Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_lunar_landings.thumb.jpg.b50378d0845690d8a03305a49923eb40.jpg

Scooot

Moving from 10x50’s to 8x42’s

Recommended Posts

I’ve often read 10x50’s are the ideal binocular size providing a good balance of weight, aperture & magnification. I’ve had my 10x50’s for a long time now and they’ve given me some great views. However I’d often craved for a wider fov whilst scanning constellations, just a little bit extra to put the view into more context, so I recently bought some Victory 8x42’s with a 7.8° Fov.

I’ve now used them a handful of times & I’m really enjoying them. For such a relatively small difference in fov they provide a surprisingly different experience. I can’t quite see as many DSO’s, but I can still see the likes of M13, M15 & M38 (but not M36, so far anyway), or maybe the other way around. My light pollution made DSO’s quite difficult to see in my 10x50’s anyway, so I’ve come to enjoy the star clusters and patterns across the sky with binoculars. With this in mind  I can now see nearly all of Lyra, and more of some of the fainter constellations that are not visible to me naked eye, but with a good magnification and optical quality. It is much easier for example to pick out Delphinus and Equuleus and to hop between star groups whilst maintaining my bearings. M15 is easy to pinpoint as I can just triangulate from Enif & Delta Equ. Something new the other evening was the Circlet just South of Pegasus and whole head of Draco. I also had some stars visible in the same field as the full moon, I don’t remember this with the 10x50’s.

Although I haven’t had them long, I think 8x42’s are going to be much better for me than 10x50’s. :)

E7FDD309-402E-4A22-B8FB-FADB47557AF5.thumb.png.8d2d357e10ca2fc8d55b54c8d2b699ef.png

669B7803-46AA-41D8-A418-5A0E130F83AE.thumb.png.9350078e186463eb7545c869184e7dc1.png

 

  • Like 5

Share this post


Link to post
Share on other sites

Strange but technically the 8x42's should be marginally brighter then the 10x50's. They are smaller aperture but the magnification is just such that the resultant image should be just a little brighter. Although a bit smaller in image size.

The rule was divide the aperture by the magnification and the bigger result is the brighter. 8x42's just win out. But there is the question of what is going on inside, however I would have expected that the 10x50's were if any the most likely to be reduced in aperture internally - a suitably placed internal baffle to reduce CA, stray light etc. Also the quality of the binoculars are a big factor.

 

Share this post


Link to post
Share on other sites
4 minutes ago, ronin said:

The rule was divide the aperture by the magnification and the bigger result is the brighter.

This is the calculation for exit pupil so yes, it will give an indication of image brightness.

The 8x42s have a 5.25mm exit pupil vs 5mm for the 10x50s so will have a slightly brighter image, not much though.

I have some Barr & Stroud 8x42s and find them very nice. 8.2 degree fov and a nice compact unit to hand hold. They are both ED glass so do show some CA but at the lower power this is not so much of a problem.

Share this post


Link to post
Share on other sites

I haven’t had very dark skies yet so maybe that’s the difference, & Auriga is still not that high in the evening. Andromeda is certainly very nice :) 

The 10x50’s are the William Optics ED so very good optically as well but I didn’t compare them side by side on the same nights.

Edited by Scooot

Share this post


Link to post
Share on other sites

Just had a bit more fun with the 8x42s. Conditions are very poor, the Sky is clear but very milky, can’t make out much with the naked eye so I’ve been lying back in a garden chair concentrating on cassiopeia. Using the square in the asterism “Cassiopeia’s Chair”, I could easily quickly get my bearings. I love the owl cluster in a scope so first looked for that. By placing Ruchbah, Navi & Shedar in left field it was easy to confirm the sighting. I could only see the two bright eyes of the owl, which looked like one star, but because of the overall view there was no mistaking it.

After this success I decided to try M103, so moving slightly down, and using similar tactics I placed Ruchbah and Segin in the same fov & low and behold there it was, exactly where it should be. A quite large faint dusty patch. What was even more surprising was I could also see Ngc 663, which was a larger dusty patch. I eventually confirmed this to myself by reference to the trail of 4 stars just above it. I really like these bins! :) 

80FF2E96-BCF9-4BE8-B187-8867B3CC693D.thumb.png.53405fe25c15edc98c13699c14764e26.png

99952BB2-CA75-4284-82E0-2E92449EF468.thumb.png.c0b004f423dc9afaff1f89c56262e505.png

 

Share this post


Link to post
Share on other sites
On 15/10/2017 at 16:12, Scooot said:

I haven’t had very dark skies yet so maybe that’s the difference, & Auriga is still not that high in the evening. Andromeda is certainly very nice :) 

The 10x50’s are the William Optics ED so very good optically as well but I didn’t compare them side by side on the same nights.

Great topic/post, thanks!

Don't worry about Auriga, last summer I was round a friends house and she had a very old pair of 8 (or maybe 7) x 30's and we were easily able to make out the lovely Auriga run of Massiers 36, 37 & 38 along with a hint of IC405. I love this run of M's.

