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enter image description hereenter image description hereI'm new to interchangeable lenses, but I bought the Sony 55-210mm lens to go with my new A6000 based on good reviews. I have no problems with the quality of images with the kit lens. They are nice and sharp.

With the 55-210mm, images are sharp and crisp at 55mm, but when I zoom out to 210mm the image quality is very bad.

I'm talking bright sunlight and in the middle of the day with a tripod. If I focus on something that is "unclose" at 210mm, then the image quality seems fine.

But, if I am focusing on something much further a way, the image quality is unusable.

If I can illistrate, let's say straight objects should have sharp lines like this.


the objects in view are like this...

-===-------------

fuzzy, and distorted kind of like how I described it above.

I'm using manual mode - 6.3 - 1/4000.

At lower shutter speeds, for example 1/250, the result is the same.

Is it just because, I simply can't focus well on very distant objects with my current setup?

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  • \$\begingroup\$ Can you post an image with the issue? \$\endgroup\$
    – rfusca
    Apr 20, 2014 at 20:29
  • \$\begingroup\$ I tried. But I got an error and the page crashed. I will try again soon and see what I can do. \$\endgroup\$ Apr 20, 2014 at 20:31
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    \$\begingroup\$ As you're talking about shooting in bright sunlight in the middle of the day, I suspect refraction is going to be having a significant effect here. But upload a photo and we'll be able to help a lot more :-) \$\endgroup\$
    – Philip Kendall
    Apr 20, 2014 at 20:50
  • \$\begingroup\$ Depending on the size of the A6000's pixels, at f/6.3 diffraction may also be beginning to affect acutance. \$\endgroup\$
    – Michael C
    Apr 21, 2014 at 1:10
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    \$\begingroup\$ Without a example, this question is just pointless handwaving and guessing. \$\endgroup\$ Apr 21, 2014 at 13:16

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Heat haze is almost certainly what you're seeing (possibly in conjunction with the camera's noise reduction - what ISO are you using?). It can occur on cold days just as much as on hot days; it is caused by differences in air temperature, not absolute temperature, and it's especially common above asphalt or concrete masses heated by sunlight - as in your picture. Here's another example:

enter image description here

You write:

This same refraction does not exist, let's say, if you use a pair of binoculars with the same length you will see the edges sharp and crystal clear without any refraction.

"Let's say" doesn't sound like you've actually done that. Besides, it would not be comparable because those distortions are constantly moving, and our brain is pretty good at averaging out that kind of non-systematic distortion and giving us the perception of higher resolution than our eyes actually have.

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  • \$\begingroup\$ ISO 1000, 1/4000, f6.3 \$\endgroup\$ Apr 24, 2014 at 16:29
  • \$\begingroup\$ Thanks - so, how can I make these longer shots better? A faster, sharper telephoto lens? \$\endgroup\$ Apr 24, 2014 at 16:31
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    \$\begingroup\$ @user1060500: reducing ISO as much as possible might help a little, but will probably just make the artifacts more recognizable as atmospheric distortions rather than general blurriness. It's not an issue you can fix with better equipment or technique - this kind of thing is the reason why the most expensive optical equipment on earth is put on top of mountains or in space rather than where it's convenient. \$\endgroup\$ Apr 24, 2014 at 18:55
  • \$\begingroup\$ The only thing you can do against bad atmospheric conditions is to avoid them: don't shoot directly across roads or roofs heated by sunlight; shooting from a higher-up position might help, and shooting later in the day, near sunset, will definitely help. \$\endgroup\$ Apr 24, 2014 at 18:58
  • \$\begingroup\$ Interesting. I will try shooting around sunset just to see if I can get the desired outcome. Sunset, means less light. This means higher ISO, lower shutter - which introduce their own problems with graininess and motion.... :) \$\endgroup\$ Apr 24, 2014 at 21:32
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My question might be stupid but is this a .jpg picture from the camera or have you manipulated yourself a camera RAW file? From what I have read about the a6000 (a lot because I ordered one)is that its in-camera jpg processing is too heavy handed, sacrificing the resolution to an unacceptable degree.

If this picture is indeed a camera .jpg, you could easily take another series of shots in RAW format and see what happens. I hope your problem goes away. In that case you might want to tweak the settings for in-camera noise reduction and sharpening to get a more pleasing result for your JPEG shots.

Courage!

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