|Entry: Astronomy:Equipment Reviews:Misc Accessories:Mars Eye Red Dot Finder|
I have long wanted a unity-finder for use with my Fuji 16x70 binoculars. When using binoculars in a dark sky, it can be difficult to figure out just what you are looking at - thousands of stars, all looking pretty much the same =:O
After reading Tom Trusock’s Cloudy Nights comparison review at
I decided on the Mars Eye Red Dot Finder.
I purchased mine from Apogee. Around $20 with shipping, a heck of a deal IMO.
In summary, it is a compact and competent finder (much smaller than a Telrad), with a large main lens which projects a red or green dot against the sky –a small slider switch on the right side changes the colour. My unit came with a detachable dovetail base included in the price, which can be slid onto the unit, and tightened in place with two thumb-wheels.
A thumb-wheel at the rear allows vertical alignment. Another thumb-wheel along the right-hand side allows horizontal alignment. (These adjustments are quite stiff, although I suspect this stiffness can be adjusted.)
There is a rotary brightness control knob under the front, with an inbuilt on-off switch. (Also stiff)
1 - The dovetail base is not especially suitable for attaching to binoculars. Some have suggested mounting these finders with Velcro, but in my opinion this is not solid enough, given the stiffness of the various adjustments. So I drilled a hole in the vertical surface at the front of the dovetail base, and screwed it permanently onto a strip of 1-inch wide by one-eighth inch thick by 3 inches long aluminium stock. The lower end of this stock has a quarter-inch hole – to mount the finder, I place the lower end of this stock between my parallelogram mount and the binocs, pass the parallelogram’s mounting bolt through the hole in the stock, then tighten the attachment bolt. Doing this in the dark should be an Olympic event, as you need at least 3 hands - difficult to do, but it makes for a very solid mount. Once aligned, the finder *stays* aligned.
2 - The brightness control had an intermittent open-circuit, so I rewired the unit, bypassing the brightness control and switch, and made the red-green slider switch into an on-off switch, and used only the red light. (In my teen years I worked as a radio-TV tech, and I have a deep hatred for rheostats with inbuilt on-off switches). Anyway, the rewired finder works great – a flick of the slider switch turns on the red dot, and another flick turns it off. I installed a 10-ohm resistor in series with the red LED to reduce the brightness a little.
3 - Fogging up. The finder’s main lens is exposed to the night sky, so I expect to get some fogging. I will work on a solution to this. Also, when looking through the finder, my nose is at the binocular eyepiece level, so DO NOT BREATHE OUT. This indiscretion can lead to a 15-minute wait while the condensation evaporates from the eye lenses.
4 - Brightness. In my opinion this unit is not well suited to daytime use, the dot is simply not bright enough. This is hardly a criticism, as one seldom needs a finder in daylight. Another thing, the finder’s main lens is slightly “smoked”, reducing the brightness of whatever target you are aiming at.
Bob Bennett, Maple Vly, WA
Overall Rating: 9
Date: 08/18/2006 12:54:00 pm PST
Entry: Astronomy:Equipment Reviews:Binocular Reviews:Barska Blackhawk 8x32
8X32 Roof Prism – Blackhawk and Atlantic
In April 06 I ordered two pairs of Barska 8x32’s from binoculars.com, for my granddaughters to use on camping trips. One pair Blackhawk, the other Atlantic – these appear to be optically identical, but with slightly different styling. These were placed on back-order. At the same time i also bought a pair of 10x42 Blackhawks for myself, as temporary replacements for my Eagle Optics Ranger 10x42’s which had suffered what the insurance industry terms “a mysterious disappearance”, from my office.
Frankly, the 10x42’s did not suit my needs, so I returned them for a refund. Hence I had low expectations for the 8x32’s. Eventually these arrived, and I have been so pleasantly surprised that I bought a third pair of 8x32’s, for use by myself. I admit they are not as good as my long-gone Eagle Optics Rangers, but when used for grab-and-go birding, they do not fall short by all that much – see Pros ‘n Cons below. The ultimate validation came a few nights back, in our backyard; for years we have heard Swainson’s Thrushes during early summer, singing and calling on our property – great to listen to, but almost impossible to catch visually. Hearing one, in early dusk, I set out in earnest pursuit with the Barskas. Finally caught up with him, about 30’ up in a maple tree – these birds are well-camouflaged and move so quickly that they are a difficult target. I followed him all over several trees, singing and catching bugs, until he flew off. The barska’s provided quick and accurate focus adjustment, which helped a lot. For me, this experience alone justified the $62 price of admission – for this sort of use, these binocs are keepers. And if they get lost or stolen, I am out only $62. (The Rangers were $400)
Light-weight – good for kids.
