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Gabby76

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Everything posted by Gabby76

  1. With these being 4 element in 2 groups I am not surprised that there would be colour and artifacts along the EOF. Symmetrical work better at 50-55° AFOV. You would need to be using a long focal length telescope since you get a exit pupil of 7.7 when used in a f/6 telescope. The 45 mm would work in my f/15 as that gives a 2.95 mm exit pupil.
  2. The dew heater should go on the dewshield outside so it transfers heat into the shield. You just want the air trapped in the shield a degree or two above the dewpoint. Putting it inside may cause it to show heat waves.
  3. This writeup is from Michael Swanson who was a beta tester for Celestron for many years https://www.nexstarsite.com/OddsNEnds/SCTCorrectorRemoval.htm Another quick one from Don Pensack of Eyepieceetc https://www.cloudynights.com/topic/81066-how-to-remove-and-clean-a-corrector-plate/
  4. If I remember correctly, Celestron marks the corrector and secondary at the 3 o'clock position to help keep things aligned during replacement. It is not a hard job just requires a bit of patience and there are many good tutorials online walk you through it if you want to give it a try.
  5. A lot of these LiPo batteries are listed in milliamps, 1000 mA = 1 Amp, so if it is a 20.000 mA battery it will power something of 1 Amp power usage for 20 hours. To size a battery for your setup you need to add up all of the amps required. That is what you need for 1 hour. If you plan a 4 hour session you need to multiply by 4. That is the minimum amount you need so if you want a safety factor from cold weather (lipo do not like being cold) or age, take your required amount, multiply by length of average session then times that again by 2. That final number is the size of battery you need. The Celestron pack is alright but overpriced, I would also suggest you run a separate pack for your heaters so you are not using power for your optics/ mount.
  6. You do need to set the backlash of these mounts for consistent gotos. It takes about 10 minutes to do during the daytime. The gears in the mount from factory have quite a bit of play in them. I am not sure what you mean by second alignment (or are you meaning aligning to the second star?) Using staralign you just align the 3 stars and you are ready to view. Here is how I have done it for years. Set up mount and when ready to star aligning look for the 3 stars you want. I usually face south when doing alignment. The first start is to the west, second star to the east as far away as possible then the third higher up on the east side. Something like this: /___ (right, left, up) Then other thing you mention is slewing with the mount, it does not have double encoders so if you do all goto slews it will stay good for 3-4 hours. If you manually slew then do a goto it will likely lose its precise alignment. The object should be close by though. For best goto, approach your alignment stars from below so your final approach is up to the object then right to center it. Being consistent with your object approach will also help with goto function. Great little mounts once you start figuring out their quirks
  7. I have found most refractors are front heavy and in this situation you can put ankle weights at the focuser end to push the telescope further up in the rings. Movement of the eyepiece reduces the further the telescope is pushed forward. There are a lot of pre-made astronomy chairs available but as usual they are expensive. If you do not mind making your own there is the LYBAR chair, Catsperch Chair or Denver Chair. Plans for these are easily found online, the LYBAR is the easiest to make and the Catsperch/ Denver need a little bit of skill to build.
  8. I have not read your other posting but the Bresser 52L is a good refractor. I have a friend that images solar and lunar with his and produces some amazing images. I am not sure if he has used it for DSO though. I think he is imaging in mono... A great visual telescope as well.
  9. I use wooden (bamboo) embroidery hoops, you can currently get a 12 pack of 8" rings for $20 USD on Amazon (sometimes I am cheap) :)
  10. I have to agree with Dave that EQ mounts are not hard to learn or use even for a first time beginner. When I began viewing it was with a EQ mount with nobody to give instruction and I was good after 15-20 minutes. The only advantage I have found over the years is that you can just walk out and your ready to go with a Az/ Alt mount. For G&G a Az/ Alt is great but for tracking a object the EQ is the way to go. With a newtonian on a EQ mount, if you place the focuser straight up, 95% of the time it will be in a useable position. The other 5% will be in a awkward position and likely the objects you want to see most but that is just Murphy stopping for a visit. Also it is quite easy to make a set of rotation stops so you can spin the tube easily inside the rings if you are using a large newtonian.
