Friday, April 07, 2006

Orion 13mm Stratus Review: Initial Impressions

Tonight it was relatively clear, but with a big gibbous moon (74%) and 2/5 seeing conditions, it was not the best of nights to test out a new eyepiece. However, I was in a procrastinating mood (I have two papers to finish writing this weekend) and the new eyepiece was begging to be used. So, I set up the LX200 out in the front yard and ran over a few objects to get a quick assessment.

First, I tried the moon. With it's 68 degree apparent field of view, the moon filled up the huge window of the eyepiece, its entire disc barely fitting into the field of view. What a view! The eyepiece revealed lovely surface detail, clearly displaying ravines, canyons, ridges, and inner crater detail to a quality which I hadn't seen before. The image seemed nice and sharp all the way to the edge of the field of view to me, so my initial impression was a big thumbs up.

Next, Saturn. Without a barlow, the planet appeared small but big enough to discern some detail (main ring shadow and Cassini's Division). With the barlow, the image looked much nicer, but the poor seeing conditions really made it hard to get any real impression of the eyepiece's field of view (I confirmed this but switching to my 9.7mm plossl). Under better conditions I think that this will be a real treat...

Finally, I attempted some basic star tests. All stars I viewed (Betelgeuse, Sirius, Pollux) were sharp and bright, very nice. I moved over to Castor and the eyepiece split the double star with great ease, and both Castor A and Castor B were very sharp and very nicely defined. I tried the same object with the barlow but, again, poor seeing conditions prevented a really good analysis.

I can't wait to test this eyepiece out on a nice clear, clean night. I really want to see how this does with M13, the great globular cluster in Hercules. Overall, given the circumstances, its performance was very good and I expect great things from it in the future.

No comments: