The difference between "f-ratio" and "aperture"

joe mama · Feb 20, 2008

There is often a lot of confusion between these two quantities, leading to the oft made comment "f/2 = f/2 = f/2". So, I'd like to clear them up.

The aperture is the diameter of a physical opening in the lens that allow light through. It is the size of the aperture that determines how much light passes through the lens -- not the size of the FE (front element).

The f-ratio is the ratio of the FL (focal length) and the aperture, and is a measure of the intensity of the light, not the amount of the light. For example, a 100mm lens with an aperture of 50mm has an f-ratio of 100mm / 50mm = f/2. Like wise, a 100mm lens at f/2 has an aperture of 100mm / 2 = 50mm.

Thus, lenses with the same f-ratio have the same intensity of light, but do not admit the same amount of light. In other words, a lens at f/2 will have the same intensity of light regardless of the size of the sensor, but the same amount of light will not fall on the sensor.

Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all have the same intensity of light, and thus the same exposure. However, the amount of light that falls on the sensors is quite different, and thus the reason that the noise will be different, given the same design and efficiency of sensor.

However, 50mm f/4 on 35mm FF, 30mm f/2.5 on 1.6x, and 25mm f/2 on 4/3 will not have the same intensity of light, but will have the same total amount of light, since the apertures are all the same (50 / 4 = 30 / 2.5 = 25 / 2 = 12.5mm). To compensate for the different intensity of light (and thus different exposures), the ISOs must be adjusted to give the same apparent exposure . And, again, since the total light is the same, then, if the sensors have the same design and efficiency, the noise will be the same, even though the ISOs are different. Also, as a corallary, for the same perspective and AOV, the DOFs will also be the same for the same aperture.

It is for that reason that "f/2 = f/2 = f/2" is misleading, just as saying "50mm = 50mm = 50mm" is misleading. Both statements, taken out of context, lead to incorrect conclusions. For systems with different sensor sizes, you adjust the FL to get the same AOV, you adjust the f-ratio by the same amount to get the same total amount of light (and DOF), and you adjust the ISO to get the same apparent exposure (and thus same total noise for sensors with the same design and efficiency).

For a lot more on this:

http://www.josephjamesphotography.com/equivalence/

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

nickleback · Feb 20, 2008

I agree with your conclusion, but you take a number of wrong turns to get there.

joe mama said:
The aperture is the diameter of a physical opening in the lens that
allow light through.

The aperture is the apparent diameter of the aperture as seen through the front of the lens (aka the entrance pupil). It's quite possible to have a physically smaller aperture appear larger.

joe mama said:
It is the size of the aperture that determines
how much light passes through the lens -- not the size of the FE
(front element).

However, the size of the front element cannot be smaller than the entrance pupil. On long telephoto lenses the front element is typically the the size of the entrance pupil at max aperture.

joe mama said:
Thus, lenses with the same f-ratio have the same intensity of light,
but do not admit the same amount of light.

Lenses of the same f-ratio admit the same amount of light, too. Otherwise a 35mm f/2 and a 200mm f/2 for the same format won't have the same exposure.

joe mama said:
In other words, a lens at
f/2 will have the same intensity of light regardless of the size of
the sensor, but the same amount of light will not fall on the sensor.

For the same size sensor, absolutely wrong. You haven't stated an assumption that you are comparing different sensor sizes, yet.

joe mama said:
Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all
have the same intensity of light, and thus the same exposure.
However, the amount of light that falls on the sensors is quite
different, and thus the reason that the noise will be different,
given the same design and efficiency of sensor.

This is correct, but that's due to the size of the sensors. All of the stuff above it is misleading at best.

joe mama said:
However, 50mm f/4 on 35mm FF, 30mm f/2.5 on 1.6x, and 25mm f/2 on 4/3
will not have the same intensity of light, but will have the same
total amount of light

Again correct, because the size of the sensors is different.

joe mama said:
Also, as a corallary, for the same perspective and AOV,
the DOFs will also be the same for the same aperture.

Correct again.

joe mama said:
It is for that reason that "f/2 = f/2 = f/2" is misleading, just as
saying "50mm = 50mm = 50mm" is misleading.

