30 mm vs. 1" scopes

[HiredHand]

Oh, 34mm tube are the new hotness...

 

[MoBoost]

Oh, 34mm tube are the new hotness...

Seems like it, 34mm is coming ... I had a pleasure to look through 8-80x56 MarchX (yes 80X <-- that thing blows ANY spotting scope clear out of the water ... into the orbit).

So from now on, unless someone mounts 150mm refractor on their rifle - I'm not impressed - it HAS to look like AN/PVS-2!

 

[Ignored Member]

ummmm.... I'm confused....

 

[MoBoost]

ummmm.... I'm confused....

Everybody should be by now

Here is the original question:

Is the big benefit of a 30 mm scope light gathering characteristics? If you have a high quality 1" scope,is it worth it to replace it with a 30 mm,all other things being equal? I'm using it on a long range precision/varmint rifle.

Here is the CORRECT answer, AKA first reply:

I believe a 30mm tube gives you greater elevation adjustment over a 1" tube.

Btw, scopes don't gather light. They transmit light which is controlled by the glass and the coatings used on the glass. Take some of your current scopes ouside at night and see how much light they transmit its pretty amazing.

Quick explanation on light transmission here :
http://www.schmidtbender.com/facts_light.shtml

Everything else is white noise known as "tha interwebz". Please join!

 

[HiredHand]

Roflmao! MoBoost, you got it right! If you don't have the Hubble mounted on there then you don't have enough scope.

 

[HMFIC]

Oh, common ... this IS going from bad to worse:

"The principal advantages of the 30mm tube are added strength and increased adjustment range for windage and elevation. For example, the M8-12X (1" maintube) has a total elevation adjustment of 51 minutes. The Mark-4 M1-10X (30mm maintube) has 90 minutes. The percentage of light passing through a scope is a function of lens coating and optical design, and has nothing to do with tube diameter."
Source - Leupold.

I'm man enough to admit when I'm wrong. You're correct about tube size and light transmission.
We agree on FOV already.

Here's a good little article that explains things too:

http://www.opticstalk.com/riflescope-school_topic5027.html

 

[redmax51]

Oh, common ... this IS going from bad to worse:

"The principal advantages of the 30mm tube are added strength and increased adjustment range for windage and elevation. For example, the M8-12X (1" maintube) has a total elevation adjustment of 51 minutes. The Mark-4 M1-10X (30mm maintube) has 90 minutes. The percentage of light passing through a scope is a function of lens coating and optical design, and has nothing to do with tube diameter."
Source - Leupold.

^^^This is what I was looking for.Thanks to everyone for an interesting thread.

 

[NikatKimber]

Oh, common ... this IS going from bad to worse:

"The principal advantages of the 30mm tube are added strength and increased adjustment range for windage and elevation. For example, the M8-12X (1" maintube) has a total elevation adjustment of 51 minutes. The Mark-4 M1-10X (30mm maintube) has 90 minutes. The percentage of light passing through a scope is a function of lens coating and optical design, and has nothing to do with tube diameter."
Source - Leupold.

Notice that bolded part. It doesn't say the *amount* of light, but the percentage.

I will say this though, the light concentration is not high enough to demand a larger tube to transmit it. The amount of light going through the scope depends on how much is transmitted by the objective lens.

Correct. It doesn't determine FOV - but it can "choke" it like on very old low magnification scope like Wever 3-30: the tube was so long and magnification so small that the objective actually appeared in FOV.

The same way the tube diameter can.

Whether we disagree or agree, suffice it to say that with optics, like guns, cars, or anything else, it's all a compromise. There's nothing easy that can be done to increase any part of the equation without giving up somewhere else.

Larger tube diameter has its benefits (what they are doesn't matter here), but sacrifices on weight, and the larger lenses required are more expensive. Which is why many cheaper scopes (and some expensive ones) use 1" tubes because they can maintain or improve optical quality.

For any specific scope specs and geometry, there will be specific dimensions ideal for it.

 

[Perplexed]

I could easily be wrong, but... isn't that a lens cover in place on the front of that scope?

 

[HiredHand]

I could easily be wrong, but... isn't that a lens cover in place on the front of that scope?

You're right but it has a pin hole to allow a small amount of light through for daytime use.