Rob Sellent

Paraphrasing Tyson: It's probably only people who don't ask questions who remain clueless and dumb. You ask on and you'll be the wisest amongst all I'm not sure if it helps but a useful aid is to make circles either on a transparent piece of plastic or from wire that correspond to the field of view of your main low and medium power eyepieces. Use these circles on your star atlas to help plot your field of view and to map out your star hops from the brighter stars. Other tools I've found really useful - but acknowledge they aren't for everyone - is a Telrad or Rigel Quickfinder etc to get in the neighourbhood, then use a RACI finder scope. Just orientate the star chart so it aligns with what is being seen through the finder and star hop from there. If I've grasped your question correctly, I also think Moonshane's Locating Objects in the Night Sky an invaluable aid.

I've read through your own concerns, enquiries and responses to the outstanding advice you've received and I can't help thinking that the best thing to do would be to go and check out some scopes yourself. If there was no stargazing at the local club you visited this week, don't be disheartened. Go back and back again and get a real feel for what might be best for you. Seriously, it's better to 'lose' a little time checking up on what you want, than putting money into something you're not sure about, that may not be suitable or hold your interest for long. Save your money until you learn more of what you want your scope and you to do. I really don't want this to come across as harsh . I don't want to disenhearten you. I just feel that you've expressed a number compromises (heavy light pollution, astro-photography, large aperture, light or decent size for getting lifts by others, suitable plane carry-on etc) that ought to be addressed before purchasing pricey astro-gear. For what's it worth, I've been in a very similar situation to yourself. I didn't drive, lived in cities and had a load of compromises to deal with. My first ever astro purchase was a relatively decent but cheap set of binos. They can go everywhere and you can learn an awful lot by them . After a good year or so, I bought myself a 4" achro and an AZ-mount (the whole thing weighed no more than about 10kg) that I carried around in a single canvas bag. The upshot to all this is that it might be better to hold on, start small, learn a little about the skies and what exactly you're after and if your interest remains it's never too late to go bigger and spend more .

On the case right now 😀

The Cliffs of Mon are one of the few dark sky parks in Europe, so I imagine getting to them would be something quite special. There's a general tourist information guide to the area, and I guess with a little phone call or email to one of these B&Bs might lead to some fruitful information

Great links, Stu and thank you for posting them up. The Moon maps are excellent and will really help with visual work. It's clear out tonight but its late now - had a busy house clean Sunday - so if clear tomorrow, I'm going to put these maps to some good use

That looks such a lovely looking place, Starry. I bet it reallly was quite magical to be up there. Were you able to do any observing with binos or a scope?

Seeing that you've just got your Mak 127 AZ-Gti, I'd take real advantage of that pleasure and put the scope through its paces for the next season or two. See how you get along with cooling and dew over the winter and spring, whether you like the viewing position, field of view etc as opposed to the dob and so on. That way, when it comes to next year, you'll be able to make a much more informed decision on what you fancy doing, psychologically speaking because of use, you won't have lost so much on the secondhand market and from your knowledge gained be able to help others when they run into similar dilemmas. Everyone wins . In the meantime, if you're not getting along with the Goto Dob, you can sell and get a 10" manual dob secondhand for a fraction of the price and put the extra cash remaining in your astro-kitty. Don't spend it! You may find that you love the Mak and see no reason to move it on. Certainly its a better planet and double star scope than the linked wide field achro. Or, come next Spring, you may want to try your hand with a frac. Personally, I prefer using ed/apo to achros. My reasoning being if I'm buying a frac I'm not doing so for its aperture but more for its glass. You can pick up something like a SW100ed which is an outstanding OTA with the cash remaining from your Goto Dob. It's a really nice position to be in. The darker months to put the scopes through their paces, a little extra astro-cash in the kitty and some new potential buys for next year and all the pleasurable research that entails if the fancy takes you 😀

