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Rocket_the_Raccoon

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About Rocket_the_Raccoon

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    Star Forming

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    CANADA
  1. Rocket_the_Raccoon

    Improving the Celestron Astromaster 70AZ

    Thanks, I personally is a fan of refractors, especially for slow ones like this. It is unfortunate that they are not made any more (at least not in large enough volumes to be affordable). And yes, the new rings and dovetails made balancing possible on any mount. The original fixed dovetail is so limited but it does act effectively as a balance weight in this particular setup.
  2. Rocket_the_Raccoon

    Improving the Celestron Astromaster 70AZ

    Thanks. As for the tripod, which 102 are you referring to? This particular one comes with the scope and has a design flaw that the metal rod/handle sits above the altitude axis, making the setup almost always back-heavy. This was mentioned in my review of the scope in an earlier post. For this reason, the dovetail and tube rings were used so that I can balance the OTA. Lastly, hanging a weight from the tray centre is indeed a good way to stabilize the whole setup but as currently, vibrations pretty much die down within 2 seconds even at 112x, I had simply skipped this step.
  3. Rocket_the_Raccoon

    Improving the Celestron Astromaster 70AZ

    A little more than a year ago, I acquired this 70mm f/13 long refractor for merely $40CAD and wrote a quick review on it : https://stargazerslounge.com/topic/295880-celestron-astromaster-70az-review-and-improvements/?tab=comments#comment-3239177 Recently I have made some further improvements on the scope to create a quick and lazy observing setup for me : - dovetails and tube rings for balancing the OTA, note that the tube is smaller than the standard 76mm ID tube rings and thus requires ~2 layers of felt pads for a tight fit. - Celestron prism star diagonal replacing the low-quality and stopped down Amici prism - 6x30 finderscope replacing the hard-to-use star-pointer, also better suited for a light-polluted sky, finderscope base was super-glued to the OTA instead of drilling holes. - because of the f/13 ratio, the stock 20mm and 10mm both perform very well - added a Meade 12.4mm Plossl for nights with only fair seeing - added a 1st generation 8mm Brandon for nights with good seeing - added a homemade 33mm for DSO's, TFOV 1.6 degrees (stock 20mm gives 1.27 degrees), please see https://stargazerslounge.com/topic/314649-diy-6-element-33mm-eyepiece/?tab=comments#comment-3441384 - added a Skywatcher Crystalview Moon filter for obersving the full moon with the stock 20mm, also for slightly enhanced views of bright nebulas.
  4. Saying goodbye to the red planet...

  5. Rocket_the_Raccoon

    Removing the "Trash" from a Trash Scope (Part 2)

    That's indeed a good idea. I should give it a try once the night sky clears up. Unfortunately, rainy season just started over here in south western Canada.
  6. About 4 months ago, I brought a $20 trash scope (50mm f/7) back to a usable state at minimal cost, it was posted here : https://stargazerslounge.com/topic/315129-removing-the-trash-from-a-trash-scope-trash-panda/. Recently, I made two "improvements" on it. First of all, I added a "screw eye" on the hood to align with the L-bracket on the tube to make the "finder" more accurate. The adjustment/alignment is done but rotating the hood and screw eye itself. Next, I replaced the 45-degree hybrid-diagonal, which I found to be extremely difficult to use for astronomy, with a .965" 90-degree mirror diagonal that I scavenged from a $5 toy telescope (single-element objective, a "real" toy). I then use the .965"-1.25" adapter that was included with the 50mm in order to use 1.25" eyepieces with a .965" diagonal. Note that both the .965" mirror diagonal and the .965"-1.25" adapter have a 20mm opening instead of a full 24.5mm. Thus, my TFOV will be limited to 3.18 degrees. Fortunately, my Celestron 20mm eyepiece has a field lens of the same diameter so no field is wasted. The result, despite the mirror diagonal coming from a toy scope, is pretty good. No light-scattering is visible and the mirror seems to be well-aligned. Images are just as bright as the prism and of course, a 90-degree viewing angle is certainly more comfortable to use than the 45-degree one. Well, now I have an ultra portable carry-along or ever-ready-in-the-trunk scope.
  7. If I have not mistaken, the Firstscope 80 is a 80mm f/11 and the ST80 is a 80mm f/5. Are you doing traditional manual guiding with a cross-hair eyepiece? or going digital guiding? The Firstscope 80 being a long refractor puts more load on your mount and you would need more effort to balance the whole imaing scope and guide scope setup. However, its long focal length is a plus for high magnification if you are using visual manual guiding,
  8. Rocket_the_Raccoon

    My first telescope

    Hi! Alex, both can show you the ring of Saturn but at 40x (10mm EP with the Travelscope 70), Saturn will be a bit tiny. 65x (10mm EP wtih the Heritage 130) is more appropriate. Also, the Travelscope 70 comes with a photo trpod that would have problem supporting even a small point-and-shoot camera. It also comes with a non-achromatic 5x24mm finderscope and a 45-degree diagonal that is not intended/suitable for astronomy use. The Heritage 130 is a clear winner. Despite that, I am a proud user of Travelscope 70. The quality of its little 70mm objective lens is amazing for the price. However, I use it with a red-dot finder, a 90-degree diagonal, and an heavy duty (for this scope) equatorial mount.
  9. Just would like to add my 2 cents here... You can also have bad seeing on a clear night. For example, you observe on concrete ground after a long hot day.
  10. One of the two .965" eyepieces that I still have (the other being a Circle-V K40mm). Both of them I enjoyed using on my 60mm f/15 refractor with .965" focuser which I no longer have. 3~4 years ago I made a temporary modification for this eyepiece so that I can use it on my current scopes with 1.25" focuser. However, it was kind of ugly and the eyecup was too long for the eye relieft of this 6mm Orthoscopic. So I took my .965" eyepiece projection adapter and a 1.25" eyepiece barrel from a H20mm to make this .965" to 1.25" adapter.
  11. 🔭 Despite being low in the sky and with added "special effects" from neighbour's chimneys, Saturn is stunning through the eyepiece as it always is.

