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View Full Version : Looking to buy binoculars, anyone heard of these?



Johnno
2002-Sep-02, 11:28 AM
I found a pair on sale on a webshop for a company that imports binoculars and telescopes to norway.

Russer 16x50

I did a few quick websearches but couldnt find out anything about them. There is no avaliable information on the webshop, would need to email them and ask for details.

Any help would be appreciated

Johnno

PS. They're very cheap, cheaper than 10x50 binoculars. But I guess that's because they're on sale.

Surly Joe
2002-Sep-02, 11:29 AM
Yikes! 16x50, and you plan on stargazing? They'd be waaay too shaky unless you're using a tripod. Even then, your FOV is gonna be very small. I'd suggest going for some 7x50s. That's what I use, and they're awesome.

Johnno
2002-Sep-02, 11:41 AM
Yes I would be stargazing, mostly looking at the moon. And yes I have a tripod.

But you do have a point, perhaps I should go for 10x50 instead? Or do you think I should go all the way down to 7x50?

Surly Joe
2002-Sep-02, 11:47 AM
Well I've used 10x50 and 7x50 side-by-side and I personally prefer the 7s.. the objects seem brighter. The difference between 7s and 10s is really negligible, in my opinion. One gives you a slightly larger object, and a slightly smaller field of view. The other makes the object slightly brighter, with giving you slightly more field of view, and a sturdier image if you're hand-holding them. Actually the shakiness of 7s compared to 10s when holding is much better, in my experience.

For looking at the moon.. hmm. I'd say anything you can hold still will do, heh. The moon's pretty bright. Don't want anything with a FOV so small you can't fit the moon in it, though.

But I'm no expert, perhaps someone with a little more actual information can interject something?

_________________
Absence of evidence is not evidence of absence.

<font size=-1>[ This Message was edited by: Surly Joe on 2002-09-02 07:48 ]</font>

Johnno
2002-Sep-02, 11:53 AM
Well I think I will mostly be using my tripod, but not when travelling (if I bring the binoculars on a camping trip for example).

Just curious, what sort of experience can you expect with the 7x50? I mean what different objects will you be able to see?

How far do I have to go if I want to see planets for example...

<font size=-1>[ This Message was edited by: Johnno on 2002-09-02 07:53 ]</font>

Hale_Bopp
2002-Sep-02, 02:12 PM
Well, if you want to see planets, you can see five (six counting the Earth as the old trick question states) without any binoculars. 50mm binoculars also will easily catch Uranus. A few asteroids will also be within reach from time to time.

However, you are not going to see detail on any of the planets with 10x50 or 7x50 binoculars. You really need the higher magnification of a telescope to get details on a planet.

With that being said, however, some objects actually are better viewed through binoculars. Large open clusters such as the Pleaides and the Beehive are more impressive through binoculars due to the large field of view. Even the Andromeda Galaxy is very good through binoculars. Just look anywhere near Sagitarrius with binoculars and you can't help but stubling onto spectacular star fields and clusters.

And every now and then, comets are a treat in binoculars /phpBB/images/smiles/icon_smile.gif

Binoculars are very underrated for astronomy and every astronomer worth his salt should have a good pair! They are also the ideal first instrument.

I also agree that you want either 7x50 or 10x50. I have a pair of 20x80 and it is very difficult to hold them steady. I usually use a tripod, but what a view!

Rob

Johnno
2002-Sep-02, 02:29 PM
ok thanks for all the help guys, I'll see what I end up buying, but I'll keep in mind what you all said.

Johnno

Chuck
2002-Sep-02, 03:14 PM
Shakiness can be reduced by lying on your back with your elbows on the ground. Leaning against a wall or tree can also help.

Gramma loreto
2002-Sep-03, 07:32 PM
I've done a fair bit of stargazing with binoculars and IIRC, you want an "exit pupil" of 5mm or larger.

To determine the exit pupil, divide the objective diameter by the power factor. In the case of the Russer 16x50 binocs, the exit pupil would be 3.125mm...not so hot. 10x50s (which I've used) are 5mm while 7x50s are slightly better at about 7.14mm.

Squaring the exit pupil numbers gives a value of relative brightness, giving you a rough idea of how bright one pair of binocs are compared to another. So, in the examples above, the respective relative brightness values would be, ~9.77, 25, and ~51.

Hope this helps.

aurorae
2002-Sep-03, 08:05 PM
There are several good books on stargazing with binoculars. These give lots of advice on things to look for. I like Nightwatch by Dickson, Harrington's book Touring the Universe with Binoculars among others.

Personally, I tend to use my binos to help me find a troublesome object (scouting out a region for my telescope), as well as just scanning sections of the Milky Way (from a dark site, I can do that for hours).