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Rui

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Everything posted by Rui

  1. Capricorn? You mean that time of the year when the Sun is in Sagittarius?
  2. Good photo, but too much light pollution near the horizon. Or was it shoot during dusk, shortly after the sunset?
  3. From the perspective of the person itself, times goes at it's normal pace in every circunstance. When a person would be travelling at a speed nerar the speed of light or would be subjected to a strong gravitational field, he or she wouldn't see any difference and would experience time the same way we do. The time difference would only be detected when compared with someone who didn't experienced that speed or strong gravitational field. Just a remark: there isn't any place in the Universe without gravity. Earth's gravity field extends to the entire universe (even though it is negligible al long distances). In the same way, here on Earth we are subjected to the gravity fields of all the bodies of the entire universe (even if we can only feel the gravity influence of the Sun and Moon).
  4. Well done Luis! I prefer the one at right for colour rendition, but the greenish one at left seems to show finer detail. Keep them coming as Jupiter approaches opposition
  5. I have 2 binos: 10X50mm and 11X70mm. And they are both easily hand-held. But when I consider the extra weight of the 11X70 binos, i guess they wouldn't be so easily hand-held if they were 15X70 instead. Another thing: for a casual look, I always pick the 10X50 because they're so much lighter and easy to take anywhere. And, to be honest, the difference in the views are no that big, when I compare them side by side (but in a really dark place, they do make a difference!). Considering the photo tripod for binoculars... long ago I had 30X80mm binoculars that were used only on a tripod. The views were great, but it was not practical to use at all. Up to about 40º high or so, it was possible to view the sky confortably, but from there up (where the conditions are more adequate to observe), it's a real pain in the neck. I ended up selling the 30X80 binos plus the tripod and adapter. In conclusion, for day and night use, I recommend the 10X50mm. Clear skies Rui
  6. Here, in my terrace I only have a clear view due south and east. But, as if street lights weren't enough, some neighbours keep one or two outdoor lights on the whole night. I have no idea what's the purpose of keeping those lights on all through the night, but very often they do.
  7. Welcome Liz. If you want to learn, yes, you're in the right place. I'm here for the very same reason:) Cheers Rui
  8. Hi Luís, A warm welcome from northern Portugal too. Rui
  9. Nice and thorough step-by-step tutorials. No need for translation either When I have time I'll try to work something out... Thanks for sharing Rui
  10. That's a jaw dropping picture. and with a fine colour rendition. Congratulations Damian.
  11. Well done Luís! That's a fantastic Moon. And it's huge. Doesn't evenfit in my 19" screen. And that terminator is really very well defined. Keep sending them!
  12. Good news! The dealer did a first class service: contacted TV and will provide new caps. Couldn't be faster!
  13. Looks like there isn't a fixed pattern about the Ep's caps. I have 4 other TV Ep's (Naglers and a Radian) and all those, bought some years ago have black end caps with the logo. Well, seems like Televue is saving 1 ou 2 miserable cents in each cap. Considering the cost of those eyepieces, that's a wrong commercial practice, IMO.
  14. If it's only dust, then those brushes with a blower should do. When you don't have one, try with a hair drierblowing cold air with the selector in the minimum speed.
  15. I've ordered 1 Panoptic 25 and a Nagler 13. Received them today and was surprised with it's caps. Both came with a transparent plastic cap in the barrel and the upper cap on the Nagler was the black one but without the Televue logo. The Pan had the regular black cap with the Televue logo. Contacted the dealer (as they were bought new!) in order to get the regular black caps with the TV logo and he says that that's the way they came; even send me a picture of another Pan 24 he has there with the transparent barrel cap. I've seen that in the second hand market the fact that a TV eyepiece has the original box and caps is valuable and referred in the adds. Anyone can tell me if this is normal? What would you do in my place? Thanks for any advice. Rui
  16. The safest is to use batteries. They provide the right power and no problems with surcharge. When we use a 12 volt converter, there's always some risk involved... looks like you werefast enough to disconnect everything.
  17. Rui

