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Why are modern 50mm lenses so damned complicated?

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Re: Why are modern 50mm lenses so damned complicated?

#281

Post by bostik »

PaulHoule wrote: post #225
bostik wrote: post #90

Earlier quoted context omitted.

Hah. I've had that experience but with sound. Long time ago, when dinosaurs roamed the Earth and AMD K8 was the pinnacle of technology, I invested in a basic home theater setup. A decent AV receiver, a subwoofer, two studio-quality monitor speakers. A friend warned me that the speakers I had picked were "crisp, but unforgiving". All of a sudden DVDs sounded wonderful. The audio tracks in TV programmes became clear. T…

In images they call that the difference between being "scene referred" vs "display referred". There is no generally accepted theory of stereo sound, instead there are at least three theories: (1) a method for mastering sound recordings intended to be played by two speakers that are right next to each other (two sides of a TV, see https://en.wikipedia.org/wiki/Sound_Retrieval_System for some theory) (2) mastering soun…

Thank you for that. I was only vaguely aware of (1) and in retrospect have had an intuition about (2).

I am delighted to be one of today's lucky 10000: https://xkcd.com/1053/

Re: Why are modern 50mm lenses so damned complicated?

#282

Post by antihero »

lmilcin wrote: post #3

I have a bunch of full frame lenses. Recently I looked at some very old ones I haven't used in a long time. I thought they are faulty (soft). After some diagnosing I found that it is not the fault of lenses but rather in the meantime I have started looking at images at 1:1 in Lightroom and gotten used to ridiculously sharp images from new cameras. Have you ever watched an old TV show and despaired how unwatchable it…

Depends on the lens really, a Super Takumar 50mm f/1.4 will happily compete in sharpness at f/8 (if I take well lit photos with mine it becomes the 24MP sensor that is the limiting factor in detail), but will indeed be significantly less performant at f/1.4. Even a decent Helios 44m will create gorgeous and impressively sharp images.

These lenses stopped down are better more for artistic photography as they have interesting bokeh patterns and lots of character.

Re: Why are modern 50mm lenses so damned complicated?

#283

Post by sudosysgen »

Zak wrote: post #244
sudosysgen wrote: post #226

Earlier quoted context omitted.

I disagree. The Panasonic 25mm f/1.7 is equivalent to a 50mm f3.4 on full frame. For 150g on full-frame you can get a 50mm 1.8 , at a cost of 150$ brand new. So on full frame at a similar weight and at the same price you get superior optics. If you really care about the weight, the 40mm 2.8 has the same weight and the same price but superior optics again. All modern FF cameras do distortion correction too. M4/3 lense…

Whether you should apply crop factor to aperture depends on whether you're interested depth of field, or exposure. You may or may not be able to adjust ISO to get comparable results at 50mm f/3.4 depending on which cameras you're comparing.

If you adjust ISO you will get more noise.

Noise is decided by the quality of the sensor, and the solid angle of light that hits each point on the sensor. The solid angle as it happens also decides depth of field.

So it is always true that you should apply crop factor to aperture. ISO is just not the correct factor to describe gain because an inverse crop factor is applied to it in effect.

So at the same exposure and shutter speed, at f/3.4 on FF you will get the same image with the same amount of noise as you would at f/1.7 on M4/3.

Re: Why are modern 50mm lenses so damned complicated?

#284

Post by schrijver »

hahamrfunnyguy wrote: post #172

I have the Canon 50mm/f1.8 aka the "Nifty Fifty". Got it a few years ago when it was still under $100. At the time, it was the cheapest prime lens you could but. I really like the photos I get with that lens.

That really is a great lens. Versatile as well since on a crop camera it’s a useful focal length too. IMHO the difference with the more expensive lenses is more about durability (a fair trade off since they’re cheap) and handling (easier manual focus, distance markings) than image quality.

Re: Why are modern 50mm lenses so damned complicated?

#285

Post by Zak »

sudosysgen wrote: post #283
Zak wrote: post #244

Earlier quoted context omitted.

Whether you should apply crop factor to aperture depends on whether you're interested depth of field, or exposure. You may or may not be able to adjust ISO to get comparable results at 50mm f/3.4 depending on which cameras you're comparing.

If you adjust ISO you will get more noise. Noise is decided by the quality of the sensor, and the solid angle of light that hits each point on the sensor. The solid angle as it happens also decides depth of field. So it is always true that you should apply crop factor to aperture. ISO is just not the correct factor to describe gain because an inverse crop factor is applied to it in effect. So at the same exposure and…

You'll have to set ISO higher to get the same image at f/3.4 as you would at f/1.7 on a smaller sensor because the intensity of the light is reduced.

I'm interested to learn more about the effect of light angle on noise. Do you have a source that talks about this? I didn't find anything useful in 2 minutes of searching the web.

Re: Why are modern 50mm lenses so damned complicated?

#286

Post by sudosysgen »

Zak wrote: post #285
sudosysgen wrote: post #283

Earlier quoted context omitted.

