sky windows and binoculars

The place to discuss telescopes, binoculars, CCDs and other equipment

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thomasfn
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sky windows and binoculars

Post by thomasfn »

I was wondering if anyone had used skywindows and binoculars before and what the advantages/disadvantages were over a telescope.
thanks guys.
skywatcher skymax-90+EQ1,strathspey 15x70 bins.
Earthshine
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Post by Earthshine »

By skywindows, I assume you mean a skylight in the roof of a house.

I use bins a lot. Well worth using for general views of the night sky.

The best sizes generally are:

(Mag x Aperture)
10 x 50
15 x 70
20 x 80
20 x 100
25 x 100

I have a pair of 15 x 70's from Strathspey and they have Bak-4 coatings (advised for astronomy). These will set you back between £70-£100.

The higher mag's will cost over £125, upwards to about £500+. Some premium quality bins can cost £1000.

Best to invest in a good tripod too.
thomasfn
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Post by thomasfn »

by sky window i mean this http://www.tricomachine.com/skywindow/ just wondered what ppl think of em
Last edited by thomasfn on Tue Oct 28, 2008 9:33 pm, edited 1 time in total.
skywatcher skymax-90+EQ1,strathspey 15x70 bins.
Earthshine
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Post by Earthshine »

This looks quite good. I don't think they are available in the UK.

If its reasonably cheap, it might be a good idea to invest in one, but it really looks like a comfort thing. Offset the cost of one against a good tripod, which if positioned correctly can still give comfortable viewing.
mike a feist
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Post by mike a feist »

I would imagine that the laterally inverted (mirror) image would be very frustrating especially with the large fov of binoculars. However obtaining a front aluminised (silvered) flat mirror should not be too difficult and the rest would be a matter of a bit of DIY. I had never heard this device being called that either...I guess it is the trade name. maf
brian livesey
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Post by brian livesey »

I've built several "SkyMirror" assemblies (two for myself with different-sized mirrors and one for Norman Crompton at his Pendle Valley Observatory)) on the kitchen table, so to speak, and can recommend this method of binocular viewing.
It's easy to knock up a "Skymirror" with bits of wood and some screws. Cheap first-surface mirrors can be obtained at:
http://www.scientificmirrors.co.uk .
Mike makes the common mistake of thinking that the field is laterally reversed in a "SkyMirror"; the image is, in fact, upside-down as in an astronomical telescope. Personally, this doesn't bother me, it's a small price to pay for the rock steadiness of the image and the comfort of the viewing position.
I made a platform for my "SkyMirrors" that I can poke out of upstairs windows with me on the inside out of the wind.
brian
nealeh
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sky windows and binoculars

Post by nealeh »

I have the ScopeTeknix Mount that I use with my Celestron 9 x 63. It really is a great device - worth asking if they are expecting more stock.
Cheers,
--
Neale
Insanity is hereditary, you get it from your children
mike a feist
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Post by mike a feist »

Mike makes the common mistake of thinking that the field is laterally reversed in a "SkyMirror"; the image is, in fact, upside-down as in an astronomical telescope.
Just done an experiment with a mirror and binoculars. Yes the left and right are not reversed but the picture is upsidedown. The sign that I am looking at it upsidedown but even by rotating it in my head the words are back to front though.
With the usual astro-scope - refractor (less stardiagonal) the image is not just upsidedown but lateral transposed too and so you can turn your starmap and moonmap through 180 degrees and it fits the sky. I quite undestand that many modern scopes use diagonals which have the effect of producing mirror images and at least one moon atlas gives both real and transposed maps.
So I agree that in the image left is left and right is right but essentially the image is back to front...the word "Adult" on the sign when imaginarily rotated says "tludA". maf
brian livesey
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Post by brian livesey »

