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bobro

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About bobro

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    Proto Star

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    Isle of Wight
  1. Been there with my CG5 (EQ5). The EQ5 RA axis consists of a central core (with bearings at top and bottom) and a cylinder around it that mates with the RA worm gear. With the RA clutch ON the cylinder and core are locked together, allowing the worm to provide RA drive. With the clutch OFF the central part is free to rotate in principle, though can be sticky due to the lubrication (grease) between the cylinder and central part. Depending on the grease and with the clutch off, it can be a little difficult to balance the RA axis as it can seem sticky. Using lighter grease (or even removing most of it) makes the outer part of the RA axis rotate more freely with the clutch off. However, this doesn't affect operation with the clutch ON as the inner and outer parts are locked together. So your mount is operating as expected - no need to do anything so long as it is operating correctly when the clutch is engaged.
  2. Even with a full Moon, it seemed a shame to 'waste' clear skies, so I decided to see what my (uncooled) Hypercam 183M would produce with a (rather old) Astronomik Ha filter, not expecting very much in the way of results at a reported temp of 14 degrees C with the uncooled camera. 150PL scope (f#8), 18 subs @ 6min, 11 dark, 10 flat, x3 binned, not dithered. The resulting image (no noise reduction other than kappa-sigma stacking) surprised me as I was expecting it to be pretty awful due to noise. I suppose x3 binning helped, but it must be down to the low noise of the IMX183 sensor, although a stretched single sub looks horrible with hot pixels.
  3. In higher light pollution environments there's no advantage in long exposures as multiple shorter exposures produce the same results (in signal/noise), potentially allowing a lower spec mount to be used. With the scope/camera you mention in a high light pollution environment, there may be no advantage in exposures longer than, for example, 30 seconds. On the limit perhaps for a Star Adventurer but an HEQ5 could be overkill if you are looking for a portable mount. Guiding is typically not necessary for short exposure times, helping to simplify the setup. The IDAS D2 filter will help to some degree, though I don't know how much. Perhaps someone else has experience of this.
  4. Doesn't CdC connect to the mount for positioning and APT to the camera for imaging, with (for example) an APT connection to a PHD2 guiding program server for dithering? Perhaps your setup works in a different way?
  5. The 150PL won't come to focus with a Barlow body inserted into the eyepiece holder and DSLR due to lack of inward focuser travel. To mount a DSLR unscrew the eyepiece holder and screw a standard M42x0.75mm T-ring to the M42 thread on the scope. https://www.firstlightoptics.com/adapters/t-rings.html
  6. Looks like a Jones-Bird design. If so, there will be a corrector lens at the bottom of the focuser tube. Although reflector telescopes often do not have enough inward travel to attach a DSLR, the x2 magnification of the lens doubles the effective length of the focuser travel and it seems you have been able to focus with a DSLR. Unfortunately the image quality with this sort of low cost telescope is not normally very good and there's no point in trying to magnify the image as it will only show up shortcomings even more. Have fun with it as it is, though a telescope more suitable for imaging is the way forward.
  7. The Astromaster RA drive mentioned above does not have accurate speed control - it has a simple DC motor with a difficult to use speed adjustment. This isn't an issue for visual, but for imaging (assuming you are able to fiddle with the control to get a reasonably accurate speed) star trailing in images will occur due to motor speed inaccuracy/variation - you may be lucky enough to get 30 secs before trailing starts with your 150P (I managed 30 secs much of the time with my Meade 130/650 using the simple RA motor). I'm familiar with the design, having reverse engineered the circuit to modify 2 motors for dual axis guiding for my EQ2 - in that case the speed accuracy wasn't important as the guiding setup varied the motor speed in RA as required. The EQ3 motor mentioned above is an accurate motor drive - hence it doesn't need a speed adjustment. This motor is suitable for astrophotography and will allow longer exposures that make for better astro images, though the lack of goto may become an annoyance, so an improved solution could be to fit a SynScan Upgrade kit at £285 if funds allow.
  8. These 2 youtube videos may help: https://www.youtube.com/watch?v=Ps8d4P7fWK0 https://www.youtube.com/watch?v=xlGF7PYLpYE
  9. I'm not 100% certain, but I recall the EQ1 and EQ2 having different gearing. That's not really an issue with the adjustable simple motor, so the physical attachment is what is important there. For a precision motor both the gearing and physical attachment are important : assuming that EQ2 gearing is correct for your mount, it will need to work mechanically with your mount. Although EQ1/EQ2 mounts (especially SkyWatcher, Celestron and Meade) sell in numbers, yours looks to be an older mount design that may be different from what is sold today.
  10. The basic/economy motors are just simple DC geared motors with a (tiny) control to vary the speed. When the basic motor starts it tends to run a little fast before settling down. Once the control is set to the correct speed it will track the sky reasonably well - when I started out with imaging my EQ2 Economy motor would allow 30 sec exposures with a 650/130 scope before drift became visible. For visual this is obviously not critical. Setting the speed is a little tricky with the tiny control. A disadvantage is the loss of the slow motion control. The range of speed setting is large. The motor with a handset provides precise speed control - it most likely has a stepper motor internally. The correct motor for the mount gearing must be used as there is no adjustment. The motor clutch allows the slow motion control to be retained. I still have my EQ2 (Meade type) and can help with a comparison if that helps. Bob
  11. Thinking back to last night's imaging session, PHD2's guiding graph was bad with 'spiky' movements in both RA and DEC. Normally guiding is much better than that and DEC will show as very stable on the graph. As I was imaging high in the sky, for the very first time I used a dew heater band wrapped around the lens of the Orion 50mm guidescope to save me from continually wiping dew from the lens. Could the dew heater have caused the apparent poor guiding? (Images weren't great either.) If so, any tips on using one? Thanks
  12. Great explanation from @vlaiv - first time I have understood the reason for taking bias frames.
  13. That's showing more colour. It looks as though flats haven't been used in stacking. Using flats really helps with targets having gradual variation in brightness as the true variation comes through. Any chance of adding flats if they have not not already been added?
  14. Kappa Sigma stacking works really well (as you already use) in eliminating satellite and plane trails as it works at the pixel level.
  15. That's a very good image with really good detail (much better than I have ever achieved). It's not a big deal but the trailing stars towards the right hand side of the image looks to be due to polar alignment not being accurate as the trails rotate about a point. An earlier post by yourself shows you asked how to best use a polar scope, though without response. I can't help there as I use Sharpcap for polar alignment (very good), but you could try searching the forum (no doubt has been asked numerous times before) or posting again. Great work.
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