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Message: <blockquote data-quote="Kevin Purcell" data-source="post: 1269797" data-attributes="member: 68323">Day 2 tests: Ranking the binsAfter this I moved to a bench just south of the entrance to the Seattle Asian Art Museum in Volunteer park. This spot provides a series of targets looking westwards to view at a range of distances from 3m out to the top of the Space Needle 5km or so away including several flower beds and boxes (with blooms with colorful and detailed patterns) and trees (both illuminated and in shade). Plus a couple of man-made signs (black on white lettering for both resolution and CA testing).So I tried a series of tests and ranked the binoculars on each test.BrightnessLooking at a colorful flowerbed in the sun at 18m. In this case the Yosemite and the DX tied as about equally bright in bright light light.1. Leupold Yosemite 6x301. Celestron Ultima DX 8x323. Vortex Diamondback 8x424. Vortex Hurricane 8x285. Minolta Compact 8x25Sharpness/AcuityLooking at medium contrast (mauve/purple) flower petal details in a flowerbed in the sun at 18m. The DX was clearly the best in this case both sharper and large magnification than the Yosemite gave it an edge.1. Celestron Ultima DX 8x322. Leupold Yosemite 6x303. Vortex Diamondback 8x424. Vortex Hurricane 8x28(Shallow) Depth of FieldFocusing on the flower bed at 18m then looking down the light of sight to the Black Sun sculpture (the "Doughnut") at 45m and checking the focus on the edges of the sculpture and on the white spots of bird poop on the sculpture.1. Celestron Ultima DX 8x322. Leupold Yosemite 6x303. Minolta Compact 8x254. Vortex Hurricane 8x285. Vortex Diamondback 8x42ShakeLooking at the top of the Space Needle (at infinity) to check for amount of shake generated by me holding the bins. I think the Hurricane fared worse than the lighter Minolta Compact because I tend to grasp the Hurricane with a fingertip grip instead of wrapping my hands around them. The Yosemites win by virtue of their lower magnification. Another example of why I prefer the porro grip.1. Leupold Yosemite 6x302. Celestron Ultima DX 8x323. Vortex Diamondback 8x424. Minolta Compact 8x25 (6 oz reverse porros)5. Vortex Hurricane 8x28Sharpness (middle distance)Looking at a WA state license plate in bright light on the back of a car at 35m. I think the Yosemite loses out here because of it's lower magnification.1. Celestron Ultima DX 8x322. Vortex Diamondback 8x423. Leupold Yosemite 6x304. Vortex Hurricane 8x28Sharpness (infinity)Looking at a Space Needle though some heat haze. I think the Yosemite loses out here because of it's lower magnification. Diamondback and DX seemed about equal in this case (perhaps limited by the convection in the atmosphere). Yosemite again loses out because of it's lower magnification.1. Vortex Diamondback 8x42 1. Celestron Ultima DX 8x323. Leupold Yosemite 6x304. Vortex Hurricane 8x28Sharpness (close in and in shade)Looking at a conifer bush at 11m. The exterior is well lit by direct sun but there are "holes" in the bush that let you see the gnarly trunk in the shadows. Looking at the trunk for bark details.1. Vortex Diamondback 8x422. Leupold Yosemite 6x303. Celestron Ultima DX 8x324. Vortex Hurricane 8x28Focusing "Snap"Looking at a Space Needle though some heat haze. Vary the focus to see which image most "snaps" into focus. In truth I don't think any of these bins has a lot of snap. The form of snap I'm seeing seems to have more to do with focusing rate and the depth of field (or rather lack of it). Bins with the least DOF and fastest focus seem to snap most to me. But the DX certainly seems to be the least "snappy" with a slow focus rate and uncertainty (to me) when you've hit the correct focus.1. Minolta Compact 8x252. Vortex Hurricane 8x283. Leupold Yosemite 6x304. Vortex