Anteres 50mm Right Angle Finder
About a month or so after buying my Orion 120mm refractor I quickly realized that one of its major shortcomings was the finder. While the supplied 6 x 30mm finder was of good quality, I was severely restricted as far as light collection and usability. The first problem was quite obvious, I live under mag. 3.0 – 3.5 skies and a 30mm finder was not going to allow me to find even moderately faint objects or stars. The other problem was not initially apparent but after one good nights worth of observing, the pain in my neck told the tale. When pointing the telescope anywhere moderately close to the zenith you were forced to not only kneel on the ground but also kink your neck in the most torturous of ways. This problem had to be solved.
So I went shopping for a new finder. To solve the first problem I quickly narrowed my selection down to only 50mm finders. I felt at this aperture I might begin to get more use from my finder even in my extremely light polluted area. I also figured that I needed at least a 45-degree and most likely a 90-degree finder. After doing some quick measurements I found that nothing less than a 90 degree finder would do. Within minutes I was searching online for reviews and prices.
After spending a few hours weighing my options I finally decided to purchase an 8 x 50mm model from Hands on Optics. I had dealt with them before so it was an easy choice. They have excellent customer service. I asked a few initial questions over email and received the response the same day. Specifically I purchased their black 8 x 50mm – 90 degree – erect/correct image finder for $100.00. I also purchased the Synta (Orion, Celestron) 50mm guide scope dovetail bracket for $29.99. The order arrived within five business days in excellent shape.
The product features an erect/correct image Amici prism. While a correct image was not one of my specific criteria it quickly became apparent to me that for the same price as the regular prism I could have the simplicity of the correct image. The scope is built like a tank. The tube is thick and the dew shield feels like it weighs a pound on its own. This actually works in my favor as it allows a much better balance point for my OTA. The supplied eyepiece is of what I believe to be a Kellner design with double crosshairs. It is fairly well constructed and lightly coated it also has its own focus ring. Lastly the lens has nice deep green coatings on it and was free from any scratches or chips.
Amazingly the first night I had my new finder the skies parted and the stars begged for my attention. I quickly mounted and adjusted the modified (more on this later) dovetail on my telescope and balanced the tube. Like I said earlier the weight of this finder helped bring the tube into a much more comfortable balance position. After I finished I took a second to admire my white 120mm refractor with a black 50mm finder – it looks like it means some business now.
Enough of that, time was becoming important as a wall of clouds was slowly sweeping in from the North. I quickly panned to the general area of the magnificent M42 and took a peek in the finder. With some quick adjustments I had the nebula in the center of the crosshairs. The view through the finder was just a bit better than my previous pair of 10x50mm binoculars; the nebula and surrounding star fields were just a tad bit brighter in the finder. With time quickly running out I swept the general region around Orion to see just how deep this finder would allow me to go. It shows the fainter stars and clusters much better than the old 6x 30mm model that I had but that is just what I was expecting. After swapping them out really quick I also noticed that the 50mm finder went quite a bit deeper than the 30mm finder, but this was also just as I was expecting.
As well as this finder works there were also a fair share of problems. Thankfully I was able to tackle most of them within hours of receiving the scope. The first problem was partially my fault. Instead of ordering the generic 50mm finder rings I went for the Synta dovetail bracket. I figured that since my telescope also used this nice arrangement that this would be the best way to go. Well I was wrong. I guess not all 50mm finders are built the same. The tube of the finder was just a bit too large to fit into one end of the ring. I solved this problem in ten minutes with a metal file.
The second problem however was not my fault; the crosshairs on the eyepiece would not be in focus when the eyepiece was focused. It seems that the designer had really overlooked a fairly major part of the scope. With the crosshairs out of focus this finder would be almost useless. But, after checking out the problem I realized that if I slid the eyepiece about a centimeter up from the bottom of the diagonal that both the eyepiece and the recticle would be clearly in focus. So far it has worked just fine.
Lastly the optics themselves suffer from a bit of edge of field aberrations. It really reminded me of looking through my old cheap 10 x 50mm binoculars. The outer 15 - 20% of the field is warped by coma and general blurriness. It is just more apparent because this scope was mounted and not hand held. If you can look past this the center of the field is very nice and sharp.
In order to sum everything up you basically get what you pay for. In this instance you get slightly more than you pay for. The construction is very good and the optics are above average in this world of cheap finders. For about $100.00 this has been a great purchase and I really doubt I would get much more from a more expensive model. Plus my neck is no longer sore after a long night of observing. On a scale of 10 this finder deserves about an 8.5. You must also consider the fact that the competing models are about 50 – 80% more expensive.
Submitted by Curt Irwin - firstname.lastname@example.org - Grand Rapids, MI