Maxvision 34mm 68° comparo

[Ben the Ignorant]

First Light Optics had a 34mm/68° Maxvision demo eyepiece that caught my eye, and would ideally complement an 80mm f/7 semi-apo on its way to my telescope-filled home. After a few days of scanning competitors and pondering the need, I asked a friend who uses PayPal to order it for me, quick, quick, before someone else (you?) could snatch it. That was Saturday the 18. I received it today, 22nd of November with no problems.

I immediately painted the nosepiece with blackboard super-matte liquor, like I routinely do. Eventhough the paint is still shiny wet, you can see how it's already less reflective than the factory grey I left for comparison. The field stop being several millimeters from the lens, I could blacken it, too. Before the paint was dry I rubbed a wet toothpick aound the inner edge of the stop to pick up the paint, or it would leave unevenness. This left the field stop impeccably sharp, seeing it magnified from the other side is a perfect check.

Then came the green laser test. How dark is the coating, how does the glass diffuse light, how well is the - inaccessible - inside blackened? All features are very good, but you wouldn't believe it from the pic, my phone camera is oversensitive to green light, it seems. Plus, other reflections also look by far brighter than to the eye. I hoped the photo would show how good the eyepiece is, but instead I insert it as a reminder that photos and reality can differ a lot, remember this when you see pics in reviews or elsewhere.

The next image informs a bit better thanks to the side-by-side view, but again the differences easily picked up by the eye are almost levelled by the contrast-robbing camera.

If you look very carefully, the best is the cheap Plössl in the middle thanks to only four air-to-glass surfaces, and a blackening of the inside, spacers, lens edges and all, with blackboard paint, a treatment possible only with simple, non-sealed eyepieces. Second is the Maxvision (bottom right), third is the 30mm Aero (top right), fourth: Explore 24mm/68° (top left), last: Meade 24mm/82°.

Now the real comparo, done between three 68° candidates, my new Maxvision 34 (2") and a Sky-Watcher Aero 30 (2"), followed by that proven and popular Explore 24 (1.25"). Testing is done with the only 2-inch-focuser scopes I own: an 80mm f/6 triplet and an f/5 dob. Aldebaran and the Hyades were well placed to make the test convenient, nice group of bright and faintish stars. First I placed Aldebaran at the edge of the field to judge astigmatism, then compared other features which I will rate and describe one by one.

Apo:

Edge sharpness:

Gold: Maxvision 34. Star is small and very nearly round, surprising because the 34 picks up the largest, most aberrated part of the triplet's field.

Silver: Explore 24. Star is small, only slightly astigmatic.

Bronze: Aero 30. Star is astigmatic but still tight for a 1st-magnitude beacon.

 

Lateral color:

Invisible in all eyepieces with orange Aldebaran, so I switched to a remote parking lot mercury lamp.

Gold: Maxvision 34. No fringing to speak of, lamp maybe very slightly yellower than at the center, other colors might be defocused but the halo is too faint to see against the strong light?

Silver: Explore 24. Bluish/violet fringing, very minor, lamp is still sharp and detailed.

Bronze: Aero 30. Broader bluish/violet fringe, a little more blurring.

 

Field curvature:

Measured by the amound of refocusing between center and edge.

Gold: Maxvision 34.

Silver: Explore 24, difference with Maxvision is extremely small, might be a tie.

Bronze: Aero 30: seems it is close to its limit at f/6

 

Distortion:

All have crescent distortion, I have never seen barrel distortion in telescopes and binoculars.

Gold: Aero 30, would be a good astro/terrestrial ocular.

Silver: Maxvision 34, distortion is moderate, not shocking like in 82° and 100° eyepieces.

Bronze: Explore 24, strong bending of lines, but helps a lot with edge sharpness and overall sharpness.

 

Resolution:

Perceived resolution depends on magnification, but it is not equal in the three items tested here; 3 focal lengths. Kinda subjective.

Gold: Explore 24, no contest, color fidelity is remarkable.

Silver: Maxvision 34, might be a tie with Explore, hard to say with change in image size.

Bronze: Aero 30, last but still very good remembering the dismal 24 Hyperion.

 

Faint stars:

Influenced by change in magnification and exit pupil, which is a little too big for my eye at f/6 with the 34.

Gold: Explore 24.

Silver: Aero 30. Could be a tie with Maxvision.

Bronze: Maxvision 34, lowest power, very nearly a tie with Aero, could mean the Maxvision is really better since its pupil is fatter. Would require a dark sky to split them, but this night was too good to not immediately exploit it from home (within a city). Strange unusual mix of great transparency and strong wind, superb nights are usually quiet.

