24-70mm v 50mm

[herc182]

So I had a little spare time on my hands yesterday (understatement) and started taking some shots with my 24-70 (set at 50mm) and the 50mm.

First of all, the 50mm wide open (f1.8) is soft. We probably knew that. Doesnt really get sharp until around 2.8.

However, what surprised me was that the 50mm was sharper and had better contrast than the 24-70mm from 2.8 to f5.6. This was far from a proper
test, but SOOC, at 100% the 50mm beat the 24-70!

I also saw an article about primes versus an all rounder (the 24-70) and it was
a D700 with a 20mm, 35mm, 50mm and a 85mm I think.
They thought the primes were better optically. I thought the 24-70 would have probably won that contest too!

Admittedly you have the convenience of never taking the lens off and not
carrying around all the other primes, but for such an expensive zoom lens
I think I was surprised. I havent tested against other primes (dont own any
anymore!), so cant confirm that article.

Just an observation and wondering what you guys think.

Cheers

[RichNY]

The 14-24 will best the 20mm prime but then its primes all the way in terms of IQ.

[Prospero]

Even though the 24-70 is so expensive, I do not find it surprising that primes can beat it since primes are a lot less complex to design.

Having said that, personally I was never that impressed with the sharpness of the 50 f/1.8. I only use it wide open, though, so that's probably why. I have never felt that the 17-70 is lacking in sharpness (not on a 6mp camera, anyway), especially beyond 24mm, so I never put the 50 on my camera unless I need 1.8. Now that I have the 35, I hardly put the 50 on the camera at all, because the 35 is so much sharper wide open and the focal length is much more convenient for my purposes.

To compare only the sharpness will not give a complete view, obviously. Just compare focus speed, bokeh when stopped down (especially when comparing it with the 50 f/1.8), build quality, versatility and the wow-factor, and you'll see why you paid so much for the lens.

[r3g]

I always thought primes were supposed to be sharper than zooms at the same focal length and aperture.

[herc182]

Even though the 24-70 is so expensive, I do not find it surprising that primes can beat it since primes are a lot less complex to design.

Having said that, personally I was never that impressed with the sharpness of the 50 f/1.8. I only use it wide open, though, so that's probably why. I have never felt that the 17-70 is lacking in sharpness (not on a 6mp camera, anyway), especially beyond 24mm, so I never put the 50 on my camera unless I need 1.8. Now that I have the 35, I hardly put the 50 on the camera at all, because the 35 is so much sharper wide open and the focal length is much more convenient for my purposes.

To compare only the sharpness will not give a complete view, obviously. Just compare focus speed, bokeh when stopped down (especially when comparing it with the 50 f/1.8), build quality, versatility and the wow-factor, and you'll see why you paid so much for the lens.

You are spot on with the 50mm being soft wide open. I thought it was camera shake at one point...

And you are right regarding the rest of the criteria. The bokeh is beautiful on the 24-70 and focus speed lightning fast. It is heavy though which is why the 50mm on my camera is quite appealing!


I always thought primes were supposed to be sharper than zooms at the same focal length and aperture.

Yes they usually are, but I had heard differently for this lens. I am by no means a pixel peeper, and yesterday was the first time I actually bothered to check!

[VTEC_EATER]

You are spot on with the 50mm being soft wide open. I thought it was camera shake at one point...

And you are right regarding the rest of the criteria. The bokeh is beautiful on the 24-70 and focus speed lightning fast. It is heavy though which is why the 50mm on my camera is quite appealing!



Yes they usually are, but I had heard differently for this lens. I am by no means a pixel peeper, and yesterday was the first time I actually bothered to check!

Yeah, the 50/1.8 is really soft wide open. Too much coma at f/1/8. In fact its next to impossible to get a tack sharp image wide open. It gets much better however at f/2, and is deadly sharp at f/2.8.

I have found shooting at f/2 gives much more acceptable results and the depth of field difference is hardly field relevant.

Regarding the 24-70 I hear its great, has very sharp photos, is a wedding photographers dream, yada, yada, yada but it doesn't surprise me that a fast prime stopped down to f/2.8 beats it.

[K1W1]

This thread is a set up for Rooz to come in and rave about all his expensive fast primes isn't it. :-)

[TheObiJuan]

Hmmm, that's odd. I thought the 24-70 was supposed to be pretty darn sharp.
Months back I was talking gear with Joe McNally over here in Charleston and he pointed out that the lens was one of his favorites for its sharpness. He raved more about the 14-24, but the 24-70 still got plenty of time in our discussion.
I guess when I get one I'll test a couple out just in case there's sample variation.

