Guest CodnorPaul Posted August 23, 2013 Share Posted August 23, 2013 Evening all I am not a big fan of the SE mount my C8 SCT is on (single fork arm one) - it wobbles a lot which can affect viewing, and I don't find the go to accuracy great (may be partly due to me granted), plus it makes a right racket when slewing. I only do visual and don't envisage going over to the dark side. I am considering my options - do I: 1) stick with the SE mount and hope to get more accuracy, live with the vibrations, and enjoy the easy set up (but keep annoying all of you during meets!) 2) put the SCT on a new/used HEQ5 pro 3) get the new Celestron AVX mount 4) save a bit more and get a NEQ6 - think this would be overkill for me, and it is a big lump to cart around Thanks Link to comment Share on other sites More sharing options...
Brantuk Posted August 23, 2013 Share Posted August 23, 2013 Those single arm forks cause loads of vibration problems once you get over 5 or 6 inches aperture. Just my opinion but if it were mine I would sell it and put the money with whatever savings towards a more stable rig. You can get the same ota brand new and pop it on a VX or HEQ5 or (if you wanted to do imaging) NEQ6 Pro. Or alternately get a whole different ota to suit your aspirations (maybe a 925 Sct or an 8" Newt). At least with one of those mounts you have a lot of flexibility adding other ota's eg a refractor. Another good option for visual would be something like a 10" dob. Link to comment Share on other sites More sharing options...
dawson Posted August 23, 2013 Share Posted August 23, 2013 The noise isn't an issue. If anyone really is hacked off by it at a meet they need to get a life. It's slughtly more noisey than a skywatcher mount, but i suspect on a decibel scale it wouldn't be much louder, it's just not as high pitched as skywatchers. I'm sure there are ways to improve goto accuracy (accurate levelling (maybe), starting facing north, using a reticule eye piece to centre your stars when aligning...). Vibrations when slewing or all the time? Can you put heavier duty legs on the tripod, can you get a dual speed focus knob? Would any of these help? An equatorial mount is heavier, and is hassle in other ways to set up, and i wonder if you are only interested in visual if an equatorial will overall make life better, or just theow different challenges at you. I like your set up. It is easy to set up, and easy to use. If i wasn't drawn towards imaging it would be what i'd want. Jd Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 Some interesting points and a unique way of putting it - thanks James. The vibrations are with a slight breeze, or a knock of the OTA or mount, and take a while to die down - I have cut short some sessions if the wind is too bad (and not talking blowing a gale). I don't believe you can replace the legs, and I cant fit a dual speed to the back of the OTA as I already hit the mount when looking at/too near zenith due to the 2" diagonal - Feathertouch do a replacement focuser though which I could use but I don't notice it too much when focusing so can put up with that. I am happy with the OTA, and not sure the Mrs would not kill me if I were to sell it all to replace, so maybe I will hold fire for a bit. When we next get to a meet maybe I will take more interest in watching someone set up an EQ mount so I can understand the implications a little more. Link to comment Share on other sites More sharing options...
dawson Posted August 24, 2013 Share Posted August 24, 2013 "Some interesting points and a unique way of putting it"... I do try If focus was an issue, and you don't have enough length to look really high (towards the zenith) have you thought about a microfocus knob (no dirty comments Felix): http://www.jmitelescopes.com/images/mrf_mounted.jpg If a very slight wind gives you vibrations (ditto Felix), as I used to get with my 127 Mak on the Synscan GOTO mount, then I agree, it's annoying. You are more than welcome to come anytime to West Bridgford and see my mount, and Leigh is just round the corner with an HEQ5, I'm sure we could show you them both in day light and show you how we set them up (which might not strictly be correct). There are plenty appearing on ABS in recent weeks. How does your C8 attach to your current mount? If a dovetail then going onto an EQ mount would be easy, if it's forked and screwed into the sides, you'd need some minor alteration there (I think). JD Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 Yes its dovetail so nice and easy. I have just been looking at the motofocus, and the feathertouch SCT replacement focuser knob (which I think may be better and also reduce mirror flop if I were to go to imaging at any point), and also the Celestron vibration pads. From reading reviews the general consensus is the tripod causes the vibration and not the mount so now got me thinking Link to comment Share on other sites More sharing options...
Brantuk Posted August 24, 2013 Share Posted August 24, 2013 For dual speed focusing you can get a "Feathertouch Microfocuser" from Starlight Instruments like this one: http://www.firstlightoptics.com/starlight-instruments-feathertouch/microfocuser-for-celestron-cpc-800-6se-c8edge-8se.html That would get round the mount clash when looking at the zenith and they're purpose made for your scope. But Sct's from 8" upwards are always steadier on dual forks or heavy duty EQ mounts. I suggested replacing the whole thing cos though the ota would sell (they're fabulous scopes), I doubt you'd find a buyer for just the mount alone. But you could certainly get a set of tube rings and a dovetail to fit the ota to another mount - very easily and for minimal outlay. Hth Link to comment Share on other sites More sharing options...
