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Piero

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Everything posted by Piero

  1. Just returned from a session outside. Venus was superb, the best view I ever had. Faint white - grey patches were visible between 250x and 400x. Really good view! I then moved to the classic open cluster in Auriga, Gemini, Cancer, and eventually ended up to the bright galaxies in Leo. The new black paint certainly makes a difference. On Venus I believe the top of the mirror box now painted black also increased contrast, as the sky appeared noticeably darker than usual. Looking forward to use the new light shroud, which landed in Heathrow airport this morning!
  2. Mounted! Just re-collimated the focuser and secondary. Therefore, I collimated the focuser and primary axial alignments and now it's ready! Here are a few photos after painting:
  3. This past weekend I took care of the telescope coatings. Certain parts were minimally coated, whereas others (e.g. UTA, wheelbarrow handles) didn't seem to be coated at all. Also, the internal was gray / black. After ordering the same products used by David from Rustins, I applied 4 coats of clear lacquer to the outside and 4 coats of matt black to the inside. Now the telescope looks so robust and protected from any kind of humidity! The parts in the light path are really black now. Also, before doing this work I removed the "button" screws used for attaching the light shroud to the UTA and mirror box. So many! Once removed the holes were all filled and the sanded. This was done a couple of weeks ago. I also removed the usual label that is attached to the UTA as the specs were wrong. in addition, I attached 4 X 2mm felt pads to each wheelbarrow handles so that there is a small gap between these and the rockerbox. This should have been done a long time ago, but for a reason or another I always forgot 🙁. Anyway, there are two advantages with this little mod: 1) the wood does not touch, therefore no scratches, cracks noises, etc; and 2) if the telescope is left out overnight or during a week of clear sky (I use a telegizmo cover when this happens), this gap allows the wet surfaces to dry properly. I also decided to apply the matt black on top of the mirror box, to optimise contrast by reducing any stray lights or reflections. Will post a photo later! Finally, Rob Teeter let me know that the Heather completed and just dispatched my new light shroud! It will arrive soon, hopefully. This evening I will put back the primary mirror and re-collimate the telescope. Very happy with the results. Now I am confident that the telescope can really last for several years! The first two external coats (..the UTA looked already so different!):
  4. Congratulations John! I tried it with the Tak tonight, but was only able to see an elongated shape with no clear split. This was at 215x and 308x. However, I managed to split Iota Leonis at 308x. It is a nice yellow-white pair with magnitudes of 4 and 11, respectively. The companion chases the main star very closely as the latter advances towards the eyepiece field stop.
  5. In my Dobson 200mm F6, I never felt the need to have a magnification between 50x and 100x. Something in between like a 75x? What can that show that the other two magnifications don't? I don't see an use case, except from collecting one more eyepiece. 50x is a good low power, 100x is a good medium power. Add a 200x as high power and you are done. These jumps will show different views, worth swapping eyepieces during a session. P.s. the same approach can be used for larger telescopes. In this case though, the medium power will have a higher magnification, and the high power will be subjected to seeing conditions. As Don suggested previously, I also think that eyepieces should be chosen and bought considering the exit pupil, rather than the mere magnification. Ideally, something like the following works well: * 4-5mm exit pupil for low power * around 2mm for medium power * 1mm for high power * 0.7mm for very high power depending on seeing and telescope.
  6. Lovely telescope, Jeremy! it looks superb with that tripod. And congratulations on the BBHS mirror diagonal. It's a very good one!
  7. Off topic... Is there a specific reason why you title all your threads in capital letters? It doesn't seem to me that they are more important than others...
  8. Why the classified should be suspended? If the current situation is a concern, one should simply not buy / sell..
  9. I've spotted M1 with my TV60 a few times. The only issue is light pollution really. Years ago in Devon I observed M31 with 15x70 bins. It was almost larger than the FOV, plenty of detail to see, M32 and M110 were trivial and also showed detail.
  10. That's very beautiful! Thank you for posting it, I tried to observe it with my dobson last night, but the sky wasn't good enough.
  11. @niallk I agree! They make a substantial difference on a cold night.
  12. Collected today from my post office!
  13. Yesterday I received 4 new pipe insulators for the truss poles. These reduce vibrations to nearly zero, are much more comfortable to touch in the cold, and minimise internal light scatter. They are also rather cool!
  14. Thanks Gerry. I also think that a lot depends on the skies on observes. Under my moderately light polluted skies, I like 2mm-1.5mm exit pupil as medium power eyepiece. That gives me a the best contrast for a large variety of targets. There is also a personal factor to add.. I tend to like a "jump" in magnification rather than small increments. For instance, the 20mm rarely saw the focuser as I tend to jump from 30mm to 12.5mm, and then I kick the VIP in to go to about 300x with the docter. Other people like larger sets of eyepieces so that they can fine tune. Different tastes!
  15. I just put your data in my calculator. So the Docter with your 15" w/ PC2 gives 168.25x and 2.26mm e.p. In my dob w/o PC2, the Docter gives 145.04x and 2.03mm e.p. W/ PC2, these # become 166.80x and 1.77mm e.p.
  16. Thanks a lot for your very clear comment, Don. I don't find coma distracting in my F6 dobson, but it is certainly there. I might invest in a PC2 in the next 15% TV discount sales, as I love refractor-like views.
  17. Good report, Gerry Sometimes it is nice to simply revisit old favourites. I'm sure whatever you use, you will have a great galaxy season ahead! Hope that the sky becomes clear here too.
  18. Mm.. interesting. I tried both actually, and didn't see any difference.
  19. Here's mine. Mirror cell was modded. I'm going to change some other things in the coming months but nothing big.
  20. Superb! That looks like an outstanding telescope. Thanks for sharing.
  21. Never had issues in the second hand market here on SGL or ABS. In contrast three times I had issues with new equipment...1) TV plossl 20mm, 2) my first TV60, 3) my current 12" dob. The first item was kept as I wasn't aware of the issue that time. The second one was returned to the seller after I included a lawyer in the email communication. The third one was fixed by me after about 6 months of analysis, study, work, and testing. Now, THANKFULLY, it works and works very well, but it gave me quite some bad time!
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