A small introduction. The exit pupil of an optical device is a small circle at the exit from the eyepiece in which all the light collected by the lens is concentrated. To calculate the size of the exit pupil, it is enough to divide the diameter of the binocular lens by increasing. For example, with 8×56 binoculars it is 7 mm, and with 10×25 binoculars – 2.5 mm. The larger the exit pupil, the brighter the image at dusk and at night. As a rule, for daytime observations, a pupil of about 3 mm is sufficient, and for astronomical observations, preferably from 4 mm and more. At night, the human pupil expands to 6-8 mm, so in binoculars usually the value of the exit pupil does not exceed 7 mm, otherwise the light at the exit of the eyepiece will go past the pupil. Binoculars, in which the exit pupil is 6-7 mm, are called PUPIL EQUAL. When this is achieved the maximum brightness of the image. If you compare 8×56 and 8×30 binoculars in the night sky, then the image brightness in binoculars 8×30 will be 3.5 times less, since with the same magnification the lens of 8×30 binoculars is 3.5 times smaller in area, and, accordingly, less light falls into the observer’s pupil.
For a long time I looked at the pupil equal binoculars. I was not impressed with the low-end models (Nikon Aculon 7×50, ZOMZ 7×50, Yukon Point 8×56), so for the time being I was using Nikon Sporter EX 8×42 binoculars. However, it was possible at a reasonable price to get used binoculars with DDoptics Nachtfalke Ergo 8×56 gen II roof glasses (hereinafter DDoptics 8×56). Initially, there was little information on this binocular, but after the purchase I found quite a few reviews of this binocular, produced under other brands. Apparently, the binoculars turned out successful, since it began to be sold immediately in various reincarnations. In general, I will not pull, proceed to the review.
Binoculars with a formula of 10×50 are among the most popular.Such binoculars are suitable for both terrestrial and astronomical observations.In my opinion, 10x is the limit for comfortable observation without using a tripod. “The Pentax Russia” company kindly provided me with an interesting Pentax SP 10×50 WP binoculars for testing.The binoculars are quite new, the announcement took place in January 2015.
Pentax SP 10×50 WP
Specifications are stated:
Binoculars with central focusing and “porro” prisms
2 elements in 1 group
3 elements in 2 groups (aspherical element declared)
Real front lens diameter
Field of view from 1000 m
Exit pupil diameter
Field of view
Diopter adjustment range
+/- 2 D
From 5.5 m to infinity
Retractable with fixation
Waterproof when immersed to a depth of 1 m (JIS protection class 6, is not suitable for use under water), nitrogen content of the housing.
“Tripod adapter N” (69553)
Fully multicoating of all optical elements. Hydrophobic lens coating.
The “Meade Russia” company has kindly provided me with the Meade 8×42 Rainforest Pro for review and testing. Meade is positioning this optical device as a universal binoculars for tourists, hunters, travelers. I myself am a fan of binoculars and have a small collection of 5 binoculars with an aperture of 26 to 100 mm. For me, binoculars are not just a land-eye, but also a tool for observing the night sky, especially if you cannot take a telescope with you. In addition, binoculars are an excellent companion for a telescope – first we study the area of interest with the binoculars, and then we point the telescope there and observe various objects. I consider binoculars with 8x magnification to be the most versatile, since the observations are not yet hampered by shaking hands and they can see quite a lot of objects in the sky – star clusters, as well as the brightest nebulae and galaxies.
Meade 8×42 Rainforest Pro
I have the following requirements for binoculars:
1) good image quality across the field (at least 2/3 point stars)
2) minimum field curvature (stars in focus from center to edge)
3) large eye relief for observation with glasses (at least 15 mm)
4) full coating of all surfaces (affects light transmission and glare)
5) small chromatism (does not interfere with astronomical observations, but catches the eye during daytime)
Well, let’s proceed to the review.
Packaging. Meade 8×42 Rainforest Pro binoculars comes in a carton box.The delivery set includes a carrying bag, a belt and a cleaning cloth.High quality, full multi-coated optical surfaces, Bak-4 prisms, water resistance, nitrogen filling and durable rubber-coated housing are claimed.Made binoculars in China. Binoculars are made on the roof-scheme (prism with a “roof”). The stereo base is the same as that of the interpupillary eye distance, but due to the “straight tubes” such binoculars are more compact than the analogous binoculars with Porro-prisms. Читать далее (Read more) > > >