Helios stellar 11x80 Bins

[Hawksmoor]

Have had the above bins for a number of years. Never noticed before that the exit image on both eyepieces is clipped (rather than perfect circles). Views through the bins seem fine although not as bright as when first purchased.(I've put this down to my age rather than any short coming in the bins, in my 60's I don't suspect my eyes can hand a 7mm exit pupil). Should I be trying to adjust the binoculars? Is this something I could do (I noticed there are two screws that are accessible)? I'm no expert so thought I would seek advice before doing something with a screwdriver that I might quickly regret!

thanks in anticipation George (AKA Hawksmoor)

[Flying Eye]

Have had the above bins for a number of years. Never noticed before that the exit image on both eyepieces is clipped (rather than perfect circles). Views through the bins seem fine although not as bright as when first purchased.(I've put this down to my age rather than any short coming in the bins, in my 60's I don't suspect my eyes can hand a 7mm exit pupil). Should I be trying to adjust the binoculars? Is this something I could do (I noticed there are two screws that are accessible)? I'm no expert so thought I would seek advice before doing something with a screwdriver that I might quickly regret!

thanks in anticipation George (AKA Hawksmoor)

Assuming we are talking a sort of diamond shape, then I understand this points to undersize prisms being used (cost/corner cutting by manufacturer).

It all depends on how badly this affects you I suppose; My Oly's have this "feature", and I feel like there is something like an eyebrow, or part of my eyelid interfering very slightly at the edges of my field of view. It's worse/more noticed in day light than with astro use.

For my part given what I paid for them I can live with it, as replacing them at this price (£50) is not going to be easy, and probably not all that possible.

In my case it's a very slight dimming of the view at the very edges I have also found some stray image reflected outside of that. I do have to go to some considerable lengths to provoke this though! I've just today been developing a ploy by which I can take a photo of it, but I'm not quite done tweaking the system yet or I'd have happily posted an example. I'll do it once I can consistently get the right result, at which point it could become useful information.

Hope this makes it a little clearer, I don't think you can do anything about it.

[Hawksmoor]

Thanks Ian for your reply. I can't say I've really noticed an eyebrow effect whilst I'm looking through the binoculars. The exit pupil image however exhibits the eyebrow effect. I guess, because I'm getting old and with my iris being considerably less than the bins exit pupil of 7mm, my iris is probably acting as a stop and consequently I don't see it. Anyway I've decided to put my screwdriver away and leave well alone. Thanks once again. George

[Flying Eye]

I guess, because I'm getting old and with my iris being considerably less than the bins exit pupil of 7mm, my iris is probably acting as a stop and consequently I don't see it.

George, that strikes me as an excellent point.

Here is where I am getting my info from - LINK - a very helpful site that one.

What now bothers me is that I definitely have deteriorating eyesight, and I can't see this as being worse at night, which is what we might expect to happen.

I've developed my photo taking procedure about as far as I think I can for the moment, and now have one or two adequate images, I'll probably put together a new post showing them in the next day or two, I'll either post it here at SGL or supply a link if I post it elsewhere. I have some prior commitments, but a day or two might see me with a large enough time window for doing it.

[Hawksmoor]

Thanks for the link Ian

regards George

[Flying Eye]

I've had a quick bash at posting some images.

I set the link in this new thread