“waterproof” – stay tuned, I will check for gradual fogging.
Easy to focus quickly.
No problems with image-merging.
No obvious collimation problems.
No noticeable false-colour issues – this was a surprise.
1. Not multi-coated – this produces some internal glare with strong incidental light on the field lenses.
2. Focus is not sharp across the complete FOV. I have seen this in other birding binocs, and in practice it matters little.
3. I currently have 3 pairs of the 8x32’s in my house, and I see some QC issues in the mechanical assembly
* there is a wide variation in the stiffness of the focusing and diopter mechanisms, and in the inter-pupillary adjustment.
* one pair has a slight but annoying slop in the main focus mechanism (although this is not nearly as bad as the slop in my Orion Vista 8x42’s). Another has a little slop in the diopter adjustment – not a show-stopper but mildly annoying.
Maply Vly, WA
Overall Rating: 8
Date: 06/16/2006 07:30:53 am PST
Entry: Astronomy:Equipment Reviews:Binocular Reviews:Eagle Optics Ranger 8x42
For a birder, there is a lot to like about the Eagle Optics Rangers. One year ago (mid 2004) i bought my wife a pair of the 8x42's. Coming from years of amateur astronomy I had little regard for roof-prism binoculars, regarding them as little more than an expensive affectation for yuppie birders - this opinion has been strengthened over the years, after asking various birders why they chose roofies, and getting a gaping mouth for an answer.
Anyway, these are roofies, and they rock! Strong points are
* rugged, rubber-clad
* sharp bright images on center
* accurate fast-focus
* incredible close-focus of about 5 feet - we can easily focus on nesting robins in the rafters on our verandah
* waterproof and fogproof
* captive lens caps at each end
* and did i mention rugged...
My wife sits her 8x42's on the dashboard of our van, while we hack up back-country fire roads in the Washington Cascades - occasionally there is a thud as they land on the floor. I have done this with other binocs and had to have them re-collimated. not so with the Rangers. They are frequently used in the rain, or left out at night on a campsite table where they are subject to heavy mountain dew, campfire ash, spilt beer etc - they have never yet leaked water or fogged up. If they get too dirty you can wash em without a worry. And i love the focus mechanism. It is so fast and slop-free you can capture your target in a second, just what is needed for birding at close range. The Rangers simply get out of the way and let you do your birding thing.
Optically i have noticed some minor imperfections. There is some pincushion effect - if you get sea-sick do not pan too fast! Also the sharpness of view starts to deteriorate slightly at about 70degrees off center - this is largely irrelevant for birding as you always keep the image in the center. And there is slight colour fringing on very bright objects. This all sounds worse than it is, possibly artifacts of the roof-prism design. Anyway they have no effect on the instrument's suitability for birding - i simply point these things out because i have noticed them.
I was so impressed with my wife's 8x42's that when it came time to replace my own birding binocs i chose the Ranger 10X42's - these look like another winner, with very similar characteristics to the 8x42's.
In summary, although i would probably not use these for astronomy, because that is not their purpose, they excell for birding - i believe you would have to spend 2 to 3-times the money to get anything noticeably better.
Maple Valley, WA
05/01/06:- A follow-up to the above comments... my wife and i finally had two pairs of Rangers, one for each of us, both used for birding. Sadly, my own pair, 10x42's (v.similar to the 8x42's) grew legs. I assume they were stolen, from my workplace - lesson: dont take good stuff to work. So... lacking the funds to replace them, i decided to order a pair of cheap 10x42's ($77, chinese, will not mention the brand) as a temporary replacement for the Rangers. It is unfair to heap dirt on cheap optics, after all "'ya gets what ya pays for", but i add the following to emphasize what the Rangers give you for your money.