I prefer using scopes that are quick and easy to set up, cool down reasonably fast, have quick alignment and generally where there's no faffing about. For these reasons, like John and Stu, I prefer more minimalistic solutions. Again, aperture helps but if a scope becomes a drag to setup, takes too long to cool down and align etc, then its probably not going to be used that much and overtime will be negleted. Certainly, aperture doesn't always rule and there are times when less is more. Another anecdotal insight is that I have few scopes and to be honest my 12" dob only takes a fraction longer to set up than my 3" frac, for example. There's also a 10" dob at home, until recently a 4" frac (finger's crossed another one is on its way as we speak) and a SW Mak 127. In terms of set up they're all pretty much alike. I carry the newts out in two parts, I carry the fracs and Mak in two parts. In terms of performance the little Mak is the worst. No doubt I have a lemon but in terms of cool down, contrast, crispness and sharpness of planets and double stars, the Mak can not compete with the smaller 3" or 4". In terms of light grasp it cannot compete with the 10" and 12". Even when given really long cool down times and kitted out with the paraphernalia of a heater and yoga mat the Mak is still marked at a disadvantage. With reflectors, I've practiced with an 8", 10", 12" and 14". In terms of general everyday usage, my own sweet spot is either the 10" or 12". The larger OTAs and rocker boxes are only a tad heavier than an 8", have better light grasp, similar cool down period (especially if equipped with a fan) but in no way get to that 'monster', heavy weight stage of the 14". In terms of wide-fields, contrast, crispness and sharpness, I prefer decent refractors over Maks or SCTs. Sure, this is all anecdotal and everyone's millage will differ, but if it were me running a similar dilemma as yourself, I'd sell the 10" GoTo and with those funds generated I'd get a manual dob of similar aperture and replace the Mak with a nice, secondhand 4" frac for those off-the-cuff moments when you just want to 'grab n go'.

Nice little read about seeing and transparency here

Gorgeous sketch, Ruud. Absoluetly outstanding detail which almost jumps from the screen. Skies this evening looked wonderful. Almost as if the Moon had its own moon what with Jupiter tagging along behind 🙂

I was viewing Jupiter this evening and wondered what might make a worth while check list. I've probably missed somethings important, but hopefully this will get you in the ball park: Cooling: aim you scope at one of the bright stars you see (Deneb, Altair or Vega, for example). Defocus the image a little until you see concentric rings in your eyepiece. If insect/bug like things are crawling around in the image, you've probably got thermal issues. It helps when working at high power to get rid of these bugs, so allow time for cooling. My general rule of thumb is about 5 to 10 minutes per inch. Collimation: if this defocused image in your f5 doesn't look a bit like an offset bullseye, your scope may need a little tweaking. I've read two excellent guides to doing this: Moonshane and Astrobaby. Set Up: try not to observe over roofs, concrete blocks, or roads, etc. Better to view over lawns, grass or water. Seeing: if the stars are twinkling, seeing is probably not good. If they are steady, seeing might be okay. The thing is there's no real guarantee of seeing just by looking at the sky. Seeing is an elusive sprite. There are moments when everything is good, other times when it's hard to see much at all and all this could be in the same five minutes. Magnification: simply put, seeing affects magnification. Unless your lower power view of Jupiter is steady and sharp, increasing magnification isn't going to help. Indeed, its not always necessary to throw magnification at Jupiter to get some pretty decent views. In my little 3" frac, I often observe Jupiter between 60x to 100x and don't feel I'm missing too much. Experience: even if cooling, collimation, set up and seeing are spot on, planetary details may still be missing that are more than obvious to other observers. The only solution to this problem is experience. Let us know how you get along. It'll be a pleasure to read about your own and your son's adventures 🙂

I find at shorter focal lengths Orthos tend to be a bit more comfortable. Plossls will yield a slighter greater FOV, whereas the Ortho yields slightly better eye relief. Alomg these lines, I figure it's one of the reasons Televue doesn't make a Plossl shorter than the 8mm.

I'm sure another night everything will work out fine. Uneventful evenings like this are just that and I'm almost certain you've gained a good deal of knowledge and experience from this evening, even if it doesn't seem like that at the moment. After you've rested some and the sky conditions improve, I'm sure the C6 will have a happy ending. It's a fine scope; light, short, decent aperture, easy to mount and travel with and when properly cooled and collimated ought to surrender some outstanding views. I look forward to reading about your next session 🙂

I think it's the business, Jo. Great to hear that your son and yourself are having such a good time. Look forward to seeing a shot of Saturn

Wow, you're on a role, Karl. Fantastic work. It's so difficult getting stars plotted right when viewing but you've done wonderfully. Also love the subtle hues you've made to the dimmer stars. Great stuff

100% cloud cover, so no luck this end either 😔

I personally think this is a gorgeous sketch, Karl. The colours and inherent brightness is very well done. I appreciate just how difficult it is to sketch at the eyepiece and you've done yourself proud. Look forward to seeing more of your work in the near future

