back of the queue again The main use the Barlow gets is with a 24mm to 8mm zoom. Rather than picking out individual eyepieces, I insert the Barlow and simply run through the focal lengths until I find what's perfect for the night's seeing conditions. If I feel the given object warrents a better view, I'll then use that focal length from an individual eyepiece. Again, I find a Barlow useful when out and about or traveling light. Rather than carrying a seperate case of eyepieces. I'll either just take out the zoom and Barlow or the Barlow and 2 eyepieces, a low power eyepiece and a second eyepiece about 1.5/1.4 the focal length of the low power. So if I head out with a 24mm for example, the other eyepiece will be around 15mm. That way I'll have a simple run of 24mm, 16mm/15mm , 12mm, 8mm/7.5mm. Suffice to say, this argument is not perfect and not ideal if viewing planets, for example, but for a light and cost effective approach it's a good way to head out.

That's amazing, Jack. I was out on the same evening observing exactly the same glob with my 4" 😀 Your drawing is very much exactly as I saw it I was wondering what mediums are you using for your sketches? It looks like chalk on black card but I imagine I'm mistaken.

Are they not in my signiature below? I have a Lunt 60mm for solar. A small TeleVue 76mm that is great just looking at 😋 and for travelling with. There's a Mak 127 collecting dust but that doesn't count. I don't think it deserves the name of telescope. Its optics are horrid and cannot compete on anything with the 76. I'm so embarrassed by it that I wouldn't even sell it on. There's also an Italian Mirrored (Ottiche Zen) 10" dob and until a few days ago, I also had a 12" but really couldn't discern a significant enough advantage over the 10", so I moved it on and have just purchased an old Vixen Fluorite 102 😊. The little 4" has blown me away. I've never seen Jupiter or Saturn look quite like that before and the star fields, clusters etc are gorgeous.

Very nice set up. And thans for getting back so swiftly

It's great to hear you're having some viewing pleasure with Saturn and Jupiter and allowing yourself some time with them With seeing's permission, I find they both reward the patient observer. Neil, just out of interest what scope/mount have you got?

Many, many years ago in a small town by the sea a little boy memorised a little mnemonic: My Very Early Morning Jam Sandwiches Usually Nauseate People. It's stuck in my mind ever since and all these years later I really wouldn't know what to do if I got rid of people

Nice report, Dave and glad to hear you're getting some nice views. I think Hyperions are good eyepieces and are only questioned in scopes faster than f6 or so. In your f12, I imagine they're the business 🙂

Good job, Neil I swear there's an esoteric art to using many finders! I mean, it's tricky enough locating an object without factoring in back to front and inverted views too them . Not to mention that some must surely have been designed by playful contortionists for a laugh

The 12" f/10 will be very good on objects like smallish galaxies, globulars and planetary nebulae, not to mention planets and double stars. Also worth considering that it isn't a dob, its forte isn't wide fields views but instead, a more compact scope relative to its aperture and the ability to give more magnification with the same eyepiece. The SCT will possibly take a little longer to cool, maybe also to set up and may need protection against dew. It might also be slightly less sharp and perhaps give a little less contrast than a dob of similar aperture. Needless to say, it is no slouch and the tracking mount will allow for comfortable nudge free observing at high magnification and for less than a $1,000 I think that's a good buy. It's tricky to know where one will go in this hobby. There are so many differing factors to take into account as one grows that it's almost impossible to say where one will end up. If you wanted an idea of what to expect visually, you can't go wrong checking out sketches by extremely patient observers. It might also be worth your time checking out posts here and on Cloudy Nights reviewing or contemplating 12" SCTs. For what's it worth, if I were to start all over again, I'd purchase a secondhand 10" dob along with 2 or 3 wide-ish field eyepieces, a Barlow, Cheshire collimator, pocket Sky Atlas and an ironing chair or drum stool. It's as easy to set up as a 4" frac, will cool down faster than an SCT, easier to collimate, have less problems with dew and will probably come in at around a grand. I feel this kind of set up ought to keep you busy for a good number of years and if astronomy isn't your thing, will be pretty easy to sell on again. Wish you all the luck

The 'smush smear' you saw could just boil down to the scopes having to push through more atmosphere on a night of less than good seeing. You were also using 0.8mm and 0.6mm exit pupil respectively and in my experience that kind of power often requires decent seeing. That's another possible reason to what you experienced . Regarding the star test, as Roland Christen of Astro-Physics put it, "Every Apo lens I have ever star tested, even ones that tested close to 1/20 wave P-V, shows different inside and outside patterns of interference. This is normal. By contrast, I have an 8" SCT that shows perfectly identical inside vs. outside diffraction patterns, but tests only 1/4 wave." I figure, then, that if you can get some decent views working around a general maximum of x1 mag per mm aperture, your scopes are doing just fine.

