BorisK1

Lives in United States MI, United States
Works as a Software engineer
Joined on May 7, 2004

Comments

Total: 408, showing: 1 – 20
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On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

Whoops, when your move the image closer, you're *enlarging* the apparent size, not reducing it.

Link | Posted on May 22, 2018 at 00:42 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

By moving a still image closer, you're reducing the *apparent size* of the subject, while *perspective* doesn't change.

What you perceive as "perspective distortion", is a mismatch between the subject's *apparent size* and *perspective*.

Try a simple experiment: Find a wide angle image with pronounced perspective distortion, and start leaning closer and closer to the screen.
You'll see that the image gradually starts to look less distorted. When you're very close to the screen, the distortion will disappear completely.

Link | Posted on May 22, 2018 at 00:36 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

> From the image? You mean a fixed image, as a print or an image viewed on the computer?

Yes, the viewing distance. If you're viewing the image on a screen, then the distance from, and the size of the screen.

> ANY distance, ANY size.
How you see an image, changes drastically with the viewing distance. It's not a matter of taste, but of geometry.

An image looks compressed (telephoto effect) when viewed at a wider angle of view than what was captured by the camera.
An image looks distorted (the wide angle perspective distortion) when viewed at a narrower angle of view than what was captured.

That's why I asked.

Link | Posted on May 21, 2018 at 23:10 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

Arastoo Vaziri:
"No, 35mm doesn't look natural at all."

At what distance from the image, and what image size?

Link | Posted on May 21, 2018 at 18:30 UTC
On article DPReview TV: Waterproof camera shootout 2018 (154 comments in total)
In reply to:

MikeFairbanks: I haven't read the article yet. But out of curiosity, do any offer manual modes of any type or at least shutter priority?

I'd love to use one for casual surfing photography when I'm out and see others get a good wave, but if I can't crank up that shutter then it's not worth it.

No article here, just a video.

Link | Posted on May 20, 2018 at 20:43 UTC
On article Panasonic Lumix DC-ZS200/TZ200 Review (539 comments in total)
In reply to:

sh10453: If I were a Panasonic decision maker, I'd stop this zoom race madness on this type of camera and concentrate on improvements.
- I'd fix the lens range at 24-300mm, but f/2.8
I'd then make this lens the standard lens on future iterations (ZS300, 400, 500, etc.) with continuous improvement until it's the sharpest lens in its class.
- Continue improving the "Cons" in the Conclusion section.
- 300mm in this type of camera should be sufficient.
- Kick Leica in the rear for lens variation, improve their QC, and stop them from getting their optics engineers drunk during work hours!

Just my 2 cents.

"- I'd fix the lens range at 24-300mm, but f/2.8"

The FZ2000 is f/4 at 300mm, weights two pounds, and has 67mm filter thread. A lens that's a full stop faster, will need to be wider (up to 67x1.44=96mm). That will be hard to fit even into FZ2000-sized body. A TZ200 is a third of the weight and a fifths of the volume.

Link | Posted on May 17, 2018 at 15:14 UTC
On article Panasonic Lumix DC-ZS200/TZ200 Review (539 comments in total)

The video crop is because of the stabilization and horizon leveling. It can be turned off on 1080p to shoot wide angle. From the specs on Panasonic.com, 35 mm equivalent focal length:

36 - 540mm in 35mm equiv. in 4K video recording
25 - 375mm in 35mm equiv. in 16:9 video recording / O.I.S. Off / Level Shot function Off
27 - 405mm in 35mm equiv. in 16:9 video recording / O.I.S. On / Level Shot function Off
30 - 450mm in 35mm equiv. in 16:9 video recording / O.I.S. On / Level Shot function On

Link | Posted on May 16, 2018 at 23:12 UTC as 38th comment
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

PowerG9atBlackForest: Contains a nonsense statement in one paragraph: "...For 35-mm motion-picture production, the 50-mm lens ... A 50-mm lens was an effective approximation of the focal length necessary to fill the diagonal dimensions of the 35-mm celluloid frame (43 mm) fully and consistently..."
The author is unaware of the fact that the format for "35-mm motion-picture production" is 18 x 24 mm with the diagonal dimension of 30 mm.
The author only put it right a few paragraphs later: "Just as it had for film, the 50-mm became a normal lens for photography because it was a reliable lens for completely and sharply filling the frame of a 35-mm photographic negative."

An image looks "normal" (no perspective distortion) when the viewer's field of view angle (FOV) is the same as the FOV angle of the lens that captured the image.

This means which lens is "normal", depends on the image size and the viewing distance.

