Product Review: A Not So Good Report on the Olympus EXPS I 10 x 42. (1 Viewer)

[Dipperdapper]

Here we are: dioptre ring set to max positive travel


No sign of any flex or wobble in the bridge; very solidly built. Just tested under the stars; viewing through the binocular turned upside down flips the aberrations to the right-hand side of the image, just like the photo showed. It's possible to improve the edge of field appearance of the stars to a small extent but not entirely.

 

[Binastro]

The two 10x42 Olympus binoculars have close serial numbers so may be from the same batch.
There may be a problem with one batch or more generally.

Out of focus star images may indicate whether the problem is related to the collimation procedure.

The problem could be due to tilting elements, even wedge or a combination of errors.

It seems that some of these low to medium price optics don't have a grinding phase. Just moulded or pressed glass.
Then high speed polishing is suspect compared to older slower methods.
Even with older methods with bulk polishing, the centre blanks are better polished than the outside blanks.

Then there is the important issue of tolerances.
It seems that with modern optics, especially Chinese, the tolerances are lax.
It may be the first binocular was outside tolerance, the second just inside.

Michael Woodford's very brave action revealing the Olympus scandal where six executives had to pay half a billion dollars in compensation means Olympus has had serious problems even surviving.
This may not be the only case of a Japanese optical firm being suspect.

It is upsetting when new binoculars have faults.
With these Olympus binoculars it is possible that 95 users out of a hundred would not notice the problem.

I have had an almost identical problem with a highly regarded Vivitar Series one 70-210 zoom lens.
These lenses were better optically than Nikon, Canon or Minolta similar zoom lenses at that time. Maybe 1970s.
I sent the lens with slides showing the problem to Vivitar.
They put three similar lenses on their excellent test bench and sent me the best one as replacement.
It was excellent.

Besides the awful Pentax 20x60 I have a terrible Pentax 8x25 that the so called expert assured me would be better than a fabulous old Pentax 8x25 that unfortunately has fungus inside.

Testing, testing, testing is the answer.

Regards,
B.

 

[henry link]

Neil,

Would you agree that the last two photos fail to show any area of particularly poor sharpness on the left side compared to the rest of the FOV edge?

What I see is not what I expected to see. I thought the soft area would either rotate with the eyepiece (indicating the problem is in the eyepiece cylinder) or remain in place (indicating a problem somewhere in front of the eyepiece). Instead the problem seems to be gone in the last two photos!

There is obvious lateral misalignment between the phone camera and the binocular eyepiece in all the photos, but I suppose the last two could have less misalignment from tilt than the others. That might explain the tilted focus in the earlier photos, but not your visual impressions, so now I'm at a loss. I'll be interested to see what you can come up with.

Henry

 

[Dipperdapper]

Evening Henry,

Yes I do agree that when the dioptre ring was extended to the extreme of travel in both directions, the images did improve. Like you, I have no explanation for that.

I have taken similar images on the same target with a much better binocular that I'll be reporting on soon. Those images show very well corrected images nearly all the way to the edges. Camera misalignment is a possibility for some images, but not for all.

However, as you kindly mentioned, I saw and reported these aberrations with my own eyes, appearing on the same side for both units, both during the day and while star testing at night, so my verdict remains the same.

Disappointing.

Best avoided.

Kind regards,

Neil.