Low light scope expectations. How much better are they than the Leica I might return?

[Tl15]

I never bought a Polar because I demand illuminated reticles for hunting black pigs in dark brush and the ridiculously stupid seperate illumination control that S&B uses confounds mounting the scope easily and looks incredibly impractical. When they fix that, I would consider buying one just to see what the fuss is about.

As to the Magnus, if you go by the product literature, the Fortis actually surpasses the Magnus line now in theoretical performance. That tracks considering how old the Magnus design is.

 

[KenLee]

A couple weeks ago europtic had some of the t96 marked way down. I’m not sure how the glass in the Leica er5 compares to the amplus but, I have a er5 4x20x50 & a leupold vx5hd 3x15x56. The vx5hd is the better low light & through the magnification range.

ER5 3-15x56 is just as good with light as the same VX5 HD, and more dependable. Amplus is a little better and has illumination.

 

[stevevan]

ER5 3-15x56 is just as good with light as the same VX5 HD, and more dependable. Amplus is a little better and has illumination.

Guess my experience is different. I have 3 of the 3.5-15x50 Leica Amplus6 scopes and they work real well past legal shooting light.

 

[KenLee]

Guess my experience is different. I have 3 of the 3.5-15x50 Leica Amplus6 scopes and they work real well past legal shooting light.

What did I say that was different than your experience?

 

[ChrisAU]

I used a 50mm Amplus 6 some last season and looked through a 56mm on a friends rifle. I can't fathom anything being noticeably better to the point that a no-shot scenario becomes a dead animal.

 

[Spoobs]

This thread might give you some ideas:

Low light comparison of 17 scopes

There are always constant threads of discussions about “glass”, low light use, etc of scopes here. The last couple of week I have gotten many more questions about it (due I believe to SWFA being back in stock), so while working with a couple of scopes on other things, I brought out 10 different...

rokslide.com

lol, I'm exactly his audience. The only model I see in here that's consistently highly recommended for low light from my research is the S&B 8x56. It's interesting to see this users report: "Conclusions at legal sunset: “glass” differences in the timber made no difference in ability to make a shot- none whatsoever with these scopes. Reticles however, made a very large difference."

If the 8x56 is a good as people say, it's likely the more premium optics are going to be similar.

If you don’t need to dial for range, the 8x56 Schmidt and Bender is as good as it gets.
The 2-10 Trijicon would be my best bang for buck pick. We can legally hunt one hour after legal sunset here in SC, and the Trijicon is a very popular scope for guys trying to stay in the stand till the very last minute.

Honestly I don't really care about BDC for my hunting rifle. I'd be lucky to get an opportunity to shoot pass 200 yards. The 8x fixed zoom is a problem for me tho, I suspect I'll mostly be around the 2-6x zoom range as I want large FOV.

Can you still get the magnus in the US?

Not from a retail distributor. I've seen one on gunjoker with the zeiss rail mount option, and there was a user here who had one for sale in the classifieds about 6 months ago. Pretty rare I see these on second hand sites.

 

[Spoobs]

Can’t buy your way around physics. Exit pupil is everything. All the bigger objective is buying you is the ability to run higher magnification at the same apparent brightness.

That said, coatings and light transmission DO make an objective difference in the last few minutes, but that’s really what we are talking about here, minutes.

Interesting, I was under the impression objective size collects more light and thus results in a brighter image. The Amplus 6 2.5-15x56 has the same exit pupil as the 2.5-15x50 at the lowest magnification (11.6mm) and at max magnification the exit pupil is 3.7mm and 3.4mm respectively. The difference doesn't seem that huge and I honestly only seeing myself using magnification above 10x at the range in daylight. If this is true I may have been better off getting the x50 so I can get lower rings.

54 or 56mm Polar at 2-3x the price is your choice if you need better low light performance than a 56mm Amplus.

I got the Amplus 6 for $1179+tax, with the T96 on sale their price difference has never been so close. If they are getting discontinued it's possible they may go on clearance, but not before my return window on the Amplus runs out.

if you go by the product literature, the Fortis actually surpasses the Magnus line now in theoretical performance. That tracks considering how old the Magnus design is.

The magnus was on my radar first. I had an unjustifiable bias to try a Leica, one of the reasons I got the Amplus to begin with. It really is the best scope I've ever looked through, but I guess my expectation for low light was really high. The fortis has the same availability situation in the states as the magnus unfortunately. No US distributor offers them, I heard it was because of patent infringement but I never looked deeper to confirm this story so take that with a heavy grain of salt.

I used a 50mm Amplus 6 some last season and looked through a 56mm on a friends rifle. I can't fathom anything being noticeably better to the point that a no-shot scenario becomes a dead animal.

Your friend had the 56 version of your scope? Was there any brightness differences at low magnification?

 

[Southern Lights]

Square area of a circle shows potential here as a rough guide:

50 mm Objective Area: Approximately 1963.5 mm^2
56 mm Objective Area: Approximately 2463.0 mm^2
Increase in Light Gathering (56 mm vs. 50 mm): About 25% more.