In photography, traditional "normal" viewing is an 8x10 print at arms length (about 1 image diagonal, 13" from the eye) - that's FOV of 53°, matching the FOV of a 43mm lens on a 35mm camera.

50mm lens on 35mm has FOV of 47°, which matches an 8x10 held at 15".

In cinema, a "normal viewing distance" is considered about twice the diagonal of the screen, which is 28° FOV, so a "normal" cinema lens is longer (a 85mm lens on 35mm).

From Wiki, quoting Anton Wilson's book:

In cinematography, a focal length roughly equivalent to twice the diagonal of the image projected within the camera is considered normal, since movies are typically viewed from a distance of about twice the screen diagonal.
https://en.wikipedia.org/wiki/Normal_lens#Cinema

Link | Posted on May 16, 2018 at 18:16 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

> Shots taken at 35mm seem to record much better what I remembered/felt when I was standing at the scene. With a 50mm, the shot often looks pre-cropped.
That's because you're viewing it relatively close. Lean back from the screen a little, and the shot taken with 50mm will look more natural than the 35mm.

> Perhaps it's the way we individually perceive the world, or perhaps our eyes are not all exactly the same focal length?

Different people prefer to view images at different distances. If you like sitting 17 inches from a 21" screen, a 35mm equivalent shot will look "normal". If you prefer 24 inches distance, a 50mm equivalent shot will look normal.

On the other hand, people often *prefer* some distortion when viewing images, depending on the subject matter. "Natural" look isn't always preferred.

Link | Posted on May 16, 2018 at 16:10 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Gil Aegerter: Gosh I was surprised by this misstatement. But still an interesting piece from a history perspective, even if some technical aspects are incorrect.

"Due to digital cropping and the presence of a mirror on contemporary DSLRs, to get the same kind of perspective found on a 50-mm, the most “normal” lens for a DSLR is actually closer to 35 mm."

> "Due to digital cropping and the presence of a mirror on contemporary DSLRs, to get the same kind of perspective found on a 50-mm, the most “normal” lens for a DSLR is actually closer to 35 mm."

Reminds me of a kid who got the answer from the Internet, and is now trying to throw together some convincing-sounding words to fill up the box that says "show your work" ;-)

Link | Posted on May 16, 2018 at 15:38 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

BJL: Some massive ignorance in this article: it assumes repeatedly and wrongly that the 35mm motion picture format has the same 43mm diagonal as the 36x24mm still format, whereas in fact the motion picture standard is smaller: about 24x18mm in the early days, so with diagonal of 30mm, and now a bit smaller still: the same 24 to 25 mm wide but less high for the wider modern aspect ratios. So if Ozü indeed used 50mm most of the time in his movies, the field of view was distinctly narrower than with the 50mm on Cartier-Breson's Leica.

And of course perspective and proportions on the human face depend entirely on the distance from camera to face, not on the focal length.

BJL - yes, very much so.

> the displayed image of the subject looks as big when viewed "normally" as the original subject did when viewed by the photographer (with the naked eye, not through the viewfinder!)

The "scientific" term for "how big the image looks to the viewer" is "angular size", a.k.a. "apparent size".

Perspective distortion is a mismatch between the image's angular size and the camera's angular field of view. When they match, perspective distortion disappears, and the image looks "natural".

To make an UWA image look natural, press your nose to the screen ;-)

Link | Posted on May 16, 2018 at 15:29 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

shademaster:
> No. What "feels natural" depends on perspective and distortion
An image looks natural when there's no perspective distortion.

That happens when both the *perspective* and the *apparent size* match what a viewer would've seen from the camera's viewpoint.

> and has little to do with how the image (a projection) is viewed.
You set *perspective* by setting the camera-to-subject distance.
You set *apparent size* by setting the viewing distance (and the print size).

If you want to test this, find an image with pronounced wide-angle distortion, and start leaning towards the screen (decreasing the viewing distance). The closer you view it, the less distortion you'll see.

When the screen takes up as much of your field of vision as the lense's angular field of view, the distortion will go away completely, and the image will look "natural".

Sometimes, people *prefer* distortion. Which is why glamour photographers sometimes carry walkie-talkies to talk to their models.

Link | Posted on May 16, 2018 at 15:08 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

BJL: Some massive ignorance in this article: it assumes repeatedly and wrongly that the 35mm motion picture format has the same 43mm diagonal as the 36x24mm still format, whereas in fact the motion picture standard is smaller: about 24x18mm in the early days, so with diagonal of 30mm, and now a bit smaller still: the same 24 to 25 mm wide but less high for the wider modern aspect ratios. So if Ozü indeed used 50mm most of the time in his movies, the field of view was distinctly narrower than with the 50mm on Cartier-Breson's Leica.

