LIPH From Italy, joined May 2004, 848 posts, RR: 1 Posted (6 years 3 months 3 weeks 3 days 6 hours ago) and read 2035 times:
Looking into the viewfinder of my 30D I can see a little dust spot (shaped like a samll worm) in the lower right angle. Actually it is not a CMOS dust spot because it disappears changing the lens. I tried to look and clean (pretty quickly to be honest) the front and back side of my Canon 100-400 but it's still there. Any idea ? Thanks in advance.
Ranger703 From United Kingdom, joined Jun 2005, 157 posts, RR: 0 Reply 1, posted (6 years 3 months 3 weeks 3 days 6 hours ago) and read 2023 times:
More then likely to be some dust on the mirror if you are seeing it when you look through the viewfinder.I have something similar on my 20D,however it doesnt affect my pictures.
JeffM From United States of America, joined May 2005, 3266 posts, RR: 53 Reply 2, posted (6 years 3 months 3 weeks 3 days 5 hours ago) and read 2005 times:
Quoting LIPH (Thread starter): Actually it is not a CMOS dust spot because it disappears changing the lens.
Obviously. Nothing on your sensor shows up in your viewfinder. Think about it.......
These two comments contradict each other. If the spot is in the lens and you can see it in the viewfinder, then it's going to show up in pictures as well. To confirm this, try several shots of clear, blue sky at different aperatures.
But since you say it doesn't appear in pictures, the spot must be on the mirror. Of course, if the mirror is dirty you would see the spot regardless which lens you mount.
Time to do some testing to figure out which one it is.
B
LIPH From Italy, joined May 2004, 848 posts, RR: 1 Reply 8, posted (6 years 3 months 3 weeks 2 days 13 hours ago) and read 1886 times:
Quoting CalgaryBill (Reply 6): Time to do some testing to figure out which one it is.
Thanks guys...Actually will check better if it shows in pics. As far as I'm concerned it shouldn't (also because it's quiet large and it should be easily visible...), but will give an extra look.
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