Why most own 50mm lens?

[psychobiologist]

Would the angle of view be the same if I:

a. use 35mm
b. use 50mm, but take a few steps back such that the subject in focus appear the same size

the 35mm is good indoors, the 50mm for me indoors is a bit too close. i prefer the 50 outdoors though although i might like a 105mm+ better :X

min focus distance wise, the 35mm lets you get nearer and is wider, and thus can produce interesting compositions.


angle of view will be the same if you keep moving back of course, but the bokeh will be different, depth of field will be different for a 50mm at a given aperture and a distance, vs 35mm at a given aperture and a given distance.

 

[Deadpoet]

Having read the forum for quite a while, I'm puzzled why most choose 50mm as the "must-have focal length" lense in terms of general usage.

I understand that for 35mm film, 50mm's field of view and compression level is the closest to what the human eye sees. But with most cameras at crop factor of 1.5x~1.6x, a 50mm lens would essentially become a short portrait lens for 35mm equivalent of 75~80mm. I would have thought that a 35mm might have been a better choice.

Am I missing something here?

Why the question?

 

[LittleWolf]

I understand that for 35mm film, 50mm's field of view and compression level is the closest to what the human eye sees.

I just realised that I didn't refer to this part of the question. There may be technical and historical reasons for the the 50mm "standard lens", but it has nothing to do with the field of view of the human eye. For a 24mm x 36mm frame, a 50 mm lens gives a field of view of about 57 degrees (diagonal). The field of view of the (healthy) human eye is obviously much, much larger than that. Another way to visualize it is to use a 24 x 36 mm mask (e.g. a slide frame) and hold it 50mm away from your eye - you "crop" away a lot!

I'm not sure what you mean with "compression". I've seen the term applied in contexts such as "tele lenses compress the perspective, wide angles expand it", but this is wrong. Perspective is not affected by the focal length. From the same point of view, different focal lenghts merely "crop" the image to a different extent.

Correction: that should be 47 degrees, not 57 degrees.

 

[spazzer]

i use it because of its appeture

 

[Noakram]

Why the question?

Just curious, as I've read many ppl citing 50mm (for 35mm equivalent) as the focal length that is closest to what the human eyes see and hence recommend this as the standard lens. I'd think in this case, it would be the compression level (direct translate from Chinese 壓縮&#24863 or the perceived distance between subject and background instead of field of view, as explained by LittleWolf above.

But with many using DSLR and having to factor in crop factor. I still find that more people own the 50mm instead of the 35, 28 or 25 (depending on crop factor), hence the question.

What's your take then?

 

[Andy Ang]

Just curious, as I've read many ppl citing 50mm (for 35mm equivalent) as the focal length that is closest to what the human eyes see and hence recommend this as the standard lens. I'd think in this case, it would be the compression level (direct translate from Chinese ) or the perceived distance between subject and background instead of field of view, as explained by LittleWolf above.

But with many using DSLR and having to factor in crop factor. I still find that more people own the 50mm instead of the 35, 28 or 25 (depending on crop factor), hence the question.

What's your take then?

Most people own the 50mm prime instead of other primes is because 50mm is the cheapest.

 

[lsisaxon]

Just curious, as I've read many ppl citing 50mm (for 35mm equivalent) as the focal length that is closest to what the human eyes see and hence recommend this as the standard lens. I'd think in this case, it would be the compression level (direct translate from Chinese 壓縮&#24863 or the perceived distance between subject and background instead of field of view, as explained by LittleWolf above.

But with many using DSLR and having to factor in crop factor. I still find that more people own the 50mm instead of the 35, 28 or 25 (depending on crop factor), hence the question.

What's your take then?

Because suddenly, the 50mm becomes a cheap medium tele for portraiture. ;p

 

[Noakram]

Because suddenly, the 50mm becomes a cheap medium tele for portraiture. ;p

Looking at the majority of those that posted, it certainly seem like price is one of the important consideration.

 

[aloyyolaaloy]

its small and light too :sweatsm:

 

[Noakram]

its small and light too :sweatsm:

Right, agreed that being lightweight played a part as well. For me, it doesn't matter as I used to lugging my 2kg+ gear around.