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AlexK

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About AlexK

  • Rank
    Star Forming

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  • Website URL
    http://www.dobmod.com

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  • Gender
    Male
  • Interests
    Astronomy, Android programming, Scuba diving, Windsurfing.
  • Location
    California, USA

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  1. That's indeed an ideal trade situation. So just go grab it first, then post some images here, we'll assemble the Grand Consilium for that specimen in no time
  2. Second to that. Totally sane price for that 10" used (~$750 brand new, but on backorder everywhere, so will be at $1000 soon no doubt). Just make sure it's not damaged internally or externally and has at least some stock accessories. If you can't visit seller in person to inspect it with the flashlight ask for clear images of anything they consider being a defect. And at least the primary's image in white light focused on its retainers (must be spotless even if dusty). Then you can try negotiating if you want.
  3. Congrats, Michael! A decent light-gathering upgrade! The stiffness could be normal for it actually. This is not a Dobson scheme with feather-touch push/pull action you might be used to. It's a GoTo attempt on a particle boards fork. You supposed to drive it with buttons, not by your bare hands. The manual pointing operation is more like just an afterthought in such a design, so it's not like on a Dob and not like on a real Alt/Az fork mount. So to avoid any confusion I would try simply following the instruction manual step by step for automatic pointing (GoTo) first. That would also he
  4. Yeah, that Zeiss Coude is a true modern marvel of the optomechanics of 70-es. But by now, its mechanical base aging renders it less beneficial for the intended scientific tasks. E.g. the detectors miniaturization revolution outweighs the need of professional maintenance (expensive and time consuming). So it's being replaced at observatories to cheaper to own modern solutions with even more capabilities. Good for amateurs willing to take the job of restoring that technical wonder! It was especially awesome for imaging, photometry, spectroscopy, Sun observing (manual sketching, heavy H-alpha st
  5. Re Dobson cooling. It should not be too much of an issue on the Islands as the temperature swipes are not that drastic there. I see it's like 20C to 10C (day/night) in the summer. So with the cooler fan it should be like 20 min. If that's still seems like a serious problem for your flow you don't have to wait, mod your OTA with the surface layer blow fan(s) and/or front duct ring. Folks swear that running it when observing is fixing the problem nearly instantly. Re atmospheric conditions and the large aperture. That's true, smallish aperture will show a smallish planetary disk kind of mor
  6. I spent several years observing hands on with the professional high end 150mm Zeiss Coude refractor and with the high end Russian long refractor AVR-3 (also 150mm). Both stationary installed on their stock high-end motorized equatorial piers under the sliding roof of the local youth astronomy club's observatory. I can tell you without a single doubt: views with my current very-average-optics 12" Dob are very long way better in every regard on planets and DSOs (weather permitting)...
  7. Unless that would also involve our Sun turning into the Black Hole (what an astronomer's paradise is that! See a BH and die!), I will be still enjoying my ODA (Observer's Digital Assistant, a.k.a. dedicated astronomy smartphone) which objects database equals in ink and paper (required to print them all) to several tons of paper charts. Because I have a briefcase-size-folding 150 Watt solar panel (works well enough even in the overcast to charge a phone). That's the last resort after I have exhausted my 500 watt/hours power brick, 4 x 3-8 Amp/Hours pocket 5V power banks, and the ODA spare batte
  8. Cheers back NGC 1502! That's right. The Astroscan is the observing ergonomics high end of all times! And definitely a keeper! I got it from a fellow colleague amateur astronomer for free specifically for my son some years ago. Because this marvel is not for sale! Only for giving! But I considering it mine too as I play with it more than him Care for it well! Yours is even more unique! And it looks like manufacturers are not rushing a new model into production anytime soon for some weird reason By the way, you can find several mods and outfits I've done to/with my Astroscan on my blog.
  9. How so? You have to use a bright enough flashlight to see its large white low contrast blinding beauty On a side note, it's easy enough to remember all these ~100 black (or blue what have you) dots and skip that redundant step for good while planning. A good star chart will show you what's up and what's not anyway.
  10. The above double-sided one is a way better design compared to the classic one. First of, it has much less distortions. Clean to comprehend, and even has lines teaching you the bright constellations stars finding with pointing figures. E.g. Arcturus is on the extension of the UMa "handle". Regarding planets not charted, Louis, you supposed to watch for the ecliptics line on that chart (dashed). Planets are bright stars. So if you follow the ecliptic line on the sky and stumble upon a bright star not charted on the planisphere, that's a planet (or an UFO). You can learn distinguishing outer
  11. Planisphere is like a wall calendar. But if you don't know constellations, not aware of sphere to surface projections, don't know what the LAT, ST, LMT, UT, LST means, it's nearly useless in the field. But you can use it to learn all of the above. And even get an inner sense of the astronomy time building up gradually. Just hang it on the wall (see the hole in the corner) and move it like every week. Then memorize what's displayed on it, i.e. at around 10pm LMT, when passing by on your daily route. The wall in front of the toilet is a good learning place for it as well Just by the way,
  12. C'mon folks! A stepper's "back flush" current is rather miniscule and will be grounded by the driving MOSFET anyway (the controller is separated from "gentle CPU circuits" by the high power driver). I have my printer for 7 years and moving X/Y 250mm wide back an forth all the time. No issues. Never heard about anything drastic like that either. Urban legends. Disconnecting your motors you are just reducing connector's lifespan and possibly eventually crack the PCB from mechanical stress too.
  13. Hmm, like what you mean? There is an exhaustive database of ~2000 OCs in existence. What else an observer might desire above that? The "Best 100 Review"?
  14. Kinda unclear what exactly you have invented here without the full context My guess is that you have used that MSM rotator arm-head to place that orange block precisely against your forehead when at the eyepieces for better binos stability? That would work if the back of your head is resting on something fixed to the ground as well (a chair's back). If not, a very good cushioning is a must to prevent view shaking. Not just to feel it better on the skin. See the rubber eyeguards? They are not only for the side light cut off but mostly to prevent exact that problem at the high magnif
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