Thoughts on the 50mm focal lenght

My understanding of the "normal", "standard", whatever lens was also from the standpoint of perspective as opposed to magnification.

(I'm about to have a small glass of Martell Cordon Bleu cognac myself, Roger.)

I've never actually used a 50mm lense, But I hear it's great because it's a really fast prime lense. Though, I'd like to see some example pictured taken with a 50mm at night, and portraits of people.

If all goes well, I may end up getting a Nikkor 50mm f/1.4.

58mm

I kind of like the look of a 58mm lens, probably because my first serious camera was an Exakta with a 58mm Biotar.

50mm seems just a little wide-ish to me, though in this modern age that's what I use on my canon rebels when I am not using zooms.

The speed is definitely where 50mms really score. YMMV but you can get along really nicely with just one of these lenses (maybe with a couple of tubes/closeup lenses), though a 40mm is good too as it's just that little bit wider-and my Pentax 40 is hardly bigger than a lens cap, which is handy.

Black Dog said:

The speed is definitely where 50mms really score.

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Or better still, a fast 35...

Roger Hicks said:

But the new 50/1.5 Sonnar may incline me more towards 50mm too. It's gorgeous for colour though I've not shot much mono with it yet (and I haven't processed her mono either -- I'm doing 10 rolls today and 10 more tomorrow).
Cheers,

Roger

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How come you get the tedious chores and Frances get the fun part of printing?

The standard focal length for a film format is usually based on measuring the corners diagonally, in the case of standard 35mm, this is 43.26mm and therefore a 43mm might be considered as `standard` in theory. A focal length of 40mm-55mm will give what many will perceive as a `normal` perspective.

Keith, you've hit the nail on the head, that's the bottom line.

I don't use 50s as often as I used to, but they are still amongst my favourites for low-light environmental portraiture:

http://www.bard-hill.co.uk/temp/Corinna_50mm_f1-2.jpg

Pentax 50mm f1.2, at f1.2, taken in a bar lit by dim fluorescent lights, TMax 3200 rated at 1600.

(Apologies for the not very good scan - did it in a hurry a while back in order to post the picture in reply to a question on Usenet and haven't got round to doing a better one yet.)


Peter

Keith Tapscott. said:

The standard focal length for a film format is usually based on measuring the corners diagonally, in the case of standard 35mm, this is 43.26mm and therefore a 43mm might be considered as `standard` in theory. A focal length of 40mm-55mm will give what many will perceive as a `normal` perspective.

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Dear Keith,

Yes, but only when viewed from 43mm. Enlargement size and viewing distance are of fundamental concern -- see my post 51.

As for printing, I taught Frances how, then she got better at it than I am...

Cheers,

Roger

Roger Hicks said:

Dear Keith,

Yes, but only when viewed from 43mm. Enlargement size and viewing distance are of fundamental concern.



Cheers,

Roger

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Blimey, does that mean that we should only view photographs taken with a FISH-EYE Lens, when under water? :confused:

Keith Tapscott. said:

Blimey, does that mean that we should only view photographs taken with a FISH-EYE Lens, when under water? :confused:

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Nah, that's just codswallop.

I've never found any sense in the notion that a 50 mm lens, or any lens for that matter, somehow more closely corresponds to our eye than another lens. Personally my angle of vision is close to 180 degrees horizontally (i.e. I can peripherally see things directly to my left and right simultaneously). This is wider than any lens except the odd fish-eye. But my visual area of sharp focus is vastly narrower, similar to a super-telephoto. If I want to closely observe the letters in one of these words on the screen, I must move my eye slightly for each letter, such is the narrowness of my acute vision.

Then there is perspective. Perspective is not a property of any lens. The lens merely crops an area of the scene and records it on film; the perspective of that scene is determined by the subject to camera distance, and when viewing the print, the viewing distance and enlargement factor as outlined by Roger. However, I don't strive to manipulate the enlargement factor and viewing distance to "normalise" the perspective. In fact, I use a wide-angle lens precisely to allow me to shoot from closer, thereby stretching the perspective, which I make no attempt to "fix" in the print. In any case, with very wide lenses it's impractical to normalise the perspective at the print viewing stage because the print has to be so large and/or the viewing distance so short.

I very much enjoy shooting with a 50 mm lens. But I prefer the 35 mm. The latter offers excellent control of depth of field, from sharp everywhere to completely blurred backgrounds, in normal lighting conditions with normal film speeds. Wider than 35 mm and it's difficult to blur the background unless the lens is extraordinarily fast and the camera to subject distance is small. Longer than 35 mm and getting a large depth of field requires too much light or a tripod. I find the 35 mm just right.

Roger Hicks said:

Dear Keith,

Yes, but only when viewed from 43mm. Enlargement size and viewing distance are of fundamental concern -- see my post 51.

As for printing, I taught Frances how, then she got better at it than I am...

Cheers,

Roger

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Realistic perspective is obtained if the viewing distance is fn, where f is the focal length of the lens and n is the linear magnification of the negative (Adams book 3). For a contact print, n=1. As the near point is about 10", for realistic perspective the lens should therefore have a focal length greater than 10" (250 mm) and for comfort, allowing viewing at 12", greater than 300 mm. Therefore 5x7 format is too small for realistic perspective from a contact print even at standard focal lengths (210 mm) and 10x8 is barely OK for a gentle wide-angle (240 mm).

PS this post is more than a bit tongue-in-cheek!

And George ... amazing that nobody has pointed out that the dorphallic kinetic of the transvariated angular transit of the midpoint of both the human eyeball and the pupilian excrementus of the convexual threshold of any given processed transparent solid is .0069478.

In otherwords, what you consider 'normal' will always be determined by your personal Dorphilian Excremus, times your personal opinion.

Roger Hicks said:

Nah, that's just codswallop.

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A bit of a red herring really