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jacksdad

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About jacksdad

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    Salisbury, UK

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  1. Received diagonal from @CraigT82 - much appreciated.
  2. That'd be brilliant, thanks. PM on the way.
  3. It's as aligned as possible without removing and reattaching it, and I have nothing suitable on hand right now - so rather than take it off and risk damage I'd rather it stay there for a few days until I dig out sticky stuff. It's not a bad view as it is to be fair, I'm just being deliberately picky - there's symmetrical aberrations right on the edge of field (ep might be slightly too wide angled for it) and it's just not as pinpoint sharp as the 150 PL or skymax 102...
  4. The focuser mod worked well, it just holds now (like it should really), which is nice. It's quite an engaging little thing - it's not the sharpest view ever, but with the 25mm SW ep it's just pleasant. So much so that I just stuck it on the floor by the back door and 45 minutes seemed to disappear Quite glad I got it, well worth the tenner (oh, I think I forgot to mention the 60 mile drive to pick it up )
  5. Well, I put some sticky back felt type stuff in the focuser tube which totally removed the play - I'll point it at the sky shortly and see how much difference it made. I reckon somewhere between 'some' and 'lots'. Job for later is to sort out the secondary mirror that isn't stuck to the cell thingy anywhere near central or straight... Oh, and possibly lop a bit off the focus tube because it doesn't need to be anywhere near that long.
  6. Oh definitely, I'm not knocking it at all - for the money (that they cost new) they're great - stuff in toy shops for the same or more just don't compare (but that's a different discussion). I've found nothing that makes it unusable by any means, but I have the capability to tweak it to make it better so why not? If they did this stuff in the factory it'd not be the price it is... In fact, the only bit that I can think of that's a real complaint is the pictures they put on the box - at least I knew they were downright lies before I got my grubby mitts on it
  7. Hopefully this is the correct section... The other night I got myself a Firstscope (76x300mm reflector) for a bit of fun - don't judge, it cost me a tenner Used, but as new condition, still boxed etc. It's also something my 6 year old daughter can play with without stressing over damage. So, first thing, get the mount adjusted so it moves smoothly. Azimuth was easy, just set the tension on the pivot bolt so it turns without wobble. Alt was a bit tricky - a handwheel type nut is supplied which I suppose works, but you can't nudge about. It either self tightens or loosens depending on how you move so there's constant faffing with undoing and doing up. An M10 nyloc sorted that, now the tension stays set and I can move it wherever and it just stays. So much easier. Onto the comically terrible focuser... It's all wibbly. The assembly doesn't move in relation to the ota, but the moving tube is really sloppy in the housing. At rest, about 3/4 extended: Then with light finger pressure: That's about 3mm of play. But worse: And then light pressure sideways (not pulling out or pushing in): That's almost fully in, and about 1mm just slop. It makes focusing, erm, interesting - think it's set and then the tube relaxes a mm or two from where you set it. There's no tension adjustment anywhere (the focus gear pin is butted up to the housing) so that's the next job to sort. Oh, and the supplied eyepieces (h20 and sr4) are quite quite poor - the skywatcher 10 and 25mm kit units are far superior. To be continued...
  8. As I understand it, the focal ratio doesn't affect magnification either... F/5 scope A - 1000mm focal length, 200mm aperture F/5 scope B - 500mm focal length, 100mm aperture. Put a 10mm ep in these and A will give you 100x magnification, B will yield 50x magnification. Get them both to the same magnification and A will be brighter. Anyway - good luck to the OP, may that scope bring joy! (Oh, and you can apparently stick that mount on a wedge to get EQ functionality ;))
  9. jacksdad

    Mount stability

    Something like that might not be a bad idea - I have some similar material so worth an experiment. I've got enough bits to cobble a focus motor and as that's the main source of nuisance vibration it's got to be worth a go. I think after that I'll be looking at powering the mount axis, not necessarily to track (although basic short term tracking should be relatively straightforward) but more for positioning.
  10. I'm after a diagonal, I'd prefer a 45° but a 90 would be acceptable. Not particularly bothered whether it's mirror or prism. Doesn't need to be anything special as long as it's not (too) terrible - very limited budget available though - a kit one that's been upgraded from would be fine. Anything kicking about?
  11. jacksdad

    Mount stability

    I honestly don't think that'll make any difference to the problem I'm experiencing. Compared to a standard aluminium tripod I could see a huge improvement, but 'mine' (my son's) isn't standard. The tripod itself is perfectly stable (what with having steel tubes and well tamped sand inside the aluminium sections). The vibrations and time to settle are in the mount itself (I can measure this) due to 'spring' - I reckon I could bolt it to a concrete pier and not see much/any difference, if anything it might actually be worse. I personally think damping is the answer now.
  12. jacksdad

    Mount stability

    There's a comment in that thread about loosening the top leg bolts which does highlight the different interpretations of 'stabilty'... With what I've done to the tripod and mount I have it stable - put it down and it stays there. There's very very little flex. But, it's still got some 'spring' to it. Slacken off the top bolts and the vibrations absolutely disappear, but it's not stable. More consideration required.
  13. I'll go completely against standard protocol here and say that EQ mounts are great for visual, even manual ones. An AZ mount or a dob might seem easier (and for some it is) but it's not always as straightforward as it seems. Depending on whether you've got a diagonal fitted (and what type) and the orientation of the eyepiece (especially with a reflector) up might be up, or it might be down and left might be left or it could be right... An EQ mount is basically an AZ mount that's halfway fallen over - you've got exactly the same 2 axis of motion to deal with, it's just that one of them is aligned with the earth's axis instead of being perpendicular to the ground. Get your head around that and it all falls into place. Once you've found something, tracking it is way easier with an EQ too, whether it's powered or manual. My (just) 9 year old son's scope is on an EQ and, while I do help with location sometimes and turning the ota to get the eyepiece comfy, he gets it and will happily track stuff by himself with no problems at all. Over the bank holiday weekend I got him up at about 2am for Jupiter and Saturn and he went between the two a bit before flipping round for moonrise... Setup needn't be a pain either, especially for visual. I've found that just getting Polaris roughly in the middle of the hole through the mount (where the polar scope would live) is plenty sufficient, just needing the occasional tweak on the dec to keep things in view if you're tracking for more than a few minutes. If I was in the same sort of position I'd honesty be looking at something like a 127 or 150 (or even a 102) mak or sct and a relatively cheap short refractor for wider views (even something like a celestron travelscope to start with, which is surprising with reasonable eyepieces) and an eq3 or equivalent mount (man enough for these scopes, even with both mounted).
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