sorrimen

10” dobs tend to go around that price, and I would recommend them much more. EQ mounts and newts can put the eyepiece in some pretty awkward positions and they’re just less intuitive to use manually. I really can’t see any benefit to using a manual EQ over alt az apart from being able to track objects on one axis, but tracking on alt az isn’t particularly difficult once you’ve had a little practice. That’s all ignoring the fact that the scope is likely very undermounted anyway, so it’ll be a bit of a pain to say the least. The eyepieces are basically worthless, and the focuser and finder look awful so the good deal on the face of it is a bit misleading. @allworlds presents a good alternative with 6” or 8” dobs. A brand new 8” with a good quality focuser and accessories wont cost you much more than that scope, or just go with the new skywatcher 8” for a few less accessories. Go the used route on an 8” or 10” dob (10” starts to get big so consider your own fitness/strength and where you’ll set up and store it) and you can’t really wrong. Always a safe bet to ask here before buying anything so you’ve done yourself a great help!

Hm, I also have the 5mm with my 8” dob. At 240x, it does start to get a bit noisy but that’s at a 0.85mm exit pupil and it’s still useable. The 12mm barlowed at 200x is no issue at a 1mm pupil, but perhaps the 5mm is weak. I will do some investigating next time I’m out, but rest assured that your 7mm will be more than useable with whatever new scope you get and it’s not so much the magnification, rather the exit pupil that is causing you issues.

Helpful, we’ve determined perhaps 2 problems. First, was the 5mm some nondescript plossl? The tube-like view is from a narrow aFOV. Your naglers have a plentiful 82 degrees, whereas plossls will have somewhere around the 50 degree range. Not to mention the poor coatings etc. will provide much dimmer and less contrasty views. A quality 5mm will provide an entirely different experience to a cheap one. At 150x, you should be able to track objects by hand fairly easily, although it will be much easier with a full sized dob rather than a tabletop. More practice and a full sized dob will make 150x no issue. The ‘on fire’ effect is known as atmospheric seeing. If seeing conditions are bad, the atmosphere causes the incoming light to wobble about as it is slowed by very slightly different rates by the various particles that pass in front of it, as well as different temperatures and densities of air parcels. If you have fast high winds for example, you will have lots of different particles passing very quickly causing the view to wobble all over the place. If you have high temperature variations, you will get lots of mixing air slowing the light down by different rates. The closer to the horizon a target is, the more atmosphere you are looking through and naturally the more likely it is that seeing will be bad. Seeing will be more noticeable at higher magnifications, and the common atmospheric limits are ~200x (though that is entirely dependent on where you live). 150x should rarely be so bad as to provide worse detail than a lower mag, but you may have been unlucky on the days you tried it. Higher magnifications will by definition being dimmer as you’re spreading the light across a larger area, so the most ‘pleasing’ and beautiful views are generally found at low magnifications. For the most detail, you will generally need to climb magnifications though.

Bargain Nikon AE 10x50s. Brief daytime testing shows them to be good optically, and seriously comfortable.

You’re more than welcome, though I would still wait for what others have to say about my suggestions just in case there’s a good option I’ve missed. Regarding your eyepiece question. 150x in your scope is a 1mm exit pupil. In my experience, at 1mm you will maybe start to see some of the ‘noise’ you talk about but on planets it should be useable, and most people’s comfortable views are at the 0.7-8mm levels. For the same exit pupil on an 8” scope, you need 200x, and 250x on a 10”. 170x in an 8” will be brighter than 150x in your 150p. I suspect there may be other issues at hand. It may be that your eyesight is hindering you, or it may be that you need to practice using those smaller exit pupils to be able to see past the ‘noise’ or floaters. If it is your eyesight, 10” will be safe for most atmospheric average maximums. You will also want to ensure good collimation. If you’re out of collimation, you may have issues with illuminating your eyepieces or getting a good crisp image at high mags. I would imagine if you’re out enough, 1mm may be more uncomfortable than it should be.

