Light transmission

[shoot4fun]

Although that exit pupil factor can easily be calculated for any optical device it can't make adjustments for how the coating inside of the optic is done. Also, every makers HD glass is of different quality even if it comes from the same glass producer. All optics manufacturers use coatings but not all coatings are the same. Just saying "fully multi-coated HD glass" is not enough. With top quality optics the last, and most important, factor is the peepers looking thru them. My older Leica 10x50 BA binoculars allowed me for many years to sit on a stand and view deer out past 100 yards in pitch-dark if there was just a little moonlight. The last year or two that isn't the case. Same with some very nice scopes I own. Did they go bad? Of course not! It's my EYES!

 

[Turbulent Turtle]

Actually, you do not need to have increased wall thickness to get added strength, just the fact that the tube has a wider diameter makes it inherently stronger than a 1inch tube. If you make the walls thicker, you rob from the increased adjustment range.

In optics, the larger the lens the greater the amount of light going through it, hence the difference between a 40mm objective and a 56mm objective. It's the same with internal lenses. So the next step up is the 34-35mm range with larger internal lenses for the same adjustment range, usually. Barrel nut was absolutely correct in comparing to camera lenses, and that's why you see sports photographer with ginormous lenses with yuge internal lenses to be able to get enough light to the sensor to stop the action at a high shutter speed and for that you need a lot of light. Currently for my D-SLR, the fastest lens I have is a F1.8, but there are bigger faster lenses going all the way to F1.2 or even faster. I have heard the fastest lens is actually a F0.95 (must be yuge.)

 

[JRS]

Actually, you do not need to have increased wall thickness to get added strength, just the fact that the tube has a wider diameter makes it inherently stronger than a 1inch tube. If you make the walls thicker, you rob from the increased adjustment range.

In optics, the larger the lens the greater the amount of light going through it, hence the difference between a 40mm objective and a 56mm objective. It's the same with internal lenses. So the next step up is the 34-35mm range with larger internal lenses for the same adjustment range, usually. Barrel nut was absolutely correct in comparing to camera lenses, and that's why you see sports photographer with ginormous lenses with yuge internal lenses to be able to get enough light to the sensor to stop the action at a high shutter speed and for that you need a lot of light. Currently for my D-SLR, the fastest lens I have is a F1.8, but there are bigger faster lenses going all the way to F1.2 or even faster. I have heard the fastest lens is actually a F0.95 (must be yuge.)

I have an 85MM f/1.2 II that is the size of a large grapefruit

 

[Ggmac]

When you look at scope adverts , look at the wording :
First is coated lenses
Second is fully coated lenses
Last is fully multi coated lenses
As to coatings most companies will tell you it's proprietary.

 

[Turbulent Turtle]

I have an 85MM f/1.2 II that is the size of a large grapefruit

I'm sure. And probably very heavy also. My f/1.8 is a 35mm lens, which is the DX equivalent of a 50mm prime lens in 35mm parlance.

When needed, and it very rare now, I just boost the ISO if needed. These D-SLRs do a great job of reducing or eliminating noise. I like the smaller format for the weight and bulk savings. (And the cost saving is good too.)

 

[JRS]

I'm sure. And probably very heavy also. My f/1.8 is a 35mm lens, which is the DX equivalent of a 50mm prime lens in 35mm parlance.

When needed, and it very rare now, I just boost the ISO if needed. These D-SLRs do a great job of reducing or eliminating noise. I like the smaller format for the weight and bulk savings. (And the cost saving is good too.)

My 85MM 1.2 weighs 2 pounds 2 ounces. My 85MM 1.8 weighs 14 ounces. The 1.2 uses a 72MM filter, as does my 35MM 1.4, the 1.8 uses a 58MM filter.

 

[Turbulent Turtle]

My 85MM 1.2 weighs 2 pounds 2 ounces. My 85MM 1.8 weighs 14 ounces. The 1.2 uses a 72MM filter, as does my 35MM 1.4, the 1.8 uses a 58MM filter.

Ah ha! You're a Canon man. That 85 f/1.2 is the Canon EF 85mm f/1.2L II USM lens, isn't it? I'm a Nikon man myself, going back to the 1970s. Equipment sure has changed since.

 

[JRS]

Ah ha! You're a Canon man. That 85 f/1.2 is the Canon EF 85mm f/1.2 II USM lens, isn't it? I'm a Nikon man myself, going back to the 1970s. Equipment sure has changed since.

Yes I am, and yes it is I started with Nikon decades ago, then moved on to Canon. I still have a couple of film cameras

 

[Spike A]

Any one even develop film anymore ? ... pb find that place right next to the 8 tracks.. just giving you guys a hard time

 

[Ledd Slinger]

Anyone wanna talk about rifescopes?

 

[pemo]

I use Schmidt & Bender Zenith 3-12x50 and Meopta R2 2.5-15x56 for night time wild boar hunting in Sweden.

Only permanent light at the feeder is permitted, no lights on the rifle, but where I hunt there are no functional lights at the feeders. So I am dependant on top glass in times of low levels of moon light. The boars are often more alert at full moon light levels, so you kinda wanna go out at the lowest moon light levels your glass can handle, in order to get the pigs out on the feeding area in the first place.

