Saturday, June 25, 2005

Mini-Review: Orion Stratus™ Widefield 17mm vs. Orion Lanthanum Superwide™ 17mm

Eyepieces: Orion Stratus™ Widefield 17mm and Orion Lanthanum Superwide™ 17mm

Scope: Meade LX200 Classic 10", A-P 2" visual back/WO 2" Diagonal

Location: Mansfield Dam, Austin Texas

Skies: Very steady, but slight haze accentuating SE light dome. Polaris & 2 other Little Dipper stars visible.

Targets: M51 & M13

Observers: Myself, Mark, Andy (of, and Richard (of Austin Astronomy & Science, and admitted eyepiece snob)

Results: The most interesting result of our impromptu test was that all 4 of us agreed on what we were observing. Mark & Andy were the "control group," and compared the EPs blind, not knowing which they were viewing through, which IMO makes the results more valid.

We found that the 2 eyepieces were very similar in most respects. Although the Stratus is supposed to have a 3° wider aFoV, observing the edges of the view of M13 had the same stars lying along the field stop. The magnification may have varied enough between the 2 to mask any difference in the FOV, but none of us were able to discern between the 2.

Edge correction in both was excellent, with no significant degredation approaching the edges. Not terribly surprising in the f/10 LX200--further testing in a faster scope may reveal a difference.

Neither eyepiece showed any lateral color, but the targets did not include particularly bright objects off axis. The LVW has shown very slight lateral color on other objects, but wasn't observed this session.

Both eyepieces were sharp and bright, with pinpoint stars. (I'm particularly pleased with the collimation in this LX200.) The only difference we all noted was that the LVW showed more contrast, with a slightly darker sky background. The difference was subtle on the low-contrast M51, and slightly more noticeable on the brighter M13. We speculated that the difference could be due to polish, coatings or design, but did not attempt to quantify it. The contrast difference wasn't enough for Mark & Andy to comment on until prompted--"Which one shows more contrast?"--but they both agreed blindly that the LVW had the edge.

One difference that Richard & I agreed on concerned using the Stratus in the 2" diagonal. The 2" portion of the barrel is rather short, and the eyepiece didn't feel particularly secure in the diagonal. A non-issue in a 1.25" focuser or with the 1.25" adapter, but notable none the less.

Conclusion: Orion seems to have a winner here. For about half the price of the Lanthanum Superwide, the Stratus was very nearly equal, giving only the slightly lower contrast to the more expensive LVW. Richard and I think that unless you were comparing the 2 views side-by-side and looking for the difference, like we were, you'd not notice any difference. Richard feels like these are very nice eyepieces for their price point. Compared with the more expensive LVW, I agree. I'd purchase the Stratus and pocket the difference.