I get confused sometimes reading that 30 mm scopes can't be any brighter than 1" scopes, and the same with 42mm vs 50 mm?

So, if scope specifications lists a 3-9x50 30mm scope having an exit pupil of 5.7, and a 3-9x42 1" scope having an exit pupil of 4.4, then the larger scope lets in more light, right?
Thanks,

It doesn't have anything to do with the tube.

Difference between 1" and 30mm has to do with adjustment travel.

And, it has been debated on here since the beginning of the internet, but I personally think a larger objective is indeed brighter when comparing similar optics.

The reason that the first scope you mention will be brighter is because it sports a 50mm objective lens and the other a 42mm. If all else is equal when comparing two scopes (glass quality, lense coatings, internal design, flare control etc.) then the tube size is irrelevant.

OK, so it is only the objective lens size contributing to a larger exit pupil number?

Divide lens diameter by magnification and that's exit pupil.

Thanks guys, I finally get it.

Yes. Take a 6x42 Leupold scope for example and do as mathman suggested and you come up with a 7mm exit pupil. If Leupold built that scope on a 30mm tube or the offered 1" tube, it would make no difference with regards to brightness.

In modern optics you will discover with side by side comparisons exit pupil is irrelevant. If you want examples I will post them.

I can understand it being irrelevant comparing different qualities across different brands. But, are you saying of the same or similiar models?

Please don't encourage him.

Is it possible to put an entire thread on ignore?

I don't think so but I have a feeling this one's going no where.

Well my question is answered so I'm done. Bye.

I didn't think anybody could be this "short"

Pretty much, yes. You will see folks who have not done the side by side use ignorant prejudice to argue against facts, but fact are facts.

Objective comparisons are not facts...

despite Ringies 'comparisons', exit pupils do rate a thought. one of the downsides of too much magnification is tiny exit pupils.

Can Windex gather more light if used on the lens?

Only diamond-coated Windex can.

Machines are objective, but don't always tell us what will happen in the real world. Exit pupil is a mathematical number which truly is worthless. Like one of our .com friends posted, and I paraphrase:

"A brightly lit blob is still a brightly lit blob."

Yes they do. When folks I've spoken with lack the knowledge of what exit pupil means, I simply tell them, think of a fireman putting out a fire. Would he be better off with a 2 1/2" line or a garden hose.

How dare you insert logic into this conversation.

Ringman,

The exit pupil is not a worthless arbitrary mathematical ratio/number but in some sense a number that describes the aperture of the human eye as an optical system. Matching the scope's exit pupil to your eyes pupil maximizes the total light received by your eye and this assumes your eye is a typical eye and your retina's rods/cones can utilize the available light delivered from an increased exit/entrance pupil. Our eyes are atypical but this fact does not invalidate the physics behind the entrance pupil of the average human eye.

To your point, an increased pupil might make things brighter but for sure will make things smaller and I will not be the guy that argues against the resolution vs brightness trade, aka "a brightly lit blob is still a brightly lit blob."

After all, "a brightly lit blob is still a brightly lit blob..." but also "a high resolution picture is useless when the lights are off..."

Aic

Well I appreciate your kind words, however, if I may, just state that I wasn't really trying to use logic. I was stating a fact, like the sun is hot, water is wet, fat chicks can be fun...........

So true.

That is a fun argument. My experience and that of my son-in-law shows my Bushnell 4200 with a 40MM objective to last as long as my Swarovski z5 when both are on the same magnification setting. I tested them on the eye charts at 127 yards and the deer antlers at 131 yards.

The exit pupil of the z5 on any comparable setting is larger than the 4200 and yet is no better for either of us.

How bad is your eyesight and I don't mean that in a nasty way? Do you have vision problems?

In a nasty way or a nice way my glasses corrected vision is 20/15 during the day.



1. I am near sighted. 2. The doctor told me on a night vision scale most folks are at fourteen. If a person sees the same in the night as the day he would be a one. If you are at thirty-six you are totally blind in darkness. He told me,
"Don't be caught out after dark without a flashlight. You are thirty-two on the scale."

The reason I include my son-in-law is because there are some here who try to disparage my comparisons of optics because of the night blindness. I wonder how they think that influences comparisons done during normal day, but they think it because they post it. My son-in-law can see in the night without a flashlight. He is approaching fifty years of age and told me the other day he noticed he can't see quite as well as he used to. I tested him by checking something with a flashlight and then going into the house and requesting him come out and tell me what is over by the big tree about fifty yards out. He got it right. So I guess he can still see O.K.

I hope this answers your question without being argumentative.

I guess the question arises since if your pupils never get larger than 2mm then why should the exit pupil?

IMO, an exit pupil larger than my eye pupil is much quicker and user friendly. your eye does not have to be PERFECTLY aligned with the axis of the scope. downside is some parallax, which of course can often be ignored unless working on tiny, distant targets.

I guess for someone whose pupil never exceeds 2mm then a 2mm exit pupil would be good enough. Mine opens to 5mm in low light. I have no idea what my son-in-law's opens to.

Do you know the details of your night blindness? Is it a lack of appropriate working receptors in your retina?

No. My guess is there are more cones than I need and not enough rods. I find a lot of game by a slight difference in color, but sometimes I see an ear or a tail or part of an antler. Once I found a deer because I noticed the lower portion of the deer's back leg.

If your pupils dilate to 5mm at almost age 69, that's pretty good Rich. If it were me, I'd want to know if there was a cure or something to at least slow the process for your vision issue.

How can you evaluate the effectiveness of certain optics in the dark.? Would not your experiences differ from someone that did not have your condition?

