Talk:Optical format

Doubtful Source on 16mm Conversion Factor

I may be reading this wrong, but expressing the optical format, for example, 1/3.2" or 1/1.6" by dividing the sensor diagonal in millimeters by 16 mm does not agree very closely with the dimensions given in the table here: Table of sensor sizes. Caltrop (talk) 20:49, 4 January 2011 (UTC)

I was about to add a comment myself when I saw this, but discovered yours. The claim actually only really applies to tube type camera pickups and in any case is only a rule of thumb not a definition as the image size is not a fixed parameter. A one quarter inch CCD sensor has a true optical format of exactly one quarter of an inch. Some formats are still named the old fasioned way. For example a "four thirds" format CCD sensor is actually just over 21 mm or about 0.83 inches - which may explain the confusion. The article requires clarification. DieSwartzPunkt (talk) 15:50, 6 January 2012 (UTC)

You are partly right and partly wrong. You are right that the optical format is not a hard and fast definition but an approximation. You are wrong in that solid state sensors are also measured in this rather peculiar way. If you remove your 1/4" CCD sensor from your camera, you are going to be bitterly disappointed to discover that it really does have a sensor size of around 4 mm. It is quite likely that this system has been adopted to make sensors sound larger than they really are. 109.153.242.10 (talk) 16:41, 6 January 2012 (UTC)

Article partially rewritten. It stated incorrectly that the optical format was the actual size of the sensor. It isn't, it is a hypothetical figure 50% larger. It also went on to describe camera tubes to which the term was never ascribed. 109.153.242.10 (talk) 12:32, 7 January 2012 (UTC)