New Posts New Posts RSS Feed - Exit pupil & low light performance
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Check GunBroker.com for SWFA's No Reserve and No Minimum bid firearm auctions.

Exit pupil & low light performance

 Post Reply Post Reply   Topic Search Topic Search  Topic Options Topic Options
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/10/2005 at 09:28
Stud Duck View Drop Down
Optics Journeyman
Optics Journeyman
Avatar

Joined: May/20/2005
Location: WV
Status: Offline
Points: 506

I've decided to take the plunge and purchase a set of premium binoculars, but I'm still in "Analysis paralysis."

I'm a medium & big game hunter who will be depending upon my binoculars for low-light performance.

 

When you step into the world of premium binoculars, how much of a factor is the exit pupil on low-light performance?

Will a set of Leica 8x50mm Trinovids out perform a set of 8x42mm Trinovids; will a set of 8x Leicas out perform a set of 10x's, just based on the exit pupil? Is the difference going to be significant enough to matter? (i.e. 3-4 minutes of viewing time at twilight) Would like some recommendations for low-light binoculars based on in the field, real world experience, not glassing the mounts at a Cabelas store.

 

Would like to see someone put together an optical rating system for binoculars based on low-light performance & resolution like T-bone & Chris did for rifle scopes. This would really be beneficial for prospective buyers.

 

Thanks again.

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/10/2005 at 12:02
tbone1 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: May/31/2004
Status: Offline
Points: 195

This is a question that has concerned me for quite a while as well.  The only way to be sure is to do side by side comparisons with the exactly models.  I own a pair of Leica 10x42 and 8x32 and my best friend has a pair of Swarovski 10x50.  I have compared them all side by side and used them all in the field but I don't have a Leica 8x42 or Swarovski 10x42 to compare.

 

In my opinion exit pupil is only part of the equation.  Another calculation often overlooked is twightlight factor, which generally increases with magnification.  Now I am not one who believes in relying on mathmatical equations to pick binos, I prefer real world side by side tests.

 

Comparing 8x vs. 10x of the same objective.  In my experience the 8x may technically be brighter but it won't necessarily allow you to see any better.  The difference in brightness is very minimal but the higher magnification will allow you to see more details (pending that you can hold a 10x steady).  If you place a resolution chart at a given distance and compare 8x vs. 10x until dark.  The 10x are going to outperform the 8x regardless of the brightness.  You will be able to see slightly better with the 10x.  That doesn't mean that I prefer 10x, but I can see slightly more details with them.

 

Comparing binos of equal magnification but increasing objective size.  My friend and I  compared my Trinovid 10x42 against his Swaro 10x50s until dark and could not detect any difference in brightness at all.  Now I am not sure why but I personally believe that increasing objective size to gain a higher exit pupil often offers very minimal increase in brightness.  However I am still considering a pair of 10x50 Ultravids.

 

Honestly, it is a very difficult choice.  One that I am struggling with as well, since I am considering another pair of binos.  I would not let exit pupil be the predominating factor. I would choose based on the terrain that you hunt, the bulk and weight that you want, and which feels more comfortable to you.  I would prefer an 8x for woods and 10x for hunting mostly wide open terrain.  To me a 4mm exit pupil is perfectly sufficient and a 5mm is as good or better.  I personally think anything over a 5mm is unnecessary.  If you choose an 8x then you really don't need a 50mm objective.  If you choose a 10x then 42mm or 50mm would be fine.  The 50mm could possibly be a little brighter but also much more bulk and weight.  If you do take the plunge on a top quality set, you will not regret it.  To me top quality binos are worlds better that mid-quality and there are only minimal differences between 8x vs. 10x and 42mm vs. 50mm.  I hope this helps you.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/10/2005 at 14:25
Stud Duck View Drop Down
Optics Journeyman
Optics Journeyman
Avatar

Joined: May/20/2005
Location: WV
Status: Offline
Points: 506

tbone1

 

Your answer really helped, I appreciate the in-depth response. I think you've gotten me through the "Analysis Paralysis."

 

Now you & Chris need to get to work on that rating system for binos.

 

Thanks.

 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Similar Threads: "Exit pupil & low light performance"
Subject Author Forum Replies Last Post
Low Light Performance Rusty Binoculars 7 8/2/2005 9:45:36 AM
Best low light performance w/o glare CWPINST Rifle Scopes 5 8/9/2004 2:30:12 PM
Best low light performance under $700 CWPINST Rifle Scopes 14 10/25/2004 3:29:15 PM
Super Sniper low light performance Red_SC Tactical Scopes 8 12/10/2004 11:56:40 AM
Optical performance & durability Stud Duck Binoculars 6 8/1/2005 2:51:47 PM
range performance tree vs. deer bigo_m Laser Rangefinders 2 2/18/2007 8:13:58 PM
Bino performance factors jeffbird Binoculars 1 9/22/2006 10:00:59 AM
Scope performance evaluation question SingingRiver Rifle Scopes 20 5/12/2007 7:24:08 PM
Low Light Scopes & Magnifications Qs cats9 Rifle Scopes 34
1.5-6x42 exit pupil questions dw0229 Rifle Scopes 2


This page was generated in 0.359 seconds.