Diamondback 8x425. Celestron Ultima DX 8x32Viewing contrastsViewing a sunlit and shaded hedge at 40m. Looking at the shadows for maximum contrast and detail.1. Celestron Ultima DX 8x322. Leupold Yosemite 6x303. Vortex Diamondback 8x424. Vortex Hurricane 8x28Viewing a shaded tree bark next to the same strees sunlight bark at 45m. Looking at the bark in the shadows for maximum contrast and detail. In this case I couldn't see much difference between the Yosemite and the Diamondback.1. Celestron Ultima DX 8x322. Leupold Yosemite 6x302. Vortex Diamondback 8x424. Vortex Hurricane 8x28Distortions apparent during panningPanning across at a solid stand of everygreens at 50m range. Noting the effects of "rolling globe" distorition and other edge of field distortions. Ranking from best to worst (least to most). The two Vortex roofs are tied here with minimal effects visible. The DX the most clearly apparent distortion.1. Vortex Diamondback 8x421. Vortex Hurricane 8x283. Leupold Yosemite 6x304. Celestron Ultima DX 8x32Chromatic Aberation (on axis/just off axis)Looking at crows perched on the top of trees at 50m. These are small targets very close to the central axis. Not much CA noticed any any of these bins but some images looked slightly dirties than others. I noticed with these and other similar bins that placement of eye with the central axis o the binocular is critical for keeping CA down. If you place the eye off center you can see purple fringes on one side and yellow fringes on the other side of a crow like image. Moving the eye to the other side of axis reverse the fringe colors. The Yosemite and the DX tie for the least CA. 1. Leupold Yosemite 6x301. Celestron Ultima DX 8x323. Vortex Diamondback 8x424. Vortex Hurricane 8x28Apparent FOVHow large is the apparent field of view seen when wearing eyeglasses.1. Celestron Ultima DX 8x322. Vortex Diamondback 8x423. Vortex Hurricane 8x284. Leupold Yosemite 6x30Stray LightViewing solid stand of everygreens at 50m range with blue sky above. Looking in the dark tree image for "veiling glare" from stray light (that compromises the image contrast). From best to worst. The Yosemite and DX tied for best.1. Leupold Yosemite 6x301. Celestron Ultima DX 8x323. Vortex Diamondback 8x424. Vortex Hurricane 8x28Field stop sharpnessThis is a ranking of the sharpness of the field stop as seen wearing glasses. Leupold Yosemite 6x30 (sharp)Vortex Diamondback 8x42 (soft; can't see whole AFOV)Vortex Hurricane 8x28 (soft; can't see whole AFOV)Celestron Ultima DX 8x32  (soft; CA fringing; can't see whole AFOV)Focuser ActionHow does the focusing action feel. This is just the tactile feel (not the rate or focusing). I think for all the bins with more use the focuser friction reduced. With the Hurricane the effect was such that I was feeling that it was turning too easily.1. Minolta Compact 8x252. Leupold Yosemite 6x303. Celestron Ultima DX 8x324. Vortex Hurricane 8x285. Vortex Diamondback 8x42Hinge stiffnessIn order of most to least stiff.1. Celestron Ultima DX 8x32 (unpleasantly stiff)2. Vortex Diamondback 8x423. Leupold Yosemite 6x30 (just right)4. Vortex Hurricane 8x28 (too loose)Grip and balanceHow do the bins feel when you handle them raised to the eyes. I think I have a bias towards the porro bins for this.1. Leupold Yosemite 6x302. Celestron Ultima DX 8x323. Vortex Diamondback 8x424. Vortex Hurricane 8x28More tests (including night time tests) to come.EDIT: if you've not read it Holger Merlitz paper on the Rolling Ball effect and pincushion distortion you should. It's why all modern bins have some pincushion distortion and the amount varies by manufacturers (so bins have their own distortion signature).<a href="http://www.holgermerlitz.de/globe.pdf" target="_blank">http://www.holgermerlitz.de/globe.pdf</a></blockquote>

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