Scopes at dusk

[Rich]

Scopes at dusk

March 15, 2010

This evening I compared the 13X56 Minox, Bushnell 6500 4 ½-30X50, and the 12-42X56 NightForce. The Minox was on a tri-pod. The two scopes were on the edge of the porch. I didn't touch them while looking through them. I tried to get the magnification the same on the rifle scopes to match the binoculars. I pick the words “THIS SIDE DOWN” on the pump house siding about 115 yards from the porch. The following gives the times when I could no longer read the words without resorting to trying to make out individual letters.

Minox 13X56
6:42 PM
Bushnell 6500 4 ½-30X50 ~ 13X
6:44 PM
NightForce 12-42X56 ~ 13X
7:00 PM

After the Minox could no longer read the words I turned the Bushnell 6500 up so I could read the words again. This required 18X. Each time I turned the power ring up to what was required to read the words again. The following are the minutes I could no longer read the words with the Bushnell 6500.
18X – 7:03 PM
20X – 7:10 PM
26X – 7:16 PM
30X – 7:24 PM

While I was turning up the Bushnell, I did not have to turn the NightForce up until 7:00 PM. I then turned it up till I could read the words again. This required 16X. The following are the minutes when I could no longer read the words with the NightForce.
16X – 7:11 PM
20X – 7:16 PM
22X – 7:25 PM
24X – 7:27 PM
26X – 7:28 PM

[LeeInSC]

The higher you dial the power, the less light transmitted. So your ability to read the print at higher power is due to the power to make the letters look large enough to offset the loss of contrast with the paper.

I might shoot early in the morning, but not at dusk. I want to be able to track the game if necessary, which requires daylight.
I also want to be safe by seeing the backstop beyond my target. Bright, clear binoculars and rifle scopes benefit my hunting style by letting me look into the shadows and pick out game in the big woods. The clarity means I don't need as much power to place the shot precisely. If you want to see the ultimate, look through some quality 7x50mm binoculars or 6x42mm scope at night, with just starlight and maybe a little moon.

[Bushman]

Rich, you have way more x's in your scopes than most guys hunting in low light. The largest scope front objective lens diameter that I have is 42 mm aside from my spotting scope. When you divide the front objective diameter by the power that you are using, you are coming up with some very small exit pupil sizes that are much smaller than what your eye could actually use in very low light. What was the second plane cross hair image doing when you increased the power on your scopes. That was my problem when I was shooting deer at first available light. I couldn't see the cross hair with my Leupold. First plane reticles in my Zeiss and Swarovski variable scopes solved that problem and the heavy duplex cross hair in a newer Leupold helped a bunch too.

[Rich]

Bushman,

Someone suggested I turn the power ring down and I will be able to see better as it gets darker. Last night I put that to the test. My son-in-law was invited to partisipate just for another opinion.

This time I used only the 4 1/2-30X50 Bushnell. I started with it on 20X. Both of us agreed that we could not read the "THSI SIDE DOWN" any longer. I turned the magnification down to 16X. John said it was a lot brigher but sitll could not read the words. I didn't noticed the brighter and also could not read the words. Therefore I conclude more magnification is benificial for low light identification of horns; if they have the words "THIS SIDE DOWN" on them.

[pepaw]

Thanks for your test results. I don't have any scopes over 9x, but still interested in low light tests. We hunt hogs 24/7 here in TX.
I will be searching for a new scope soon, but have to thin the current inventory first.

pepaw

[LeeInSC]

If you are hunting at night, by moonlight or maybe a flashlight shining out there at a not-so-close target, the place to start looking would be with what the Germans use for night hunting big boars, an 8x56mm scope, which has a 7mm exit diameter, the most usable by even a young human eye. The 6x42mm also has 7mm on the ocular end. I have used my Zeiss 6x42 and a Kahles ZF 6x42mm at night, and you can see hair, eyes, and all sorts of details just by a little bit of moon light.

[Rich]

LeeinSC,

Based on my two test, I would definately take a variable 56X over a fixed 8X56. When you can't quite make out if it has the horns you want, you can turn up the magnification and imporve your vision.