I have a Sony A7s ii that I purchased new from Best Buy. I only have only have one lens, a Sony Vario Tessar 16 - 35mm lens. Unfortunately in video and stills or photographs, there are these two faint dark spots that appear in the same spot. They are less noticeable in brighter lights but either way they're there and not wanted. The images are too large to upload here so I will provide links of pictures that I took:



I wondered if it was my lens, so I cleaned it, but that did nothing, they're still there. I am wondering if it is my sensor then. I believe the warranty I got from Best Buy mentioned a good cleaning of the body including the sensor, so I will double check with that and hopefully that will resolve the issue, but just in case, I want some other opinions from people probably far more experienced than me.


2 Answers 2


Those are almost certainly due to sensor "dirt".

Take two or more photos of a plain surface at small apertures - say f/22 - where sensor dirt is much more noticeable. For details see "CHECKING FOR SENSOR DUST" here

There is also a thin purple line running across most but not all of one photo. The source is not obvious but "it does not seem to belong". If you do not know the source of that line then doing so would be wise.

  • \$\begingroup\$ Thanks much. Here are some more pictures. As you can see, the thin line doesn't appear in every photograph. I can see it appear and disappear depending on where I'm pointing Unfortunately I do not know the source of that. cdn.discordapp.com/attachments/212455014273253377/… cdn.discordapp.com/attachments/212455014273253377/… cdn.discordapp.com/attachments/212455014273253377/… cdn.discordapp.com/attachments/212455014273253377/… \$\endgroup\$
    – SilverWolf
    Sep 18, 2016 at 9:01
  • \$\begingroup\$ You might want to clarify what you mean by doing so. \$\endgroup\$
    – Caleb
    Sep 19, 2016 at 13:08
  • \$\begingroup\$ @Caleb You might want to clarify what your comment relates to :-) - but, assuming it was my sensor contamination comment (which it may not have been) I have added a link to a much fuller snwer of mine relating to that subject. \$\endgroup\$ Sep 20, 2016 at 6:52
  • \$\begingroup\$ @RussellMcMahon Sorry if that was unclear. I just can't tell what you mean by If you do not know the source of that line then doing so would be wise.. Does doing so mean taking 2+ photos at small aperture, or bringing the camera back to Best Buy, or something else? \$\endgroup\$
    – Caleb
    Sep 20, 2016 at 12:02
  • \$\begingroup\$ @Caleb It meant "knowing" :-). ie If you do not know what the source of the line is then finding the answer and not just ignoring it would be wise". ie yes. Too obscure :-) \$\endgroup\$ Sep 21, 2016 at 2:29

First. You should try to find in camera options if it is possible to self clean sensor. Pentax cameras has shake reduction and it can be used for shaking dirt from sensor. Other cameras can have ultrasonic cleaner. I don't know if your camera has it so please check it.

Second. You can flip mirror and try to blow using rubber bulb blower or air spray. I personally suggest not to use air spray. Air spray can leave stains in some situations.

Third. I'd recommend to use special service. It is not expensive but professionals will take care of the most delicate part of the camera.

In most cases having dirty sensor is not a bad thing. If you shout photos with lot of details dust will not be visible, but if you shot a lot of smooth things like sky, and process a lot then dust can be serious problem.

It can always be fixed in postprocessing, but it takes time.


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