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lenscap

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About lenscap

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  1. I didn't know Tiger Tanks had stereo sound systems. Or do you plan to blast out 100watts of "The Ride of the Valkyries" to scare the hell out of the enemy model tanks?
  2. I noticed that ENS have one; http://ensoptical.co.uk/lx90-handset?search=autostar No connection. . . .
  3. Free bits from unfinished 1960's Newt self -build for collection from Dorset available on AB&S. Seems to include figured, but presumably uncoated 8" primary. https://www.astrobuysell.com/uk/propview.php?view=154340 No connection.
  4. Skysafari lists Delta2 Lyrae as a double, with magnitudes 4.28 & 11.20, But search stelledoppie.it and this is a summary of the result; a multiple with 11 components potentially visible in an amateur scope. This is my plot of the above data. With a 200p F/5 in Bortle 8 skies/ average seeing, I have seen the 6 brightest components to mag 10.30. The mag 11.20 should be doable but has eluded me so far. I think that for my setup, the dimmest 4 stars will need darker skies or better eyes If you are observing Delta2 Lyrae, how many components can you identify?
  5. If you use 400 step motors and a 2.5:1 belt drive ratio, 32 microsteps would give a (theoretical) precision of 0.3 arcsec on RA, which is about the same as the factory Synscan Goto's achieve. 3 or 4 deg/sec is a good slewing speed. 10 deg/sec would be more like a missile launcher than a scope mount, but if the motors have enough torque, why not.
  6. I used type T2.5 Timing Belts & Pulleys from; https://www.beltingonline.com/timing-pulleys-bars-272/t2-5-pulleys-279/?zenid=8fkphh3cp60497d3o16aq3vkv3 On the motors; 15 tooth pulleys, bored to 5mm (check your motor shaft dia), each with 2 off M3 grubscrew holes. On the worms; 30 tooth pulleys, standard 6mm bore, each with 2 off M3 grubscrew holes. This obviously gives a ratio of 2:1 which works fine. If I was starting again I would use 40 & 16 teeth for a ratio of 2.5:1 giving more precision for a few pennies extra. I used these motor mounting brackets; https://www.ebay.co.uk/itm/3D-Printer-Parts-42mm-L-Bracket-Mount-for-Nema17-Stepper-Motor-Alloy-Steel One of these brackets mounts the Dec motor as is. I had to make a second angle bracket to fit the RA Motor+bracket to the mount. I suggest you mount the motors before ordering the pulleys & belts so that you can check pulley clearances & accurately measure the distances between the relevant shafts & calculate the required belt lengths. There is no room for error with these tiny belts. Here is a belt-length calculator; https://bepltd.com/pages/how-to-calculate-belt-length These are the belts I used, 6mm wide; https://www.beltingonline.com/t2-5-synchroflex-timing-belts-2903?zenid=8fkphh3cp60497d3o16aq3vkv3 Hope this helps. Out of interest, how many steps/rev are your motors and what microstepping options does your EQDrive controller allow?
  7. Hi, and welcome back. A rough polar alignment is sufficient for visual observing & short-exposure snapshots. No need to see Polaris. Level the tripod, set the latitude bolts for your location. Point the N leg of the tripod North as best you can, for example, using a compass (google the local magnetic variation), app or local map. Select Siderial speed for stars or planets & this will keep the target in a low or medium-power eyepiece for hours. Here is a smart-phone holder. https://www.firstlightoptics.com/adapters/celestron-nexyz-3-axis-universal-smartphone-adapter.html Here is the manual for that scope; https://s3.amazonaws.com/celestron-site-support-files/support_files/AstroMaster-EQ_Telescope_Series_Manual_Web.pdf Good luck.
