Need help getting a pair of binoculars

[rlow]

would a 50mm show significant difference over a 40mm?

I have compared side by side 10x42mm vs 10x50mm binos and, all other things being equal, there seem to be no significant difference, just very minor differences, in my opinion. But there is quite a bit of difference in weight & size, ie the 42mm bino is slightly lighter and smaller, which is important if you have to carry and use the bino for a few hours of birding or astronomy.

There are more differences when comparing magnification. All other things being equal, higher magnification allows object to be more visible because image scale is bigger and the background sky is darker (higher contrast due to smaller exit pupil). However there is a tradeoff for binos as higher magnification means smaller true field of view (TFOV) and less steady image if handhold (and with a unsteady image, you see less detail). So if you are getting your 1st bino to star-hop and learn the constellation, I believe the 8x40 would be better. If you have steady hands and want a bino to observe binocular deep sky objects, the 10x50 would be more suitable. But you won't go wrong with either choice.

The Nikon Action EX series seems to be good value for its price range, and it has good reviews. I have checked out the Nikon Acton EX 8x40 which is waterproofed, wide field and with good eye-relief for those with glasses. However it is not sharp-to-the edge (which is expected if you are paying just $200) and the lens coatings are not the best (it is also not fully multicoated). But it should be good value for beginners. Do note that the Nikon Action series are cheaper, not waterproofed and not the same quality as the Nikon Action EX (ex for extreme).

[stargazer.23]

Thanks, Zane and Richard.

Just wondering, would a 8x40 be good enough to observe brighter deep sky objects like the orion nebula, pleaides, and maybe some open clusters?

My main reason for wanting a bino is really to see some of the brighter DSOs. So, does this mean that i should be getting a 10x50 instead? Or would a 8x40 function just as well?

Thanks all, for being so patient with my relentless questions.

[guangwei]

10x50 would be good enough, not so heavy. I own a 10x60 and i find it quite heavy as i don't have strong hands.

[rlow]

Just wondering, would a 8x40 be good enough to observe brighter deep sky objects like the orion nebula, pleaides, and maybe some open clusters?

My main reason for wanting a bino is really to see some of the brighter DSOs. So, does this mean that i should be getting a 10x50 instead? Or would a 8x40 function just as well?

I believe the 8x40 would serve well for the purpose as you described, and it being lighter, wider field-of-view and easier to hold steady will make it more useful for stargazing beginners, as compared to 10x50. Some people I know will not buy a 10x bino and rather go for a 8x bino as a shaky 10x view will result in reduced resolution, ie, you observe less details. If you have keen eyesight and use a 8x bino with high resolution, like my 8x40 Pentax, you will not lose out much compared to my 10x42 bino.

Just my opinion, as your milage may vary, so if you can, try to borrow and test out both types of bino first under the night sky before you decide which one to buy.

[VinSnr]

Thanks, Zane and Richard.

Just wondering, would a 8x40 be good enough to observe brighter deep sky objects like the orion nebula, pleaides, and maybe some open clusters?

My main reason for wanting a bino is really to see some of the brighter DSOs. So, does this mean that i should be getting a 10x50 instead? Or would a 8x40 function just as well?

Thanks all, for being so patient with my relentless questions.

Bro..I started astronomy with a 8x30 binos and that's 23 years ago.

Today, I am stilll loving it

I am sure the 8x40s will show you more than mine and hopefully, bring you more astro years too.

[rlow]

I f you want to test out the 8x40 Pentax and a 10X42 Nikon, I can bring them on the 29 May 09 at Tiong Bahru Park.

[stargazer.23]

Thanks Richard. I'll definitely come to the event if I can. Would be a great opportunity to meet fellow astro enthusiasts and learn from you guys! =)

[rlow]

OK, we will bring our binos for you to test this friday.

[stargazer.23]

Hi all,

I came across this pair of bino (Olympus 10x40 EXPS I) at Mustafa today.
http://www.olympus.co.uk/consumer/1942_10x42_EXPS_I.htm

Which would be a better pair for astronomy use in Singapore? This, or the Nikon Action EX 8x40 CF?
http://www.nikon.com.sg/pagearticle.php ... =79#Action EX Series

Can anyone advise please?

[Bergkamp_]

Best binoculars for stargazing
• Choose binoculars that have an objective lens with a large effective diameter or a large pupil diameter.
An aperture of 40 to 50 mm is suitable. When using an objective lens with an aperture over 50mm, use a tripod to avoid image vibration caused by binocular shake.
A pupil diameter of 5mm or larger is ideal. A diameter of less than 3mm is not recommended for stargazing.

Binocular aperture of up to 40mm is a great mid-range size that can be used by almost everyone for multiple applications. In this range, higher magnification becomes a little more practical. For those who enjoy stargazing, this is an entry level aperture that is very acceptable to study the Moon and brighter deep sky objects and they make wonderful binoculars for older children.
• Binoculars with a high magnification tend to amplify the shakiness of your hands.
Observe stars using a posture that allows you to firmly grip the binoculars. A magnification of 7x to 10x is suitable. It's a good idea to mount the binoculars on a tripod to stabilize the field of view and for safer observation over long hours.

What are binoculars and how do they work?
Binoculars are both technical and simple at the same time. They consist of an objective lens (the large lens at the far end of the binocular), the ocular lens (the eyepiece) and a prism (a light reflecting, triangular sectioned block of glass with polished edges).

The prism folds the light path and allows the body to be far shorter than a telescope. It also flips the image around so it doesn't look upside-down. The traditional Z-shaped porro prism design is well suited to astronomy and consists of two joined right-angled prisms which reflects the light path 3 times. The sleeker, straight barrelled roof prism models are more compact and far more technical. The light path is longer, folding 4 times and requires stringent manufacturing quality to equal the performance. These models are better suited to terrestrial subjects, and are strongly not recommended for astronomy use.

If you're using binoculars for astronomy, go with a porro prism design.



• Binoculars with high optical performance
High resolving power is necessary because you are going to observe stars, which are a point light source. Choose binoculars with high lens quality and performance that provide a sharp image to the periphery of the field of view.

• Waterproof or water-resistant binoculars
Choose waterproof or water-resistant binoculars so you don't need to worry about using them in night dew or when there is sudden rainfall.

• Choose binoculars that suit your observation style
Pick up the binoculars and look through them. Find the model best suited to your needs.