Thursday, January 19, 2012

When will Digital Camera Manufacturers stop comparing lenses of various format to 135 (35mm defunt format cameras)?


Hi Photographer friends,

For years now, we have been buying lenses that are designed to a certain focal length, (say a 50mm lens) but when used on a digital camera, with a smaller sensor than the old 35mm film camera standard (24mm x 36mm), we are told that with a multiplying factor our new lens will have a different equivalent in 135 /35mm format. i.e. a 50mm lens attached to an APS-C digital camera with a sensor having a 1.5 multiplier will be equivalent to a 75mm lens.

A 50mm lens is always a 50mm lens in terms of focal length, and the perspective is always that of a 50mm lens no matter what camera it is attached to. I think it's time to drop the equivalency to the old 35mm film cameras and stop confusing entry-level photographers.

Assuming that you are already aware of the crop factor and 35mm format equivalency, and without going to a lot of explanation about it, (learn about the crop factor here  and here if you are not familiar with it or just Google it), the final true result is really the angle of view. 

During the film era, various format existed. There were the 35mm cameras, the medium formats (6 x 6, 6 x 4.5, view cameras in 4 x 5, 5 x 7, 8 x 10, etc.  Nobody ever used conversion factors to describe what a medium format lens would be equal to in 35mm cameras.

When the first Digital SLR cameras began to appear, manufacturer opted to use 35mm bodies and lenses, ( good economic decision but stupid photographic decision). The problem was that technology of the time only had developed sensors were much smaller than a 35mm film plane, hence the birth of the crop factor and equivalency to 35mm film cameras format.

Most young photographers don't know much about the old 35mm film cameras and they don't care. All   they know, or need to know,  is what a particular lens of a particular focal length  looks like when viewed through  their own digital camera viewfinder. That comes with minimal usage and experience. Once they know, they will be able to understand and pre-visualize what and when to use a particular lens on their camera.

It becomes even more ridiculous when describing a digital camera, having a sensor of the same size of the old 35mm film camera (24mm x 36mm), as a full frame camera. Hello! All camera are really full frame in their own format. Think about the Pentax 645D or the Leica s2. Should we call them super full frame or describe their lenses as a equivalent in 35mm format?

So I say... just continue making and sell lenses with their correct focal length stamped on but let the users figure out what they will be like on their particular cameras. It would be a short transition, but this equivalency is nuts. Lens are indeed labelled correctly, but described as equivalent to 35mm in magazines, camera manuals, advertisement, on the internet, etc. Please just stop the conversion factor. It all about what you see in your viewfinder.

When you look at an object, you likely can tell  its size fairly accurately. For example,  If you live in the U.S. you could visualize an object and recognize it as being about 1" inch long. You wouldn't have to know its metric equivalent, would you? The opposite is true if you live in a region that uses the metric system. Why using an equivalency with lenses and cameras?

Thanks for reading,

May the good lighting be with you,

Yvon Bourque

Post a Comment