Agreed. I just wish you didn't make so many mistakes before stating it.

joe mama said:
For systems with
different sensor sizes, you adjust the FL to get the same AOV, you
adjust the f-ratio by the same amount to get the same total amount of
light (and DOF), and you adjust the ISO to get the same apparent
exposure (and thus same total noise for sensors with the same design
and efficiency).

Correct.

--
Seen in a fortune cookie:
Fear is the darkroom where negatives are developed

rgmoore · Feb 20, 2008

nickleback said:
The aperture is the apparent diameter of the aperture as seen through
the front of the lens (aka the entrance pupil). It's quite possible
to have a physically smaller aperture appear larger.

Or vice versa. On retrofocus lenses, the front segment of the lens (i.e. the elements in front of the physical aperture) has a net negative power, so it makes the aperture appear smaller than its actual size.

nickleback said:
However, the size of the front element cannot be smaller than the
entrance pupil. On long telephoto lenses the front element is
typically the the size of the entrance pupil at max aperture.

Also not quite true. The pupil size isn't necessarily related to the size of the largest element. A true telecentric lens, for instance, has an infinitely large pupil, and many of the near-telecentric lenses designed to minimize peripheral light falloff on digital cameras have exit pupils larger than their rear elements. The problem is that you get vignetting at long distances. That's obviously not a major issue for the exit pupil, since you're unlikely to view it from a long distance. A lens with an entrance pupil smaller than its front element will vignette at infinity focus, but it may be a usable design for a dedicated macro lens.
--

As with all creative work, the craft must be adequate for the demands of expression. I am disturbed when I find craft relegated to inferior consideration; I believe that the euphoric involvement with subject or self is not sufficient to justify the making and display of photographic images. --Ansel Adams

Ray Maines · Feb 20, 2008

After two Martinis I can't make any sense of your post. I'm sure you know what you're talking about but I don't have much of a clue. Maybe if I read it again tomorrow it will all come clear but it's not working for me tonight.

I'm thinking that if I use a f/1.8 lens I'll be able to shoot a picture in lower light, or at lower ISO, than if I shot the same picture with a f/2.8 or f/3.5 max aperture lens. Beyond that, what do I really need to know?

Thanks for your input and thanks for overlooking my stupidity.

--

joe mama · Feb 20, 2008

Ray Maines said:
After two Martinis I can't make any sense of your post. I'm sure you
know what you're talking about but I don't have much of a clue.
Maybe if I read it again tomorrow it will all come clear but it's not
working for me tonight.

...Martinis are bad for you. On the other hand, the dangers of crack are largely exaggerated. : )

Ray Maines said:
I'm thinking that if I use a f/1.8 lens I'll be able to shoot a
picture in lower light, or at lower ISO, than if I shot the same
picture with a f/2.8 or f/3.5 max aperture lens. Beyond that, what
do I really need to know?

The lower the f-ratio, the brighter the image. However, a brighter image on a smaller sensor does not necessarily collect more light than a dimmer light on a larger sensor. As it turns out, if you multiply the f-ratio by the same number you multiply the FL by to get the same framing (this number is called the FM -- "focal multiplier", more commonly called the "crop factor"), then you will collect the same amount of light for the same shutter speed. To get the same shutter speed, you will need to multiply the ISO by the square of the FM.

For example: 25mm f/2 ISO 100 on 4/3 collects the same amount of light as 50mm f/4 ISO 400 on 35mm FF, but the light is more spread out over a larger area for the 35mm FF sensor, so it is less intense. However, by upping the ISO the same 2 stops as the f-ratio, the apparent exposures are the same, and thus, if the sensors have the same efficiency, the noise will also be the same.

Ray Maines said:
Thanks for your input and thanks for overlooking my stupidity.

A lack of understanding is not evidence of stupidity, especially if that lack of understanding is the result of a confusingly worded post. : )

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

joe mama · Feb 20, 2008

nickleback said:
nickleback said:

The aperture is the diameter of a physical opening in the lens that
allow light through.

