Relation between dust and aperture setting

Started 8 months ago | Questions thread
soloryb
Senior MemberPosts: 1,279Gear list
Like?
Re: Relation between dust and aperture setting
In reply to Photonique, 8 months ago

What you are experiencing is exactly why Nikon recommends that you keep the aperture below f/16 for the D800. That dust is there - whether or not it is observable at the wider apertures. As far as I know, this dust becomes more visible due to the increased diffraction occurring at f/16 and above. Lower resolution sensors don't show this but a 36-MP sensor will.

You have two basic choices here. Either you can shoot at below f/16 or live with the dust and remove it in post.

BTW, one of the steps that I use before cleaning is to take several de-focused shots of a uniform light background (I use a mat board) with the aperture set to f/16. Vary the distance so that the images are not all exactly the same. Then import them into Lightroom and use 'Visualize Spots' under the Spot Removal tool. Playing with the slider will bring out even the most minute dust particles on the sensor. Even after careful wet cleaning, it's almost impossible to eliminate all the spots, but you can get the worst of them off if you're diligent enough. Any spots remaining probably won't be visible in normal shooting below f/16, but in your case, keep repeating the cleaning until any dust becomes tolerable.

soloryb

Photonique wrote:

Hi all,

this is my first post in this forum although I've been reading it since many years. I'm owning a D800 since 4 months now and I am very happy with it. However, I've had increasing issues with dust levels on my sensor. Anyway, my question is not related to how to remove such dust but I made an observation which I can't find an answer to:

When I take a photo of a bright white wall at high aperture number, say f22, I can clearly see a lot of dust particles. But when I set the aperture to f3.5, all dust particles are no longer visible. How can that be? I mean the dust will not change deepening on aperture setting. So it must have something to do with the light entering through the lens and hitting onto the particles. This phenomenon is also clearly visible when using life view mode.

Does anyone know why this is happening?

Thanks.

Photonique

 soloryb's gear list:soloryb's gear list
Fujifilm FinePix X100 Nikon D800E Nikon AF-S Nikkor 24-70mm f/2.8G ED Nikon AF-S Nikkor 70-200mm f/2.8G ED VR II Nikon AF Fisheye-Nikkor 16mm f/2.8D +9 more
Reply   Reply with quote   Complain
Post (hide subjects)Posted by
UGHNew
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow