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Stephenstargazer

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Everything posted by Stephenstargazer

  1. All this talk of risers reminds me of one of the advantages of equatorial mounts, but I wont go there on this Thread! If you do need a riser then you should consider a heavier duty tripod (much discussed earlier!!) not just for the extra weight but also the the height added. This raises the mass of mount and scope well above the tripod intersect which increases tendency to vibrate. A really good riser design was the Vixen one shown, a one piece aluminium casting locating with QD spigots each end. Sadly I dont think there has ever been an EQ6 sized one. This is 210mm long and weighs 1.8kg. An economic low volume version for AZ100 could have CNC end plates welded into a cut tube to save cost of a casting mould.
  2. There might be some confusion here between 'stability' (resistance to tipping) and 'damping' (resistance to vibration). Some materials damp vibration better than others eg wood. But the 'stiffness' (resistance to elastic movement) of the tripod depends on both the components and joints. I think all the tripods mentioned above are well designed in that respect. But if you want 'rigidity' (least possible movement) then a monolithic pier is the solution. (On the basis of structural engineering, not trying to deny others experience)
  3. Only that with AZ 100 the counterweight is primarily to stop the risk of tripod tipping, rather than to reduce the load on the bearings. Until of course you get really big scopes....
  4. The beauty of the AZ100 is that it does not come encumbered with a tripod. Can see from above that the freedom to chose the tripod that suits individual use and scopes is well worthwhile. If you think you will need a riser then a pillar type tripod makes sense. I am very happy with a UNI28 for Tak FC100, but keep the weight down by not needing heavy clamp plates or counterweights. My panhandle never clashes because it is tilted up 45 deg courtesy of 2 holes from Derek. Just another personal choice.
  5. A very cheap (free) source of a 7Ah battery is the sealed lead acid type that are used for house alarms. They often get re[placed in a service but still have loads of life left. Also a 'dodgy' car starter battery will last for ages when only used for 3 or 4 amps. Big fan of orange boxes!
  6. The enigma is that tracking means motor drives which will bypass the nearperfect manual slow motions. To drive or not to drive, that is the question!
  7. Still find stock in fishing shops. They come with charger and bag too so worth a look.
  8. After looking at Tracer (for lamping) I came across the Ridge Monkey Vault (for carp fishing!!). Chose it for the connections and very pleased with build quality. 12v high current, 2x USB A, 1XUSB C. Small light and delivers what it claims. 13AH version sufficient for my mount all night.
  9. As the current AZ100 needs only to have encoders fitted, rather than motors and motorboards as on a go-to mount, it will be pretty resilient on a pier. The mount materials and stainless steel fixtures are durable. However for any mount kept outside the critical item is the durability of the cover and some measure to prevent condensation inside. Views differ on whether to provide heat, a dessicant, ventilation or a combination of these !
  10. and we don't need one because we will only ever be able to 'see' the observable universe at any time from around here. It's all a matter of time.....
  11. As most will know S&T is alive and well in the hands of AAS. They regularly advertise the jumbo version of the Atlas, available from their shop. I have both sizes and find the jumbo easier to read in the dark and it has a hard cover. Perhaps the pocket was out of print? I recall it was being revised?? I subscribe to the magazine from the UK and it arrives mostly on time. https://www.shopatsky.com/maps-globes/sky-atlases
  12. Do people realise that the mounting hole on the DSC shelf is offset? Take it off the ball joint and the shelf plate can be turned round to offset it right or left.
  13. @Trentend Balance point difficult with Cats but you can either fit a longer rail or put a small weight on the front of the rail, like 1kg on a clamp. Sometimes a dew shield is enough and that helps reduce stray light too.
  14. @Trentend you can always have the finder bracket on the underside and turn the finder round instead, can give some good positions which works for me with my VC 200. Nice to hear from another Denk user too - the power switch makes the binos very effective compared to e/p swapping and buying pairs. On the clamps: 365 Astronomy do a very economic and effective Vixen double clamp which fits the Rowan tappings (M8 35c/c). Good alternative for for lighter scope side. It has 2 independent brass clamps as opposed to the 2 screw/ 1 clamp designs.
