Scope confusion...

I hope I don't add to your confusion, but I think I have this right.

From what I've learned, you can't foretell the brightness level solely based on the parameters you listed, although they do matter. 

More specifically, even if it's the same manufacturer, they often build various models using different construction methods, and use different lens coatings and/or internal tube coatings on different models.  I think those things also matter.

Now, if you were comparing various models in the "Bushnell Engage" line for instance (they got mentioned in another thread the other day), I think you might be able to get a real answer because you'd probably be comparing apples to apples.  That's not always the case, even if the manufacturer is the same.  It's not that unusual for some mfrs. to offer multiple models that are built differently, built in different factories in different countries, for instance.

If you have some specific makes and models in mind, I think someone might be able to help you more.  Can you supply more details?

That's just my two cents to get the answers rolling in this thread.  I'm perfectly willing to be corrected as necessary. 

Oh, yeah, and here are all those Bushnell Engage scopes listed on one page for your perusal--just pick your 'favorite flavor' and you can read the details about that specific model:

https://www.bushnell.com/Products/Riflescopes?collection=Engage&page=1

Joe of Cyclops videos does a fantastic job reviewing scopes and a number of other things. Pick a few scopes out that you like and look for reviews on them, either by him or others. I personally like Leupolds, all of mine have 40mm adjustable objectives and are 1" tubes. Everyone that peaks thru them cant believe the quality. Every one was under 500 bucks. I bought a 149.95 scope, it was a compact 4-12x44. What a P.O.S. 

If we look at things theoretically, the 50mm scope will be 29% brighter. If the optical path is designed correctly, the tube diameter shouldn't come into play.

Exit pupils are calculated by dividing the objective diameter by the power. In low light, the human eye pupil opens up to about 7mm. So, for things like binoculars, a pair of 7x50 binos (7mm exit) will be a good choice for low light, where a 7x35 (5mm exit) would not.

For your listed choices,

44mm ; 4x =11mm pupil, 16x = 2.75mm pupil.

50mm ; 4x =12.5mm pupil, 16x= 3.125mm pupil

As you can see, at 16x, both pupil sizes are way below the 7mm max for the eye, and therefore, the objective size trumps for brightness (29% for the 50mm) in lower light.

Of course, this is theory, The quality of the glass, and especially the coatings, can make a huge difference, and if the 44mm had much better optics, it could be brighter, and clearer, than a poor quality 50mm.

Thanks to each of you for your help.Price and weight will probably limit me to the 50mm for the max. and I'll just have to try them after I consult the better reviews. I really don't like to send things back and forth ,so I hoped I could just get it right.I need to upgrade some glass to be able to shoot in the summer when the tree canopy is shutting out too much light.I hope to see some accuracy improvements too.Thanx agn.

EricinMaine-

Eric;

One thing you have added which changes everything is that you plan to shoot in summer.

Here's why: Summer, usually brings very bright weather, so your pupil will NOT be 7 mm's (specially if you are over  40 Y.O., it seldom goes over 6).

So, if your pupil is adjusted to a bright day (usually around 2.5-3 mm's), it would take between 20 and 25 minutes of relative darkness to actually adjust to the dark under-trees setting you are referring to. And if you are walking into lit areas to collect targets or anything, your iris will again adjust down real fast. After all, it's their job to protect the inside of the eyes by allowing only the needed amount of light.

So, what you should really be looking into is the  "wiggle room" that the different exit pupils will allow you when shooting.

The REAL difference between using a 30 mm's and a 1" tube, may not be important to you, is that a 30 mm's tube allows for more robust components to be inserted into the scope. Things are not as "miniature" as they need to be in a 1" scope.
For spring-gunners, it usually means better resistance to recoil and vibrations.

If you are thinking of a well established line/brand, then try to locate  a STORE where you can compare both. Try to locate a badly illuminated "target" and compare them.

HTH

HM

I always thought your eyes could not handle much more then 5 exit pupil

You are mostly right.

Trained personnel, of relatively young age, with good preparation (red light for at least 4 hours prior to going out into the dark), can reach the 7 mm's. But it takes some training and a young age.

😉

HM

+1 on what Hector said.

Buying a scope with a 30mm tube often means it is not the bottom line of the manufacturer.

(That's good, but of course, a 1" scope by a top mfctr. most likely is still better than a 30mm of a cheapo-China mfctr. ? ).

The 30mm scope often also allows for a larger turret adjustment range.

So, if you want to shoot long and extreme long distance, and would like to click (dial) your elevation turret to aim dead on the bulls/ quarry with the cross hairs, you'll need a lot of "clicks."

Low and mid-priced scopes often have only about 40 or 50 MOA of adjustment range (12-15 MIL or MRAD) — and that will limit you to 60, 70 yards — depending on the power of the gun and the weight of the pellet you choose.

The largest exit pupil I have noted ,so far, is 4.17 mm. The smallest I have  is 1.17 mm.I have not used the scope with the smaller yet because I saved it for the bench.I haven't set up for 100 yd. and beyond yet.I have a post cut and set at 100 yd.,but no backstop yet.I'll have to wait till Crowbar gets the time 🙂 .

EricinMaine-