Finally arrived a Vixen FL102 😀 Made a little write up here.

A Vixen FL102 f 8.8 arrived safely yesterday morning. It was well packed, very secure but even then the couriers had managed to slightly damage the SW alu-case. The doublet was born more than twenty-five years ago. I guess sometime between 1985 and 1993. The objectives are an external lens in glass and an internal lens in fluorite. The anti-reflective treatment is a gorgeous emerald green and even today the FL102 is recognised as one of the finest 4" refractors ever manufactured. It was a warm, blue sky day, so I took the scope out to align the 6x30 straight through finder, to adjust the focuser and experiment with a little white light practice. Just as it's been for most of August there were no sunspots but today that hardly mattered. With the aid of a Lunt wedge and a Baader zoom the Sun surrendered a perfectly imaged 'blank' disc. As I sit writing this report the following morning I cannot express enough what a pleasant and relaxed experience yesterday's evening had been. Meandering across the night sky, from early evening Jupiter, up through the milky way and back again to Saturn. It was what an evening with a telescope should be. No pressure, no lists, no expectations. Stars were absolutely exquisite, clean and sharp, perfectly colour corrected. Deep forests of clusters sparkled like sunlight playing on a summer's river. Nebulae such as the Ring, the Veil and the galaxy Andromeda were gorgeous grey mist spectres of the night. And Saturn. I've never seen Saturn quite like that. Perfectly executed is the way I would describe it. The focuser is the scope’s only limiting factor. It’s good, very good. It’s fluid and smooth, it handles weight and there is no image shift. In any other scope it would be more than suffice but the 102s optics deserve more. I’ll see if it can be optimized without invasive modifications by tweaking the tension screws and if that fails I will try inserting a number of precision washers under the small plate of the shaft. Perhaps that will make focusing more snap-to before considering other more expensive options. Although no heavier than a smaller TeleVue 76mm and lighter than most 4" fracs with its longer focal length the AZ4 jitters at high magnification. There is a brief settlement period, perhaps no longer than a second or two but it annoys me and although optically fine, I cannot get along with the straight through finder. It puts me into some compromising positions that seems unfitting for anyone my age. All in all then, tonight felt very special, magical even. As I descended from the darkness I couldn’t help thinking that you don’t really need more than a good 4” refractor and stars to steer her by. The views from the FL102 were intoxicating. Such gorgeousness, such splendour. I have been humbled by the experience. As I packed away, a rising Orion alluringly tapped on my shoulder. Pleiades sang to the olive and lemon tree but I told myself they would be for another day. So it was off to bed with a smile I went. On a swiftly tilting planet I pulled the bed sheets tight and until forgetfulness arrived, sipped on that image of a thousand gleaming stars in my eye.

Thank you, Piero. That was very kind of you to get back and so swiftly to boot Your 3 scope set up is the business; one for going deep, another for those apo black-velvet-crispy-clean visuals and the ultimate grab n go. I think all three are keepers and see no reason for moving them on. I really like the look of the Ayo 2 and Berlebach. I'm on the hunt for something that will stop my 4" from jittering at high mags and your set up looks the business. Shame FLO are stocking, but then again, it'll give me time to save Thanks again and look forward to meeting you more on the boards

Maybe these might help, Ant link, link, link. If not exactly what you're looking for, they may at least get you in the ball park. I've got the Lunt 1.25" + ND3, and a Baader polariser and continuum filter and have had it for years. Performs excellently and just as well as its first day. I imagine visually, they'll be little in it between the more popular wedges on the market.

Wow - that's an amazing report, Matthew . Unbelievable experience and setting. Your photos are also rather cracking; those 2 day Moon/desert shots are gorgeous. Comepletely of tangent, but I was wondering, while out observing on the dunes etc, are there any nasty creepy-crawlies about or flying bugs that like to suck blood?

Looks like you had an amazing session, Lenscap Doubles really do provide a lot enjoyment: those color contrasts, those little gems on a background of gorgeous star fields and the challange of very tight doubles. I wonder with your own liking of doubles, you'll end up with a smaller frac to accompany your 8" if you haven't done already?

