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Cameras and Lenses

ciechanow.ski

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Re: Cameras and Lenses

#51

Post by h_spacer »

The_Colonel wrote: post #35

I have a question for the more knowledgeable: Color filters on the sensor split the light into three wavelength ranges - red, green, blue. Then photosites measure intensity of light, which means that sensor only knows that the incoming photon is "roughly green", but doesn't actually recognize its precise wavelength. So e.g. when the light is pure orange, it falls down into red wavelength range and is counted as red.…

Filters allow rather large families of wavelengths through. You don't have just red, you have a fraction of green. Because your eyes only have three types of photoreceptors they can be fooled by playing back a similarly large family of wavelengths back.

Re: Cameras and Lenses

#52

Post by krisoft »

The_Colonel wrote: post #35

I have a question for the more knowledgeable: Color filters on the sensor split the light into three wavelength ranges - red, green, blue. Then photosites measure intensity of light, which means that sensor only knows that the incoming photon is "roughly green", but doesn't actually recognize its precise wavelength. So e.g. when the light is pure orange, it falls down into red wavelength range and is counted as red.…

It is because our eyes are also "incorrect". The cameras and processing and displays were engineered to match our eyes expectation. If some alien race with a sufficiently different physiology would look at our pictures they could tell that it is off. (and it wouldn't even mean that their eyes are more correct, just that their model is different.)

Re: Cameras and Lenses

#53

Post by barrenko »

ehejsbbejsk wrote: post #38

As a hobby photographer, this is simply amazing and the most intuitive article I’ve come across. This is a must read. I am curious, however, why we still can’t digitally reproduce bokeh. Apple is getting close. I thought LiDAR would theoretically solve that and could yield indistinguishable renders compared to analog lenses. That would be a game changer in my view and why I would like to see Apple develop a full-fram…

Not sure but - as film e.g. captures actual photons from the scene, probably some kind of information is encoded through that.

Bokeh is a kind of of space representation, similar to how you can basically "see" through hearing a sound stage of instruments separated properly when someone has a really good sound system, or how dogs have "5.1/7.1" sense of smell.

How does one encode that I have no idea.

Re: Cameras and Lenses

#54

Post by dbrgn »

lm28469 wrote: post #34

FYI there are digital sensors which aren't using bayer filters. Some are classic sensors missing the bayer filter (leica monochrome for example) other are based on different tech like Foveon sensors [0] Many people also debayer their cameras themselves, especially in astro photography [1] [0] https://en.wikipedia.org/wiki/Foveon_X3_sensor [1] https://stargazerslounge.com/topic/166334-debayering-a-dslrs...

That debayering sensor mod looks really interesting :) Nice way to quadruple the effective resolution of your camera, if you don't care about colors.

Re: Cameras and Lenses

#55

Post by dsego »

lm28469 wrote: post #34

FYI there are digital sensors which aren't using bayer filters. Some are classic sensors missing the bayer filter (leica monochrome for example) other are based on different tech like Foveon sensors [0] Many people also debayer their cameras themselves, especially in astro photography [1] [0] https://en.wikipedia.org/wiki/Foveon_X3_sensor [1] https://stargazerslounge.com/topic/166334-debayering-a-dslrs...

In Rawtherappee you can choose which demosaicing algorithm to use.

http://rawpedia.rawtherapee.com/Demosaicing

Re: Cameras and Lenses

#56

Post by smnscu »

h_spacer wrote: post #50
franga2000 wrote: post #24

Earlier quoted context omitted.

But it's way less effort than checking, isn't it? The name in the footer isn't English, so it's hard to know from that and there's no about page that I could find. The Twitter profile makes it more obvious, but I only clicked on it to check because of your comment. Why bother??

Slav surnames are gendered. * ski is male, * ska is female, * sko is neutral. Using gender neutral in this case is as insulting as calling him a dog. Other cases where using gender neutral pronouns insults everyone speaking the language is using Latinx for Latino. If you want to butcher every other languages genders like they are in English, use Latin instead - the gender neutral form of Latino in English since only…

I'm Romanian and have many Polish friends. This is not even remotely accurate, except for basket cases that I have yet to meet.

