Re: 4x5 field camera considerations - Reply

["Willem-Jan Markerink" <w.j.markerink@xxxxx>]

On 14 Dec 96 at 15:32, francisco sandoval wrote:

> What difference will it make if you take your picture to the higher
> F-stop that your lens allows you, so you will get higher details, is
> that correct or not, am I wrong??????   (I must be)... explain to me,
> excuse my ignorance........ :).......  Francisco

With 35mm camera's the golden rule is to close aperture 2-3 stops
from the highest opening (best performance of the lens), but for
large format you need much more to get an acceptable depth of field
(DOF). 
For infrared film you want to use this DOF to compensate/achieve the 
IR focus correction.
My German literature on the other hand also suggest *not* to stop 
down too far, since diffraction ('bending' of light around the 
aperture blades) is twice as bad with IR than with visible light, and 
diffraction is one of the 'errors' that increase with small 
apertures. 



--
Bye,

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      The desire to understand 
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<w.j.markerink@xxxxx>
[note: 'a-one' & 'en-el'!]

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Topic No. 3