Debating Canon 24-105mm f/4L IS vs. EF 24-70mm f/2.8L

[khan]

I read the FAQs and pinned threads, but didn't see this covered...

I'm pretty sure what my answer is already, but wanted to "ask the audience" to cement my decision...

First, the background:

I have a Canon XTI and have been shooting SLR for about a year. I have the kit 18-55 (non-IS), and I followed up with the 70-300mm 4.0-5.6 IS. I also picked up the 1.8 50mm prime.

I'm ready to replace the kit lens, and realize I'll lose 6mm on the wide end if it's not in my bag when replaced*. So with that, the two contenders enter the ring:

In the red corner, 24-105mm f/4L IS
In the blue corner, 24-70mm f/2.8L

Here's how I look at it. 24-105 is better as a walk around lens... I'll switch to my non-L 70-300 less frequently, and at 105mm especially, the IS will really help out. True, the 4 is slower than the 2.8, but then again, they say the IS gives you two stops of hand-holdability (I rarely "walk-around" with a tripod).

OTOH, you can't beat a fast lens in low-light conditions, right? Ceteris paribus (all else being equal, i.e. ignoring aperture's effect on DOF), you're capturing the same amount of light at 1/30s at f/2.8 as you are at 1/15s at f/4, so you need IS much less if it's a f/2.8 lens, right?

So it would seem that if IS gives you 1-2 stop headroom handheld, you might say that the f/4 IS is equivalent to a f/2.8 or f/2 lens, depending, so this would seem to throw the decision the IS way...

So in summary, where I'm at now, I'm thinking the 24-70mm f/2.8L is the way to go because it's a faster lens. While the IS is nice, it's also more critical from 70-105mm, the range that I already have covered with an IS lens (albeit not an L series). Sure, the IS can come in handy from 24-70mm as well, but so long as I'm willing to shoot wider open, having a lens that will go to f/2.8 will allow me a faster shutter speed-- a speed I can't shoot at (ceteris paribus) with the f/4, and where I'll have to depend on the f/4's IS to maintain sharpness...

Agree or disagree, I solicit your feedback (and if I do it right, you might be able to provide it via the poll feature-- first post, be gentle).

As far as "what are you shooting?", it varies quite a bit. Some action shots, some landscapes, some interior in low-light-no-flash, some detail work, some macro work, I'm really an all around hobbyist. Anyone interested in seeing some samples can check out my website or my flickr account.

-K

* I'm thinking I might next get the EF-S 10-22mm f/3.5-4.5 USM after this should I find that a cropped 24mm on my XTI is not wide enough. If I go full-frame in the future, I'll sell the XTI with the 10-22mm and the 18-55mm EF-S lenses...

[rediguana]

I really like my 24-70. It is a fantastic lens and produces wonderful images (in terms of quality). I'm using it on a crop sensor. Where the 24-105 is perhaps a more practical lens is the range that it would give you on a fullframe sensor. I also appreciate the extra stop for DOF, and the ability to shoot at higher shutter speeds to freeze action if you shoot at 2.8.

[Elmo]

The 24-70 will give you better image quality of the two. The key here is what are you plans beyond this lens an which will fit better into your desired set up.

Personally I find L (other than specality glass) glass overkill for cameras other than the 1D's. The reason is in most cases you can obtain lenses with great image quality and good build quality for a lot less money. The only real advantage to L's is the weather resistance and that is only utilized in the 1D's.

Have you considered something such as this 28-75 Tamron and you would have enough money left over for a 10-22.

And if you must have a RED RING try pen-striping tape.

[khan]

Originally Posted by Elmo

The 24-70 will give you better image quality of the two. The key here is what are you plans beyond this lens an which will fit better into your desired set up.

I'll probably eventually move to a full frame body in a couple years. When I do I'll probably be looking to fill the wide angle gap below 28mm. But yes, that's the lens I'm leaning toward as well.

Originally Posted by Elmo

Have you considered something such as this 28-75 Tamron and you would have enough money left over for a 10-22.

I looked at it early on, but not very closely, for two reasons. First, on a cropped sensor body, 28mm is equiv. to ~45mm-- 24mm is a bit better for wide shots. As you point out, I could afford the 10-22, so second, there's a smaller gap between the 10-22mm and the Canon's, although I admit 2mm-6mm is a very narrow gap.

Originally Posted by Elmo

And if you must have a RED RING try pen-striping tape.

Nice! Hadn't thought of that. But if I go with your suggestion, are there any stencils where I can paint the letters "Can" over the "Tamr"?

[khan]

Originally Posted by rediguana

I really like my 24-70. It is a fantastic lens and produces wonderful images (in terms of quality). I'm using it on a crop sensor. Where the 24-105 is perhaps a more practical lens is the range that it would give you on a fullframe sensor. I also appreciate the extra stop for DOF, and the ability to shoot at higher shutter speeds to freeze action if you shoot at 2.8.

Makes perfect sense, thanks.