Re: Cameras and Lenses

#57

Post by emllnd »

barrenko wrote: post #53
ehejsbbejsk wrote: post #38

As a hobby photographer, this is simply amazing and the most intuitive article I’ve come across. This is a must read. I am curious, however, why we still can’t digitally reproduce bokeh. Apple is getting close. I thought LiDAR would theoretically solve that and could yield indistinguishable renders compared to analog lenses. That would be a game changer in my view and why I would like to see Apple develop a full-fram…

Not sure but - as film e.g. captures actual photons from the scene, probably some kind of information is encoded through that. Bokeh is a kind of of space representation, similar to how you can basically "see" through hearing a sound stage of instruments separated properly when someone has a really good sound system, or how dogs have "5.1/7.1" sense of smell. How does one encode that I have no idea.

Look into light field photography tech. It is possible to capture a ”volume of light”, within which bokeh & more can be adjusted after the fact. Issue is the amount of data generated and complexity of tech versus getting a ”good enough for most situations” image via simpler means (regular photo). Regular + depth images (Apple LiDAR etc) with help of AI can create something vaguely similar to actual bokeh, but they’re missing a lot of source data.

In the world of 3D rendering (content created from scratch) very advanced & realistic bokeh effects are possible, as an example see http://lentil.xyz for the Arnold renderer.

Re: Cameras and Lenses

#58

Post by h_spacer »

smnscu wrote: post #56
h_spacer wrote: post #50

Earlier quoted context omitted.

Slav surnames are gendered. * ski is male, * ska is female, * sko is neutral. Using gender neutral in this case is as insulting as calling him a dog. Other cases where using gender neutral pronouns insults everyone speaking the language is using Latinx for Latino. If you want to butcher every other languages genders like they are in English, use Latin instead - the gender neutral form of Latino in English since only…

I'm Romanian and have many Polish friends. This is not even remotely accurate, except for basket cases that I have yet to meet.

https://en.wikipedia.org/wiki/Slavic_name_suffixes

Hope that helps.

Re: Cameras and Lenses

#59

Post by bboozzoo »

smnscu wrote: post #56
h_spacer wrote: post #50

Earlier quoted context omitted.

Slav surnames are gendered. * ski is male, * ska is female, * sko is neutral. Using gender neutral in this case is as insulting as calling him a dog. Other cases where using gender neutral pronouns insults everyone speaking the language is using Latinx for Latino. If you want to butcher every other languages genders like they are in English, use Latin instead - the gender neutral form of Latino in English since only…

I'm Romanian and have many Polish friends. This is not even remotely accurate, except for basket cases that I have yet to meet.

Actually being Polish I can say it is correct, at least for the cases mentioned (also correct for suffix -cki). However it is true that there are surnames that do not follow this particular inflection scheme.

Keep in mind that Poles are likely to use a single, male variant of the surname, rather than explain the intricacies of inflection in the Polish language.

Re: Cameras and Lenses

#60

Post by lb1lf »

bboozzoo wrote: post #59
smnscu wrote: post #56

Earlier quoted context omitted.

I'm Romanian and have many Polish friends. This is not even remotely accurate, except for basket cases that I have yet to meet.

Actually being Polish I can say it is correct, at least for the cases mentioned (also correct for suffix -cki). However it is true that there are surnames that do not follow this particular inflection scheme. Keep in mind that Poles are likely to use a single, male variant of the surname, rather than explain the intricacies of inflection in the Polish language.

-A former girlfriend is of a Russian emigré family; she always got a chuckle out of Norwegians' inability to understand the concept of inflection.

Her father as a matter of course got letters from all her leisure activities, school &c addressed to 'Mr. Yuri ----skaia'. - as her last name was ----skaia, obviously his would be, too.

At least for us inflectionally challenged Norwegians.

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