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Author Topic: What am I doing wrong?  (Read 1752 times)

howard smith

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What am I doing wrong?
« on: March 13, 2005, 01:08:11 PM »

Is the 10D sensitive to IR?  I don't know.  But all an "IR filter" does is remove most of the visible light and allow red and infrared pass.  If the 10D does not record IR or very little compared to the red, there will be no IR effect.  Because the human eye cannot see IR, a true IR filter would look like you had left the lens cap on.  And the filter factor would be huge.

I used a "UV" filter that passed only UV.  I couldn't see throgh it and the filter factor was 10 stops.  The film I was using (T-Max) was relatively insensitive to UV.
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Lisa Nikodym

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What am I doing wrong?
« Reply #1 on: March 14, 2005, 07:03:40 PM »

Quote
when converted to B&W they look like regular B&W shots

What are you taking photos of?  Of some things, near-IR looks pretty similar to normal B&W, and that could be fooling you if you're not sure what to look for.  Vegetation and turbulent water should look very pale; blue skies should look very dark.  Things in the sun should look paler than things in the shade (relative to normal B&W).  Vegetation is the surest thing to photograph to see if it's working right; it should be very pale.

Lisa

Ben Rubinstein

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What am I doing wrong?
« Reply #2 on: March 13, 2005, 12:07:59 PM »

I have a cokin infra red filter which corresponds to a Wratten 89B. I'm trying to take IR pictures with my 10D but I'm not getting an IR effect to the photos, when converted to B&W they look like regular B&W shots. Added to that, the flare of this filter makes it all but useless. What am I doing wrong?

QuantumTiger

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What am I doing wrong?
« Reply #3 on: March 14, 2005, 07:21:56 AM »

There's a good thread on IR with the 10D here.

HTH.

howard smith

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What am I doing wrong?
« Reply #4 on: March 14, 2005, 09:22:24 PM »

The green foliage is the clue.  Red filter should show foliage as as very dark, but the IR effect is light.
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