Click to expand...

nickleback said:
The aperture is the apparent diameter of the aperture as seen through
the front of the lens (aka the entrance pupil). It's quite possible
to have a physically smaller aperture appear larger.

I don't understand what you're saying here. For example, is the aperture at 100mm f/2 equal to 100mm / 2 = 50mm, no?

nickleback said:
nickleback said:

It is the size of the aperture that determines
how much light passes through the lens -- not the size of the FE
(front element).

Click to expand...

nickleback said:
However, the size of the front element cannot be smaller than the
entrance pupil. On long telephoto lenses the front element is
typically the the size of the entrance pupil at max aperture.

However, while the size of the FE approaches the size of the aperture at long FLs, it is wildly different at shorter FLs. For example, the 35 / 1.4L has a max aperture of 35mm / 1.4 = 25mm which is significantly smaller than the diameter of the FE.

nickleback said:
nickleback said:

Thus, lenses with the same f-ratio have the same intensity of light,
but do not admit the same amount of light.

Click to expand...

nickleback said:
Lenses of the same f-ratio admit the same amount of light, too.
Otherwise a 35mm f/2 and a 200mm f/2 for the same format won't have
the same exposure.

I should have been more clear that I was speaking of the same framing for the same perspective on different sensors from the beginning of the post. My bad.

nickleback said:
nickleback said:

In other words, a lens at f/2 will have the same intensity of light
regardless of the size of the sensor, but the same amount of light
will not fall on the sensor.

Click to expand...

nickleback said:
For the same size sensor, absolutely wrong. You haven't stated an
assumption that you are comparing different sensor sizes, yet.

I should have appended "...unless the sensors are the same size" to the end of my sentence. I had thought it was clear that I was talking about different sized sensors at this point of the post.

nickleback said:
nickleback said:

Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all
have the same intensity of light, and thus the same exposure.
However, the amount of light that falls on the sensors is quite
different, and thus the reason that the noise will be different,
given the same design and efficiency of sensor.

Click to expand...

nickleback said:
This is correct, but that's due to the size of the sensors. All of
the stuff above it is misleading at best.

Why is it misleading? It was clearly stated that the sensor sizes were different and with the clear implication that the sensor size was responsible for this.

nickleback said:
nickleback said:

However, 50mm f/4 on 35mm FF, 30mm f/2.5 on 1.6x, and 25mm f/2 on 4/3
will not have the same intensity of light, but will have the same
total amount of light

Click to expand...

nickleback said:
Again correct, because the size of the sensors is different.

Again, I mentioned three different sensor sizes.

nickleback said:
nickleback said:

It is for that reason that "f/2 = f/2 = f/2" is misleading, just as
saying "50mm = 50mm = 50mm" is misleading.

Click to expand...

nickleback said:
Agreed. I just wish you didn't make so many mistakes before stating it.

I don't see any mistakes, aside from not being more clear earlier on that I was considering the same framing for the same perspective. However, it was clear from what I wrote that the sensor sizes are different (35mm FF, 1.6x, 4/3).

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

bevanburns · Feb 20, 2008

joe mama said:
Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all
have the same intensity of light, and thus the same exposure.
However, the amount of light that falls on the sensors is quite
different, and thus the reason that the noise will be different,
given the same design and efficiency of sensor.

I'm still confused on this. It's been a while since I've done any higher level math though. Shouldn't sensor size have nothing to do with noise at the same ISOs? The f-ratio determines the amount of light falling per unit of area, so a lens at f/2.8 and 300mm is projecting the same amount of light per square inch as a 50mm lens at 2.8. If you're using the same sensor, just a cropped version of it in each camera, wouldn't each of those lenses at the same aperture give you exactly the same exposure and the same noise?

Bevan

Silverback1988 · Feb 20, 2008

So JOE...
If we must take the photograph of people,
Say 3 row of 30 people (10 people in each row)
And we want to have their face in focus.
With the same amount of light,
Do the lower format like 4/3 have the benefit on this case ?

Thanks for the info.
And your EQUIVALENCY THEORY is very helpful.
I hope I will fully understand what you mean.

