Flat mirror grade

[Okeydokey]

I took my bino's out this evening, having trapped a nerve in my neck.  I used the bathroom mirror on the garden table and was pleasantly surprised by the result.  I don't use a tripod for the bino's (7 x 42) but enjoyed some useful observations leaning with my elbows on the table.

I wouldn't mind buying a good quality mirror and doing this more routinely,  I can easily knock up a downward pointing table top bino mount.  Is there a system, standard or similar that grades flat mirrors, or can anyone recommend a supplier?

Many thanks

[Merlin66]

For large flat mirrors (of a size needed for bino's) - are usually only coated float glass - window quality. To get a suitable sized, 1/4 wave flat mirror would probably cost far more than the bino's did.......

[cantab]

To my understanding mirrors for this sort of viewing don't need major precision, because they're "before" any focusing optics, so you don't have all parts of the mirror reflecting light to a single point in the image. They do however need to be front-coated or you'll get double images.

[Charic]

Okeydokey.....Without distracting you from your DIY project, as the manufactured variants of binocular mirror reflectors cant be that cheap, have you thought of,  or tried a reclining sun lounger. This could offer more support for the neck, as your almost horizontal  or inlined to about 45° but the body/neck is aligned. The binoculars look very light, so not difficult to almost rest on the eyes? Just make sure the neck strap is in place, You may fall asleep.  A  large sleeping bag, so you can still wear your foot wear, keeps in the cosiness. My only concern would be the actual reflected image from the mirror project. That would be reversed, so Moon is upside down again? EDIT* As cantab mentions, the double image is a possibility unless the mirror is a front surface mirror. But first check your existing mirror.

[Merlin66]

A large front surface mirror used this way is prone to dewing up and collecting dust etc.......

Not the answer to a maidens prayer

[NEM]

The Jan 06 issue of Sky at Night magazine gave plans for a binocular viewer like this.  They mentioned this company http://www.vacuumcoatings.ltd.uk/Autocue%20and%20FS%20Mirrors.html as a source of front surface mirrors.

Noel