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About bobro

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    Proto Star

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    Isle of Wight
  1. For straightforward processing Doug German's videos are a great start. He doesn't use GIMP, though GIMP has the same sort of processing functions Doug uses. For gradient removal see: https://www.youtube.com/watch?v=yTEVMH_WE80 Below is your image processed with the methods Doug proposes (gradient removal and star masking) using GIMP, plus saturation increase and stretching. I'm no expert at processing and others will do much better, but it gives an idea of what can be done with the image - some of the nebulosity around Sadr is becoming visible. Of course a night with less moonlight will help as image noise will be less.
  2. Images are looking very good considering your setup, targets and time of year. With basics nailed, the question is what's next? An increased number of exposures should be straightforward to achieve and will improve SNR. Longer exposures will help with noise though will probably require guiding. Brighter targets (higher SNR) will result in visually improved images. Darker nights/sky will also make a good difference. Perhaps a combination of choices for a greater improvement, though at this time of year a brighter target may be appropriate. Winter can make a dramatic difference to images! Great stuff! Bob
  3. My EQ2 has dual axis guiding (but not goto). As guiding controls the position of the mount by making small adjustments to the speed of the simple DC RA motor or turning on/off the DEC motor, stepper motors are not necessary (they are necessary for a goto mount or a non-guided mount for positional accuracy). Note: I haven't used the EQ2 for some time as I now use an EQ5 (stepper motors) with AstroEQ - a very good solution though care has to be taken with choosing the stepper motors. Here is a link to more info on the guided EQ2: http://guiding.web.fastmail.co.uk/
  4. Hi, The original article describes how the design works with an f#4.5 reflector used as an example. Results will also depend on the frame size of the camera as coma gets worse as the distance from the image centre increases. If you go ahead it will be interesting to see the results. For testing an aperture mask (a piece of card with a circular hole across the front of the scope) could be used, for example, to reduce the scope from f4 to f4.5 to see what difference this makes. Bob
  5. Welcome! Here is a link to a very similar telescope and mount if you can't find the Tasco one: https://www.telescope.com/assets/product_files/instructions/29260_01-09.pdf
  6. What make is a 200 DP? (Sky-Watcher do 200P and 200 P-DS. with different focusing requirements.)
  7. 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.
  8. 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.
  9. 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.
  10. 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?
  11. 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
  12. 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.
  13. 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.
  14. These 2 youtube videos may help: https://www.youtube.com/watch?v=Ps8d4P7fWK0 https://www.youtube.com/watch?v=xlGF7PYLpYE
  15. 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.
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