T6i low ISO distortion issue

Discussion in 'Beginner Questions' started by Silas Apple, Sep 27, 2019.

  1. Silas Apple

    Silas Apple New Member

    Joined:
    Sep 27, 2019
    Messages:
    2
    Equipment:
    Canon t6i, Sigma 10-20mm F4-5.6 EX DC HSM, Tamron SP AF 90mm f/2.8 Di MACRO, Canon EF 50mm f/1.8 STM, Canon EF-S 18-135mm f/3.5-5.6 IS STM, Canon EF 75-300mm f/4-5.6 III
    Hey all, I'm having some issues with my Canon t6i. I know that this is a beginner camera, but its all I can afford at the moment.
    I expect distortion at high ISOs. I would assume anything above 2000 would have some visible distortion.

    But I'm seeing significant distorion at 200. This is incredibly frustrating as I feel like I'm missing out on some great shots. These are unedited and exported to 300DPI JPEG from RAW.

    Here is a shot I took this morning (I took a screenshot of it zoomed in to see the distortion).
    24mm @ iso 200, f/9.0, 1/80sec (Canon EFS 18-135mm)
    https://ibb.co/KjX9xTx
    zoomed:
    https://ibb.co/GMndgcQ

    This one I took a few weeks ago at 6400 ISO, but I feel like the distortion is similar:
    20mm f/13 iso3200 1/2000sec (Sigma 10-20mm)
    https://ibb.co/51wbZLZ
    Zoomed:
    https://ibb.co/QNJZsNp

    What can I do to fix this? Am I doomed to distorted pictures forever with this body?
     

  2. johnsey

    johnsey Site Moderator Staff Member Site Supporter

    Joined:
    Apr 21, 2017
    Messages:
    443
    Location:
    Fargo, ND
    Equipment:
    5dMk2, 20D, 70-200 2.8L IS, 100mm 2.8 Macro USM, 50mm 1.4, 85mm 1.8, 17-40mm 4.0L, Rokinon 14mm 2.8; Pixma Pro-100
    Well a few things to point out...

    If you zoom to 100% you will see the actual pixels that make up the image so don't peep that far, I can tell you zoomed in quite a bit. Viewing at the print size is appropriate, zooming in a step or two is fine, but you should be more concerned with how it looks when printed. If you print an image at 300dpi you can easily print an 8x12 if not closer to 12x18 inch image.

    Distortion is not the word your looking for, digital noise is the term, it is comparable to film grain, but digital out performs film now days this was not the case back in the early 2000's when dSLRs showed grain at 800 ISO printing an 8x10. We have come a long way since then.

    Your iso performance is as good as i expect. If you end up bumping the exposure up in post processing you will add digital noise, hence the idea that you should get it right in camera, even if raw is forgiving it has its limits. Your silhouette image would be very noising on shadows trying to bring up detail there if you did not intend the forefront to be dark. The fog is actually exposed quite well and that can be tricky, you will see a texture to the fog but you zoomed image is zoomed past what the printer will print unless you print it quit large at a low DPI.
     
    Last edited: Sep 27, 2019
  3. Silas Apple

    Silas Apple New Member

    Joined:
    Sep 27, 2019
    Messages:
    2
    Equipment:
    Canon t6i, Sigma 10-20mm F4-5.6 EX DC HSM, Tamron SP AF 90mm f/2.8 Di MACRO, Canon EF 50mm f/1.8 STM, Canon EF-S 18-135mm f/3.5-5.6 IS STM, Canon EF 75-300mm f/4-5.6 III
    Perfect that helps a lot. Thank you for the digital noise clarification. So when you say "As good as I expect," I'm assuming you mean that on a higher tier body the performance would increase? I appreciate the feedback- sometimes I'm my own worst critic I guess.
     

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