perspective vs. field of view

[ferider]

This is a little philosophical, Joe:

I used to think preferred FOV was hard-wired in each of us. In the last year or so, after forcing myself to use something that I didn't use to like (35mm), I have concluded this is not so, it's simply a matter of acquired taste, being used to it, a trend (fashion?) in what we expect to see on flickr, etc.

If you look at historic, very successful cameras (for example the M3, or even the Canon P, which IMO, is a 50/100mm machine - its 35mm framelines are hard to use), 50 and tele back then was a very popular 2-lens, minimal kit. Having 35 as a go-to lens today, doesn't mean that people changed .....

By liking 35 on the RD1, you've simply "gone retro", switched to a 50mm perspective, and looking at your photos, done well with it I would think. That you have liked the 35mm lenses you are using, has helped of course.

Cheers,

Roland.

 

[FrankS]

It's magic! 🙂

 

[Finder]

first let me thank roland for addressing the main point of my original post.

and then apologize to all for i fear my question might have been phrased poorly.

i like 35 mm lenses, i assume it is the pov that i like.
when i use a 21mm lens on the rd1 to get close to that 35m pov it seems 'off' to me.
when i use a 35mm lens on the rd1 - which gives me a pov of a 50mm lens, i like it.
but normally i don't care for 50mm lenses in general.
so it seems to me to be that it's the 35mm lens that i like no matter which camera it is on.

i am trying to understand why this is?!

It maybe the distance you work at--pure speculation as there are no example photos. Do you stand further back with a 50mm on a 35mm compared to a 35mm on a 35mm camera/R-D1? Do you work at the same distances with the 35mm regardless of the camera? You may just like the closeness.

I am not sure there is an answer because you are now getting into a psychological response than a technical one.

 

[back alley]

It maybe the distance you work at--pure speculation as there are no example photos. Do you stand further back with a 50mm on a 35mm compared to a 35mm on a 35mm camera/R-D1? Do you work at the same distances with the 35mm regardless of the camera? You may just like the closeness.

I am not sure there is an answer because you are now getting into a psychological response than a technical one.

if i think about it...i change my distance when shooting now.
i like to be close when shooting normally.

my local buds who all shoot dslr with big zooms thing i'm a freak...as they shoot from across the street to my being a few feet away from a subject (people).

 

[back alley]

This is a little philosophical, Joe:

I used to think preferred FOV was hard-wired in each of us. In the last year or so, after forcing myself to use something that I didn't use to like (35mm), I have concluded this is not so, it's simply a matter of acquired taste, being used to it, a trend (fashion?) in what we expect to see on flickr, etc.

If you look at historic, very successful cameras (for example the M3, or even the Canon P, which IMO, is a 50/100mm machine - its 35mm framelines are hard to use), 50 and tele back then was a very popular 2-lens, minimal kit. Having 35 as a go-to lens today, doesn't mean that people changed .....

By liking 35 on the RD1, you've simply "gone retro", switched to a 50mm perspective, and looking at your photos, done well with it I would think. That you have liked the 35mm lenses you are using, has helped of course.

Cheers,

Roland.

occams razor suggests this is likely the case.

 

[kxl]

Keith, what part of the analogy of the tree and the windows is wrong?

Gregory

Greg - you weren't the other poster I was referring to.

 

[kxl]

This is a little philosophical, Joe:

I used to think preferred FOV was hard-wired in each of us. In the last year or so, after forcing myself to use something that I didn't use to like (35mm), I have concluded this is not so, it's simply a matter of acquired taste, being used to it, a trend (fashion?) in what we expect to see on flickr, etc.

If you look at historic, very successful cameras (for example the M3, or even the Canon P, which IMO, is a 50/100mm machine - its 35mm framelines are hard to use), 50 and tele back then was a very popular 2-lens, minimal kit. Having 35 as a go-to lens today, doesn't mean that people changed .....

By liking 35 on the RD1, you've simply "gone retro", switched to a 50mm perspective, and looking at your photos, done well with it I would think. That you have liked the 35mm lenses you are using, has helped of course.

Cheers,

Roland.

I ABSOLUTELY agree with this... regardless of the technical definitions of FOV and perspective and whatever you can prove or disprove mathematically, it is ultimately in the eye of the beholder.

