Please help me with this mystery!

[rzFoto]

<span style="font-size: 12pt; font-family: 'Times New Roman'; mso-fareast-font-family: SimSun; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;"]


<span style="font-size: 12pt; font-family: 'Times New Roman'; mso-fareast-font-family: SimSun; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;"]I went out did some shooting last weekend, and most of the pictures had these random pixels either much brighter or much darker than the surrounding pixels. <span style="mso-spacerun: yes;"]All pictures were taken with my 40D and 70-200 f4 IS with ISO between 100-320.<span style="mso-spacerun: yes;"] The problem is clearly shown in the following example (original picture enlarged to 300% for better viewing). <span style="mso-spacerun: yes;"]Can anyone please tell me what this is?
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[MattG]

What quality were you shooting at?

[rzFoto]

I shoot RAW only. The image was cropped to 300% so people can see the dots easily. This problem only occurs with the 70-200 F4 IS lens.

[neuroanatomist]

This problem only occurs with the 70-200 F4 IS lens.

That seems to imply that the issue is with the lens...does it occur at all focal lengths/apertures? When you remove the lens and look through it, does the glass look clean?

[Daniel Browning]

My first guess is that it's an issue with the raw conversion. Can you post the raw file? Yousendit.com is a free way to host the raw file.

[rzFoto]

<span style="font-size: 6.5pt; color: #000000; font-family: Verdana;"]<o></o>

[rzFoto]

That seems to imply that the issue is with the lens...does it occur at all focal lengths/apertures? When you remove the lens and look through it, does the glass look clean?

<span style="font-size: 11pt; color: black; font-family: Verdana;"]I'd say it occurs in many focal length/apertures. The lens is very clean - the dots are clearly single pixels, so I am not sure if it is lens or the sensor or combination of both.

[Keith B]

That looks like images that use to come out of my old Nikon Coolpix 5000. That was a huge reason I bought Canon DSLR.

[rzFoto]

Keith, it is from a Canon 40D and the expensive 70-200 f/4L lens. Maybe Canon does not like me as much as you[:P]

[Keith B]

Keith, it is from a Canon 40D and the expensive 70-200 f/4L lens. Maybe Canon does not like me as much as you[img]/emoticons/emotion-4.gif[/img]

Yeah it is weird. I had a 40D and never experienced anything like that. I even used the 70-200 f/4 on it. Nothing like that.


Hope you or someone figures it out.