What is the most versatile fixed focal length for a prime lense?

Question

In other words, if you can only afford one prime lense, what focal length should you buy?

Answer 1

The "classic" is a 45-to-55 mm lens (that's a range - not a zoom lens) for a 35 mm film camera. If you bought that Sony Alpha (or most digital SLR's), there is a lens factor of 1.5 (1.6 for most Canon's) to consider. This would mean the equivalent "classic" normal lens would be a 30-to-37 mm lens. Sony has a 28 mm lens that would be the equivalent of a 42 mm lens. This is darn close to a "normal prime" lens. It's an f/2.8 lens. Working with the length is a good exercise in learning to see things for photography. It has approximately the same perspective as the human eye. All you have to do in your brain is put the frame lines in and you will "see" how the picture will look. If you want to zoom in - move closer. If you want to zoom out - back up.

Sony has a 50 mm f/1.4 lens that will really spoil you for low light situations. This might actually be your better choice with the Sony Alpha. It is a very mild telephoto, but that f/1.4 will allow you to stay in the lower ISO settings and perhaps you can avoid some of the trouble with digital noise that the Sony is known to have at higher ISO settings. With an f/1.4, you can shoot in the same light at ISO 200 instead of ISO 800 with the f/2.8. That's a huge difference.

The $100 price difference might seem huge, though. I hope not because I think this is really your better choice.

Answer 2

The focusing screen and film plane are at the identical distances from the lens ... that is how you are able to use the viewfinder to focus images ... I has to be that way. The only other method is the way rangefinder cameras work, because you are not looking through the lens, but a separate viewfinder with a rangefinder to help the photographer focus the subject. And just so you know there are three type lenses still used today. Prime lenses (50mm f/1.4 is a sample), Zoom lenses (12-24mm f/4.0 is a sample) and what is sometimes called "B" for bellows mounted or "M" for bellows mounted marco lenses (the Leitz 125mm f/2.5 is one example)

Answer 3

50mm. If you have a Canon or a Nikon both make a f/1.8 50mm lens that sells for around $100. They are fast and sharp. Basically great lenses for the money. On digitial SLRs with a crop factor the 50mm also make a very good portrait lens.

You could go with something longer but that would really limit your ability to use the lens as a good "walking around" lens. You could go wider but I wouldn't go smaller than 35mm.

I have one of those 50mm and love it.

Answer 4

Probably 55mm.

Most basic prime lenses are pretty standard on or around 55 mm.

Answer 5

It depends what you want to take photos. Normally it would be the 35mm which is good for a slight wide angle without distoration.