I used to think that my preference was a ~50mm FOV, primarily because I enjoyed using my CV1/2 on my R-D1S. But having sold the R-D1S, I now like the 35,, FOV, using the CV 35/1.2 on a ZI. It wasn't really the FOV that mattered -- it was the lens!

 

[J J Kapsberger]

would i be correct in saying that a 35mm lens on a cropped sensor camera (say a 1.53 crop) would still have a 35mm perspective but a 53mm fov?

Here's how I read this: if I use a 35mm lens on a 1.53x crop camera, I'll achieve a 53mm FOV (which is correct), but will I achieve a new perspective or will the perspective remain the same?

What is 'perspective' in this case? I suspect it’s the perceived degree of foreshortening a particular FL imparts to a scene, relative to other FLs (all other things being equal).

If so, then perspective won't change, as the page linked to in Shadowfox's post illustrates.

A wide angle lens on a cropped sensor—eg, a 35mm lens on a cropped sensor achieving the equivalent FOV of a 50mm lens on a FF sensor—will still render a scene with greater apparent spatial depth than will the 50mm lens on the FF sensor. The 35mm FL’s inherent spatial rendering is not effected by a sensor crop.

Or am I wrong?

 

[kxl]

Or am I wrong?

Don't know what "spatial rendering" means.

One last point - put an SLR with a 24-70mm zoom lens on a tripod. Then shoot the same scene at 24mm, 28mm, 35mm, 50mm and 70mm.

Now crop the 24mm, 28, 35 and 50 to the same framing as the 70mm. Then resize the crop to the same size as 70mm image... While the resolutions will obviously be different, the images will BE IDENTICAL... Again, FL does NOT affect perspective, only subject distance does...

And before some brings it up, "zooming with your feet" is NOT the same as shooting with a zoom or a different focal length -- there IS a change in perspective, precisely because you have moved.

 

[Finder]

Now crop the 24mm, 28, 35 and 50 to the same framing as the 70mm. Then resize the crop to the same size as 70mm image... While the resolutions will obviously be different, the images will BE IDENTICAL... Again, FL does NOT affect perspective, only subject distance does...

And here is the problem with the argument. Perspective is not just a matter of the relative size of two objects in the image. Perspective is the apparent depth of the image. You need to take all those images and display them at the same size. You will see, as my example show, the 24mm lens having the greatest perspective and the 70mm the least.

To state clearly, to say that object distance for two random point is the only factor determining perspective is false. Changing focal length and cropping will change perspective. Perspective is not about the bits and pieces in the image. It is about the image as a whole. Look at the example. The building has rapidly converging sides, large foreground, and small roof. Classic strong perspective. Then look at the crop. The columns are nearly parallel, hardly any perspective in the image (they are leaning back, but they are leaning back equally).

Perhaps this will make you happier. Changing focal length and cropping changes what is foreground and background. So while you have not physically moved, the picture's foreground and background have changed position. So in the building shot, the grass is foreground and the roof is background. In the crop, part of the column is foreground and the brick wall is background. So the field of view of the lens or crop selects foreground and background and effectively changes the ratio of foreground/background distance.

 

[shadowfox]

first let me thank roland for addressing the main point of my original post.

and then apologize to all for i fear my question might have been phrased poorly.

i like 35 mm lenses, i assume it is the pov that i like.
when i use a 21mm lens on the rd1 to get close to that 35m pov it seems 'off' to me.
when i use a 35mm lens on the rd1 - which gives me a pov of a 50mm lens, i like it.
but normally i don't care for 50mm lenses in general.
so it seems to me to be that it's the 35mm lens that i like no matter which camera it is on.

i am trying to understand why this is?!

Let me say this, joe.

It makes sense that you'll like it because that lens still project the same image onto the sensor/film plane whether it's being mounted on RD-1 (crop-sensor) or Bessa R3M (full-frame).

You're merely pre-cropping those images to the physical size of the sensor.

I just realized this when I bought a 24mm Nikon AF for use on my Fuji S2, thinking that I'm getting a 36mm lens which is close enough to my *most* favorite focal length: 35mm.

However, the pictures did look "off" because the lens is still a 24mm lens. It differs in viewing-angle compared to 35mm by quite a margin, that's why.