  12. Rocket_the_Raccoon

    Rocket's Album

  13. Rocket_the_Raccoon

    Removing the "Trash" from a Trash Scope - Trash Panda :-)

    Thank you, Cuivenion. You are right about the baffles. It is just an individual case that the two baffles of this scope has a severe "side effect" of limiting its aperture while not doing a much a job in limiting internal reflections. Of course, to be sure, one needs to do a trace diagram of the objective lens.
  14. I bought this Celestron Travelscope 50 for $20CAD, primarily for the two 1.25" eyepiece barrels that I can scavenge for my DIY eyepiece projects. I have seen and used "bad" telescopes before but it was never as bad as this one. Though a 50mm f/7 achromatic objective should show minimal to undetectable chromatic aberrations (CA) according to the 1.22D rule, Celestron still put a ~30mm baffle in the tube and worst, a ~5mm baffle inside the focuser! One can almost call this a CA-phobic scope. To make this "trash scope" usable, first thing to do is of course removing the two baffles. The one in the telescope tube is easy to deal with and I would suggest removing the focuser to get access to this baffle instead of removing the lens cell (to avoid possible mis-collimation). The removal will leave some bare metal marks and they need to be repainted with flat black paint (I uses Tamiya XF-1 acrylic model paint). The focuser baffle seems to be moulded as one piece with the focuser itself but it is not. It is just a very tight fit and can be removed by "force" but one needs to remove the focuser first. This also exposes the roots of the two finder bracket retaining screws and thus serves as a good time for any finder modification. After that, the inside of the focuser barrel MUST be painted flat black as it is unusably shiny. To improve image contrast, the objective lens can be removed then have its edge darkened by a black marker. This can be done by taking out the hood and unscrewing the retaining ring without the need of removing the whole lens cell. As the objective lens is not exactly tight fit (horizontally) inside the cell, a narrow piece of chalkboard sticker can be placed between the lens and the cell wall to fill the gap. Finally, when putting back the objective lens into the cell, the 3 spacers between the two lens elements of the achromatic objective should be aligned with the 3 screws that hold the lens cell and the tube together. At this point, the scope has become much more usable than its stock form but there are other improvements that can be done. The stock finder is basically useless. It is even worse than a 5x24. I have a DIY 21mm achromatic finder but unfortunately the bracket is too tiny to fit it. Given I have an extra Vixen-style dovetail finder bracket, I might just put it on the tube and borrow a finder from my other scopes but I don’t so I simply use a L-shape corner brace (left image above) to make a peep-hole. It is of course far from accurate but it is usable at very low power, with which the 360mm focal length of the scope and my DIY 33mm eyepiece (middle image above) can give. I have two other DIY eyepieces (right image above) and they are both good companions with this little 50mm. One is an 18mm “traditional” Kellner scavenged from an old pair of 10x50 binoculars. I think it is based on the original optical formula because it has pretty tight eye-relief for an 18mm and a relatively narrow field (still way wider than the two stock Huygens, of course). Another one is a 10mm 1-2 König scavenged from a pair of 10x25. I have another post written for this nice little eyepiece here: With the above additional modifications on finder and eyepieces, the scope has now been improved to a point that any further advancement would require a new purchase. However, I just love the extreme portability of this scope so I might buy a cheap 1.25" star diagonal (as the scope includes a .965"-1.25" adapter, I do not have to buy a hybrid) just for it as I found the stock 45 degree hybrid, though not bad in quality, gives very odd viewing angles for anything 30 degrees above the horizon. Finally, to make an “one and for all” decisive improvement for this scope is to replace its .965” focuser to a 1.25” one. The AFOV of my 33mm eyepiece is not just now limited by the .965” focuser but also the 20mm opening of the hybrid diagonal. Having a 1.25” focuser and a full aperture star diagonal, the 33mm eyepiece would give a spacious 4 degrees of field. As for the "mount", I replaced the included super filmsy tripod with my portable photo tripod. Because the scope is extremely light, the ball head tension can be tightened to point that it gives smooth motions. At 40x, it takes only ~2 seconds for image to stop vibrating. Below is a handheld cellphone photo of the moon taken through this scope using the 10mm 1-2 König.
  15. Rocket_the_Raccoon

    Eyepiece Beginner Advice

    The Skywatcher 8-24mm is pretty good according to http://astro-okulare.de/English/indexe.htm I believe it is the same as the Celestron and Orion 8-24mm. It might even be under other brand names too. The drawback of course, as stated, is the narrow field of view at the 24mm end but you have a 25mm anyway. If you are into DIY and can obtain old compact binoculars at very low price (e.g. charity shops, items that collecting dusts at home, ...), you might want to consider making a 33mm eyepiece like what I did in:
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