Being able to compromise on GOTO is extremely helpful. I was under the impression that when you said adapt for AP you meant without changing mount or scope. Being open to buying a new mount is a game changer, although would be fairly expensive if you get a suitable visual scope. A C9.25, like the one used on the classifieds could be good, or even a C8 for less of an upgrade. In reality, if you’re willing to compromise on GOTO and would be open to buying a new mount for AP, I think your best bet is a manual 10” or 12” dob. You lose the ability to upgrade for AP, but the amount of money you save over a sufficiently mounted C9.25 or C8 means you have plenty left over if you ever wanted to get into AP. You could then buy a small frac and mount, with suitable cameras and guiding etc. which combined with the dob would come in at around the same price or even less than the AP suitable C9.25 (or C8?). Importantly, with the SCT focal length your 7mm and 11mm aren’t super useable compared to a newt. No need to faff around with EQ mounts for visual use (polar aligning, star alignment etc.), just plop the scope down and you’re ready to go. It means you get the best of both worlds, retain your eyepiece usage, can do both visual and AP at the same time, and to top it all off it’s likely to be cheaper! My line of thinking is C9.25 (used classified £1300) plus mount £2000-3000, let’s say £3000 total. New eyepieces needed increases cost, and targets for AP limited by focal length. Brand new 12” StellaLyra dob £849 (new and 12” is the most expensive combo, so used 10” could be as little as £300), WO Zenithstar 73 (£635) and HEQ5 (£1000). Total cost £2500, and that’s the most expensive iteration of the manual dob. Get to keep your eyepieces as useable, larger aperture and a whole different set up for AP for you to do both simultaneously if you wish. Neither include cameras but that’s for if you want to get into AP. If you don’t ever want to, with the second option you’ve lost nothing by having a worse performing £3000 visual scope. Interested what others think of this plan.

You’re asking a lot i.e. basically everything you can ask for in a scope. Portability, ease of set up, both visual and AP, significantly better than 6” of aperture, and to top it all off not too expensive 😆 I think your wisest option is to think about what you can compromise on. GOTO dobs are great and for a ‘significant’ upgrade over 6” you can get a 10” or 12” that is still relatively manageable in multiple trips, albeit getting heavy. That said, you will be rather limited photography-wise. As you understand, you will have field rotation limiting long exposures, and the tracking itself isn’t going to come close to guided set ups. There are people who do great work with quirky set ups, but these are generally people who already have a lot of skills and experience. I for one, without many skills, have done solar system imaging with an 8” dob with reasonable success, but I wouldn’t even dream of recommending this for someone wanting to get into solar system imaging unless they were very financially constrained. It’s possible, but you’ve said you want something ‘easily adapted’ to AP and I’d have to say that AP with a dob is simply the hardest form of AP there is. Unfortunately there is no such thing as a visual rig that is a significant step up above 6” (i.e. 10” or more as you specify) that can be adapted to AP if you suddenly decide you want to pursue it. Visual requires large aperture over everything else and arguably favours certain f/ratios (e.g. not too fast for aberrations, but not such a long focal length that limits any low mags). AP favours fast f/ratios and the best tracking you can manage, with aperture being as large as you can afford with good tracking. There are middle grounds that work e.g. a 150mm apo on a good mount, a large reflector on a good mount but these middle grounds are incredibly expensive and don’t fit your requirements anyway, either being too small an aperture or too heavy/unwieldy a set up. The issue is that whilst you can take photos with GOTO dobs and have good visual experiences with small scopes, neither are optimised for those purposes so it’s very difficult to recommend options without feeling you’re likely to be disappointed in one aspect or another with your very strict and expansive requirements. Note that you have also asked for improvements in detail and quality of views. Detail in DSOs is by far dominated by light pollution. Andromeda from my bortle 7 skies will look like a big grey smudge from 50mm of aperture right up to probably 250mm or more. Regarding planets, seeing is the dominant factor. 6” of aperture let’s you push well into most average places’ seeing atmospheric conditions, magnification-wise. Larger scopes will show you more detail to a certain extent, but they will be more affected by seeing and the magnification will be limited by the atmosphere unless you live somewhere with fantastic conditions. Improvements will be there but planetary detail is subtle so you have to be realistic! Hope I haven’t pooped on the party too much but I know if I was in your position I’d want someone to be upfront with whether my expectations were realistic. With some compromises you can be very satisfied, but I feel as though right now you’re on the path to be let down in one aspect or another. Best of luck!

A few things will be at play. First, at the high ‘magnifications’ (wrong word but you get the point) focus will be very sensitive. With my electronic focuser on the slowest setting, holding the button for anything more than a second will send me way out of focus. Second thing is seeing, as others have mentioned. It will make it very hard to get good focus with poor seeing. It’s not so much about getting a crisp view, rather locating the midpoint between the two out of focus ranges. At that point you’re in focus, even if it’s still jumping about and blurring from seeing. Another thing is focus travel. It doesn’t sound like this applies to your situation, as you’re finding a blurry midpoint. If it were to apply, a barlow normally fixes things. Final thing is collimation. A camera will naturally be a bit more sensitive to collimation issues. Chances are this isn’t a big issue as you had good views visually, but if you’re out of collimation enough things will never appear crisp in focus.

That’s probably the most beautiful set up I’ve ever seen!