[RichNY]

Hmmm, that's odd. I thought the 24-70 was supposed to be pretty darn sharp.
Months back I was talking gear with Joe McNally over here in Charleston and he pointed out that the lens was one of his favorites for its sharpness. He raved more about the 14-24, but the 24-70 still got plenty of time in our discussion.
I guess when I get one I'll test a couple out just in case there's sample variation.

The 24-70 is a great lens as zooms go and other than the 14-24 I don't know of any zoom that can match IQ with good primes. That said, I've yet to take a photo with the 24-70 and then think to myself how much better the image would have looked had I shot it with a prime.

[Turo]

I did a comparison back when I bought my 24-70 between it, the 50mm 1.8, and the 50mm 1.4D (not the G). On my D700, I found that at 2.8, the 1.4D was sharpest, closely followed by the 1.8, then the big zoom trailing both primes. At f/4 however, my copy of the 24-70 had a slight advantage over both primes, and by f/8 the zoom was significantly sharper.

I think I have all the test images in my computer still, if I find them I'll post them.

[Rooz]

i found the same as turo. by f4 the 24-70 had a slight edge but wide open it was a little behind. like rich said though, i cant recall a single shot i've taken with the 24-70 where i it was so signicantly down on IQ from a prime that i thought i blew the shot. the biggest benefit of the 24-70, apart from the zoom of course, is the AF speed is awesome. blitzes any nikon prime.

[Dread Pirate Roberts]

Months back I was talking gear with Joe McNally

Namedropper. I'm envious.:cool:

[herc182]

How do you take 100% crops? I took some test shots and wanted to post 100% crops of the two lenses. At the identical location.

Yes stupid question :)

[Prospero]

How do you take 100% crops? I took some test shots and wanted to post 100% crops of the two lenses. At the identical location.

Yes stupid question :)

If you want an identical location, it would be really hard to get identical crops using the crop tool.

I guess it's easiest to use the "change canvas size" option. Here you can fill in a new size in pixels, and it will crop the image until it has this size (unlike the "change image size tool" option where it would resize the image to fit the dimensions you specified).

Using default settings it will make a crop of the center. You can specify that it keeps one of the corners, or sides of the image. If you want another location you will have to use this tool in two steps, so that you first crop the image so that the area you are interested in is on the edge of the image and in a second step you crop of the rest.

It helps to record whatever steps you take in an action, so that you can later apply this action to the other images.

As always in photoshop, there are probably many other ways to do it, but this is the first method that came to my mind.
Did you use photoshop, by the way? I seem to remember you were using something else, but I'm sure that program will have similar options.

[Dread Pirate Roberts]

I must be missing something Herc so I'll answer the question literally.

Open the original image in photoshop or similar
set view to 100%
use the crop tool to select (crop) a bit of the visible image on screen
save as a new photo and post that?

[Prospero]

I must be missing something Herc so I'll answer the question literally.

Open the original image in photoshop or similar
set view to 100%
use the crop tool to select (crop) a bit of the visible image on screen
save as a new photo and post that?

The problem with that is that if you want to compare images made with two lenses side by side, odds are that the size of the crop and the location where the crop was taken from can differ (slightly).

This will make comparing a bit harder, and it just looks unprofessional :)

[herc182]

:) Fair enough. I dont have a tripod at the moment either, so there would be some real surgeon type precision to position the camera where it was after changing lenses :)

[Cyberwlf]

For me the 24-70 is second to none in terms of preservation of detail/sharpness. Pretty much the majority of day time pictures i've shot with my D300 on it ive been able to go straight to 100% view and it's sharp, the 50mm 1.8 certainly has never produced for me the level of detail/sharpness i'm now seeing with my 24-70. (Comparing both hand held mind you)

PS. I say daytime as the D300 requires me to jack up the ISO to noisy/lossy levels when it gets darker with the 24-70 to be able to make fair comparisons of the two (my 50mm f1.4 G does have the advantage over my 24-70 for lower light situations but it still is just a prime)

[Cyberwlf]

I did a comparison back when I bought my 24-70 between it, the 50mm 1.8, and the 50mm 1.4D (not the G). On my D700, I found that at 2.8, the 1.4D was sharpest, closely followed by the 1.8, then the big zoom trailing both primes. At f/4 however, my copy of the 24-70 had a slight advantage over both primes, and by f/8 the zoom was significantly sharper.

I think I have all the test images in my computer still, if I find them I'll post them.

It partially related to my evolving understanding of aperture but using the 50mm 1.4 (G) at first at 1.4 made me question if the lens was OK or not at first as most shots seemed so soft, now part of that ended up due to me not being used to the level of DoF a photo at f1.4 can have, but part of it also came back to that wide open it wasn't the sharpest. By comparison the 24-70 at 2.8, what is wide open for it, is definitely sharp.