petrochemist
TPF junkie!
- Joined
- Mar 9, 2014
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Most lenses focus IR in a significantly different place I can't see how IR focus assist can be reliable. Their focus assist may be barely in the IR, but with many lenses the difference at 700nm is already significant. IMO focusing at the wrong wavelength defeats the purpose of AF!DSLRs phase detect sensors are also under an IR block filter
I don't shoot IR, but I'm not sure I agree with this, as the viewfinder uses an AF IR assist light in low light. Having an IR filter on the focus sensor would negate it's use, would it not?