There are very few who can evaluate the effectiveness of certain optics in the dark. I can evaluate the effectiveness of certain flashlights in the dark. Just like at all times I carry an Alpen Wings ED 8X20 in a pouch on my belt I carry a Fenix PD32 flashlight in my pocket. That was an upgrade from Klarus XT1C. Its maximum of the four settings is 315 lumens. It lights the pump house 127 yards away.



Only in the early evening. Normal folks might see. When it's totally dark most folks can see. I met two guys who can see in the dark without a flashlight.

Rich, have you ever had any type of LASIK eye surgery ?

No. What is it?

Laser eye surgery. I asked because I've heard that a lot of people who have had laser surgery loose quite a bit of their night vision for some reason. Sorry if that was a personal question.

One time a pastor asked me,
"Do you want to be the center of attention?"
"No," I told him. Then he told me that was the wrong question.
"Do you mind being the center of attention?"
The answer is still the same. I used to be a high school Sunday School teacher. Automatically, by necessity, I was the center of attention.

Personal questions don't normally bother me.

The great Ringmans posts on optics, can be mostly ignored, as he mentioned he has poor vision,
and only offers a translation. Too bad he posts here, that is the way I see it.

I had Lasik done 6 years ago. My pupils dilate to 8mm when it gets dark. The doctor had prosthetic lenses put in that have a coating that cuts down on the glare. He was afraid that I would have too much light hitting my eye through my pupils and it would cause a glare problem. I still have to wear sunglasses during the day. I never wore them when I was wearing glasses. I was 47 when I had the Lasik procedure done. If anything, it has improved my night vision because I don't need corrective lenses (glasses) to assist in focusing a sharp image.

Ralph, I'm not a doctor and I am only stating what I've heard. A lot of what you could find out about the risks of laser surgery, or possible risks, is easily found on the net. Just look around alittle. You can start here if you want or not as I really don't care.

http://www.lasikcomplications.com/nightvision.htm

Note how a Doctor cain't fix her Imagination either. Laffin'!

Poor dumb Ringman and MagnumDoosh are always giving Pretend a [bleep] whirl,yet their delusions never pan out in Reality. Though in fairness...they're collective Dumbphucktitude is never not routinely impressive,as an absolute [bleep] minimum.

Why is it that these day Dreaming Do Nothing Dumbphucks,can "know" so much,"do" so much,spend so much time "Outdoors",spend so much time "Shooting",spend so much time "working out" and yet amazingly never have a [bleep] thing other than a [bleep] Rat or a [bleep] Turkey to show for "all" of it,as a best case scenario?!!? Laffin'!

The only thing the Dumb [bleep] shoot is their mouths and Imaginations and that in no particular order. Laffin'! What would be interesting,is for 'em to actually hang pics,so as to quantify which of 'em is the most cross-eyed drooling [bleep] retard. Then the "winner" could rightfully laude them braggin' rights and set the record straight. Re-laffin'!

Best part is,the stupid [bleep] are literally [bleep] dumb enough,to allow their Imaginations to turn their Pretend "real". [bleep] wow +P+!

7mm exit last light. Be a pun to boot,though they's too stupid to savvy.




Coulda been a fluke...so here's another 7mm exit at last light. Someone 'splain to the dumb bastards,that'd be a re-pun.



I've gots me a hunch,that serious bandwidth might could get pixelated with a 7mm exit.(grin)

Cain't know which is funnier,the Do Nothing Dumbphucker's using their Imaginations to concoct "experience","knowledge" and "results"...or their using it to concoct excuses. Laffin'!

Tough [bleep] call.(grin)

Stick, generally I enjoy your posts but this one was pretty much a rambling incoherence...please put some more effort into the next one.

Roy,

I didn't mean to be argumentative; I was just relating my own experience with Lasik. I followed your link and read about some of the problems with night vision as a result of having a Lasik procedure done. I believe my surgeon corrected for that when he removed my organic lenses and replaced them with prosthetic lenses. In addition to eliminating the glare at night (halos, stars, rings...etc) he had them made with vision correction built in as well. So now I have an internal set of corrective lenses that also have an anti-glare coating.

Ralph

Farmboy1,



So corrected to 20/15 is poor vision?

J',

As per always,it were crystalline and concise. Them that do will savvy,them that don't...won't(can't).

Why is it,that them who most fancy themselves as rifle optics mavens(for "reasons" knowed only to them),making Thread after Thread to reiterate their perpetual Dumbphucktitude,just cain't ever get crosshairs glued to any Critters?!? I get a [bleep] kick outta it,as it never ain't not hilarious,to let Ring','Doosh,Savage99,Shefire,Jeff-O and the Do Nothing Gang,continuosly flap their gums about "all" the "particulars" of this and that,only for the sorry dumbphuckers to always come up dry. Hilarious how they can always talk it,yet can never walk it...let alone run it.(grin)

It's admittedly only funny,because they are simply doing the best they can and I appreciate the sanctity of that oblivious humor.

Then for frosting,there's the fact that the herd of them bolted together,couldn't knock the new offa used pair of boots. Please understand that I do not wish to curtail their Imaginations,let alone their Pretend and with luck the hilarity will continue,as they add more of both to yet another Optics discussion(and most hopefully this one).

This [bleep] schit is hilarious,butcha' gotta be careful...because they spook away easily!

Laffin'!










Ringman,

Poor vision is you talking out your azz,thinking noone will know any better.

Bless your heart.

It shortens eye-relief too, and being short just...sucks, yeah, short sucks.

I and my son-in-law missed something. Both my Bushnell 6500 and the Swarovski z5 eye relief do not change with changing the magnification setting.

They say they don't change eye-relief when you crank up the magnification, but, the eye-relief still shortens a little bit and the FOV goes from hundreds of feet to tens of feet.

You got that right.