If you adjust ISO you will get more noise. Noise is decided by the quality of the sensor, and the solid angle of light that hits each point on the sensor. The solid angle as it happens also decides depth of field. So it is always true that you should apply crop factor to aperture. ISO is just not the correct factor to describe gain because an inverse crop factor is applied to it in effect. So at the same exposure and…

You'll have to set ISO higher to get the same image at f/3.4 as you would at f/1.7 on a smaller sensor because the intensity of the light is reduced. I'm interested to learn more about the effect of light angle on noise. Do you have a source that talks about this? I didn't find anything useful in 2 minutes of searching the web.

No, the intensity of light is not reduced. ISO is not gain. In other words, ISO 200 on full frame is the same as ISO 100 on M4/3 in terms of what actually happens inside the sensor. This is because of how the ISO standard is written.

As for light angle, it's a consequence of the second law of thermodynamics, that translates in optics as the conservation of étendue.

Basically what this means it that the amount of light captured from a light source is equivalent to the solid angle of light from that light source onto the entrance pupil - whose size is the focal length divided by the f number.

So basically, what determines in the same scene how much light is received by the sensor depends on the size of the aperture in milimiters.

So on a sensor of the same efficiency, it's the physical size of the aperture that determines how much light is captured.

Re: Why are modern 50mm lenses so damned complicated?

#287

Post by Zak »

sudosysgen wrote: post #286
Zak wrote: post #285

Earlier quoted context omitted.

You'll have to set ISO higher to get the same image at f/3.4 as you would at f/1.7 on a smaller sensor because the intensity of the light is reduced. I'm interested to learn more about the effect of light angle on noise. Do you have a source that talks about this? I didn't find anything useful in 2 minutes of searching the web.

No, the intensity of light is not reduced. ISO is not gain. In other words, ISO 200 on full frame is the same as ISO 100 on M4/3 in terms of what actually happens inside the sensor. This is because of how the ISO standard is written. As for light angle, it's a consequence of the second law of thermodynamics, that translates in optics as the conservation of étendue. Basically what this means it that the amount of ligh…

The intensity of the light is reduced because the aperture is the same diameter (50/3.4 = 25/1.7), but the light has to cover four times the area. To get the same exposure with double the f number and the same shutter speed will require four times the ISO.

> what determines in the same scene how much light is received by the sensor depends on the size of the aperture in milimiters

That's true, but the amount of light is not the intensity of light.

Re: Why are modern 50mm lenses so damned complicated?

#288

Post by astrange »

jeffbee wrote: post #207
astrange wrote: post #157

Earlier quoted context omitted.

Camera phones have significantly better processing than newer full frame cameras at this point; obviously they can't take the same pictures, but full frame cameras can't do HDR, noise stacking, night mode etc very well. You can do it by hand by shooting raws and editing them together but it's inconvenient. The autofocus is also more advanced in iPhones with lidar. I assume part of this is that the camera companies ar…

My Olympus does in-body HDR, noise reduction with stacking, low-light handheld with sensor stabilization, and more. It's not "full-frame" but full-frame is a meaningless condescension from the 35mm crowd.

Full frame sensors are quite useful indoors because you can shoot 50mm-e without having to be twice as far away.

For real pretension you have to get a Leica.

Re: Why are modern 50mm lenses so damned complicated?

#289

Post by astrange »

astrange wrote: post #288
jeffbee wrote: post #207

Earlier quoted context omitted.

My Olympus does in-body HDR, noise reduction with stacking, low-light handheld with sensor stabilization, and more. It's not "full-frame" but full-frame is a meaningless condescension from the 35mm crowd.

Full frame sensors are quite useful indoors because you can shoot 50mm-e without having to be twice as far away. For real pretension you have to get a Leica.

Besides that, the main problem with the processing in those cameras is they don't do it to RAW, only to 8-bit JPG, so nothing for HDR displays. iPhone can do fused RAW, 10-bit HEIC, and takes HDR photos and has an HDR display to show them.

It looks like they still don't really plan to add it: https://www.dpreview.com/interviews/9195902169/interview-son...

but at least if they had better bracketing options we could do it ourselves.

Re: Why are modern 50mm lenses so damned complicated?

#290

Post by sumtechguy »

ansible wrote: post #31
sumtechguy wrote: post #23

Earlier quoted context omitted.

What is more fun is the latency those effects add to images. Found that out the hard way playing some twitchy 'have to be just right' on the controls games. In my case it was almost 1/4-1/2 of a second. Even with all of the settings 'off' there is still a decent latency on the screen (down to about 70ms) which is just enough to mess me up on some games but not all.

I've been using a 46in 4K TV as a monitor, and the lag from the video processing felt super odd, until I switched the HDMI input to "game mode".

Mine still has the lag with 'game mode'. It is just a quirk of the thing I bought 10 years ago. It could also be like some of the other commenters are saying maybe the HDMI port I have it does not have the low latency bit but maybe 1 of the 4 does. Have to check again. It was not really a big deal as that is not really the use case for my TV. Which was watching movies :)
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