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orly_andico

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Everything posted by orly_andico

  1. I've used the "gym weights sandwiched between the existing weights" trick before. With a 3D printer, it's trivial to make a sleeve so that the gym weight doesn't wobble on the CW shaft (gym weights are normally 1" ID, but most CW shafts are 20mm or 18mm). I was hoping to DIY something less agricultural. I had heard some folks 3D print a shell and then put fishing weights and epoxy inside. But fishing weights aren't cheap either... maybe cement is the way to go.
  2. Segueing off the long thread on "value for money," I decided to look into the practicality of DIY'ing mount counterweights. Geoptik sells a 10kg counterweight for 94 EUR ex-VAT. https://www.geoptik.com/en/prodotto/counterweight-10-kg-3/ Now all of the online metal stores I can find will sell a 10kg rough-turned 303 stainless steel bar (76mm diameter, 280mm long) for.. around 160-200 GBP! Although this outfit "only" wants 105 GBP ex-VAT... https://www.1stchoicemetals.co.uk/product/3-76-2mm-4/ What gives? I know Astro-Physics counterweights are really made of stainless steel... same with Planewave and Bisque. I suppose these other brands are using painted mild steel?
  3. IMHO you are better off just buying a 3D printer. Once you have it, you will find all manner of things to make. I started out ordering 3D prints online as well, but the turn-around time is maddening and you get killed on shipping. I had an Ender 3 V2 and now an Ender 3 S1 Pro, both were relatively competent but the S1 Pro is far more competent at 300-ish EUR? beats the pants off a made-in-USA Lulzbot Mini ($1200+) that I used to own. If you want a bit higher on the scale, Bambu Labs and Prusa are the usual suspects. I'd still go with some variety of Ender 3 for astronomical DIY. They are cheap enough, the better printers are if you want to make a living out of it.
  4. My comment... is that the weight suspended on the end of a flexible cord may induce some resonance that may disrupt the guiding. My personal experience with east-heavy bias (albeit not on a G11) is that the RA RMS guiding was cut in half when east heavy (!!) so definitely worth looking into. But I didn't use such a system, I just moved the counterweights up on the CW shaft to make the system east heavy (obviously won't work after a meridian flip).
  5. That is my concern.. 0.965" to 1.25" adapters will add a significant amount of back-focus which may compromise the scope's ability to reach focus unless the primary is moved up in the tube. I had one of those 25mm MA's - came with my first "real" telescope, an ETX-60AT, 20 years ago. It's OK. Not great. The 9mm MA is much worse due to the small eyelens and tiny eye relief. I have not had the misfortune of using symmetrical Ramsdens... EDIT: the manual says "modified Achromatic" which I took to be the Meade MA's (those are Kellners) - but then says it is an H 25mm which is a Huygenian. Which is across the board terrible.
  6. An f/8 newtonian should be optically a good one. But those eyepieces are terrible (the 25mm MA may be OK/marginal - but not the others and definitely not the Ramsden). In any case you really want 2 eyepieces - one for wide field (a 32mm Plossl should be a good choice giving you 28X with a field of a bit less than 2 degrees); and also something in the 10mm range giving you 91X for planets. Unfortunately the existing eyepieces are 0.965" diameter - and so the focuser probably also is. You'd need to find 0.965" eyepieces or somehow adapt the focuser to take 1.25" eyepieces which are far more common. These old Meade keypads had an issue with the rubber keys where the keys would stop responding to key presses. You may want to see if all the keys still work. That handset appears to be the Autostar 494; if the keys don't work you can either buy a keypad refurb kit (basically carbon grindings in glue, that you would paint onto the keypad contacts) https://www.trainshop.co.uk/maintenance/19827-keypad-fix-permanently-repairs-all-rubber-keypad.html or buy another Autostar controller. A 495/497 which has more keys is around 50 quid and is much more user friendly than a 494. https://www.cloudynights.com/topic/843110-autostar-hand-controller-compatibility/
  7. I will add that the RT80C has a bowl, and to fit a 3/8” tripod screw to it, you have to screw in the provided adapter - which does not rest flush on the bowl, i.e. there is no way to physically keep it level. You have to level everything by eye or with a bubble level, tighten the adapter, and hope it remains level. Quite an annoyance, I ended up 3D-printing a sleeve to keep the adapter level. This may not be the case for the RT-90C, but something to consider.
  8. I have the RT80C which is the slightly smaller model. I also have a Berlebach Report which is similar (although smaller) than the StellaLyra wooden tripod. The Berlebach is actually nicer. But more expensive than the Innorel. I am guessing for your payload, either will be fine. Question is, what tripod are you now using and why do you want to change it?
  9. What I see is that stepper motor mounts are inherently quieter than servo drive mounts. All of the Skywatcher mounts are stepper motor driven, for example. My servo-driven Mach1 is like a dentist drill when slewing…
  10. Those toilet tents look good and are relatively inexpensive! they would need serious weighing down though given the winds we've been having recently. I think one would still need a cover even with a toilet tent.
  11. My daughter similarly has expressed interest in astronomy and is four. At her age that's viewing the moon, period. Maybe Jupiter sometimes (it is quite high in the sky these nights). Now four is not six, so different experience - but in my experience my daughter grabs onto the eyepiece, supports herself on it.. which would tend to move the telescope off the object of interest. Hence some sort of ladder for the child to hold on to (so that they're not using the eyepiece as a grab handle!) would significantly improve their experience.