Certainly feeling like it 😁 Did the same again tonight. Probably about 30 people for the moon, and finally managed to show 5 or so people saturn and jupiter. Simply one of the best parts of the hobby. Also got incredible views of both saturn and jupiter. Small white storms visible on jupiter with the spot and similar detail to images, saturn with a fairly clear cassini, but incredibly clear cloud banding and polar region. The ADC is pulling its weight now that I’ve figured it out for the newt, and my new baader zoom has got its value just from tonight alone.

Last evening quick 30 minute pavement session for outreach. Always a fun time, but makes me very jealous of those of you who can set up in your back garden 😁

He’s likely talking about optimum planetary sampling. 4*pixel size yields f/15 and a 2.5x barlow (though 4x should arguably be 5x). 2x barlow would be fairly significantly undersampling, though depending on whether his set up is tracked it may end up being favourable. Image scale is essentially irrelevant for planetary as you can scale it up in post, as well as using ROI, so focal ratio is the focus instead of focal length. Still, sound advice to just try out the barlow and camera first. If the set up is tracked, moving up to a 3x gets you to optimum sampling. If it’s untracked, it would be wise to stick with the 2x and change camera to smaller pixels (asi462 or something).

+1 on changing LD setting. Put me off Winjupos until I realised that was the culprit of my funky edges!

Starguiders are some of the, if not the best value for money items <£100. Seriously can’t think of something better, apart from maybe a pair of gloves? Very very good optical quality for £30-35 used is fantastic. I think there is a 5mm going in the classifieds or on Astrobuysell, or at least there was one very recently.

Artificial intelligence, what an interesting point! Assuming a singularity (or approaching) type AI, it has all the knowledge but only has so because of human input, so is it intelligent or just an example of human intelligence? Intelligence is also so often conflated/related to something’s ability to manipulate its environment. An AI with bundles of knowledge and information but no means to do anything with it. Does it, with that infinite knowledge, understand its own existence? Just like with the slime mold; we don’t deem it more intelligent for figuring out an easier route with more precision than any human because it’s not thinking, so would we deem a knowledgable AI intelligent if it’s just following its own form of ‘reflexes’? I’m approaching verbal diarrhoea at this point; problem with telescope-like times but no clear skies to distract me 😴😆 For the record @saac, I’m only messing about suggesting humans to not be more intelligent 😁 the mechanisms for slime molds, bees etc. are all understood and aren’t reflections of intelligence, or in the very least don’t come close to human intelligence. An interesting thought experiment nonetheless.

As much as it’s a funny remark, it’s actually an interesting topic 😁 Take the Japan metro slime mould phenomena for example. Or watching orangutang(s?) perform memory tests without hesitation. Perhaps our brains are so full and complex, or maybe we’re the dummies 😉

I feel you there. My recent image attempts have been god awful…

Great, thanks for the reassurance all! Going to pull the trigger.

A few targets tonight. Namely a very low down saturn nebula and by far my best views of jupiter so far (despite a moderate jet stream and low pressure).

That’s my thinking right now. In the very least should be able to get my money back, but hopefully someone has used them to say whether it’s worth it.

Hi all Opportunity to grab these for £80. Good condition of course. On the face of it, looks like a great deal but can’t find a whole lot of info on used prices. Thoughts? Cheers Ross

Think the most conventional method is to stack (and process?) each video and derogate in winjupos. Problem with this in your case is that you could/should probably be recording slightly longer videos so that each stack has a sufficient number of frames. You could combine two or three consecutive videos in PIPP and produce 2 or 3 stacks instead. I’m not sure how much winjupos can tolerate, but damian peach goes for ~45 minutes of data per image so you can certainly do 3 or 4, 3 minute videos next time. Stack, sharpen, derotate, sharpen a bit more. Note that you could, aperture dependent, probably just combine all 6 and see what you get. Compare to one of the 3 minute combinations and see if you notice rotation blur.

+1 for the dew shield. Not sure about your observing site but it pays its worth in gold if you have any stray light (including moon of course). Yet to use it on a very dewy night but when that happens your finder and eyepieces are gone long before the secondary.

Not Ian, but have found the shorty to perform very well. No visible degradation at all with Starguiders (compared 12mm to barlowed 25mm). Will try and get a couple comparison images for you if you’d like. Downside to it is that whilst the barlow element screws off, it’s not threaded for eyepieces and can’t be used as a 1.6x.

Similar experience over here! Had to sacrifice a nights sleep to get clear skies from 1am onwards, but only one session other than that (which got ended early). Guess we should see the positive that it makes those nights so much sweeter. Imagine trying to motivate yourself to get out night after night when you know 300 nights a year are 8/10 seeing+. Actually that doesn’t sound so bad….