30mm v 1inch

[dylan5588]

Hi guys, question.....does a 30mm tube transmit more light than a 1 inch tube? both with same size objective lens, I have been told it does not, but comparing two Hawke scopes with 50mm objectives but 30mm and 1 inch tubes, the 30mm seemed to be brighter in low light situations, ie dusk. or is it my eyes trying to justify the extra cost???

Regards Aj

[gbal]

Hi guys, question.....does a 30mm tube transmit more light than a 1 inch tube? both with same size objective lens, I have been told it does not, but comparing two Hawke scopes with 50mm objectives but 30mm and 1 inch tubes, the 30mm seemed to be brighter in low light situations, ie dusk. or is it my eyes trying to justify the extra cost???

Regards Aj

Really it's quality of the lenses but IF lenses are equal quality,and internals are equally well made,the bigger diameter tube won't be worse,and you are probably correct with your impression of the two Hawke scopes.

Gbal

[gun nut]

I have a Z5 (1in tube) and a Z6 (30mm), no discernible difference at dusk to my eye.As Gbal says a good quality scope with a 1" tube will always outperform a middle of the field scope with a 30mm tube.

[5R-Twist]

I was under the impression that a 30mm scope would give you a touch more adjustment at long range.

Please shout me down if im wrong.

Rgds

V

[dylan5588]

I was talking about an "all other things equal scenario! I understand quality of optics is the most important thing, but surely if say a 50mm lens gathers a certain amount of light, then a wider tube would allow that light to pass to your eye more efficiently????

Aj

[1066]

I was under the impression that a 30mm scope would give you a touch more adjustment at long range.

Please shout me down if im wrong.

Rgds

V

 

Yes a 30mm tube will usually give a fair bit more adjustment, important if you are shooting loopy calibres at longer ranges.

[gbal]

Brghtness is a product of Exit Pupil diameter,given by Objective lens diameter divided by magnification,in both 30mm and 1" tubes.

The human eye's pupil size varies from about 2mm in bright sun,to about 7mm in the dark.

If the scope's exit pupil is less than your eye's pupil,light transmission is incomplete

If the scope's exit pupil is more than your eye's pupil,light is 'wasted'-eye just can't "see"it,though your eye need not remain so steady in the scope,which may have some advantage in the field.

 

30 mm is not always brighter-both tubes can have internal lenses greater than 7mm

Some 30mm are just built better/seem brighter.30mm are usually stronger,if heavier.Better coatings,and may have larger internal lenses,or same size lenses,so allowing more vertical adjustment in the larger tube.FFP can also give some advantage over SFP because of the efficient position of internal lenses.

 

Size matters,but not much in the eye of the beholder,other things being equal. . o

|

'------'

( eyes do differ a little,as with most anatomy,but not much in pupil diameter range.)

 

ibal

[CZ Varminter]

If you are after the hawke sidewinder tac 30. I have one ate and I really impressed with it for the money. I have a 30mm tube for adjustment I shoot out to 650 on 10" square steel well with it. I half the half mil dot ret.

 

Any more info wanted mate or advice PM me.

 

All the best

 

CZV

[dylan5588]

Brghtness is a product of Exit Pupil diameter,given by Objective lens diameter divided by magnification,in both 30mm and 1" tubes.

The human eye's pupil size varies from about 2mm in bright sun,to about 7mm in the dark.

If the scope's exit pupil is less than your eye's pupil,light transmission is incomplete

If the scope's exit pupil is more than your eye's pupil,light is 'wasted'-eye just can't "see"it,though your eye need not remain so steady in the scope,which may have some advantage in the field.

 

30 mm is not always brighter-both tubes can have internal lenses greater than 7mm

Some 30mm are just built better/seem brighter.30mm are usually stronger,if heavier.Better coatings,and may have larger internal lenses,or same size lenses,so allowing more vertical adjustment in the larger tube.FFP can also give some advantage over SFP because of the efficient position of internal lenses.

 

Size matters,but not much in the eye of the beholder,other things being equal. . o

|

'------'

( eyes do differ a little,as with most anatomy,but not much in pupil diameter range.)

 

ibal

Thank you Gbal for your detailed reply, I am aware of exit pupil science, this is the scenario..... I have my 50mm objective scope with 30mm tube aimed at a bunny in very low light dusk conditions, without the scope I am having difficulty seeing the afore mentioned bunny clearly, looking through the scope I can see it well enough to be confident in making a clean kill shot, Now if I had an identical scope but with a 1 inch tube would the sight picture look any poorer. assuming the exit pupil diameter was slightly less than my pupil diameter with the 30mm and 1 inch scopes??

[dylan5588]

If you are after the hawke sidewinder tac 30. I have one ate and I really impressed with it for the money. I have a 30mm tube for adjustment I shoot out to 650 on 10" square steel well with it. I half the half mil dot ret.

 

Any more info wanted mate or advice PM me.

 

All the best

 

CZV

Thanks czv, I am not looking to replace any scopes, I have three Hawke scopes, an Eclipse 30 4-16x50 side wheel another the same but 6-20x50 side wheel, and a sport 4x12x44 all adequate for my needs Really good scopes for the money. My original post was just a question that has been rattling around in my head for a while.

Aj

[gbal]

Thank you Gbal for your detailed reply, I am aware of exit pupil science, this is the scenario..... I have my 50mm objective scope with 30mm tube aimed at a bunny in very low light dusk conditions, without the scope I am having difficulty seeing the afore mentioned bunny clearly, looking through the scope I can see it well enough to be confident in making a clean kill shot, Now if I had an identical scope but with a 1 inch tube would the sight picture look any poorer. assuming the exit pupil diameter was slightly less than my pupil diameter with the 30mm and 1 inch scopes??

The science applies to the scenario.Since tube diameter per se does not affect light transmission,if the two scopes are otherwise identical ,the 30 mm and 1" tubes have the same light transmission,and the sight picture would not look any poorer.

Gbal

[dylan5588]

The science applies to the scenario.Since tube diameter per se does not affect light transmission,if the two scopes are otherwise identical ,the 30 mm and 1" tubes have the same light transmission,and the sight picture would not look any poorer.

Gbal

Many thanks again,

Aj