Water droplets or Dust in picture ?

bokke said:

Anyone able to help - see the attached picture. There are small "water droplet" markings on the picture (see top middle and also middle of beach)

They seem to be most noticeable at smaller apertures (f16 or higher)

I thought they may be dust - however I'd think dust would appear as black. Anyone have any thoughts / experiences to share.

Canon 5d mark ii

28-105mm canon lens

thanks

Patric

Click to expand...

Hmm.. tricky to say.

In my experience, sensor dust is dark spots. Oil spots on the sensor were a dark dot in a 'normal' circle with a dark outter circle/outline, like a bulls eye.
Do you have this issue in other shots?

I don't know about canon, but on a Nikon DSLR I can rotate the lens a few degree's as though removing it and still take a shot.

If you can do this, fix a piece of blank white paper to the wall, put the camera on a tripod and take a shot at f16 (1). Next rotate the lens a few degree's and take another shot (2).
Now move the tripod an inch or so left or right. Again take a shot of the white paper as was done in shot 1 (3). Now take another shot in this new position, with the lens rotated a few degrees as was done in shot 2 (4).

The reasons for doing this?

Shot (1) To see if the 'marks' are also visible in the white paper image.

Shot (2) If the 'marks' have moved, then its a lens issue, not sensor. If the marks are in an identical place, its a sensor issue.

Shots (3) and (4) This is to make sure the marks your seeing are down to the camera/lens and not what are on the paper. If the marks in shot 3 are different to those of shot 1 then your seeing marks on the paper not the in the camera/lens.

...Its easier to do than it sounds ;-)

--
www.hangitstraight.com

Weird. First, I'd recreate the effect by taking a picture of a clear sky. Then I'd check the rear optics to see if there are goobers on there. Then take a look at the sensor. If you still can't find anything, it might be the front element or cruddy filter (doubtful) or some sort of internal junk in your lens.

thanks for the suggestions - I'll try both and see what I can discover. I'll let you know.

Seems like an odd one eh ?

bokke said:

Anyone able to help - see the attached picture. There are small "water droplet" markings on the picture (see top middle and also middle of beach)



They seem to be most noticeable at smaller apertures (f16 or higher)

I thought they may be dust - however I'd think dust would appear as black. Anyone have any thoughts / experiences to share.

Canon 5d mark ii

28-105mm canon lens

thanks

Patrick

Click to expand...

These look like typical dust bunnies



The others look more like droplets than dust, one possibility is residue after a wet clean

Have you recently acquired the camera, was it bought new or has it had a previous owner.

SteveMi

Assuming you've not recently had your sensor wet-cleaned, my first thought is condensation.
Have you been taking the camera out from an AC room on a hot day? Or from a cold day into a warm room?

It may be from oil from the lens. A good wet clean should sort it out but I would look for the source of the trouble too. This thread on photo.net discusses the same problem.

bokke said:

I thought they may be dust - however I'd think dust would appear as black. Anyone have any thoughts / experiences to share.

Click to expand...

Have You Mount Your Lens on the Beach ?
Looks for me like Salt and Water on the Sensor.

Water + Salt is Corrosive, You should Clean the Sensor now.

I have had dust on a sensor enough times to say it does not look like what you have shown. There are two dust bunnies along the top edge of the photo maybe ⅕ of the way in from the left edge.

I have had oil on a sensor that came from the shutter curtain mechanism. It did not look like what you have shown. It looked had the same tonality as dust bunnies but was in larger blobs that were grouped close together and to one side of the frame.

The marks in your image are widespread and don't appear to be from a concentrated source close to the sensor like a shutter curtain. I'd guess the are from condensation or some water spray, but that is just a guess. I don't think that oil from a lens is the cause unless maybe you have a defectively assembled lens. Even if so, It just doesn't look like oil marks.

My guess is that it water from condensation or spray entering the cavity when the lens was off. Of course, that is a guess pure and simple. You might just want oread up on sensor cleaning.