  11. Placing the opening between the spider vanes will get rid of the diffraction spikes and stopping it down to 100mm or so will provide a more than bright enough image. Remember to either make a filter for your finder scope or remove it entirely so you do not accidentally use it.
  12. According to a few diagonal producers (A-P, AMP, Baader) the central portion of a 2" mirror diagonal is easier to polish and coat with greater precision than with a 1.25" diagonal. Using 1.25" eyepieces works well with a 2" diagonal as the light cone is centered on the most accurately figured area of the mirror. As with most higher end components in our hobby we are likely talking a small percentage gain of less scatter and rendering of the image.
  13. I never thought of that before, I should check to see if my old EQ-5 column will fit the TAL tripod.
  14. Each series seems to be numbered so the higher the number the lower the capacity. I have the 055Pro and a 028b with the 028b being the larger/ stronger tripod.
  15. In a email with Thomas Baader a few years ago, he stated that you should test to see if you need a prism or not. Using a mirror diagonal, check the colour of the first airy disk on infocus. If it is red/ orange a prism will be a benefit. If the ring is white a prism will be no benefit and may actually add aberrations in the view.
  16. Depending what you want to view the most with the 15mm, TS may have 1 Antares Elite Plossl left. A really outstanding eyepiece for planetary and lunar observing. They were listed at just under € 100
  17. Plossl are much better quality eyepieces than Huygens, no contest. Barlows are barlows and there are no differences, though some are called apo because they have a third lens they are not actually apos and only take more € out of your pocket. Tele-extenders and tele-reducers are similar to barlows but are normally 4 lens and really not needed for visual observing. Your question of using a 5x barlow with a 10mm would give you a 2mm eyepiece focal length which in 99% of regular observing sessions would be empty/ useless magnification. Same with the 3x with 6mm. With a newtonian these powers would be useless as you would be seeing the secondary mirror as a black dot in your view. Once your exit pupil goes smaller than 0.5mm you will be looking at eye floaters and what looks like a firefly in your eyepiece. For visual observing you will likely find a 2x is more than enough once you start picking eyepiece focal lengths that work in your telescope.
  18. They do look interesting but I wonder how well they would work in colder temperatures/ high humidity without being able to increase/ decrease the power. One of my local viewing areas is beside a bog so humidity can be a issue some nights.
  19. It looks like a mix of parts, the Celestron Firstscope is a decent refractor. These were made after Celestron partnership with Vixen and that is why it is made in China not Japan. The optics with these are usually good but the mount may be at its limit with this setup. For $80USD it is a reasonable price. Upgrade a few things over time and you will have a capable setup.
  20. Unfortunately they are quite low power straps so they may not be able to keep up with high humidity. I also could not find any posting of what the actual output in amps/ milliamps are.
  21. The Dew Control straps do require a controller as well, without one the strap will continue to increase in temperature. From your link: Compatible with all popular controllers, but work especially well with our own.
  22. You should not power dew straps directly, they need a controller so that you can regulate the heating required. You only want to keep the equipment a degree or two above the dew point. I use either a older Kendrick Mk IV 2 channel controller or a Thousand Oaks 4 channel controller.
  23. A 2x barlow is not overly expensive: https://www.firstlightoptics.com/barlows/astro-essentials-125-2x-barlow-with-t-thread.html If it has a removable lens cell such as this one you can attach it directly to the eyepiece for approximately 1.5x This would give you 20mm, 13.3mm and 10mm. Knowing what eyepiece you have would help with recommendations as many included eyepieces are of average quality and a simple good quality Plossl can give a much better view.
  24. I have a Baader herschel wedge which I have used for around 15 years now, excellent views. The older Baader like mine uses a multi folded metal screening inside a enclosure as the heat trap. Observing with a 150mm f/8 refractor during the 2017 solar eclipse in USA, I observed for a total of 4 hours (sunspots-eclipse-sunspots) and the temperature difference between the telescope tube and the light trap averaged 3°C. Never more than warm and no danger of anyone being tattooed by hot metal.
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