 

Daytime/terrestrial:

Gold: Maxvision 34, superb eye comfort, no major aberration, chromatic fringes are green/magenta, narrow but rather dense colors.

Silver: Aero 30. Shapes are well maintained, chromatic fringes are yellow/violet, broader than Maxvision but paler.

Bronze: Explore 24. Most distorted shapes, chromatic fringes same as Maxvision.

 

Ghosting/flaring:

Assessed by aiming next to a street lamp 30 meters away, and slowly bringing it to the field of view. All three units showed a broad diffuse halo when the lamp approached the field stop, however no arcs or flares were present while the lamp was outside the view. Could be my black paint job helps.

Gold: Maxvision 34. Moving the lamp from the edge to the center kept the halo nearly the same, very broad and pale.

Silver: Aero 30. Halo was not as broad, and a little brighter.

Bronze: Explore 24. Halo was more compact and brighter, plus a very small and faint flare danced in the middle of the image. I don't recall seeing this with the Moon or bright planets, street lamp test is harsh. 

 

Overall optical pleasure:

Gold: Maxvision 34. Very accessible eyelens, rubber cup not too broad, not too narrow, comfort makes the field look larger, eye relief is good but presence of the image is felt more than mere distance from the eyepiece. I paid 90€ for this!

Silver: Explore 24. Very sharp over the whole field, good comfort, good presence.

Bronze: Aero 30. No major weakness, no disappointment, but less razor-sharpness and stunning presence than others.

 

Overall convenience:

Gold: Aero 30. Lightest, most ergonomic, least costly, very smooth and noise-free mobile eyecup, no balance problem, well-shaped conical ridge around eyelens.

Silver: Explore 24. Excellent in nearly all respects but requires 1.25" adapter. Waterproof and washable.

Bronze: Maxvision. 780 grams! Fat! Balance issue for small scopes. Sliding eyecup present but not needed.

 

300mm F/5 dob:

This comparo will be shorter and specific to a steeper f:ratio; Meade 24mm/82° included instead of Explore 24/68 because it is my dob's default eyepiece. I fully expected a steep drop in edge sharpness but not much change, really. Testing done on Beta Tauri, a brightish white star, and two less luminous neighbors, all placed right against the field stop.

Coma:

Gold: Maxvision34. Coma not discernible through turbulence. Star is a bit hairy but roundish and tight. Seems the eyepiece matches the scope's field curvature very well, or that it has coma-reducing feature? Tightness is remarkable. 7mm exit pupil but my personal limit is 5mm.

Silver: Aero 30. Same but a little lateral color and astigmatism show up. 6mm exit pupil.

Bronze: Because of the larger field, the Meade 82° has more lateral color, but scope's coma is probably drowned in slight eyepiece astigmatism. 5mm pupil.

 

Other aberrations:

No meaningful change relative to the f/6 apo.

 

Very promising for the f/7 scope I'm waiting for, a semi-apo I will try to salvage from mold and neglect.

[Ricochet]

8 hours ago, Ben the Ignorant said:

how well is the - inaccessible - inside blackened?

Technically, it is accessible. The Maxvision/Meade SWA is not sealed and the lens/spacer set is just held in place by the screw in nosepiece.

[Ben the Ignorant]

Okay, but opening an expensive six-element eyepiece without letting any dust in is close to impossible, and cleaning it risks leaving other impurities from the cleaning tool. I did it with a mid-price, good-but-not-great Antares 25mm/70° (and found out it had six lenses, not five as an outdated ad stated), that carried little risk. The purpose was to shim the chassis so the lenses would no longer play inside. The improved centering made it sharper.

But seeing the purity of the Maxvision glass and coating, and the serious darkening inside, I don't want to take any chance. The lenses are so large it's easy to see that, and the focal length being very long, the image of the inside is not deformed much. The Maxvision has two minuscule dust specks inside, yes! They offend me a thousand times less than the two thousand dust specks floating in the air through which I observe.

So I will leave my Maxvision alone.

[Ruud]

Wow, Ben. That's a very informative comparison.

I know the 34 mm Maxvision 68° well and love it a great deal. You've described it well. With 14.7x magnification in my 4" f/5 refractor, it gave me excellent views of the lunar eclipse of a few years back with plenty of stars around the Moon's disk. The view was magnificent.

I have the 20, 24 and 28 mm as well. They were a true bargain. (The 34 mm cost €119. Now that they are getting rarer the price has gone up to €135. Still very good value!)

Thanks