dawson Posted August 24, 2013 Share Posted August 24, 2013 Is this the current set up: https://www.astronomics.com/images/Product/large/12174.jpg There just looks to be lots of plastic, and while there may be no plastic-on-plastic connections between the OTA and the tripod legs, the palstic may be hiding some less sturdy metal joints. Looking at it, in a similar mindset to my old syncan GOTO mount, even changing the tripod legs only goes some way to reducing the vibrations, and anti vibration pads at the bottom of the tripod legs do very little in my experience. To get a much sturdier OTA, I think you need to look for a mount which resembles an HEQ5/NEQ6. I'd have a look at these mounts in the day light and see the difference from yours. As Kim says, rings and a phat Losmandy plate would probably add yet more stability, but I have no idea how easy it is to find rings for your scope, they just don't exist anymore for mine and if you seriously want a set you might need to get them made bespoke (not cheap). JD Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 That's the one James - new mount it probably is then Link to comment Share on other sites More sharing options...
dawson Posted August 24, 2013 Share Posted August 24, 2013 Don't just buy one on my say so, I don't want Mrs CodnorPaul bashing me round the heed! It might be worth looking on SGL and doing a big search, as others with your mount might have found ways to improve stability (anti-vibration) which sounds like the biggest hassle for you. Or they might all say they've given up with it and moved to a more sturdy mount. Either way, there will likely be more people with your kit to offer advice. Look forward to seeing you again soon anyway. You are ALWAYS welcome to come over. James Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 Thanks James - may well do to get my head round it more Link to comment Share on other sites More sharing options...
red dwalf Posted August 24, 2013 Share Posted August 24, 2013 I have my 8 " sct on a heq5 pro mount and the two work well together, plus the mount is usable with other scopes you may purchase in the future, I also replaced the standard focuser with the starlight feather touch one which is expensive but a nice upgrade. I would only exchange this scope for the new hd version. Second hand heq5 are available for about 500 pounds, but you should be able to sell the nexstar mount for 300 pounds plus. Link to comment Share on other sites More sharing options...
BAZ Posted August 24, 2013 Share Posted August 24, 2013 I would say the vibration is intrinsic to single arm mounts. As it is plastic, the weak point is where the arm meets the base, and upwards from this. Any movement induced by wind or an impact, will cause the arm to flex and as the plastic is not rigid enough, it will bounce back and forth from the elastic properties of the plastic. This would be evident in the movement being more side to side than vertical. The tripod is not the greatest, but it is adequate for that rig as a visual mount. I don't think that anti-vibration pads will make any difference at all, the vibration is coming from the top down, and not the base upwards, so the damping would only apply to vibrations induced from the ground. This can be of benefit to imaging rigs, where even footfall will cause problems, but you won't notice a thing with visual. If you intend to start imaging then maybe get a HEQ5, and work you way to a NEQ6, it will give you experience operating and cussing properly at a EQ mount, and save you a world of pain on the domestic front. However, if like the rest of us, then it's easier to say sorry than ask for permission and all the justification that entails. Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 Thanks Martyn - no intention to start imaging at the moment, purely visual. So decisions to be made I guess - stick with the mount as it is only visual, or upgrade and get more hassle but less wobble Link to comment Share on other sites More sharing options...
dawson Posted August 24, 2013 Share Posted August 24, 2013 Are there any sturdy non-equatorial mounts? You are not imaging so field rotation isn't an issue. James Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted August 24, 2013 Share Posted August 24, 2013 none with go-to that I can find, except your posh mount of course but I cant justify that for my needs Link to comment Share on other sites More sharing options...
dawson Posted August 24, 2013 Share Posted August 24, 2013 There was one of mine on ABS I saw. Probably not a good sign, lol JD Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted September 4, 2013 Share Posted September 4, 2013 Is there anything to look out for when buying a 2nd hand mount, or am I better off just going new? Link to comment Share on other sites More sharing options...
Sheila Posted September 4, 2013 Share Posted September 4, 2013 Is there anything to look out for when buying a 2nd hand mount, or am I better off just going new? to me if you can afford it go new..... if not try to buy from someone you know or who has a good reputation on ABS or SGL Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted September 4, 2013 Share Posted September 4, 2013 That's what I thought the outcome would be - thank you Link to comment Share on other sites More sharing options...
Guest Kheldar Posted September 4, 2013 Share Posted September 4, 2013 (edited) That's what I thought the outcome would be - thank you With one notable exception I've never had a problem buying second hand Astro gear is generally well looked after obv. Caveat Emptor and all that, run the mount up - listen for crunches, check it slews smoothly etc Edited September 4, 2013 by Kheldar Link to comment Share on other sites More sharing options...
Guest ollypenrice Posted October 7, 2013 Share Posted October 7, 2013 (edited) Personally I much prefer alt az to EQ for visual. The fork (as opposed to arm) mounts by Meade and Celestron, while not my cup of tea for imaging, are really relaxing for visual, with few contortions to perform and no flip to faff about with. What about the iOptron Tower mounts. Would they cope? I've never seen one. Olly Edited October 7, 2013 by ollypenrice Link to comment Share on other sites More sharing options...
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