Mirror mount

[Duke2k]

I have a pair of 15x70 binoculars but due to neck problems I am struggling to use them even when tripod mounted.

I am thinking of making a mirror mount but I don't know if they are any good?

Can someone please advise me on which mirror I need, size and thickness, fixing method etc.?

Do they suffer from dew problems in the UK and if so is there an effective way around this?

If anyone could advise me on this it will be very much appreciated.

Thanks

 

[Peter Drew]

I've made myself a mirror mount for a 102mm binoscope, they are brilliant in use, particularly if you have neck problems. They produce upright, laterally reversed images and are much steadier than bracket mounted binoculars on tripods. You need a first surface mirror, a bathroom mirror won't do, it also needs to be of reasonable optical quality for good results. Vacuum Coatings Ltd offer such items in various sizes, the thicker the better. You need one wide enough to well cover the width of the binocular X 1.414 major axis, think rectangular Newtonian diagonal.  You can pivot the whole thing on a pan and tilt head or better still have an adjustable mirror which leaves a binocular at a fixed angle. I rest my mirror on a felt pad which itself has an aluminium plate backing. Finding things is entertaining, the view moves twice the distance that the mirror does so it is a challenge to find things but once you do the view is wonderful. If you Google "binocular mirror mounts" you should be able to access any amount of potential designs.     

[Stargazer McCabe]

@Duke2k

There’s not really much to add to what Peter said. Other than I have a front surface precision mirror sat at home that I was going to use to make my own Mirror Mount for my 16x70s. I had it made by a specialist company in North London. 

In the end I didn’t build the Mirror Mount as I also bought a bigger pair of binoculars, justifying the purchase of a P-Mount. 

I’m away until Sunday morning. But if you’re interested I’d happily send you details of who made it, size and i’m sure we could agree a price to get it out of my way if it can help you. I think I only paid £45 or thereabouts for it in the first place...

PM me if interested 

[Peter Drew]

A couple of images showing a fixed binocular with adjustable mirror.

[Duke2k]

Thanks for the replies guys. I like the look of your mount Peter, do you have problems with dew when using it?

[Peter Drew]

Not as yet. I have a felt lined cover that I place on it when not viewing. It mists over when brought back inside as with most things. 

[Merlin]

I'm fortunate to have a high precision ex-MoD military mirror on my homemade mrror-mount, bought for a song on a flea-market years ago. The tilting mirror is used with binoculars ranging from 8X40 to 25X70, but it can take much higher magnifications, as I found out when I directed a small refractor at it with a magnification of X70 and saw details on Mars.

A problem with making a mirror-mount is obtaining a suitable optically-worked mirror that won't produce smeared ( astigmatic ) images at the most acute angles of the mirror. Having made four mirror-mounts, it's been my experience that a piece of   unworked, surface-aluminised, plate glass is good for magnifications up to about X12.

I purchased an unworked plate glass mirror  from www.scientificmirrors.co.uk for £18,  and it's okay for the lowest magnifications. I then purchased a mirror from the same firm that was described as being "optically worked" at £60, but the performance was frankly disappointing and didn't seem to be any different from the unworked mirror when used with the 20X60 TENTO's: at the extremes, star images were smeared.

I feel very fortunate to have the high-precision MoD mirror and for just £3!

 

 

 

[Merlin]

Peter Drew said that his mirror-mount gives laterally-reversed, upright, images. This seems odd. My mirror-mounts give laterally-correct, inverted, images. Maybe the laws of physics vary in different parts of the country ( chuckle ).