 

[Chris101]

Folks will never get over the difference between lenses on a 24x36mm camera vs a 16x24mm camera. Yet everyone intrinsically understands the difference between lenses on a 6x6 medium format camera and a 35mm camera without any controversy.

Is this because "crop" digital cameras look like 35mm cameras and so they set up expectations?

 

[back alley]

Let me say this, joe.

It makes sense that you'll like it because that lens still project the same image onto the sensor/film plane whether it's being mounted on RD-1 (crop-sensor) or Bessa R3M (full-frame).

You're merely pre-cropping those images to the physical size of the sensor.

I just realized this when I bought a 24mm Nikon AF for use on my Fuji S2, thinking that I'm getting a 36mm lens which is close enough to my *most* favorite focal length: 35mm.

However, the pictures did look "off" because the lens is still a 24mm lens. It differs in viewing-angle compared to 35mm by quite a margin, that's why.

i agree with this line of thinking (and with others who have said similar)...but if this IS the case then why are folks so freaked out about the 'dreaded crop factor' ?

 

[back alley]

Folks will never get over the difference between lenses on a 24x36mm camera vs a 16x24mm camera. Yet everyone intrinsically understands the difference between lenses on a 6x6 medium format camera and a 35mm camera without any controversy.

Is this because "crop" digital cameras look like 35mm cameras and so they set up expectations?

ok, now you're gettin' all psychological on us...😉

 

[Chris101]

Unless one is talking about mathematical perspective (in which case only the subject distance, and not focal length/angle of view, matters) then the whole idea of perspective is a psychological topic.

 

[Roger Hicks]

Don't know what "spatial rendering" means.

One last point - put an SLR with a 24-70mm zoom lens on a tripod. Then shoot the same scene at 24mm, 28mm, 35mm, 50mm and 70mm.

Now crop the 24mm, 28, 35 and 50 to the same framing as the 70mm. Then resize the crop to the same size as 70mm image... While the resolutions will obviously be different, the images will BE IDENTICAL... Again, FL does NOT affect perspective, only subject distance does...

And before some brings it up, "zooming with your feet" is NOT the same as shooting with a zoom or a different focal length -- there IS a change in perspective, precisely because you have moved.

This is true only for similar size prints viewed at similar distances; ignores the fact that it is very unusual to shoot from a single viewpoint with lenses of a wide variety of focal lengths (you'd normally go closer with the wider lenses); and requires you to exclude some of the other clues to depth, e.g. texture. From http://www.rogerandfrances.com/subscription/ps perspective 1.html:

Perspective of texture

This can be viewed as merely another aspect of aerial perspective, but several leading authorities on perception apparently regard it as separate. The argument is simple: we can see more detail and texture in things that are closer to us. The better the textural rendition of close objects, therefore, the greater the impression of depth.

If on the other hand texture is obscured or 'smoothed out', this particular visual clue is lost. This is a major drawback, in our view, of the low-pass filters adopted by so many small-format digital cameras: in order to 'lose' unwanted Moire patterns created by everyday textured objects (such as woven fabrics) they simply throw away fine detail in skin textures, rock and many other natural subjects.

And Chris is right: perspective is a psychological topic. Why else would we cheerfuly accept linear perspective in the horizontal plane, but use shift lenses to 'correct' (= falsify) perspective in the vertical plane?

Cheers,

R.

 

[Andy Kibber]

No you don't.

Yeah, my comment was a joke. Those threads make me chuckle at first, then shake my head in disbelief.

 

[jonmanjiro]

Unless one is talking about mathematical perspective (in which case only the subject distance, and not focal length/angle of view, matters) then the whole idea of perspective is a psychological topic.

Exactly 🙂

In the Nikkor catalog available at camera stores in Japan, Nikon uses the mathematical "perspective". No psychological stuff at all.

 

[Finder]

Unless one is talking about mathematical perspective (in which case only the subject distance, and not focal length/angle of view, matters) then the whole idea of perspective is a psychological topic.

First, there is no "mathematical perspective."

Second, I have clearly shown the that focal length/angle of view does change perspective.

Third, perspective is an illusion of depth. How can you then separate the "psychological" component?

 

[Finder]

Yeah, my comment was a joke.

So was mine. But I still don't want to talk about DoF. 😉