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nobody

02 Sep 2012 18:25



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@catalin dumitru:
In acest caz nu este nimic de explicat deoarece ai pornit de la o premiza gresita, hai sa-i zicem presupunere: "un 10X80 va oferi o imagine mai luminoasa decat cea naturala"
Un presupus binoclu de 10X80 iti va da o pupila de iesire de 8 mm.
Ce-i peste 7 mm se pierde, nu poate intra in ochi, oricat ai vrea de mult.

Totusi, exista asemenea binocluri militare, dar nu pentru ca ofera o luminozitate mai mare decat un 10x70, ci pentru ca asigura un confort vizual in cazul alinierii imperfecte a celor doua pupile (de iesire din binoclu, si de intrare la ochi) in conditii extreme. The exit pupils are 8mm, larger than any human being's pupils could possibly dilate even after a week in a cave. This means some light is wasted, but the advantage is that the view through the binoculars easy for your eyes to grasp and hold. This would have been helpful if you wanted to use the binoculars while your tank was bouncing across a field, but it also means that the 10x80s are exceptionally comfortable. There is no trick to viewing and even inexperienced users will find them easy and pleasurable to look through for a long time. 

@ursamajor:The telescopes recommended in this article are portable, easy to use and allow the novice to grow in the hobby. In a nutshell, they are the kind of scopes that get used. Many expert astronomers are using the same or similar telescopes. They know scopes that are easy to use get used, while the giant dinosaur-scopes languish in storage.

Telescope aperture: How Much Do You Need and How Much Can You Stand? 
Stanescu Octavian: dupa cum zici si tu, in anumite conditii, tot mai rar intalnite, se merita sa ai si un telescop mare. Doar ca unul mare nu poate sa-l inlocuiasca pe cel mic. Si nici invers.
Pentru DSO iti trebuie mai mult un cer fara poluare luminoasa decat o apertura enorma. Cred ca esti de acord cu asta. Iar daca tot te alegi cu un telescop mare, acesta trebuie sa fie si de calitate. Iar la cele comerciale ieftine ("recomandate" incepatorilor) calitatea nu este cel mai important criteriu ...