Is this sharp?

Discussion in 'Beyond the Basics' started by ahelg, Mar 5, 2009.

  1. ahelg

    ahelg TPF Noob!

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    Ever since a friend of mine claimed my Pentax K200D tend to be a bit unsharp I've been very paranoid. I therefore thought I'd get someone else to take a look.

    The image I'm linking to is a jpeg at full resolution shot at ISO 400, 1/125 and f/6.7. Focal length was 80mm, which according to my program is the same as 120mm in 35mm terms.

    http://www.aleksanderhelgaker.com/IMGP1048.jpg
     
  2. NateWagner

    NateWagner TPF Noob!

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    well, first off, this is not a good photo to judge sharpness on. The reason there is there isn't really anything that particularly appears to be the focus (I'm having a hard time telling what is supposed to be in focus). and Also, the features I would usually look at to observe sharpness are pretty small.

    Truthfully, if you're looking to examine sharpness, choose an inanimate object of some sort, make sure it's on a tripod, test it at different focal lengths and apertures. etc.

    There are other problems, one is that most of the time, problems of sharpness that are related to equipment (much of it is usually due to operator error) are the result of the lens, and not so much the camera itself.

    Secondly, from what I've heard of the Pentax (and other pentax people feel free to correct me) is that it's jpeg processing isn't great in terms of sharpness, but if you use it with RAW it generally does an excellent job.
     
  3. Overread

    Overread has a hat around here somewhere Staff Member Supporting Member

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    IF you shoot RAW then the camera will not apply any sharpening to a shot (that is part of what RAW is) and thus you have to sharpen in editing (normally its the last bit of editing you do)

    Also sharpness is tricky to assess since its partly based on the output of the photo - if its a 500pixel web image the requirements for it to be sharp are different to if its a print on 8*10. This makes it a tricky subject to answer if a shot is or is not sharp - though the extremes of each are easy to define - the middle ground is very grey
     
  4. Chris of Arabia

    Chris of Arabia Herding cats since 1988... Supporting Member

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    It's sharp enough to tell you that the building behind has some serious structural issues going on - is the crowd there to collect enough money to repair it?

    I think the reason it's difficult to tell where the focal point is, is because a fairly small aperture has been selected. Only in the very foreground do you start to see that it's out of focus. Like Nate said though, to do a proper test, you'd need to set the camera and lens up on a tripod with a static subject, then make absolutely sure it's focused on the subject correctly. Oh and turn off any image stabilisation that may be present.
     
  5. Samanax

    Samanax TPF Noob!

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    That image has a lot of noise in it. Noise will degrade image quality and make your image appear soft. Image is slightly underexposed too, which adds to the amount of noise you're getting.
     
  6. AlexColeman

    AlexColeman TPF Noob!

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    Stop down to F8, go for a still life on tripod, with a singular point of focus.
     
  7. Early

    Early TPF Noob!

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    I'm thinking you were focused on the sign, and no, it's not sharp. It's better than I could do hand held, though.

    PS It's nice to see they have that much snow in the UK.:D
     
  8. Sw1tchFX

    Sw1tchFX TPF Noob!

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    I found the woman in the back of the sign with the purple scarf to be pretty sharp, your lens just isn't contrasty.


    seriously, don't be paranoid, it's wasted energy.
     

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