Also I recently bought a pair of 8x42 Celestron trailseeker bins and they're a joy to use on a clear night!

  • Like 1

Share this post


Link to post
Share on other sites

Slightly off topic, sorry, but can I ask what program or app you used for the screen grabs, this looks really interesting.

Thanks

Jeremy

  • Like 1

Share this post


Link to post
Share on other sites
36 minutes ago, Sky-J said:

Slightly off topic, sorry, but can I ask what program or app you used for the screen grabs, this looks really interesting.

Thanks

Jeremy

Thanks for your comments :)

Its Sky Safari. A superb app. I'm using Sky Safari 5 Pro but all the versions are excellent.

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By astronomer2002
      I thought my eyepiece collection was complete until I bought my "last ever" telescope. This operates at a native F8 and is just over 3250mm fl.
      I have the longer Naglers, 31, 26, 22, 17 etc and  35mm, 27mm Panoptics.  I was always a little disappointed with the kidney-beaning in the Naglers in other telescopes, though they were overall better than any other eyepiece I have used, but in this one they seem to be affected less and even the 26mm  is now a keeper. Before I got the Naglers (over many years all s/h) I had 35, 27 and 19 Panoptics. These were my favorite eyepieces until the Naglers came along. I kept the 35mm as stars seemed a little sharper in the inner 50 degrees than the Naglers, but trailed off in the outer regions and the 27mm as it really is an exceptional eyepiece.  In any case I often wanted to darken the sky with higher magnification so the longest ones were primarily used for sweeping and finding. Given sky brightness is becoming more of an issue I thought I would never need a longer focal length. Now the Naglers seem sharper over the entire view and with the higher magnification of a longer scope the sky is darker and I hanker after the widest possible field.
      The issue is that the 82 degree 31mm Nagler gives me a true fov of 0.78 degrees and the 35 mm Panoptic 0.73 degrees. There is noticeably more sky in the 31mm Nagler. A 41mm Panoptic will yield 0.85 degrees, an improvement of nearly 10% over the Nagler 31. As I can readily see the difference in the amount of sky covered by the 31mm Nagler and the 35mm Panoptic I believe the time to look at a 41mm Panoptic is here.
      Before going into a debate on whether ES eyepieces could fill the slot all I can say is that having been able to compare my old Naglers with new 82 degree ES ones in my scopes I and convinced that, for me, there is a small improvement with the Naglers at the outer regions of the field and so I am minded to discount them. They are fantastic value and I won't deny they are very good eyepieces.
      The 41mm Panoptic would seem fit the bill for this long fl scope though I suspect it would be a disaster in a fast Newtonian, which I also have.
      My quest is to find someone willing to part with theirs and/or suggestions of an alternative that someone has used in practice.
      Thankyou for reading
       
      Ian B
       
       
       
       
       
    • By pixelsaurus
      Predawn sky December 25 2011. 30 sec, Tokina 28-80mm @ 28mm, f/3.5,Pentax *ist DS, ISO 3200. Otaki Beach,NZ.
    • By steppenwolf
      Before I start running my fully automated observatory from a remote location, it is useful to know what the weather conditions are like at the observatory site and an all sky camera is a great way of seeing what is going on in conjunction with my AAG CloudWatcher that 'measures' the weather conditions.
      Unfortunately, commercial all sky cameras have a pretty hefty price tag and I had a very limited budget for this project so I decided to make my own. The camera is the easy part and the excellent ZWO ASI 120mm was an obvious choice - it even comes with a 150° wide angle lens. However, the key to a reliable all sky camera is the enclosure it operates in. A camera and lens combination like the ZWO will work very well on its own for this purpose right up until the dew forms on the lens or even worse, it starts to rain so a waterproof enclosure with its own heating system is a prerequisite.
      Before I even started to think about the enclosure itself, I gave a lot of consideration to the heating aspect. The solution was sitting in my bits and pieces drawer - the components that I'd bought in a couple of years ago to make a dew-band for my 28mm camera lens when I wanted to capture a meteor shower! I never did make the dew-band but the Nichrome wire and pulse width modulation (PWM) power supply were perfect for this project. I calculated that I would need up 8 watts of heat for a 'de-frost' but a lower output for general use.
      With the heater resolved, I looked around for a suitable transparent dome for the enclosure and found a 100mm diameter dome for under £10.00 on Ebay. All I needed then was a suitable box to match the total width of the dome and again, Ebay came to the rescue.
      Awful skies mean that I have used it very little but I have enjoyed making time lapse videos of the night sky and I ended up buying a fisheye lens for the camera to give me a full 180° view.
      So here's the camera enclosure in all its glory

      Click here to view my first light timelapse video
    • By wimvb
      NGC1499
      17 * 3 and 4 mins frames
    • By wimvb
      Wide field around Mirach
      Shows the relative position and size of M31 and M33. To the far left is Schedar (a-Cass). Just below it is a tiny nebula (NGC 281).
      22 2 min subs, flats, darks and bias
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.