  8. Many of the stars listed as doubles in Skysafari, Stellarium & the like, are actually multiples. You can identify which have further components which may be within the reach of your scope using stelledoppie ( 200p F/5, EQ3-2, diy Onstep Goto, generic Plossls. 19th Sept, from 22.30 BST, Transparency - good, Seeing - average, rising 70% Moon) I observed several multiples in Lyra. HD 172131 This is a Quadruple (Mags 8.06, 10.63, 10.45, 12.81 Spacings 16",210",38") The first 3 were visible in a 10mm EP, the 4th eluded me. HD 178592 A Triple (Mags 8.57, 9.02, 10.84 Spacings 2.3", 99") The tight pair were split at x200 with the dimmer third just visible to the SE. HD 174638, Sheliak has no less than 8 components of which 6 are potentially visible in an amateur scope. I could see 4 ranging from Mags 3.63 to 10.62 with the dimmer 3 arranged in a near equilateral triangle and the bright primary close to bisecting one of the sides, giving the impression of a triangular pyramid. No surprise that the 13 & 14 Mag components were not seen . HD 175588, Delta2 Lyr Has 11 components which are part of the Stephenson 1 asterism, laid out in a ragged zigzag line over about 6 arc min. I could make out 6 of them up to Mag 10.3 at x100, and maybe the 11th Mag 7th by AV but it could be my imagination. STF 2474 which with STF 2470 makes up the well known Double Doubles Double is itself a triple. (Mags 6.78, 7.88, 11.42, Spas, 17", 264") The dim third was visible by AV. HD 179709 is a Quad (Mags 8, 9.1, 9.7, 11.47 Spaced at 10, 71, 74") with the 11.47 star visible by AV, the dimmest I have seen with this setup. STF 2430. Just a plain old double to finish. (Mags 8.94, 9.18 at 1.5") easily split at x200 and the closest pair I have yet split with this scope, helped , no doubt by the lack of glare due to the dim but near equal magnitudes. After a really enjoyable couple of hours on a lovely, mild night I now have a much better idea of the capabilities of this scope at my location. And with the possibility of moonless nights, better seeing & perhaps better dark adaptation there is plenty of room for improvement. Onward and upward!
  9. I assume that you have either the "Dual Axis Motors" or these "Enhanced Dual Axis Motors" sold under Skywatcher or several other brands; https://www.firstlightoptics.com/sky-watcher-mount-accessories/enhanced-dual-axis-dc-motor-drive-for-eq3-2.html These are OK for converting a manual EQ3-2 into a tracking mount but I would NOT recommend them as the basis of a GoTo system. It can be done and It has been done, but these motors are not capable of being driven fast enough to produce a satisfactory GoTo system. It would be very sluggish at best & I believe you would be disappointed with the result. I believe that EQDrive sell motor kits to go with their controller. I haven't used them myself but assume they would be fit for purpose, although maybe expensive. I built a diy GoTo system for my EQ3-2 based on the open source OnStep project using a pair of NEMA 17 stepper motors and belt drives. Since you already have the EQDrive controller you would not need the OnStep software or controller, but there is enough information in the Wiki to enable you to select motors & drives for yourself if you wish, which would be a lower cost solution. onstep@groups.io | Wiki There is another similar project, AstroEQ, which may be of interest. Tutorials & FAQ’s Food for thought?
  10. "It's Earth Jim, but not as we know it."
  11. Hi, and welcome to SGL. The EQ3-2 RA worm gear ratio is 130:1 and the DEC is 65:1. The other parameters will depend on which stepper motors you are using & what gear sets or pulleys & belts you intend to use to connect them to the worm shafts.
  12. No I haven't. But basic reading glasses can be bought very cheaply. What if you removed the "observing eye" lens from a pair and wore them at the eyepiece. Would this work? It would avoid having to scrunch up your non-observing eye to grip the monocle. Whichever approach you try, SGL rules require that you post a photo!
  13. Hi Kronos, have a read through the thread below which suggests that this is the correct lens arrangement;
  14. Look on the bright side. Weather forecasts are usually wrong!
  15. Hi mikeysweet, Have a look at this thread. Towards the end there are some suggested solutions;
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