Nice to hear you spotted M13, Mark You've done a good job because finding and viewing DSOs is not easy. With a nod to sky glow and aperture, I think the other big factor which dictates what we are able to find and observe boils down to experience. With a little practice it's surprising how quickly things improve and how quickly we come to think how bright those Messiers are 😋. I guess it's around the 8" - 10" aperture that globulars really start to blossom. But whatever the aperture used there's a real pleasure viewing these types of DSOs. Just blows my mind to think that those photons from some 300,000 burning stars that found your eye tonight in some darkish pocket of London began their timeless voyage some 20,000 years ago while Earth was in an ice age. As a breed, we're still scratching around with our tools of bone and stone. There are no domestic animals; other than ourselves, we have no fury friends to speak to, no pet dogs, no pet cats! Metal work, the bow and arrow, agriculture, writing, not even the wheel, have been invented yet I think such things help put our human notions of history and its preoccupations into perspective. In a sense, something like M13 shows just how small we really are but in like manner just how much we have grown .

Lovely kit, Piero. Not sure if this is the right place to ask but I have 3 questions for you 😋 i) what's that lovely AZ mount of yours? ii) I imagine the tripod is a Berlebach but which one? (there are so many, I get lost) iii) do you have a gut feeling preference between your Tak and dob?

Perhaps like Charlotte, it's just their way of saying thank you 🙂

Good to hear you had a nice session, Greymouser I hope your aches are also on the mend; perhaps a good rest is in order A few years back I just didn't fancy doing any more night time observing. So I packed up my kit, put it all away and turned to painting and building tiny scale models. I knew the wonder and love of astronomy and stargazing was still there, but the time wasn't right. I needed to do something else. I figured that if I needed a week's break, I'd take a week, if I needed a year, well I'd take that too. What I want to say is that you're not alone in your despondency. I imagine many of us have felt the same 'motivational crisis' at one time or another but when it happens, don't beat yourself up about it. Sometimes we just need to walk away for a while, do something different and have time out. Sometimes, I guess, we just have to put what weve been up to behind us, before we can move on.

Aye, that's it I don't want to overload your initial enquiry, so will simply throw this out as a little more unnecessary information for you to take account of as you wish. On occassions, I think it's an error solely to pick eyepieces based strictly on magnification. Exit pupil is also an issue. Briefly, your average adult eye will dilate to about 6mm or 7mm in diameter. So, an exit pupil of say more than 6mm is passing more light to the eye than is necessary or useful. On the other hand, as exit pupil decreases, so does the light entering your eye. As exit pupil decreases to less than 1mm, viewing becomes evermore uncomfortable and observers start seeing weird floaters drifting in front of their eyes. By the time you get to 0.5mm and less, exit pupil is so small that for all but the most bionic of eyes the experience is quite uncomfortable. I mention all this because in a significant way, exit pupil is linked to magnification. You can work out your exit pupil with your scope by either: i) scope's aperture in mm / magnification or ii) eyepiece's focal length / telescope's focal ratio. Your SCT has an aperture of 235mm and its focal ratio is f10 (scope's focal length / scope's aperture). So your 40mm Plossl is giving you an exit pupil of around 4mm and a 10mm Plossl would give you a 1mm exit pupil. It follows that the smaller the exit pupil, greater is the magnification. Ultimately, your eye and local seeing conditions will set the boundaries but as a general rule of thumb, with the exception of double stars, it is only on the better nights of seeing will you be using more than 200x magnification. Starting from the low power end, exit pupils of less than 4mm to about 6mm are best kept for dark skies looking at large and faint objects, surfing star fields, the milky way and observing large clusters. 2mm to 4mm is good for everyday general viewing, they're great for most DSOs you will encounter, for the Moon and for the planets when seeing conditions are rough. A 2mm exit pupil is a general sweet spot for observing. 2mm and below is good for double stars, planets when seeing is good, the Moon, and for getting up close and examining brighter DSOs. From this, for general skies and general everyday viewing in your f10, I personally think it would be interesting to check out wide-field eyepieces at 3mm, 2mm and something around 1.5mm. You could get away with just the 3mm and 2mm if you also sought out a Barlow. After experimenting for a while with these ranges, you will then be in a better position to decide on where there might be gaps in magnification/exit pupil suiting your skies and viewing dispositions. Hope that helped a little 😀

Sketches are nice indications of what is possible to observe and how the object might appear with concentrated effort in the eyepiece. To get you started, here are a few artist: Erike Rix, Rony de Laet, Jeremy Perez, Micheal Vlasov. SGL has a really nice write up about what one can expect to see here and there's another description here. Needless to say, SGL and its members and moderators will also be able to help you with your enquiries. Hope that helps a little

Can't add anything to Stu's great post, but here is a useful finder map. If you still have trouble, below is a more detailed map. M71 and Albireo are also in the region and well worth a visit or two .

Aye, absolutely gorgeous image. Cracking work, Stuart