Why do I get blurry pictures at far distances, but sharp results up close?

Question

I took this picture:

https://www.flickr.com/photos/91552641@N06/15828810701/

and if you look at the details (like the trees on the right side) they are all kinds of muddy. I had the same experience when trying to take some group family photos (I had the camera on a tripod then, so I don't think it was due to vibrations).

However, this picture looks just fine.

And that seems to be pretty par for the course - I've tried different aperture values and zoom lengths, but it just seems like if I'm not focusing on something up close (less than 10' or so) then I just get a trashy image.

Is there anything I can do to fix/help this besides upgrading my equipment?

Answer 1

From the comments, it seems like this is your problem — you're probably focusing past infinity. See Why do some lenses focus past infinity?

Or, if you're not turning the ring all the way and instead relying on the marking, it may just be that the marking isn't precise enough.

Try the suggestions at Where to focus when shooting landscapes? instead.

Answer 2

I tried this experiment:

1. Stand in one place
2. Turn my iso as low as it will go (200)
3. Set my aperture as wide as possible (f/3.5)
4. Take a picture
5. Step my aperture one smaller, change shutter speed to compensate.
6. Repeat 5 and 6 until I hit the smalles aperture (f/22, in my case)
7. Turn my ISO to 11 as high as it will go (1600 in my case)
8. Work my way back down the f-stops
9. Turn my ISO to something in the middle and work my way back up.

What I learned:

• With a wide open aperture nothing was in focus
• Until about f/14 things were still really blurry
• At f/22 I had the amount of sharpness in the scene that I was looking for.
• As expected, higher ISOs had more noise - but there was no real change in sharpness at the different f-stops

I also looked around on Flickr at photographs made with my camera model. There were many scenes that looked quite nice. Of course they were shot with entirely different lenses. I think that's probably a great way to get an idea of what a camera is capable of in the right hands (and post production tools).