Is 40mm a 50mm or 35mm lens?

[snaggs]

Heh, people must think Im a sh*t stirrer with the types of questions I have. Seriously though, if you have a 40mm lens, do you feel like you have a 50mm, or do you feel like you have a 35mm?

Maybe someone with a 40mm & 35mm or 40mm could post two pictures from the same spot to give an idea of the view.

Daniel.

 

[back alley]

when i had a 40 it felt like a 40.
really.

there is a difference btwn the 3 focal lengths, a small difference but noticeable.

when i go from 35 to 50 there is always a slight ajustment phase as i get used to the change again.

joe

 

[Todd.Hanz]

According to Karen N. at http://www.photoethnography.com/equipment.html

The 35 summicron has a 63 deg. angle of view.
The 40 summicron has a 57 deg. angle of view.
the 50 summicron has a 46 deg. angle of view.

so you can see the 35 and 40 are closer to each other, but it has been my experience (like Joe) that the two are different enough!

 

[snaggs]

So if you had a 40mm, you'd still want a 35mm? or would a 28mm get you buy?

PS. Wasn't "soup is good food" the Dead Kennedy's?

 

[Todd.Hanz]

Snaggs,
I bought a 40mm for my M4-P to go along with the 28mm Ultron, seems to be a good combo. I probably wouldn't buy a 35 unless it was for the characteristics of the lens (ie. 4th version- pre asph. summicron for the bokeh, etc.). They are probably too close in angle of view for me and this combo.
Some people say that 40mm is closer to our natural field of view, don't know.

And yes, thanks for the catch, you are very observant......"Soup is good food" was the D.K.'s, probably listening to Black Flag when I typed it 😉.

Todd

 

[back alley]

when i had a 40 it was in a combo with a 28 and a 90.

it worked well, although i had a hard time with the 28, too wide for me.

hey todd, maybe you could give an ol' timer some hints on using a 28mm, i quite like your wide stuff.

joe

 

[RayPA]

And yes, thanks for the catch, you are very observant......"Soup is good food" was the D.K.'s, probably listening to Black Flag when I typed it 😉.

Todd

DK's and Black Flag. 😛 Very cool, Todd. 😀 Jello and Henry would be proud!

 

[Doug]

Most lenses' actual focal lengths vary a little from the nominal markings, as Huck listed in another thread. A recent Leica 35mm measured at 34mm, and I think it was the Rollei Sonnar 40mm that was 42mm. If you're comparing these last two, then they're further apart in angle of view than would be thought from the markings. Still hard to justify buying both simply on the basis of the difference in focal length... but when the Leica 35 is an f/1.4 and the 40mm Sonnar is an f/2.8, plus the difference in "look", there are other considerations!

 

[Huck Finn]

Rollei Sonnar 40mm was 42mm.

Good point, Doug. My guess is that the 40 Nokton is a little on the long side. I think that both of these lenses are pretty much right in the middle between a 35 and a 50. From what I've read the Leic Summicron-C is more of a true 40 & therefore leans a little toward being wide angle.

 

[Huck Finn]

Daniel, think of the differences between 35 & 50 in terms of how they are used. Because it is a wider angle of view, a 35 gives you the option of including more in your photo or getting in close to your subject. The 50, on the other hand, is often thought of as a short tele, or a short portrait lens, because it allows you to put a little more distance between you and your subject. You can achieve shallower depth of field with a 50, which is another of its characteristics that is useful in portraiture.

The 40 represents a compromise between the two. It has more depth of field than a 50 & is therefore easier to focus quickly because you don't have to be so precise. Depth of field will keep a lot of the picture in focus. Like a 35, it is a good lens for shooting people because it is wide enough for groups &/or you can include some of your subject's environment in the picture. Being a little longer than a 35, you don't have to get up quite so close & can shoot at a little more of a distance with the same effect - more like a 50 in this regard.

Because it is not as wide as a 35, it is not as useful in tight spaces indoors. You'll more quickly run out of room when you're backed into a corner. Like a 50, you can still use it infoors to great effect, but its just not as versatile as a 35 in these circumstances.

Because of these compromises, some people don't like it, feeling that they don't quite have the benefits of either. Because it is the perspective closest to what people see with 2 eyes, others like it because the perspective seems so natural. I like it.

