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Collins I3 Eyepiece

Cloudy Nights I32

Collins I3 Eyepiece

by Jeff Lipsman (Jeff@Dataflight.com)

I3 Piece First Light

June 2000. Los Angeles, CA USA. I've been giant binocular viewing for several years. I purchased my first telescope in the past six months. I now have a Tele Vue Pronto, a Tele Vue 101, and a back ordered Mak. I live in Los Angeles and view primarily from my home in the city. I try to attend the monthly Los Angeles Astronomical Society's dark sky parties at Mt. Pinos. I became interested in the Collins I3 Piece as a tool to use in Los Angeles' light pollution.

The I3 Piece eyepiece is a light amplifier built into a 15mm or 25mm eyepiece. It magnifies the incoming light so that you can see dimmer objects. According to the manufacturer, Collins Electro Optics , it produces an effective 2.5x to 4x gain in your telescope's aperture. It is battery operated. There are no external wires, monitors, or video cameras. You look into the eyepiece and view a light amplified image of the sky. The view is through a miniature monitor behind a focus lens.

I used the I3 Piece with the 1.25" adapter. It required a 2x Barlow to come to focus in my Tele Vue 101. The 2" model does not require a Barlow on the Tele Vue, but the manufacturer was out of the 2" model when I ordered. I should have the 2" adapter later this week.

The image is green. This may seem odd or objectionable, but it is not. You get used to it and forget about it very quickly. There is some static visible in the background of the Barlowed image, but it isn't too bad. I removed the 2"-1.25" adapter and physically held the eyepiece up to the 2" diagonal without the Barlow. The image steadied, revealing a nearly static-free green/yellow background and solid, sharp stars.

How well did it work? On Friday, June 2, I viewed from my backyard in Los Angeles using digital setting circles to put me on target. Megrez in the Big Dipper, magnitude 3.31, is clearly visible with averted vision: In other words, a typical night in Los Angeles. When the computer tells me I'm on M13 and I look through the Starbeam finder to verify, I see only white sky. There are no stars visible in M13's neighborhood. The unamplified wide-angle lens I use to center M13 shows the star cluster faint and fuzzy. Switching to the I3 makes the cluster pop. It looks like every star is resolved in brilliant sharp white (ok, green) focus. The center is a snowball, surrounded by pinpoint stars that orbit the cluster. My wife takes a look and says, "Now this [my astronomy junk] all makes sense. It's beautiful." Star clusters are awesome through the I3, even under the dismal light pollution of Los Angeles.

I turned to M92, M5, and M57. The star clusters M92 and M5 are awesome. The Ring Nebula, M57, is amplified and visible, it even seems to have some three-dimensional depth. It appears to curve inside the ring, presenting a concave face through the I3. But it is a small object in the Barlowed 25mm lens and I want to see more. Magnification is 43x through the TV 101. Barlowing up to a higher magnification creates static. Small distant objects look fine, but they need a longer focal length telescope to magnify them. Barlows above 2x do not appear to be appropriate tools. I did not try the 12mm version. That may be better than a Barlow. It would be worth looking into.

Surprisingly, the I3 works with binary stars. I was able to split the double-double with the 25mm lens. By split I mean that I could see that the two double stars were double bulges. They didn't actually split cleanly at that low magnification, but they showed distinctly as doubles. Epsilon Lyrae was the only binary I tried.

The next Saturday I took the I3 Piece to the Los Angeles Astronomical Society dark site star party. It was possible to find dimmer objects to view under the very clear skies. The Sombrero Galaxy, M104, showed brighter through the I3 than without amplification. The center bulge was particularly bright, but there was less amplification in the arms than I expected. According to the product's literature, the unit amplifies better in the infrared than the blue side of the spectrum. Like our eyes, it simply works better with some objects (or portions of some objects) than others. The view wasn't bad, but after viewing star clusters I was hoping for more. I wanted a closer look. Bright and big is better than bright and small. As with M57 I wanted more magnification. We doubled up on Barlows to get 6x. The image was certainly larger and it appeared brighter than an unaided Tele Vue 101, but the video static was terrible. I had Barlowed over the line.

Word seemed to travel fast at the star party. When you hear your neighbor's constantly saying, "Oh my God!," you get curious. People lined up to take a view and almost without exception they all looked, dropped their jaws, and repeated, "Oh my God!" It is hard to prepare for the awesome views of globular star clusters that the I3 Piece presents. Even the Binocular-People asked, "How much is that thing?"

The I3 Piece isn't cheap. It has a suggested retail of $1,995. However when combined with digital setting circles it allows city dwellers to take their scopes out of the closet and actually give them some use just about any time they want. That's why I bought it. It works, and yes I'd buy it again.

The I3 Piece probably isn't for you if you have a large aperture telescope and dark skies. If you live in a light polluted area and want to use your scope, you should certainly consider the Collins I3 Piece. It will keep you awake at night. It's not bad under dark skies either. I can't wait to try it with my back ordered Mak.

FYI, I have no affiliation with Collins Electro Optics whatsoever.


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