When it comes to observing Jupiter and Saturn, I don't enjoy an exit pupil any lower than about 0.6mm. At this stage the image of the planets is already quite dim for me and floaters are drifting more often in front of detail. As such, 0.6mm is a working limit on these two gas giants. However, I've also found that 25x - 40x per inch of aperture is a decent general guide for maximum magnification for me when viewing Jupiter and Saturn. I know folk observe the two gas giants over this limit but not all my scopes can handle this and just as importantly floaters are becoming ever more apparent and the atmospheric conditions where I live generally don't support higher per inch magnifications. Along this lines, I've found that seeing - atmospheric turbulence - starts to raise its ugly head from about 100x and really starts to interfere with my observations from around 180x to 200x. Unless I have very steady skies I can rarely observe Jupiter and Saturn over these higher magnifications. Finally, I also need to take into account things like the scopes collimation, cooling, my own fatigue and so on. So, as you'll appreciate, when it comes to observing Jupiter and Saturn there's a little bit of compromising going on: a) the quality of my eyes b) the quality of my optics c) the quality of the seeing and d) the 3 Cs: quality of collimation, cooling and personal conditions. If we take these ideas and apply them to you 6" f5 reflector, I think we can come to some conservative estimates. 25x per inch represents an exit pupil of 1mm. In your own case, you'll get about 150x with a 5mm eyepiece. This 150x, 1mm exit pupil I'd set for the moment as a high power for your 6". This doesn't mean you can't go higher. Of course you can, but exit pupil will become tighter perhaps giving rise to floaters, it'll cause further dimming of the object and decent seeing conditions will be more limited as you push the magnification. I feel this is good news, for you already have a 10mm eyepiece and a x2 Barlow, so you really don't need to spend the money . So much depends on atmospheric conditions when it comes to magnification and planetary observation. Perfect conditions are rare, especially this season with Jupiter and Saturn being so low. Personally, then, I'd sit it out. I'd advise you to not spend your cash on a lower exit pupil eyepiece and instead limit yourself to this 150x for this season with Jupiter and Saturn and see where you are in terms of scope, experience and disposition next year. Other than that, it might be an idea to invest in a decent zoom and overtime you'll be able to work out what maginifications work with your scope, skies and eye and of course perhaps the most important factor, to just sit calmly with the planets, spend some time at the eyepiece with them and let the seeing, turbulence and your own dispositions make the features more then less then more observable. I also think its a good idea from time to ime to sketch what we are observing. I feel this also strengthens observing skills.

Lovely report, Nick. Nice to see you had a good clear night accompanied by a friendly hedgehog to boot 😀.

It's an early bird's watch. After 12 it's time to relax with a little DT, DownTime. Anyway, if packaged correctly the envelope should look something like this 😋:

Lovely report, Karl. Looks like you picked up on some gorgeous gems and as you say, just sailing the milky way is enough to humble the most arrogant of folk. Thanks for a great read

I've read Jim Al Khalili and John Gribben's books on the subject. Both are accessible, well written and very informative. Needless to say, after ploughing through these two my undertsanding is still in its usual super positional quantum state of befuddlement

Glad to hear your report., Plumb. Not wanting to overload you but for Jupiter you might find this site useful: https://shallowsky.com/jupiter/ and for Saturn: https://www.skyandtelescope.com/wp-content/plugins/observing-tools/saturn_moons/saturn.html Other than that, if you haven't already get yourself a nice map (pocket sky atlas is extremely useful) and may I suggest just drifting slowly from Sagittarius up on over and through Cygnus before bedtime. There are enough wonders to behold to fill a thousand sweet dreams 🙂

Thanks for this Rob. It's always a pleasure to read visual reports from smaller scopes. Often times time is limited and without too much hassle or breaking a back there is a wealth of wonder to see with a small aperture scope. The other night I was out with a 76mm frac and spent a calm hour just enjoying the GRS and Europa shadow transit. Sure, under my average sky conditions this scope isn't going to be busting open globulars or tweaking arms in far away galaxies but engaging with the cosmos with gear that actually encourages that engagement is - as you have demonstrated - what makes this hobby meaningful.

Aye, I imagine on windy nights the 8" f8 may be a little troublesome but on these stiller summer evenings it must be quite a joy. Thank you for the heads up about Pi Aquilae. I've noted the star down in my notebook and will certainly check it out the next clear evening I get. I have a small TV 3" frac for general dash out and grab a view and a larger SW 12" dob. To be honest, these days I'm using the 3" a whole lot more. I've fallen in love so much with this little gem - its robust build and quality optics - that I'm seriously contemplating getting a little larger 4" (something like a secondhand FL102 or FC100). Thanks again for the reply and the cracking photo.