Where is the dust?

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InterrobangMP

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Where is the dust?

PostSun Nov 28, 2021 2:57 am

I have noticed what appears to be excessive dust when shooting in certain situations.
I've cleaned and swapped out multiple lenses, and found the same results, so I'm assuming it's on, or in the Metabones speedbooster, or the sensor. Both of which I have cleaned as well as I can, but the dust in the image seems excessive. I've noticed that BMPCC4k has a filter of some sort in front of the sensor. Could the dust be under the filter and on the sensor itself? On other cameras I've noticed dust spots when on the sensor directly, will be noticeable on a clear blue sky. But these only appear when shooting into the sun like this and only on the sun's rays:

Which leads me to believe that the dust is not on the sensor. Is there some way to figure out where the problem dust is?

I have tried multiple focal lengths and at each end of the focal range and still they appear, but I think they are vaguely more defined when focusing as close as the lens can go.
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Naveen Vasanth

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Re: Where is the dust?

PostSun Nov 28, 2021 4:08 am

Most likely the dust/corrosion of IR filter above the sensor..
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Frank Engel

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Re: Where is the dust?

PostMon Nov 29, 2021 7:18 pm

Are you using an appropriate filter when doing this?

https://www.bhphotovideo.com/explora/ph ... ph-the-sun

Note that (especially if you are shooting through a window) it is quite possible that the dust could be in the air rather than in the camera.
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InterrobangMP

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Re: Where is the dust?

PostMon Dec 06, 2021 6:52 pm

Naveen Vasanth wrote:Most likely the dust/corrosion of IR filter above the sensor..


Are you saying that this is under the filter? ie, i cannot get to it myself?
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Sean van Berlo

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Re: Where is the dust?

PostTue Dec 07, 2021 3:09 pm

Have you tried looking at your sensor glass? You'll be able to spot that stuff by eye.

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