Brian

Jay Turberville · Feb 20, 2008

nickleback said:
Lenses of the same f-ratio admit the same amount of light, too.
Otherwise a 35mm f/2 and a 200mm f/2 for the same format won't have
the same exposure.

This is simply incorrect. A 100mm f/2 lens will admit more light than a 50mm f/2 lens - even though each will provide the same light intensity and exposure at the sensor. The 100mm lens admits four times the light but has twice the magnification. But the image it forms is twice as large linearly. That's one of the basic features of the longer focal length - higher magnification. That extra 2x magnification exactly compensates for the difference in how much more light the 100mm lens with a larger aperture lets in. So the lens admits more light while still providing the same exposure. That's the "magic" of f-numbers.

--
Jay Turberville
http://www.jayandwanda.com

joe mama · Feb 20, 2008

Silverback1988 said:
So JOE...
If we must take the photograph of people,
Say 3 row of 30 people (10 people in each row)
And we want to have their face in focus.
With the same amount of light,
Do the lower format like 4/3 have the benefit on this case ?

No. All formats are equivalent for such a scenario, given the same efficiency of sensor, the same number of pixels, and glass sharp enough to resolve the pixels.

Silverback1988 said:
Thanks for the info.
And your EQUIVALENCY THEORY is very helpful.
I hope I will fully understand what you mean.

Modern DSLRs have nearly the same efficiency of sensor, so that's almost a non-issue anymore, except in situations where one can sacrifice shutter speed or DOF rather than upping the ISO to capture the image.

However, the differences in the pixel counts and the quality of the glass are still important considerations, and it's on the glass quality that 4/3 proponents often make the claim that 4/3 is superior. However, one must also realize that for the same pixel count, a sensor that is half the size must have glass that is twice as sharp merely to maintain parity. So, while glass is an issue, just as the FLs, f-ratios, and ISOs are all different on different systems to capture an equivalent image, the quality of the glass also can be / needs to be different by the same factor.

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

joe mama · Feb 20, 2008

bevanburns said:
bevanburns said:

Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all
have the same intensity of light, and thus the same exposure.
However, the amount of light that falls on the sensors is quite
different, and thus the reason that the noise will be different,
given the same design and efficiency of sensor.

Click to expand...

bevanburns said:
I'm still confused on this. It's been a while since I've done any
higher level math though. Shouldn't sensor size have nothing to do
with noise at the same ISOs?

Well, that's the whole point. If the total amount of light collected is the same, and the sensors have the same efficiency, then the size of the sensor plays no role in the noise.

bevanburns said:
The f-ratio determines the amount of
light falling per unit of area, so a lens at f/2.8 and 300mm is
projecting the same amount of light per square inch as a 50mm lens at
2.8. If you're using the same sensor, just a cropped version of it in
each camera, wouldn't each of those lenses at the same aperture give
you exactly the same exposure and the same noise?

No. Noise has two sources: shot noise (from the light itself, and is the dominant source of noise) and read noise (from the sensor and supporting hardware). The more light that is collected, the less the noise. Well, that's technically incorrect. When people say "noise", they mean NSR (Noise to Signal Ratio). More light means more noise, but a smaller NSR.

So, the sensor that collects more light, presuming the same efficiency (and thus the same read noise) will have less noise. But, for equivalent images (same perspective, same FOV, same DOF, same shutter speed, and same output size), the total collected light is the same, so the the noise will be the same (again, assuming the same efficiency of sensor).

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

joe mama · Feb 20, 2008

Jay Turberville said:
Jay Turberville said:

Lenses of the same f-ratio admit the same amount of light, too.
Otherwise a 35mm f/2 and a 200mm f/2 for the same format won't have
the same exposure.

Click to expand...

Jay Turberville said:
This is simply incorrect. A 100mm f/2 lens will admit more light
than a 50mm f/2 lens - even though each will provide the same light
intensity and exposure at the sensor. The 100mm lens admits four
times the light but has twice the magnification. But the image it
forms is twice as large linearly. That's one of the basic features
of the longer focal length - higher magnification. That extra 2x
magnification exactly compensates for the difference in how much more
light the 100mm lens with a larger aperture lets in. So the lens
admits more light while still providing the same exposure. That's
the "magic" of f-numbers.

