Changing lenses

[Cdeuce]

I have a nikon d90 and have 2 lenses (nikon 35mm and nikon 18-200) and I feel like my pics aren't as sharp as they could be. Am I better off getting the nikon 24-70 or a wide angle 12-24.

Thanks for the info or any other suggestions

[Jim Bryant]

Yes, most of those kit lenses that come with the cameras are not high quality and don't have the lower f-stops that one needs when shooting low light photography.

[inkista]

You're probably better off looking at your technique.

Check the following things off your list before looking at gear:

1. Do you know how to hold your camera properly?

2. Is your shutter speed fast enough?
Blur can be introduced by motion that's fast enough to be captured by the camera. The slower your shutter speed, the more blur you can see. There are two basic types of motion blur you have to be worried about: blur from moving the camera, and blur from a moving subject.

Camera shake blur typically occurs when your shutter speed is lower than you can handhold. The better your technique the slower you can go (hence point 1). Most folks have a threshold of about 1/30s (with an unstabilized lens), but longer lenses will require a faster shutter speed. The rule of thumb (depending on individual ability to handhold) is that your shutter speed should be at least (or faster) than 1/focal_length. So, with a 200mm lens, you need to be at 1/200s or faster to avoid camera shake blur. This is likely to be a problem with your 18-200 if you're zooming all the way in.

If you have to use a slower shutter speed, then use a tripod or other stabilization system. But it won't do a thing for subject motion blur.

With subject motion blur, it's a matter of how fast your subject is moving. When I shoot birds in flight, I routinely need to be in the 1/1000s territory, even though I'm using a 400mm lens.

3. Are you shooting wide open?
Shooting with your lens at its maximum aperture can be fun, but it can also introduce a host of issues. Lenses are very rarely at their best wide open. Vignetting, chromatic aberration, and softness are typical issues, particularly on wider angle lenses (<50mm). In addition, you'll be using the thinnest DoF the lens can render, which makes focusing critical. If you don't need to be wide open, if there's a little bit of headroom on the iso or the shutter speed, you may want to consider stopping down at least one stop to increase the performance of your lens. That 35/1.8? It's at its very sharpest around f/4. Learn not to have your lens wide open by default.

4. Do you have control of the autofocus?
Cameras are dumb. The autofocus system may have focused on something other than what you wanted it to. Are you sure the AF point you used was the one you wanted to use? Did you aim the AF point at something with high contrast (ideally where white meets black) and (ideally) in good light? What else in the picture IS in focus?

5. Do you know how to sharpen in post-processing?
There are a number of different techniques for sharpening in post, but nearly all of them can make a photograph seem sharper. When you're looking at sample images taken by people with more expensive gear, remember that someone who can afford a $2000 camera and a $1500 lens can probably also afford a full license for Photoshop and the lessons to learn how to use it. Sharpness is made both in camera and on the computer.

6. Are you sure you're not overly obsessed with sharpness?
Are you looking at your photos at 100% crop? Then nearly every lens will look inadequate. And are you sure you're not overlooking other important features in a lens?

That said. Yes, there are sharper lenses out there. But which lenses to get depends a lot on what you want to shoot and what budget you've got to spend, and why you don't like the lenses you've currently got for doing those things.

How to Take Sharp Digital Images

[inkista]

Originally Posted by Jim Bryant

Yes, most of those kit lenses that come with the cameras are not high quality and don't have the lower f-stops that one needs when shooting low light photography.

Jim, the OP says they have the 35/1.8. That is plenty of "lower f-stops that one needs when shooting low light photography".

[Jim Bryant]

Originally Posted by inkista

Jim, the OP says they have the 35/1.8. That is plenty of "lower f-stops that one needs when shooting low light photography".

I was talking about the 18-200.

[Cdeuce]

Thanks for the info, much appreciated. I'll be checking my settings on my next shots.

[Jim Poor]

Originally Posted by inkista

You're probably better off looking at your technique.

Amen!

You could also post some samples so that we can help you try to identify issues.

It's possible that you are doing everything right and need a new lens, but not really likely.

[douglas]

Originally Posted by Jim Bryant

Yes, most of those kit lenses that come with the cameras are not high quality and don't have the lower f-stops that one needs when shooting low light photography.

This may well be true, but as many amateurs only have kit lenses or "medium quality lenses" (whatever that may mean ), I think the post by Inkiststa makes the most important point for most of us amateurs.
For Pros its a whole different ball gamee

[milosh]

Originally Posted by inkista

You're probably better off looking at your technique.

I agree. I also have the 35mm f1.8 and I find it to be very sharp, much sharper than my 18-105.

Here's an example: http://image96.webshots.com/196/2/57...5yZZxwi_fs.jpg

[OsmosisStudios]

Originally Posted by Cdeuce

I have a nikon d90 and have 2 lenses (nikon 35mm and nikon 18-200) and I feel like my pics aren't as sharp as they could be. Am I better off getting the nikon 24-70 or a wide angle 12-24.

Thanks for the info or any other suggestions

"I have a toyota Yaris and I find i'm not getting the acceleration I would like. Should I go for a Lamborghini or a fighter plane"

Thats essentially what youve asked us.

The 18-200 is a superzoom lens designed for use on vacation or as a general walkaround lens. The 35mm (presumably the AF-S f/1.8 DX version) is an entry-level "standard" prime lens.

The 24-70 (f/2.8 AF-S N) is a pro-series FX f/2.8 zoom designed to exacting standards (and priced accordingly). The 12-24 (presumably the Nikon 12-24 f/4 AF-S DX) is, too, an almost pro-quality lens. It has a small zoom ratio (as with the 24-70) and a constant aperture (f/4). It is built to more exacting standards and attempts to do less at a time.

As a chef, would you want a swiss army knife (the 18-200) or a proper chef's knife (the 24-70)? The latter may not be as suitable for certain tasks, but it's much better at what it does. Same goes for the 12-24: it shares almost NOTHING in common with the 18-200 and much less with the 35/1.8.

Your question proves, at least to me, that you need to brush up on the basics of lenses before looking into anything further.