    Hi from Devon

    A warm welcome Thabo.
  18. Probably your new dob will come with 2 Plössl eyepieces, something around 26mm and 10mm. IMHO, with those 2 plossls and and those 188 pounds, you'd do better with 2 good and wide EP's like the 8mm and the 17mm Baader Hyperions: Telescope Accessories | Eyepieces | Baader | Rother Valley Optics You end up with Eyepieces of 8mm, 10mm, 17mm and 26mm. When later you invest in a wide 2" EP around 30-32mm, you have an excellent range of magnifications.
  19. That's very strange. Normally the illuminates reticule has a rheostatto adjust the intensity of the light, by rotating the switch. Contact the dealer and check it because it's possible that this device is not working properly.
  20. You did the right thing. EP's are always a good investment because telescopes come and go, but the good eyepieces stay for good. About Barlows, if you can do without them, it's always better. No matter how good the quality of the barolw lens, it will take a small share of light. Personally I prefer to have dedicated EP's to fill the gaps in the magnification range. So, below the 13mm Nagler I have a 9mm Nagler, a 8mm Radian and a 6.8mm UWA Meade.
  21. Maybe they don't lie, but they certainly exagerate it's effects, turning something that doesn't deserve any attention into a big event. if you consider the Earth as a reference point, then the Moon goes around Earth in an eliptical orbit, taking a bit over 27 days to do so. Being it's orbit an elipse with our planet in one of it's focci, it has a closest point to Earth (perigee) and a farthest point (apogee). During every Moon orbit, it goes by those 2 points in it's orbit. So about once a month the moon will look that big. In that specific day, it just happens that the geometry between the three bodies involved in the moon phases (The sun, Earth and the Moon) will happen to be very close to a straight line by the time the moon passes by the perigee. I mention "very close to a straight line" because if they were perfectly aligned we would see a total eclipse of the Moon It's this simple. No tsunamis, no supermoons... The paper "The Sun" didn't lie. they just misinterprete the facts and figures, creating the basis for an hoax. And unfortunately, the day after "the event" people will not remember this and will not confront the paper with it's inaccuracies. People will be ready to believe in the next hoax.
  22. If you can afford, buy the eyepieces you need to obtain the desired magnification. It's better to use less glass. No matter how good the quality and coatings of a Barlow lens, it will always take it's share of light. Years ago, before long-eye relief EP's came around, a barlow was very useful to allow you to use a longer focal lenght eyepiece, with it's natural longer eye relief, and getting a higher magnification. Nowadays, you can easily get short f.l. EP's that will give you a pleasant long eye relief. OTOH, one single Barlow lens can be used with several of yours already existing EP's, providing different magnifications and thus avoiding the need to purchase other EP's.
  23. As Brantuk says, it's better to use less glass. no matter how good the quality and coatings of a Barlow lens, it will always take it's share of light. Years ago, before long-eye relief EP's came around, a barlow was very useful to allow you to use a longer focal lenght eyepiece, with it's natural longer eye relief, and getting a higher magnification. Nowadays, you can easily get short f.l. EP's that will give you a pleasant long eye relief. OTOH, one single Barlow lens can be used with several of yours already existing EP's, providing different magnifications and thus avoiding the need to purchase other EP's.
  24. It's not only 1 inch less and a bigger focal length. Going from a simple reflector to a SCT also means more glass and more absortion and reflections. Apart from the EP's that both need, in the reflector you have just 2 reflection surfaces. In the SCT you have those 2 plus one front glass plate and one diagonal in the way. Not mentioning a larger central obstruction... No matter how good the transmission and coatings are, there is always some light loss. Always. (needless to say... I'm a dob lover
  25. There's a small but very important flaw in yours premises: Bread doesn't always fall with butter side down! It's just more likely to happen that way. In fact, the probability of bread falling with butter side down is proportional to the value of the carpet. So to maximize the odds, you'd need to cover the side of the spaceship facing the mouvement's direction with a very expensive carpet. That will increase the budget a lot. And with such an expensive carpet on the wall, you better keep all those cats and cows away (or you can use some os those wifes if they volunteer to keep the carpet clean...). Anyway, you can't send all the cats because mine will stay here:D
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