Leica m8 Information Guide

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especially compact Leica M system in which the light arrives at the sensor’s edges at 
comparatively oblique angles. 
 
In completely new systems this parameter can be considered from the start, for example by an exit 
pupil with as great a distance to the sensor as possible.  
 
 
4.10 What is the difference between absorption and interference filters? 
 
Interference filters operate according to the principle of destructive elimination of light of certain 
wavelengths. In the case of the LEICA UV/IR filter, an interference filter, this has the advantage of 
allowing a precisely determined part of the light to be eliminated. Here, it is ultraviolet and infrared 
light. Such filters are mostly colourless – but they do call for greater thickness than absorption 
filters. The absorption filters fitted on sensors which usually suffice for an optimal colour rendition 
can be made much thinner. They operate by filtering out certain wavelengths with the help of  
applied colour dyes. 
 
 
4.11 Do the UV/IR filters interfere with other filters such as polarisers? 
 
Combinations of filters, i.e. polarisers and UV/IR filters can be used in conjunction without 
restrictions. The order in which the light travels through the filters is also irrelevant. 
 
 
4.12 Are there any seasonal effects that must be considered? 
 
In winter indoor shots under incandescent light are more common. Since these light sources have 
a stronger infrared proportion, the annoying effect of black colours reproduced in magenta can be 
expected more often. 
In spring and summer there are stronger IR reflections from the chlorophyll in green vegetation. 
This can lead to a yellowish rendition of plants during this season and therefore make it necessary 
to employ a UV/IR filter.  
 
 
4.13 Why doesn’t this effect appear with the LEICA Digital-Modul-R? 
 
Since the Digital-Modul-R is adapted to the Leica SLRs R9 and R8, only considerably less critical 
incident angles had to be considered when developing this system. SLRs generally have a longer 
back focal length (the distance between last lens element and the sensor surface) due to the mirror 
box. Therefore a filter with a thicker coating could be used in the LEICA Digital-Modul-R. This 
allowed the use of the interference technology, which filters out the IR light more effectively. 
 
 
4.14 Does this problem also affect me in B/W photography with the Leica M8? 
 
If you intend to do B/W photography with your Leica M8, the camera’s increased infrared 
sensitivity does not come into effect. Only synthetic black fabrics are rendered slightly brighter 
than they appear to the eye. This phenomenon was not considered to be important in any of the 
investigated cases.