I have camera canon eos6D, and I have problem with ISO. When I`m shooting in daylight, or light indoor places, my camera always chooses to have auto ISO over 500, sometimes even over 1000. When I was shooting outdoors in the evening, ISO level was over 2000, even 5000. When I set it lower, not auto, pictures are very dark. Is there something wrong with my camera? Before 6D I had canon 1200D and there were no problems to shooth with low ISO (about 100) outdoors.

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    \$\begingroup\$ With what settings are you shooting? Maybe you have set a very short shutter speed or a closed aperture so your camera adjusts with the ISO \$\endgroup\$
    – timvrhn
    May 21, 2019 at 12:28
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    \$\begingroup\$ Sample pictures and image data, like ISO, aperture and shutterspeed please \$\endgroup\$ May 21, 2019 at 12:28
  • \$\begingroup\$ Just took pictures in my house. Shutter speed 1/400, f/4, tried ISO 400, 600, 800, 1000. Only with ISO 1000 I had normal picture.. \$\endgroup\$
    – Brenda24
    May 21, 2019 at 12:38
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    \$\begingroup\$ Indoors and evening are darker than you think. Our vision system is remarkably adaptive. \$\endgroup\$
    – mattdm
    May 21, 2019 at 13:02
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    \$\begingroup\$ Indoors, in daylight, a quick look at the display on my camera says it's going to be more like 1/5 or 1/4 second at f/4 ISO 100, so you were overestimating by a huge factor. I'd need ISO 3200 to reach 1/400s. \$\endgroup\$
    – Tetsujin
    May 21, 2019 at 13:43

1 Answer 1


ISO of a camera is related to sensitivity of light. In the case of digital cameras, ISO sensitivity is a measure of the camera's ability to capture light.

When you want to capture an image you need to always adjust your camera setting. Your camera setting should be a combination of ISO, shutter speed and aperture.

In a day time I would suggest you to put ISO around 100-250(fixed) and adjust your shutter speed and aperture according give a hit and try I am sure you will get good quality picture.

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    \$\begingroup\$ Thank you for your answer. I was shooting with aperture priority mode and my camera increased shutter speed up to 1/3000. Now I understand why I had this problem. Somehow my old camera did not do this. \$\endgroup\$
    – Brenda24
    May 21, 2019 at 12:45
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    \$\begingroup\$ In digital cameras, ISO is a measure of the analog amplification applied to the signal from the sensor before it is digitized. Any particular sensor can only have one sensitivity to light. \$\endgroup\$
    – Michael C
    May 21, 2019 at 15:50

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