The Photographic Film For Best Tips
The medium format films are identified by two acronyms: 120 and 220 mm Their characteristic is the height of the frame equal to 6cm. The main difference between the two codes is the length of the film: the 220 gives about twice as compared to 120 poses.
The film 120 has no hole of advance as in the case of 135, it does not have a containment structure (the film) but is simply wound on a plastic support together with a strip of black paper whose function is to protect from light . The format 220 is also devoid of the strip of protective paper, in order to reduce the dimensions of the film (in the end, the two dimensions are similar).
The film medium format allows, as reported in the table below, different dimensions of the poses, depending on the type of “stock” used (the structure that contains the film):
Size 4.5 × 6 format is a “rectangular” and allows you to get 15 shots from a film 120 or 30 220 http://smilesmultimedia.com. The size of a 6 × 6 is otherwise suitable for those square and a roller 120 can be derived 12 shots against 24 220. The size of 6 × 7 and 6 × 9 are best used as reproduce an asymmetry between the two dimensions, with the 6 × 9 identical, to report, to 135. The number of frames obtainable is approximately 9-10 exposures 18-20 and exposures from the roller 120 by the roller 220. Both rolls were introduced by Kodak in 1901 and 1965 respectively.
The difference between the various formats is directly linked to the amount of information “recorded” and on the emulsion. That translated into a language more suited to digital, the number of pixels. We could say that a 135 format (36 × 24) allows you to store about 30 million pixels, while a 6 × 6 up to 100 million: we can deduce that for large prints or “crop” extreme (perhaps with magnification) is the preferred medium format to 135.
Another film still on the market (although quite expensive and not so common) is the largest film format or even call sheet films. There are no needle but only sheets: each plate allows to obtain a single esposizione.Le dimensions are very generous: we find big slabs 10 x 12, 13 x 18 or even 20 x 25 cm Very “uncomfortable” to handle and use only in optical benches (from very generous size), these plates allow to obtain remarkable qualities, with the definitions too far (you get to gigapixel resolution). The equivalent of the optical bench, in digital, is often called digital back.