Am I stupid or is the difference really negligible b/w 2 lenses?

I'm a newbie DSLR user. I've had my 7d for about 6 weeks now. My shutter count is up to about 275. I started out with the prime lens EF 50mm f/1.8 II. I just got the EF 24-105mm f/4L IS USM this weekend. I honestly cannot tell a difference between these two lenses, except for the variable focal range of my newest addition. The picture quality, the AF speed, etc...seems identical. I was also gearing up to buy the EF 70-200 f/4L IS, but didn't because it's out of stock here in Hong Kong. I guess, until I can notice a difference, there should be no more L lenses for me. Any pointers on what to do with the 2 lenses, to be able to notice a difference, or any other advice, I'd greatly appreciate.

set your 50mm to f/1.8 ?
if you wont see a difference then then something wrong

You'll notice a goodly difference between a 70-200 f/4 L IS and a cheaper alternative, the 70-200 is a highly regarded lens and very sharp.

Your 2 lenses are also very good. The thing to remember is that prime lenses are often sharper than zooms due to there being less glass for the light to travel through.

Your 50mm beats the 24-105 at all apertures between f/1.8 to f/3.5 simply because the 24-105 doesn't go that wide.

Frankly, I wouldn't worry about busting a gut to find the differences between the two, rather you should go out shooting with them and find where their strengths lie. Nothing wrong at all with owning both, a lot of people do and the 70-200 would be a fine addition in the future.

agree with mike, ive tested several incarnations and own one of the canon 70-200's
theyre incredible lenses.

These are 2 different lenses for different purposes... they should not be compared. Primes in general have an IQ advantage over zooms, but the 24-105 should be very sharp (at least mine is).

Stop the 24-105mm L down to it's sweet spot between f/5.6 at wider focal lengths and f/8 at the telephoto end to see it's best IQ.

Try to focus the 50 in low light.

SCOTTinNJ wrote in post #12153556
Try to focus the 50 in low light.

Try opening up the 24-105mmL to f/2

275 in 6 weeks? You need to get out more. Apples and Oranges. Do not compare them. Many people have both and enjoy both. Your challenge, should you decide to accept it, is to discover what each lens is best at, for what you do.

Stand 8 feet away from a person and set your 50 to 2.0 then take your 24-105 at 50 and set it to 5.6 and then compare

Oz Visuals wrote in post #12154101
Stand 8 feet away from a person and set your 50 to 2.0 then take your 24-105 at 50 and set it to 5.6 and then compare

What would be the purpose of running an IQ test on two lenses at different apertures?

^+1 same distance from the subject, same fl, different aperture. Of course the other one is going to have more dof.

GreenTreeFrog wrote in post #12153398
I'm a newbie DSLR user. I've had my 7d for about 6 weeks now. My shutter count is up to about 275. I started out with the prime lens EF 50mm f/1.8 II. I just got the EF 24-105mm f/4L IS USM this weekend. I honestly cannot tell a difference between these two lenses, except for the variable focal range of my newest addition. The picture quality, the AF speed, etc...seems identical. I was also gearing up to buy the EF 70-200 f/4L IS, but didn't because it's out of stock here in Hong Kong. I guess, until I can notice a difference, there should be no more L lenses for me. Any pointers on what to do with the 2 lenses, to be able to notice a difference, or any other advice, I'd greatly appreciate.

Switch your camera to back button focusing method.
Get assistant (someone who will walk in front of the camera)
Switch to AI Servo.
As assistant to move something like ten meters from camera.
Focus at 105 by using of one AF point which will be close to assistant face.
Ask assistant to walk fast toward to camera, not straight, but like "drunken sailor" style.
Track and zoom out to 24 your assistant and take pictures by same time.

Repeat the same at 50 1.8 at same F4.

Review your pictures at monitor to see how many will be in focus.

kf095 wrote in post #12154400
Switch your camera to back button focusing method.
Get assistant (someone who will walk in front of the camera)
Switch to AI Servo.
As assistant to move something like ten meters from camera.
Focus at 105 by using of one AF point which will be close to assistant face.
Ask assistant to walk fast toward to camera, not straight, but like "drunken sailor" style.
Track and zoom out to 24 your assistant and take pictures by same time.

Repeat the same at 50 1.8 at same F4.

Review your pictures at monitor to see how many will be in focus.

wow, recruiting people to act like "drunken sailors" to test lens !

RDKirk wrote in post #12154127
What would be the purpose of running an IQ test on two lenses at different apertures?

It will obviously make the pictures look completely different. The nifty excels at large apertures (relatively speaking) while the 24-105 is best at smaller apertures. They are tools meant to be used differently, this exercise will give him quite different looks