By the way, I enjoy your questions & comments. 🙂

 

[Doug]

I like the 40 quite a lot. I use the 40mm M-Rokkor, 43mm Pentax-L, and 40mm Ultron SL. If you subscribe to the theory that the natural view of the eye is matched by a lens having a focal length equal to the diagonal of the film image frame... The diagonal of the 24x36mm frame is 43.3mm. But this is usually cropped somewhat in length for standard print sizes. No cropping needed for 4x6 or 8x12 of course, but those sizes may have resulted from the 35mm frame proportions.

A 6x8 print would crop the frame to 24x32mm, and that diagonal is exactly 40mm. Perhaps a more common crop, the 8x10 (and 16x20) print uses 24x30mm, with a diagonal of 38.4mm. 11x14 is really close too at a 24x30.5 crop.

So, depending on the print proportions, a normal lens for 35mm should be in the range 38 to 43mm... if you buy into the theory. And this may be why 50mm (which is often really 52-53mm) can seem a little long, and why the 35mm focal length is just starting to get into that "wide" look.

 

[Huck Finn]

Further thoughts on this subject. . . Single lens, fixed focal length cameras typically use a 38-40mm lens for many of the reasons that have been mentioned. And because these cameras were typically being sold to amateurs & the great depth of field at this focal length means that there won't be a lot of out-of-focus shots. This latter point was very important to camera companies in the days before autofocus.

When Leica introduced the CL, they wanted to expand this concept. They made it small & advertised it as a two-lens kit (40/90) that was ideal for travel. They saw the 40 as a compromise but versatile focal length that was wide enough for many shots but still allowed you to take pictures of individuals & still be able to shoot from a reasonable distance - although not so much as with a 50. The 90 came along to give you some reach. Rollei seemed to be after the same concept in offering their 40/80 combination. The roots of the 40 mm focal length are in this history - a compromise for situations when you only want to carry one or two lenses. Both cameras offer 50 mm frame lines so that they can be used with the lens that is typically a company's sharpest & optically best lens.

Minolta with its 3 lens combination (28/40/90), positioning the 40 as an alternative standard focal length to the 50 (no 50 mm frame lines), & Cosina, with its 1:1 finder, have both extended the concept of how the 40 mm focal length can be utilized.

 

[RML]

When I got my CL body I, of course, wanted the Rokkor-M 40 as well. Wider than a 50 but less than a 35, it makes for a different experience. I find it a useful lens, especially in combo with my CV 25/4 and J9 85/2. But, as I normally carry the CL with my Bessa R + J8 50/2, the 40 has become just another lens to carry. Nowadays, when travelling (and I prefer to travel light), the CL carries the 25, the R the J8, and the J9 sits in my bag or coat pocket.

 

[kiev4a]

I've always believed the 35mm lens on a 35mm camera is closer to "normal" than a 50mm. One of my favorite lenses od all time is the 45mm Nikkor GN because it's a little wider that the 50mm and so compact.
If I had a 40mm lens I think my next jump would be to somewhere around 24mm. It's not that much wider than a 28mm but IMO gives the shooter more flexibility.

 

[Huck Finn]

I've read that a long time ago they started to refer to wide angles as beginning at 35 because that's when lines (rays?) started to bend, i.e. show some barrel distortion. Although much of that is corrected for today, it did make lenses more challenging to build at these wider focal lengths & it took longer to perfect them. So, a 40 can be viewed as the widest normal lens, i.e. the longest you can go without worrying about barrel distortion.

 

[kiev4a]

Good point.

 

[Huck Finn]

Hey🙂

Well actually, a "normal lens" on 35mm is 43.27mm (ie the diagonal of the frame), so that 45 Nikon lens is the closest to normal of all the ones you mention.
In answer to the original question:

A 35mm is a 35mm, a 40mm is a 40mm, and a 50mm is a 50mm.

M

Pentax 43/1.9 LE - the ultimate normal lens! :angel:

 

[Doug]

Pentax 43/1.9 LE - the ultimate normal lens! :angel:

Wouldn't it be ironic if this lens turned out to be really 45mm focal length? 😀

FWIW, the framing with this lens is a tight fit to the Minolta CLE 40mm framelines, at least at shorter distance like 2m or so.

 

[Huck Finn]

Where did you find one, Doug?

According to pentax, it is exactly 43 mm & was built specifically to match the diagonal of the 35 mm frame.

 

[Doug]

Huck, I got it from a Canadian RFF member whom I've not seen here since the purchase around the end of 2003. I first used it for the monthly theme of 'Shadows."