Is this filter dust?

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Clonetrooper

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Like a complete nobbler I took some shots at a football match on sunday. It was a bright sunny day and I forgot to remove the clear filter I use just for transit in my bag.

When editing I noticed these spots on the frame, never consistently in the same spot and not on every shot. First I thought my sensor must be dirty, but aren't they black spots, not bright?

I then looked at my 70-200 and noticed the filter was dusty, I did have a hood on but was shooting 45-90 degrees to the sun.

Am I right in thinking this is light from those flecks on the filter?

These are 100% crop I hope you can see what I mean :(

 
it certainly could be, but i would expect them to be more out of focus to be honest.... maybe dust on the rear element of the lens?

the easy test is if you take filter off, take a few snaps and if they are no longer visible then it's likely the problem.

give the rear element of your lens a couple of puffs with the rocket blower too.
 
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Gave it all another clean and did some tests on white and black backgrounds and can see nothing. As I say there was a far bit of dust on the clear protector because I never normally shoot with it on. It's just there in case the cap comes off in transit :)

There was the odd spec in the rear but nothing significant.
 
Dust on the filter is EXTREMELY unlikely to show on a photo. Check out this fairly extreme illustration: [click].

It's far more likely to be dust on your sensor. To check it, stop the lens down to something like f/16 or f/22 and take a shot of a blank wall. Don't worry if the shutter speed is slow because you don't care about the wall - the dust on your sensor will show at any speed and isn't affected by camera shake.
 
If they weren't in the same place each time, they could be out of focus bugs, plant matter etc...or miniature ghosts.
 
grotty said:
If they weren't in the same place each time, they could be out of focus bugs, plant matter etc...or miniature ghosts.
Click to expand...

Minature ghosts is the right answer. As StewartR said, unless you was using a tiny apeture, specks of dust on the filter won't really show up.
 
StewartR said:
Dust on the filter is EXTREMELY unlikely to show on a photo.
It's far more likely to be dust on your sensor. To check it, stop the lens down to something like f/16 or f/22 and take a shot of a blank wall. Don't worry if the shutter speed is slow because you don't care about the wall - the dust on your sensor will show at any speed and isn't affected by camera shake.
Click to expand...

I will try that tonight, will sensor dust show as light spots? I thought they showed as dark spots? On other pictures I took that day at a similar 2.8-4 but with a different lens I have nothing on the shots.
 
dannyjo22 said:
I will try that tonight, will sensor dust show as light spots? I thought they showed as dark spots? On other pictures I took that day at a similar 2.8-4 but with a different lens I have nothing on the shots.
Click to expand...
In my experience sensor dust is usually a dull blob of indeterminate colour which shows up well against light/white backgrounds. But at f/2.8 you won't see it - you have to stop down.
 
If it's not in the same place of each shot, not dark spots and not there anymore, my guess still is that is 'stuff' floating or flying about, illuminated/haloed by sunlight - as I can see the sun is out.
 
I just did a f22 test shot against a wall and I have a dirty sensor but it doesn't tie up to the places in the other pictures I took that where light spots. They are pretty random.

I need to get my sensor cleaned now as well, tbh I rarely go above f5.6 so have never noticed the sensor dirt before. :D

Looking through the shots again the worst ones are when I'm almost into the sun and it gets less and less until they are nothing with the sun behind me.

Anyone know anywhere near cambridge I can drop a camera in for a decent sensor clean?
 
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