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  1. I would say definitely both sides, but mount the rollers so they can 'float' a little in the required direction (tangental to the track). The metal track should be fixed to the timber with slotted holes so if the timber warps the track can stay straight. Timber will change dimension only across the grain, so in general a building won't change size. It might warp, causing distortion, but bracing would help
  2. I can get focus with a ASI120 mini. It is inside the eyepiece holder so only similar 1 1/4" cameras can work.
  3. There are some high performance planetary gearboxes available now. They have quite low backlash ~15 arc minutes. If you use one of these, and then follow up with further reduction - say a worm drive. The further eduction ratio reduces the planetary gearbox backlash. For my Dobsonian drives, I use 1.8 deg Nema17 steppers (200 step), with 30:1 planetary gearboxes, and then a 30:1 final reduction (roller to main bearings). I use 16 micro steps. The torque output of the motor/planetary gearbox is enough to shift a 42" Dob (100kg) at 6 deg per second. Key to this is acceleration and deceleration. Goto accuracy is a different issue. You can use step counts to compute angles, but the mechanical accuracy of the mount will seriously degrade the answer. You can add encoders to the scope axes which will be better but not perfect. These days the best solution is to use plate-solving.
  4. Assuming appropriate gearing, a Nema17 will be sufficient. I design Dobsonian drives of up to 50kg that use nema17's. You'll want to use a gear reduction such that the motor micro steps, when reduced and at the telescope axes are small enough for your purposes. This will mostly depend on whether you are wanting to do astrophotography or just visual.
  5. As suggested. probably signal strength is at the heart of the issue. As I understand it the ASIair will try to connect in station mode but if unable will generate its own wifi. Looks like it doesnt try very hard! Do some experiments moving closer to the wifi router? Also, maybe the wifi channel near your router is crowded. Even in my house I can see my neighbours' wifis. Your phone etc should give you an idea of other wifi signal strengths at your scope location, but not channel number. For that you could try a wifi analyser App and then move your router wifi channel to a quieter number. Use 1, 6 or 11 as they dont overlap.
  6. Certainly smoke contains corrosive chemicals. It would be a question of how much smoke and any breeze. best to be safe perhaps!
  7. Turn it off. Put it somewhere warm and dry for a few days. If you have some big bags of dry(fresh) silica gel then you could put the Seestar in a big sealed ply bag with them It sounds like the electronics is work but you have condensation on at least one optical surface. Its just got to be allowed to dry out
  8. I've assembled a few such cameras for myself and others, plus for digital finders. My findings are that the loss of sensitivity with colour cameras is very significant. Sensitivity is all important and so I wouldn't recommend it personally.
  9. The 'Ultra Compact' layout for Dobsonians, exploited by Obsession results in very transportable scopes. My own 18", self built, easily fits in the boot of my Mustang.
  10. I believe the key is ' homemade mirrors of unknown quality'. Although the mirror is a major cost item, building or fixing up the rest of the scope is a major investment in both time and money. You want to start with a mirror set that is known at least, and for me - a good one.
  11. I can see quite a difference between the Baader white light foil and the Thousand Oaks as supplied with a Seestar. Especially in viewing the lower contrast surface features rather than sunspots.
  12. This is similar to performing the 'drift' method of polar alignment. The closer you are to the celestial equator, the greater the 'error' effect. Imagine the extreme of being at the pole, enormous azimuth movements will barely move the sightline. Just move the scope so it is at at Dec zero. Doesn't matter how high up, but at the meridian is good.
  13. My grandson is Leo too! I hadn't thought of printing it for him - at 4 years old it might need some explaining!
  14. Yes, the Leo Triple makes a good target - perfectly matched to the field of view.
  15. I have successfully installed the following additional on 64bit Bookworm on a Pi5 ... Skyfield astropy fitsio pyfits the zwoasi SDK gps3 imagemagick microsoft visual studio All perhaps a bit specialised but more for those developing their own code.
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