Pentax PCF WP II 20x60

[skymacho2]

na polskim rynku w atrakcyjnej cenie jest dostępna lornetka Pentax PCF WP II 20x60. Pole widzenia kątowe 2.2 st., a odstęp źrenicy 21mm. Na cloudynights.com poświęcono jej sporo uwagi. Wg. Zarenskiego w rzeczywistości jest to lornetka 19x57, ma małe pole widzenia ale daje świetnej ostrości obraz. Poniżej więcej jego uwag:

 

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"The Pentax 20x60 has a 2.2° fov, actually measured 2.18.

The triangle of Vega, epsilon and zeta Lyra is just barely seen all at once.

 

62 arcsec nu Draco is easily seen everywhere.

21 arcsec (61 Oph) is seen out to 90-95% of fov

14.2 arcsec (100 Herc) is seen out to 80-85% of fov.

 

This is outer field sharpness rivaling the best binoculars, but do keep in mind this is the narrowest fov binocular of any I have ever seen."

 

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"A few more tests on these WP II 20x60s.

 

Resolution is pretty good, not in the top tier but comfortably better than the mean.

 

Off axis sharpness is among the best. I generally compare the usable fov measured to 600 arcseconds. The 20x60 is only 400 arcseconds at 95% out and has a usable fov right to the edge, giving it a usable fov wider than some 20x80s I’ve tested.

 

17mm of usable eye relief. Works best for me with eyecups turned out one notch.

 

Laser test shows good light beam transfer. Although one barrel had an optical axis more tilted than the other, the overall beam transfer was pretty good.

 

Aperture measured at 57mm. Magnification checks at about 19.5x to 19.8x.

 

Near close focus magnification is 20.5x.

 

Pincushion extremely low, among the least measured, may mean this binocular is a bit more difficult in most terrestrial observations as a lack of pincushion may translate to a greater rolling ball effect, (Although to my eyes, no rolling was seen)."

 

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na cloudynights mamy też recenzje tej lornetki:

http://www.cloudynights.com/item.php?item_id=227

http://www.cloudynights.com/item.php?item_id=226

i porównanie z Celestronem 20x80:

http://www.cloudynights.com/item.php?item_id=178

 

 

na optyczne.pl jest dostępny jej test:

http://www.optyczne.pl/21-Test_lornetki-Pe...20x60_V_WP.html

 

Widać, że na Zachodzie lornetka Pentax PCF 20x60 jest dość ceniona w zastosowaniach astronomicznych. W Polsce ma ona taniego konkurenta jakim jest rosyjski BPC Kronos 20x60 ale może ktoś jednak używa jej do astro ? Jeśli tak proszę o podzielenie się swoimi spostrzeżeniami.

Edytowane 21 Marca 2009 przez skymacho2