  12. I find that about one day in two weeks has been clear, the past three months. A terrible ratio, but one that makes quick startup even more important (before the clouds roll in). I use a Polemaster for alignment and have 3d printed adapters on all my mounts so that the one Polemaster can be transferred to any mount quickly. I’ve seen the roll off observatory plans on CN but they all/mostly are for a pretty large shed type structure. I need something really small for the balcony.
  13. I got the Tamiya paint. It is a very poor match to Takahashi green. I guess if the paint job was super bad and you had to repaint the entire part, then the Tamiya paint would be OK. But it really stands out if you try to use it for touch up.
  14. The problems with the EQ1 (I had the misfortune of owning two..) are 1) pot metal worm wheels 2) the terrible clutching mechanism, if you do get the RA motor I realise not everyone can buy a better mount.. but a Vixen Polaris with scope was selling on ebay UK for 75 quid a few weeks ago. A much, MUCH more capable mount than an EQ1 (I owned two of those, too).
  15. I'm actually interested in those sentry box style shelters. I am guessing that's a type of garden shed, there are quite a number on Amazon but am not sure how to deal with removing the floor (that might structurally weaken it a lot). Would look nicer and if I could figure a way to roll it out of the way to observe...
  16. I remembered that the SP (and SP-DX) have verniers on their setting circles. Even my (various) Taks don't have that (the Losmandy GM8/G-11 have verniers as well, but they are larger and heavier). With verniers you can get sub-1 degree pointing, around 0.1-0.2 degree is usually doable. Incidentally.. I think dual axis drives overrated. The EQ-5 and it's Vixen cousins have so much backlash on the DEC that the 16X or 32X "high speed" mode is imprecise due to the unpredictable nature of the backlash being taken up. I find it's easier to "feel out" the backlash by hand, with a DEC slo-mo knob. This may not be the case at higher magnifications where the 2X or 8X speed on the DEC of a dual-axis drive may be more useful, but for my use case (100X or so at most) a single-axis drive is great.
  17. Why not try https://www.astrotreff.de/marketplace/ ? I sometimes see amazing bargains there. I think if you want single-axis, basic, it's hard to beat an SP-DX (the SP would not be materially better than an EQ-5, and the GP-DX has no setting circles).
  18. What sort of wattage is on those dew straps? I bought a pair off Amazon (18 quid for a pair! https://www.amazon.co.uk/dp/B09D7FSHBH), not astronomy-specific (apparently the long tele owners have the same problems.. who knew?!) and it's only 10W across both of them (gets power from a 5V 2.1A USB port). I don't know if that's enough given how cold it gets these days... I don't have theft concerns because I'm on a first floor balcony. Definitely different case if it was a garden. Also, I don't intend to keep the cameras, scopes outside at all - just the mount.
  19. The W-O tubes are incredibly heavy for their aperture. I have no experience with the 100mm Taks but my FS-60CB is definitely lightweight. For a mount - why not find an old Vixen SP or GP? it's materially lighter than the HEQ5, has slow motion controls (and in the case of the SP has setting circles) and you can find one really cheap. Either would be pretty decent with a Tak 100mm f/8 or f/9 (I used to have a GP and used it with an Orion 100ED which is like the poor man's FC100).
  20. The Borgs have very light tubes. I used to have a Borg 76ED (now discontinued - replaced with the 77ED I believe) and it was less than 4lb. My 80mm Lomo triplet in William Optics tube is literally double the weight. I ended up selling the Borg because it was too close to my Lomo triplet, and instead got an FS-60CB which is lighter than the Borg, but also smaller.
  21. Onstep is completely open source and you can adapt it to any mount (since the gear ratios are all in the Arduino source code). You'll have more issues finding the right motors and mounting brackets for your mount. The brackets can be custom-designed and 3D printed if you are into that.
  22. I downloaded the Dulux app for iPhone. It (allegedly) can use the phone camera to match a particular colour. I don't know how it handles colour temperature of the lights! in any case most paints exhibit metamerism anyway (they look different under different lighting). That said the Dulux app thinks Tak green is "Dulux warm straw" and the local hardware store has a Dulux mixing machine. They probably won't sell anything less than a gallon though. I'll have to check that Tamiya paint..
  23. I realise this topic has been beaten to death many, many times over the years, but I'd like to hear updated opinions. Recently moved to the UK. Was not prepared for the (low) temperature and (near 100%) humidity. Because I'm leery of corrosion, etc. I only keep my "beater" mount outside under a tarp - one of those cheap Telegizmos knock-offs on Amazon. The "beater" has a single axis drive and very little can go wrong with it. The trouble is... it has a single axis drive. I spent a good three hours last night "imaging" what I thought was IC1396 and... it was way off in the corner of the frame, because I had used the setting circles to point the scope (no GoTo) and that simply wasn't accurate enough. And I don't want to do repeated plate solves and turning the slow motion knobs by hand because it's cold outside. I don't have the option of an insulated shed, so a Telegizmos cover or similar is probably my only choice. Will this (plus maybe one of those rod greenhouse heaters) be sufficient to keep moisture off the electronics?
  24. I can understand the desire for a basic mount.. it’s why I use that old Takahashi 90S - dead simple, runs off a USB power bank. No need for GoTo alignment. Slo-mo knobs to move it around. Setting circles. An SP-DX would be another viable option if you can find one. The GP-DX is more common but has no setting citcles.
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