I should have been more clear in the OP that I was talking about the same perspective and framing. In the example that follows, I am considering a 100mm lens and 50mm lens on the same size sensor, which was not the example in the OP:

A 100mm lens at f/2 has an aperture of 100mm / 2 = 50mm, whereas a 50mm lens at f/2 has an aperture of 50mm / 2 = 25mm. Thus, the 100mm lens admits four times the light.

However, it is twice as far away for the same framing, so the light is 1/4 as intense. Thus four times the amount of light that is 1/4 as intense comes out to the same total amount of light for the same framing, and thus the same exposure.

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

Silverback1988 · Feb 20, 2008

So, the smaller sensor with the same number of pixel
require sharper glass.

Then we rather have the bigger sensor,
so we don't need push the glass to much.

Is it right ?

joe mama · Feb 20, 2008

Silverback1988 said:
So, the smaller sensor with the same number of pixel
require sharper glass.

Then we rather have the bigger sensor,
so we don't need push the glass to much.

Is it right ?

Right on the money! Now, there's a catch: glass is not uniformly sharp across the entire frame. Canon's UWAs (ultra-wide angles), for example, take a hard dive in the exterme corners compared to 4/3 glass. Thus, Canon's UWAs will deliver a sharper image in the center on 35mm FF (since it has more pixels and can take advantage of this), but a softer image in the extreme corners, with UWAs.

So, while 4/3 glass is not twice as sharp as Canon's 35mm FF glass everywhere in the image circle, it is more than twice as sharp on the edges for some UWAs, and where the boundry between corner and center lies must be taken on a lens by lens basis.

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

Silverback1988 · Feb 20, 2008

OK I get it about UWA sharpness in the extreme corner.

So benefit come to the smaller sensor (say 4/3) when it come to sharpness in the corner.

But...
when we want the same angle of view at the same distance,
28mm with 35mm FF
so 14mm glass with the 4/3.

The barrel distortion may occured more heavily in the 14mm.

Correct me if I were wrong.

Thanks for sharing the info.

joe mama · Feb 20, 2008

Silverback1988 said:
OK I get it about UWA sharpness in the extreme corner.

So benefit come to the smaller sensor (say 4/3) when it come to
sharpness in the corner.

Well, I didn't say that! : ) Some of the current 4/3 lenses are better than Canon's UWAs in the corners. I didn't mean to imply that it was an advantage to the format, just an advantage for some of the current lenses. The Nikon 14-24 / 2.8 on a 35mm FF sensor, for example, is the best UWA available.

Silverback1988 said:
But...
when we want the same angle of view at the same distance,
28mm with 35mm FF
so 14mm glass with the 4/3.

The barrel distortion may occured more heavily in the 14mm.

Correct me if I were wrong.

This I know nothing about one way or another. There may be issues with designing lenses twice as wide than 35mm FF for 4/3 to get the same FOV that cause issues related to a smaller sensor. However, I don't know about any of that. I do know that the Olympus 7-14 / 4 has significantly less distortion than the Canon 16-35 / 2.8L II, but is not as good as the Sigma 12-24 / 4.5-5.6. So, I think things such as distortion must be taken on a lens by lens basis, and are not a function of the sensor size.

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

Silverback1988 · Feb 21, 2008

I mean to get the same AOV, smaller format need a smaller mm.

For instance 28mm glass in 5D has the same AOV with 14mm in Olympus 4/3.

If Canon make the 4/3 format too...

So Canon will hardly make less barrel distortion in 14mm than in their 28mm glass.
No ?

Thanks in advance JOE for keep replying me.

joe mama · Feb 21, 2008

Silverback1988 said:
I mean to get the same AOV, smaller format need a smaller mm.

For instance 28mm glass in 5D has the same AOV with 14mm in Olympus 4/3.

Yes. FOV, however, is a bit more complicated as the aspect ratios are different. To get the same FOV, 35mm FF needs to be framed 8% wider, and then needs to crop 5.5% of the image from the left and right sides.

Silverback1988 said:
If Canon make the 4/3 format too...

