Am I imagining things?

[LowSpark420]

You see my collection of gear in my signature.

I just seem to always pull the 50 out now as I think the image quality it produces is much more crisp than my other two lenses.

I am really looking for a good quality $400 - $800 lens for medium range shooting - inside and out...

[JeffreyG]

The 50 is probably sharper from f/2.8 and up.

But does it matter? Have you compared comparable images in normal print sizes or are you looking at 1:1 views on screen?

[LowSpark420]

Various sizes and formats (blog, FaceBook, prints for framing). Don't get me wrong, my longer lens is fairly nice, but I am looking to get a really sharp, quality lens as my next addition. After that, I am going to be looking for a new body.

I just rented the Canon EF 17-40mm f/4L USM lens to give it a whirl.

[JeffreyG]

If you can see a difference in web sized images, you can probably fix them with some processing. Web sized images are super low resolution and the kind of sharpness that we are talking about when discussing lenses should not be visible.

Try increasing contrast and bumping the blacks a bit with the zooms and see if you can make them look similar. Also be sure to sharpen for the output size, though this should apply to all lenses.

[LowSpark420]

What do you mean when you say "Sharpen for the output size"?

I have basically been "winging it" with my PP on my DPP software that came with my camera.

[DStanic]

Check out one of the 70-200 L lenses, I put mine up against my prime lenses, it is that good!

[EmmaRose]

Id say replace your kitlens with the 17-40 you rented.

[JeffreyG]

What do you mean when you say "Sharpen for the output size"?

I have basically been "winging it" with my PP on my DPP software that came with my camera.

None of this has to do with your lens issue, but let's hit this off topic part.

Suppose you have a 12 MP camera. This would be 3000 pixels by 4000 pixels. If you normally sharpen the image and then view it online it might look soft (depending on the website software) because your screen will likely be displaying the image as something like 600x800 pixels (about a half megapixel).

So the best way to display images online is to resize the image to the intended output and then sharpen. Lemmie give you an example:

First some comments:
Here in this sample shot we see that lens performance simply doesn't matter at web sized images. This shot is actually soft when viewed at 100%. It's ISO 3200, it's scraping the barrel for shutter speed and I think it's even backfocused a little.

But the main difference is in how it looks when I resize to a web-image and then choose to sharpen or not. Display matters more than absolute system performance in a huge range of real world situations.

[LowSpark420]

Gotcha! Makes perfect sense...

[toxic]

Sharpening is probably what you're missing. Digital files need to be sharpened to counteract the AA filter, and resizing also decreases apparent sharpness. If you're only seeing this "crispness" at 100% view on the monitor, it's largely irrelevant.

To answer your lens question...a 17-55 IS is about $800 used. Sigma 30/1.4 is $400? Canon 35/2 is $300. Tamron 17-50/2.8 is around $300 used, I think, as is the Sigma 18-50/2.8 Macro.

[Dan C]

I just got the Sigma 1.4 and highly recommended it. Also, the best value for sharpness has to be the Tamron 17-50 f/2.8.

[neilwood32]

I have to say my Sigma 18-50 f2.8 is pretty damn sharp!

[golfecho]

. . . but I am looking to get a really sharp, quality lens as my next addition. After that, I am going to be looking for a new body.



If you have even the slightest possibility of a full frame when that upgrade comes along, I'd spend the extra money and make sure whatever new lens you consider will work on a full frame . . . in other words, avoid the EF-S option . . .

[LowSpark420]

I think my next camera body will be the 50D or 7D...

[Snydremark]

I just picked up the Tamron 17-50 f/2.8 DiII about 3 weeks ago and I'd say it easily rivals my 50 1.8II in sharpness. Runs about $600.

[DStanic]

If you have even the slightest possibility of a full frame when that upgrade comes along, I'd spend the extra money and make sure whatever new lens you consider will work on a full frame . . . in other words, avoid the EF-S option . . .

Or buy used so you can re-sell it without losing much...