Thanks for that, Mike. Absence of a "correct" orientation doesn't bother me, I can see more in the rock-steady "SkyMirror" despite a slight loss of light absorbed/scattered by the reflecting surface.
I'd like to add that a laser pen can be used as a finder with a "SkyMirror", which is handy for higher-powered binoculars.
The pen should be fixed so that it points down onto the mirror with the laser beam bouncing off the mirror and up into the sky at the object we wish to centre in the binoculars. Of course, it's necessary first to ensure that the laser pen is lined up with the binocular view. We can do this by, first, centering the Moon, a planet or bright star in the binocular field, then, turning on the laser to see if the beam bouncing off the mirror points at the target object; we can adjust the pen until it does.
brian
Malcolm Zack
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skywindow

Post by Malcolm Zack »

have not used one so dont have a view. Like Mike I prefer to see things the "right way round" although as a telescope user as well, it does not really matter in space!

I am a fan of parallelogram mounts and have 2. Yes, they are more expensive but are steady and comfortable sitting down or standing up. Great at star parties and also easy for my 9 year old to look through at his own height!

I find it easier to star hop my way around looking for objects if the map and the view are oriented the same way and its easier to remember next time I am in the vicinity.

Nonetheless, I have heard good reports from the mirror based alternative as one can sit in comfort, take notes on the table and not strain ones neck. (neck strain is not an issue with the paralleograms except when at the zenith)

malcolm :)
Malcolm Zack
Intes Micro MN66 on EQ6 Pro.
120mm Skywatcher Evostar DS Pro APO on Celestron CGT 5. WIlliam Optics 72 ED
ETX 90, Irving 76mm Refractor.
Bins: - 7*50 Fujinon, 9*63 Meades, 10 * 70 Fujinon and 20*80 Opticrons on parallelogram mounts. Fujinon 8*32s ( daytime use)
Gregger
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Post by Gregger »

This thread has lots of debate on these types of mirrors
http://www.popastro.com/phpBB2/viewtop ... highlight=

I made the one in the picture and have made a 50% bigger one to house my 20X80 Helios Binos.

If you go to

http://www.astro-engineering.com/

Scroll down the left hand menu to "Sky Mirror". I bought my dad one of these last year. This easliy takes binos upto 20x80 and is top kit.

I think we'd all agree binos are top pieces of kit for starters and seasoned veterans alike. Give great widefield views.

Personally, I dont know how the other cope with neck strain. I got rid of my 100mm bins as too painful to use. I love these refelcting mirrors. Make observing so much easier. The wrong way round image does make them more awkward I feel so I too use a laser pointer to reflect off the mirror. Condensation needs to be thought about and they need to be cooled down slowly before taking them out.

On Tuesday I had lovely views of Kembles Cascade. Located through normal 10x50's the but could only look for 10sec at a time. Used the mirror viewer and had rock steady views for as long as I wanted (except it was upside down!).

Great devices IMHO.
Paul Sutherland
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Post by Paul Sutherland »

mike a feist wrote:
Mike makes the common mistake of thinking that the field is laterally reversed in a "SkyMirror"; the image is, in fact, upside-down as in an astronomical telescope.
Just done an experiment with a mirror and binoculars. Yes the left and right are not reversed but the picture is upsidedown. The sign that I am looking at it upsidedown but even by rotating it in my head the words are back to front though.
I'm slightly puzzled by all this. A flat mirror in itself does not turn an image upside down, so it must be due to the angle of view of the reflection made with the binoculars. This is quite different to the inverted image that one gets from using a certain combination of lenses in a telescope. Similarly, if I stand in front of a mirror at home, I am not turned upside down either.

It reminds me of that old chestnut where it was asked why a mirror reversed you left to right but didn't reverse you top to bottom. Of course it is a misconception that you get reversed left to right. You don't. Your left hand is still opposite your left hand's reflection and your right hand is opposite your right's reflection, just as your head remains opposite its reflection and feet opposite theirs.

Paul
Last edited by Paul Sutherland on Sat Nov 01, 2008 10:20 am, edited 1 time in total.
brian livesey
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Post by brian livesey »

Every which way.. . :lol:
brian
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