f/2.8 vs f/4

BTW, for the original post ChrisBlaze, here's a linky to comparisons on F2.8 vs. F4.0 dude: http://www.pixource.co​m …ws/EF24-105L/samples.html

Wayne MG wrote in post #2269194
Gotcha. Thanks for quick the followup. I just wanted to make sure that your shutter speed was OK for the given focal length, and factored for being on a 1.6 crop camera. Your Tamron is pretty sharp at F4.0 though.

I rarely shoot wide open, I would rather bump the ISO or use a speedlight. Sharpness at f/4 is good, at f/8 it is insane.

Hey Chris,

Is this regarding the choice between the Sigma 70-200mm f/2.8 and the Canon 70-200mm f/4 L?

I have been trying to determine whether the 1 stop difference is going to make a difference for me, considering that most of the time I would be using a long lens like this will be outdoors in daylight.

Tastes Great!!!

chaosbunny wrote in post #2269171
thats windows xp

Whats wrong with XP? you don't own one of those useless mac's do you?


I like my 70-200 F2.8L can't beat it, it is heavier but it still is better in low lights

rabidcow wrote in post #2269165
One at 2.8, the other at 4, not changing shutter speed. Note the softness at 2.8.

Not changing the shutter speed? That is why your image is so dark and underexposed.
That might be the worst comparison example I have seen. Monitors "blink" 60 or more times per second and you're taking a picture of some of its blinks.

You'd need to post 100% crops of a shot of a flat plane to see differences between f2.8 and f4. A frame with objects at different distances would show a better to show at a full frame the background blur, otherwise you need 100% crops.

The most difference you'll see if the amount of light f2.8 will let in for exposure. Going from f4 to f2.8 will allow you to take a shot at iso800 instead of moving up to iso1600.

I believe that rabidcow did exactly what ChrisBlaze asked for. He just wanted a comparison between the two of the exact same shot. It is the easiest way for him to see the difference. If you start adjusting ISO's and what not to get a perfect shot, ChrisBlaze would never see the difference between the two.

Hellashot wrote in post #2269298
Not changing the shutter speed? That is why your image is so dark and underexposed.
That might be the worst comparison example I have seen. Monitors "blink" 60 or more times per second and you're taking a picture of some of its blinks.

You'd need to post 100% crops of a shot of a flat plane to see differences between f2.8 and f4. A frame with objects at different distances would show a better to show at a full frame the background blur, otherwise you need 100% crops.

The most difference you'll see if the amount of light f2.8 will let in for exposure. Going from f4 to f2.8 will allow you to take a shot at iso800 instead of moving up to iso1600.

The underexposure demonstrates the one stop difference. And I am aware of monitor refresh rate, but the scan lines of an LCD are not the same as a CRT. I was just trying to help by giving the OP what he asked for, I was not aware that this was a photo contest.

rabidcow wrote in post #2269197
Are we starting an OS battle here? While we are at it why don't we start an automobile manufacturer battle....

hehehehe...but OS's are more fun!!!

rabidcow wrote in post #2269197
Are we starting an OS battle here? While we are at it why don't we start an automobile manufacturer battle....

Ooh yea... that would be much more fun,

TMR Design wrote in post #2269245
Hey Chris,

Is this regarding the choice between the Sigma 70-200mm f/2.8 and the Canon 70-200mm f/4 L?

I have been trying to determine whether the 1 stop difference is going to make a difference for me, considering that most of the time I would be using a long lens like this will be outdoors in daylight.

Sorta, I trying to decide on either the 70-200mm f/2.8L or the 70-200mm f/4L. I know that the f/4 verison is half the price of the 2.8. But, sometimes I wonder if I will buy the f/4 only to sell it, take a loss, and get 2.8.
People say that you can shoot night sports with f/4 some say you cant. Its hard to decide until I see some sports taken at night with the f/4.

ChrisBlaze wrote in post #2269513
Sorta, I trying to decide on either the 70-200mm f/2.8L or the 70-200mm f/4L. I know that the f/4 verison is half the price of the 2.8. But, sometimes I wonder if I will buy the f/4 only to sell it, take a loss, and get 2.8.
People say that you can shoot night sports with f/4 some say you cant. Its hard to decide until I see some sports taken at night with the f/4.

if you will be shooting sports at night i would definitely get the f2.8.

ed rader

ChrisBlaze wrote in post #2269513
Sorta, I trying to decide on either the 70-200mm f/2.8L or the 70-200mm f/4L. I know that the f/4 verison is half the price of the 2.8. But, sometimes I wonder if I will buy the f/4 only to sell it, take a loss, and get 2.8.
People say that you can shoot night sports with f/4 some say you cant. Its hard to decide until I see some sports taken at night with the f/4.

I can't imagine shooting sports at night with anything less that f/2.8-- even that isn't really enough some times.

ChrisBlaze wrote in post #2269513
People say that you can shoot night sports with f/4

That's only in the newest NFL stadiums.

The difference between shots at 2.8 and 4 will come out in a few different ways...
- when you are trying to capture motion and the shorter exposure time will result in a different effect between the 2.8 and 4
- when you are trying to capture low light and the shutter speed gets longer - and results in camera shake
- bokeh in certain cases that will be more at 2.8
- 2.8 lenses stepped down to 4 will typically produce sharper images.

Its not a given that 2.8 vs 4 images will look different always - it depends on the circumstances and the end result one is trying to achieve.