1 - the Rangers make it easy to get a fast and dead-accurate focus. The cheapies take so long to focus that any healthy bird can be a mile away before i get both eyes focussed.
2 - the Rangers are sharp across most of the field. The cheapies are sharp across about 30%, the rest is dismal.
3 - the Rangers have excellent coatings. when looking at the field lenses in sunlight, i can see the reflection of a dim sun in a dark background. In the cheapies i can LOTS of bright suns in a bright background.
So... am hoping for another nice bonus check, for ta-da, another pair of Rangers.
Overall Rating: 9
Date: 05/11/2006 07:25:09 am PST
Entry: Astronomy:Equipment Reviews:Misc Accessories:Orion Lasermate Deluxe
I bought the Lasermate Deluxe to make collimation easier on my two reflectors. The idea is, with the Lasermate in the focuser you adjust the secondary mirror until the red dot strikes the centre of the primary. Then go to the primary end - if your scope is anywhere near collimated you should see the red dot reflected somewhere on the 45degree bevelled surface in the centre of the Lasermate tube. Then, while at the primary end, adjust the primary knobs until the dot "disappears" into the hole in the centre of the bevel. At this point the laser beam is reflecting right back up the light path to where it originated. In theory the scope is now collimated.
A brilliant gadget...
My reflectors use JMI DX3 focusers, which i regard as well-machined devices. Here's the rub... in either of these focusers the fit of the Lasermate is so sloppy that after i tighten the set-screw the device "flops" to a different (non-orthogonal) position within the drawtube, and the red dot no longer hits the middle of the primary. It flops around way more than a normal eyepiece does in these focusers, and it happens regardless of how much i tighten the set-screw. The problem is exacerbated by the top-heavy design of the lasermate. So, in my 10" Starfinder i use my right hand to hold the lasermate perfectly orthogonal in the focuser while i reach under the primary with my left hand and adjust its knobs.
Not so easy with my 17.5", i would need 6 foot arms. So i use my Helix Collimator in this scope.
I mentioned the problem to Orion's technical support - i was told it was designed under-sized to allow for use in a variety of focusers, and i should try wrapping electrical tape around it to get a tighter fit. Nice try, but i'm not buying it, i can't imagine any decent quality scope having a focuser so under-sized that the Lasermate would fit snugly - it would not be able to accept regular eyepieces such as TV, UO etc. And i dont like using plastic tape as a shim.
I am keeping the Lasermate for use in my Starfinder, but the fit is too sloppy to achieve its full potentital in larger scopes.
Bob Bennett, Maple Vly, WA
Overall Rating: 7
Date: 10/29/2004 06:28:20 am PST
Entry: Astronomy:Equipment Reviews:Eyepiece Reviews:Harry Siebert 2" 36mm Observatory Class
In search of a 2-inch wide-field EP in the 30-35mm range for my 17.5-inch f/5 truss scope, i called Harry to see if he could help (the megabuck megaweight jobs are not a consideration for me)
On his advice I decided to purchase one of the new Siebert 36mm Observatory EP's. This EP looks good, weighs well under one pound, has an approx 1.5-inch eye lens, a set-screw recess, and comes in one of Harry's neat belt-pouches. It also has Harry's incredible internal blackening - man it is *black*, way more so than my TV/UO/Celestron EP's.
He also supplied a press-fit eyecup to keep eyelash crud off the eye-lens - not sure if this comes standard.
Performance-wise i am very pleased - this eyepiece is a keeper. Stars are in focus across the field (70deg I think), it is not fussy regarding eye-position, and has good eye-relief without blackout. It is very easy to focus, unlike some EP's which require the focus to be 'spot on'. At f/5 it performs way better than my UO 32mm Koenig (too much black-out, too fussy re eye-position, and too many seagulls). It is also more user-friendly than my 40mm Axiom, due to smaller size and less out-travel.
In all this looks like being a great general purpose EP for a big f/5 scope.
I do not have any 2-inch Nagler/Panoptics to A-B it with, but based on reviews and comments i have seen on the web i have no reason to believe they would perform noticably better than the Siebert.
As a combination of fine performance and reasonable price i give this baby a 10.
Bob Bennett, Maple Vly WA
Overall Rating: 10
Date: 12/04/2002 06:13:10 am PST