If you want best low light, ignoring other factors, look at larger objective first. It's always possible the rest of the scope design compromises the objective size light gathering, but all else equal: Aperture wins.

Second factor is going to be using low magnification. With telescopes, higher magnification results in a dimmer view even on large aperture scopes.

 

[Mtank79]

If you can, tell me the secret

I second that, I was trying to find out his secret.

 

[Mtank79]

Can’t buy your way around physics. Exit pupil is everything. All the bigger objective is buying you is the ability to run higher magnification at the same apparent brightness. It’s all equal once the exit pupil size exceeds your dilated pupil.

That said, coatings and light transmission DO make an objective difference in the last few minutes, but that’s really what we are talking about here, minutes. An extra $2k might buy you 5-6 minutes, but you’d be better off spending that money on a second hand set of Swarovski EL’s or Zeiss SF’s and have some left over for a tank of gas and a good steak. That was ultimately what I did. Bought a pair of SF’s and capped scope purchases at $1,200. That’ll get you good quality European glass with illumination. I live in my binos, the scope is just to park the dim red dot on the vitals of the predesignated animal. It has completely changed the game in how nice my hunts are now, and eased pressure on my bank account.

I’ve got an Amplus, it just bumps past the V4’s to my eye, but it’s not a profound jump. Both beat out the VX5-HD series and Trijicon Credos. Both fall under the V6, but that’s to be expected. I’ve got a Steiner H6Xi that is going on a whitetail hunt with me this weekend. I’ll have a good eval of it versus the V6 when I’m back.

I’m looking forward to hearing your thoughts on the h6xi. It’s on my list for a possibility. My top 3 options swaro x5i 3.5x18x50, zeiss v6 3x18x50, Steiner h6xi 3x18x50.

 

[Tl15]

Square area of a circle shows potential here as a rough guide:

50 mm Objective Area: Approximately 1963.5 mm^2
56 mm Objective Area: Approximately 2463.0 mm^2
Increase in Light Gathering (56 mm vs. 50 mm): About 25% more.

If you want best low light, ignoring other factors, look at larger objective first. It's always possible the rest of the scope design compromises the objective size light gathering, but all else equal: Aperture wins.

Second factor is going to be using low magnification. With telescopes, higher magnification results in a dimmer view even on large aperture scopes.

That’s not how that works optically however. The area of the objective is only relevant in calculating the exit pupil and matching it to the pupil size of the dilated eye. The average guy’s pupil will dilate to 7-8mm in very low light. As long as the exit pupil of the scope matches that size, there is nothing more to be gained from a larger objective. Exit pupil is simply objective diameter divided by magnification power. Therefore, a 56mm scope will give you a 7mm exit pupil at 8x magnification. A 50 will give you the same apparent brightness at ~7x, and a 42mm will give you the same apparent brightness at 6x magnification. All the images will look equally bright because the cone of light entering the eye covers the entire pupillary opening. At any mag lower than 6x, all of these will look the same despite the differing objective sizes. A 56mm comes into its own when you need 8x magnification, like hunting over ag fields or long timber/brush cuts. If you’re hunting at 100yd and in, you really don’t need that much zoom and can get away with a smaller objective and lighter scope.

If you are implying that total light entering the optic directly equals apparent brightness, I would really hate looking through a big spotter during midday sun, and I’d start a scope company, slap a 100mm bell on the end of a tube and crown myself low light king.

 

[Southern Lights]

That’s not how that works optically however. The area of the objective is only relevant in calculating the exit pupil and matching it to the pupil size of the dilated eye. The average guy’s pupil will dilate to 7-8mm in very low light. As long as the exit pupil of the scope matches that size, there is nothing more to be gained from a larger objective. Exit pupil is simply objective diameter divided by magnification power. Therefore, a 56mm scope will give you a 7mm exit pupil at 8x magnification. A 50 will give you the same apparent brightness at ~7x, and a 42mm will give you the same apparent brightness at 6x magnification. All the images will look equally bright because the cone of light entering the eye covers the entire pupillary opening. At any mag lower than 6x, all of these will look the same despite the differing objective sizes. A 56mm comes into its own when you need 8x magnification, like hunting over ag fields or long timber/brush cuts. If you’re hunting at 100yd and in, you really don’t need that much zoom and can get away with a smaller objective and lighter scope.

Yes and as we age ability for the pupil to dilate goes down also. The objective and magnification are both in play and I wasn't clear. The larger objective though is able to collect more photons and also produce more contrast which is something the human eye also perceives as a better/brighter image.

ClarkVision: Visual Astronomy: M51 and Telescope Aperture

If it's so dark that I think a larger objective is going to fix things, I'm going to thermal/IR dual mode which is safer as I can positively identify what I'm shooting at without any guess work. Again though I understand if this is not legal for some people. But if it is, I would just go that route.