And of course perspective and proportions on the human face depend entirely on the distance from camera to face, not on the focal length.

With motion pictures, what's traditionally considered "normal" viewing distance, is different from still photography. In photography, "normal" is an 8x10 at arm's length. In cinema, it's two screen diagonals away from the screen.

Which is why in photography, a normal lens is slightly longer than the sensor's diagonal, while in cinema, it's double the sensor's diagonal.

Unless you're in an iMax theater, and then all bets are off :)

Link | Posted on May 15, 2018 at 16:51 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

Mortal Lion: I find 35mm a more natural focal length of full frame. Not a lot of distortion yet a more comprehensive field of view.

What feels natural, really depends on how you view images (the size and distance to the print or the monitor).

Personally, I prefer closer viewing - so for me, wider angles feel more natural.

Link | Posted on May 15, 2018 at 16:26 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

PerL: A 50 mm lens is "normal" because on a SLR with 1x viewfinder the magnification is 1:1 at infinity . You dont get the impression of getting "closer" as you do with a tele, and you dont get the impression of getting ”away” as yo do with a wide-angle. That is why the term "normal" make perfectly sense.
This is offset somewhat by the fact that the viewfinder magnification is slightly less (0.8 x-0.97x or so on most SLRs (and a lot less on DSLRs). However, this is countered by the fact that a closer distances than infinity the magnification increases in the viewfinder. I just pulled out a Pentax ME, a Minolta SRT 101 and a Canon Ftb, all fitted with a 50 mm.
On the Canon which has the smallest viewfinder, objects appear life size at about 1 meter, on the Minolta a few meters further away and on the ME which has the largest OVF, a little more. With all of these it feels very natural to name the 50 "normal" since it gives a life-size view, or close to.
See also my comment further below.

I think the simplest definition is this:

A normal lens has the same field of view as you'd get by viewing the world through an 8x10 frame, held at arm's length.

Everything else follows, including the matching perspective, angle of view, apparent magnification, etc.

Link | Posted on May 15, 2018 at 16:14 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)
In reply to:

BorisK1: "a 50-mm best approximates human" *perspective*, not "sight". A picture taken with a 50mm lens (or equivalent, if not shooting 35mm) covers roughly the same area within your field of vision as an 8x10" sheet of paper, held at an outstretched hand. Or a smartphone screen at a reading distance. If a "normal" portrait is viewed at this distance, the nose-to-ears proportion is neither compressed (as in telephoto) nor stretched (as in wide angle).

Quite right. Perspective is determined by the distance to the subject.

What makes a normal lens "normal", is that it has the same angle of view as you'd get by viewing the world through an 8x10 frame at arm's length.

Which is why, when viewed at arm's length, an image captured by a normal lens duplicates both the perspective and the angular size of the subject, as seen from where the photographer was standing.

Link | Posted on May 15, 2018 at 13:53 UTC
On article How the 50mm lens became 'Normal' (62 comments in total)

"a 50-mm best approximates human" *perspective*, not "sight". A picture taken with a 50mm lens (or equivalent, if not shooting 35mm) covers roughly the same area within your field of vision as an 8x10" sheet of paper, held at an outstretched hand. Or a smartphone screen at a reading distance. If a "normal" portrait is viewed at this distance, the nose-to-ears proportion is neither compressed (as in telephoto) nor stretched (as in wide angle).

Link | Posted on May 14, 2018 at 15:16 UTC as 20th comment | 2 replies
On article Taking your drone to a wedding? Read this first (94 comments in total)

Do you, - BZZZ!!! - take this woman - BZZZZZZ!!! - wife?
- I BZZZZZ... CLONK!

Link | Posted on Apr 20, 2018 at 15:59 UTC as 21st comment
In reply to:

kodakrome: Outdoors there are no walls to bounce off of. Suppose I want to shoot a duck by bouncing the flash off a different duck. Can I do that?

Leono: Some compact cameras have limited controls. For example, if I wanted to shoot the moon with an Olympus TG-1, the only way to force the exposure time to stay above 1/100 was to enable the flash. Without the flash, the moon would be completely washed out.

Link | Posted on Feb 27, 2018 at 18:55 UTC
In reply to:

jhinkey: As long as it has 14stops of DR at base ISO and 40+MP then it will be great. Seems we'll be waiting a few years for that.

Placing a DAC into every pixel means DR is no longer limited by the capacity of the electron well, but by the bit count of the register that holds the result.

Link | Posted on Feb 18, 2018 at 03:30 UTC
Total: 408, showing: 1 – 20
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