[joefish]

I have a similar choice to make, except that I'm trying to decide between the 24-70 2.8 and the 16-35 2.8.

For me, F4 is not fast enough, as I shoot a lot of indoor event stuff. It sounds like you're already aware of it, but the more indoor stuff you do (or think you'll do) the more likely F2.8 would sway the decision for you.

I really like to be able to shoot wide (and want to replace my 18-55 kit lens too), and so the 16-35 would seem to be the obvious choice. But then, I'd also like to go full frame in the future (or at least it sounds good in theory), so in that case the 24-70 would probably be OK.'

Of course, the 24-70 is approx US$250 cheaper than the 16-35. And It would fit nicely with my 70-200.

Anyway, I digress. Back to your question: If you're happy with your 70-300 and it's quality (and speed) for now, then I would certainly go with the 24-70.

[errorz]

A little tid bit to add to the discussion:

From my research, I hear everyone complains about the size/weight of the 24-40 over the 24-105. I wouldn't mind handling the weight for a wedding or something, though for hiking/travelling it would probably become quite the nuisance...

Just stirring the pot a little...

[Farkled]

I, too, have the same choice to make, however my constraints are different. I seldom shoot below 35mm according to my EXIF data and I like to shoot long & tightly framed which is contrary to most of the world. In addition, being on the wrong side of the age curve, I find that I now have an occasional tremor in my hands. The tremor can be overcome with either shutter speed or IS.

According to SLRGEAR.COM the lenses are a tossup in terms of IQ. In my case, the extra reach is important but a primary consideration for buying the lens is shooting the grandkids indoors without flash if possible. Just to muddy the waters, I've used my daughter's 28-135 IS to very good effect - the $600 savings with this lens could be put to good effect by buying other gear.

[inkista]

I own the 24-105. As everybody's saying, f/4 just isn't fast enough for available light shooting, even with IS, especially with action photography of any kind. You're probably better off with the 24-70 f/2.8 if you're planning on a lot of available light shooting. If your main interest is architecture or landscapes, though, the IS works great.

The IS is more helpful with the 24-105 on the long end in easing the 1/focal_length rule, but there's a definite lower limit to what can be achieved. If I go pixel-peeping, I can't really go much lower than 1/20s. People will tell you they can shoot handheld cleanly at 1/6s or 1/2s with IS, and it's true--at web sizes, things will still be very usable. But I really doubt they're talking about pixel-peeping sharpness.

I love my 24-105, but it can be serious overkill at the price, as someone mentioned. A great deal of what it gets you can be netted through post-processing.

The other problem that some folks have encountered is in assuming that having a 10-22 and a 24-[mumble] lens will give you perfect coverage. And then they discover that 20-25mm is their most used range. Make sure that the breakover point is a convenient one for you to switch lenses at. I'd highly recommend analyzing the photos you have with the 18-55 with something like ExposurePlot to make sure you aren't shooting yourself in the foot by giving up the wide end, and that you can stand to have 22/24 as your breakover point.

[khan]

Originally Posted by inkista

I'd highly recommend analyzing the photos you have with the 18-55 with something like ExposurePlot to make sure you aren't shooting yourself in the foot by giving up the wide end, and that you can stand to have 22/24 as your breakover point.

What a brilliant idea! I never heard of that software before!

Except... I'm a die-hard Mac user, and long time Unix nerd.

Never fret, because there is a little command line Unix utility called "jhead", and using a little bit of command line magic, and the free utility "jhead" (which pulls EXIF data from JPEGs), I found that most of my pictures are taken at 300mm, followed by 70mm, 50mm, 55mm and 18mm. In other words, at the limits of my primary lenses...

For any other Mac users, here's the command to run to get your own mm report.

1. Launch Terminal.app
2. Type "cd [directoryname]" to get to your photos. Mine were in 'Pictures/iPhoto Library/Originals'
3. Run this command: "find [dirname] -name "*.JPG" -exec ~/Desktop/jhead {\} \; | grep Focal | sort | uniq -c | sort -n"

Here, [dirname] for me was "2007 2008", (listing the two years I've had my SLR), and my jhead app was located on my Desktop.

For those Mac users, here's where you can get jhead, a free EXIF command line utility:

http://www.sentex.net/~mwandel/jhead/

Anyway, what I found was that 98% of my shots fall outside of the 22-24mm focal length.

(And here's how I calculated that...

QuickSilver:~/Pictures/iPhoto Library/Originals] khan% find 2007 2008 -name "*.JPG" -exec ~/Desktop/jhead \{\} \; | grep Focal | sort | uniq -c | sort -k4 | sed 's/mm//' | awk '{print $5","$1}' > ~/mm.txt

I then opened "mm.txt" with Excel, and within moments had a chart of my exposures by focal length)

Anyway, thanks for the idea to examine my focal lengths. I'm afraid I have exposed my nerdy side.

(In case anyone cares, here is the chart at flickr)