The new Meopta R2 and the "older" S&B Zenith are roughly the same price. Meopta comes with a 30yr warranty, incl illumination electronics, in Europe whereas S&B just have a very good reputation for taking good care of their customers.

I am very satisfied with these two scopes

Meopta

S&B 3-12x50 on my 9.3x62 Mauser

 

[Spike A]

coyote hunting around is here is done in the winter over snow for the most part, so even on a half moon i have discovered with good glass one can see very well....

 

[Turbulent Turtle]

Anyone wanna talk about rifescopes?

Well, excuuuuuuuuusssee me. We are talking about light transmission here, (look at the thread title,) and we are establishing what is needed for optimum light. My most recent point was that bigger lenses transmit more light and I gave real life examples. Lens coating will reduce the amount of light lost in the lenses, but larger lenses will allow more light through. You still want your bigger lenses multicoated, of course.

 

[Barlow]

Check out on the www, "Scope, Optics & Ballistic info & faqs". It's a long but informative read. Barlow

 

[Ledd Slinger]

I use Schmidt & Bender Zenith 3-12x50 and Meopta R2 2.5-15x56 for night time wild boar hunting in Sweden.

Only permanent light at the feeder is permitted, no lights on the rifle, but where I hunt there are no functional lights at the feeders. So I am dependant on top glass in times of low levels of moon light. The boars are often more alert at full moon light levels, so you kinda wanna go out at the lowest moon light levels your glass can handle, in order to get the pigs out on the feeding area in the first place.

The new Meopta R2 and the "older" S&B Zenith are roughly the same price. Meopta comes with a 30yr warranty, incl illumination electronics, in Europe whereas S&B just have a very good reputation for taking good care of their customers.

I am very satisfied with these two scopes

Meopta

S&B 3-12x50 on my 9.3x62 Mauser

Dont see too many S&L rifles floating around in the states. And almost never see ANY rifle chambered in 9.3x62 Mauser. Very nice

Looks like the same rifle with the stock refinished and new bottom metal. The renovations turned out very nicely

I'm sure that S&B and Meopta R2 rip through the darkness to give you top notch low light performance.

 

[rifleman700]

Well, excuuuuuuuuusssee me. We are talking about light transmission here, (look at the thread title,) and we are establishing what is needed for optimum light. My most recent point was that bigger lenses transmit more light and I gave real life examples. Lens coating will reduce the amount of light lost in the lenses, but larger lenses will allow more light through. You still want your bigger lenses multicoated, of course.

Not true. How does a 56mm objective lens transmit more light through a 30mm tube than a 50MM objective? 30mm is 30mm and only so much light will go through. Lens coatings is the key to image correction and light transmission.

 

[Ledd Slinger]

Partially true rifleman 700, lenses and coatings are the biggest key, but the front objective does play a part as well because it effects the amount of light transmitted to the exit pupil. All glass and coatings being equal, a larger front objective lens will transmit more light to your eye.

We can all agree that Swarovski is one of the best there is when it comes low light performance, if not THE best. Below is a link to an article written by Ron Spomer for Swarovski. Swarovski keeps this posted on their main website in the blog section. It describes in perfect detail how light transmission works through different objective sizes in relation to the exit pupil and completely debunks any of the 'theories' that a 30mm tube transmits more light. This link is straight from the Swarovski Optik website.

http://www.swarovskioptik.com/hunting/blog/RS_tube_size_matters_but_not_much

 

[Turbulent Turtle]

Not true. How does a 56mm objective lens transmit more light through a 30mm tube than a 50MM objective? 30mm is 30mm and only so much light will go through. Lens coatings is the key to image correction and light transmission.

Ledd Slinger answered it correctly, the bigger objective will transmit more light from the outside into the riflescope, than the smaller objective.

 

[rifleman700]

Partially true rifleman 700, lenses and coatings are the biggest key, but the front objective does play a part as well because it effects the amount of light transmitted to the exit pupil. All glass and coatings being equal, a larger front objective lens will transmit more light to your eye.

We can all agree that Swarovski is one of the best there is when it comes low light performance, if not THE best. Below is a link to an article written by Ron Spomer for Swarovski. Swarovski keeps this posted on their main website in the blog section. It describes in perfect detail how light transmission works through different objective sizes in relation to the exit pupil and completely debunks any of the 'theories' that a 30mm tube transmits more light. This link is straight from the Swarovski Optik website.

http://www.swarovskioptik.com/hunting/blog/RS_tube_size_matters_but_not_much

If you read my first post I stated that objective size has little do with light transmission not nothing to do but not as much as some think.

The human eye can only take advantage of so much exit pupil size and the rest is wasted or not utilized.

I did not even want to get into the 30mm discussion about light transmission because that would open up another can of worms.

For coyote hunting I run a Swarovski Z6 2.5-15x44 and it is superb in low light and only has a 44mm objective. The only scope that would come close that I have owned was a S&B Klassik with a 42mm objective.

The S&B 3-27X56 I owned was one of the worst low light scopes I have ever owned.

 

[rifleman700]

Ledd Slinger answered it correctly, the bigger objective will transmit more light from the outside into the riflescope, than the smaller objective.

Scopes are not funnels. It does not work that way.