Never gonna happen. Canon's tied up with 1.6x, and probably debating the future of 1.3x.

Silverback1988 said:
So Canon will hardly make less barrel distortion in 14mm than in
their 28mm glass.
No ?

Not a clue.

Silverback1988 said:
Thanks in advance JOE for keep replying me.

No worries. Others might have the same questions. : )

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

Silverback1988 · Feb 21, 2008

Now I have 30D and waiting for the next 5D (man... it's too long)

Beside that, I have a 1/1.8" pocket camera (Sony V1) just like Canon G series.
I like the small for I could have it all along with me most of the time.
BUT...
I hate it's sensitivity due small PIXEL SIZE.
I found I often go to ISO 800 to gain speed... and it is noisy.
5 MP in 1/1.8"

If I want it has at least like 400D's Pixel Size.
It count approx only 1 MP left.
Is that correct?

Will the ISO act like 400D's ISO.

Thanks so much.
And see you again.

Brian

JoePhoto · Feb 21, 2008

YOU ARE GONNA GIVE ALL "JOE'S" A BAD NAME !!!

(Are you really from "earth" ???)

joe mama said:
There is often a lot of confusion between these two quantities,
leading to the oft made comment "f/2 = f/2 = f/2". So, I'd like to
clear them up.

The aperture is the diameter of a physical opening in the lens that
allow light through. It is the size of the aperture that determines
how much light passes through the lens -- not the size of the FE
(front element).

The f-ratio is the ratio of the FL (focal length) and the aperture,
and is a measure of the intensity of the light, not the amount of
the light. For example, a 100mm lens with an aperture of 50mm has an
f-ratio of 100mm / 50mm = f/2. Like wise, a 100mm lens at f/2 has an
aperture of 100mm / 2 = 50mm.

Thus, lenses with the same f-ratio have the same intensity of light,
but do not admit the same amount of light. In other words, a lens at
f/2 will have the same intensity of light regardless of the size of
the sensor, but the same amount of light will not fall on the sensor.

Thus, 50mm f/2 on 35mm FF, 30mm f/2 on 1.6x, and 25mm f/2 on 4/3 all
have the same intensity of light, and thus the same exposure.
However, the amount of light that falls on the sensors is quite
different, and thus the reason that the noise will be different,
given the same design and efficiency of sensor.

However, 50mm f/4 on 35mm FF, 30mm f/2.5 on 1.6x, and 25mm f/2 on 4/3
will not have the same intensity of light, but will have the same
total amount of light, since the apertures are all the same (50 / 4 =
30 / 2.5 = 25 / 2 = 12.5mm). To compensate for the different
intensity of light (and thus different exposures), the ISOs must be
adjusted to give the same apparent exposure . And, again, since the
total light is the same, then, if the sensors have the same design
and efficiency, the noise will be the same, even though the ISOs are
different. Also, as a corallary, for the same perspective and AOV,
the DOFs will also be the same for the same aperture.

It is for that reason that "f/2 = f/2 = f/2" is misleading, just as
saying "50mm = 50mm = 50mm" is misleading. Both statements, taken
out of context, lead to incorrect conclusions. For systems with
different sensor sizes, you adjust the FL to get the same AOV, you
adjust the f-ratio by the same amount to get the same total amount of
light (and DOF), and you adjust the ISO to get the same apparent
exposure (and thus same total noise for sensors with the same design
and efficiency).

For a lot more on this:

http://www.josephjamesphotography.com/equivalence/

--
--joe

http://www.josephjamesphotography.com
http://www.pbase.com/joemama/

--
Thanks for reading .... JoePhoto

( Do You Ever STOP to THINK --- and FORGET to START Again ??? )

The difference between "f-ratio" and "aperture"

Forum Pro

Forum Pro

Senior Member

Senior Member

Forum Pro

Forum Pro

Member

Leading Member

Forum Pro

Forum Pro

Forum Pro

Forum Pro

Leading Member

Forum Pro

Leading Member

Forum Pro

Leading Member

Forum Pro

Leading Member

Veteran Member

Similar threads

Keyboard shortcuts