Four Thirds Photography*

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About Four Thirds Photography*

More specifically for photos from the Olympus E-Series (E1, E300, E330, E500), but for the future, anything from the Four Thirds Standard.

*Whoever has used lenses designed for 35mm film with digital camera bodies incorporating sensors smaller than film knows the potential problem: a loss of wide-angle capability. Four Thirds solves this phenomenon. As the lens is always fully optimised to suit the sensor, you don’t have to contend with expensive wide-angle lenses that do not attain their intended specification – the angle of view you expect is the angle of view you get. The standard focal lens of the Four Thirds standard is around 25mm. So to compare for the 35mm format with a standard focal length of around 50mm, you have to use the factor 2 to have the angle of view compared (50mm = 100mm related to 35mm equivalent focal length).

Lens resolution & cornershading
Because the medium of film is very tolerant, there was no need to equip lenses with very high resolving power in the past. But with digital sensors, this has changed. Conventional lens systems simply do not deliver the lens resolution necessary for electronic sensors. They often have a resolution of only around 10 microns. However, because modern multi-megapixel cameras often have a pixel pitch of just 5 or 6 microns or less, overlapping and quality losses are the result. Therefore, the full theoretical performance of the sensor cannot be used. The problem is exacerbated with a greater number of pixels and a smaller sensor size.
All lenses designed for the Four Thirds standard ensure the image sensor is not wanting. The ultra-fine resolution attained through special manufacturing processes guarantees full sensor performance.

For edge to edge clarity
All Four Thirds-optimised lenses feature so-called near telecentric optics. Due to the nature of electronic sensor construction, image data is lost and there is a susceptibility to interference if light hits the pixels at a high angle of incidence. It causes a situation called cornershading, a loss in quality at the edge of the frame. This is especially associated with cameras using full-format sensors, where lenses must spread the light widely to reach each corner.
However, the near telecentric construction of lenses optimised for the Four Thirds standard ensures light hits the sensor at right-angles. This guarantees edge-to-edge colour, clarity and brightness.

General Advantages
All advantages of the Four Thirds System at one sight:
No decrease in image resolution due to insufficient lenses – full use of the sensor’s performance
No loss of wide angle capability
Significantly reduced occurrences of cornershading
Smaller, lighter lenses and bodies
Brighter lenses by approximately two f-stops with same depth of field as 35mm lenses (plus solutions to provide shallow depth of field if required)
Designed to remain compatible with future sensor developments
Cross-manufacturer interchangeability
Perfect harmonisation of lens and body due to communication standard
Secure investment due to future-oriented design