  15. Could it also come from stacking? Check an individual frame and see what the ISS is like? I don't really believe earthshine given the miniscule transmission of a solar filter at ND 5. But that takes nothing away from a great photo! 2nd thought, what part of earthshine would be at H alpha wavelength? I just have a genuine interest in understanding what photos show, and what is artifact.
  16. Very likely, should have thought of that! Mind you with a solar filter that is still surprising. How about refraction?
  17. Any idea why the ISS is not just a black shadow, as in transit of Mercury, Venus ?
  18. Sad news. I am sure you will like the DF. Good strong focuser. If you want a bit more focal length in future the EX Q1.6 works well with it. Whereby hangs a tale (or tail!). When I first mounted my DF I bolted the tube clamp direct to the mount and that is a very safe fixing as the tube can only slip so far, even when loose for balancing. With the Q and binoviewer I needed more travel to get balance and changed to a dovetail bar and clamp. Clamp has 2 screws but I will be adding stop bolts on the bar NOW. The Tak (Vixen) bar has end plates so adding a bolt is easy, they should come like that! Next day: have added cap head stop bolts as picture. (not so easy! what look like c/s screws are plated brass with tops peened over or loctited? so drilled out and tapped for M5). Next step is to make the Tak tube clamp screw semi captive so it cant slip off.
  19. I am waiting for an 'unprecedented' Moon. Presume it will just pop up and not bother with the boring old lunar cycle. its being grumpy that keeps me cheerful ! However the antipodean branch of the family should have had a total eclipse on Wednesday. Awaiting report. That's worth a shout.
  20. Well except a good Fluorite APO! I am lucky to have both so it's a fair observation !! Back to the question, I deifinitely agree that an economic 150mm Maksutov of reasonable quality is hard to beat for the price and ease of mounting. That is what @Goldfinger proposed and I dont see that either that scope or its mount would trouble many backs. As long as he avoids carrying tripod, mount, scope and accessories in one go (which is never necessary, even if occasionally convenient). Likewise seated viewing is a 'no brainer' for comfort. As someone who started with a 140mm Maksutov (OMC) I think his choice should provide years of use and many observable objects from planets to DSOs until he develops a more specific interest. Meanwhile if he pines for wider views (the main Maksutov disadvantage) I suggest getting some binoculars, an asset that does not become redundant for any astronomer, ever.
  21. And the far side is quite different too. Given the timescale since the LGB, the orientation of the moon may well have changed. Vulcanicity has changed many features but is not uniform. Just two proposals but the answer is probably known by planetary scientists!
  22. The man who worked out why most lunar craters are circular, did so after noticing the same pattern with WW1 shell craters. Back then we did not have the wealth of detail of the moon that orbiters and digital cameras have provided. In fact without stereoscopic images deriving any elevation data is very crude, relying on shadow estimates. Aerial stereoscopic photography was developed in WW1 too. PS @wornish that was a very good question to pose. Easy to get carried away looking at 'stuff' and not spending the time to understand it.
  23. I have used skywatcher/clone 9x50 finders and did not like the rather small field of view and dim eyepiece for star hopping. In that respect the 6x30 raci works better! Antares make a 7x50 raci with a good eyepiece and widefield of view that gives a bright image. Expl Scientific seem to make something similar in straight but erect, not tried one. Vixen 7x50 (s/h?) also give a fine view but straight, inverted. Anything near the zenith is hard with a straight finder. Have sold my DOB but would chose the Antares with a Telrad. There are also 10x60 available but they are heavy to balance. Seems like finders are very much personal choice and never perfect!
  24. Rational? What's the fun in that! Sold three scopes, bought two...and a teensy mount and tripod...plus some matching accessories. Sold a few more bits of clutter, got a FLO voucher and some PP balance, now buying a Delite. More to the point my notebook has more observing entries in the past 12 months than any previous year, but you still have to do something when it is cloudy. SGL is a source of information, inspiration, entertainment and temptation. Should it also have a Sanity Clause?
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