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Cameras and Lenses

ciechanow.ski

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Re: Cameras and Lenses

#161

Post by kepler1 »

echelon wrote: post #138
kepler1 wrote: post #129

Earlier quoted context omitted.

I'll share something with you. The level of consideration you have for people who are no more than 1% of the population is admirable. Very admirable, in comparison with the actual large problems that I'm sure you pay 0% attention to each day, and do make assumptions about. So very admirable that you go out of your way to bring this to the level of everyone having to select a pronoun in their dropdown menu because you…

You're lashing out in anger. Calm yourself. It seems like you dislike trans folk. I'm not sure what they did to hurt you, but I suspect your fears and hate are the result of conditioning. What harm is it to use singular "they"? It avoids assumptions. It also avoids sexism. Do you want a world where all contributions are assumed to come from men? You've got a lot of fear and anger. Reflect on it. Let it go. I don't kn…

I love how you go right ahead assuming, at the same time you preach against it. It's really respect worthy.

I'm not Christian. I'm not religious. I'm not Republican. I'm not disliking trans people. I'm not afraid of any such issues. All wrong. Yet you were happy to assume all that?

What I don't like is people who take on for themselves the cloak of righteous moral positioning on behalf of others, and force others to conform to their thinking because they believe they're right. Or worse, believe they're better.

"They" is not singular. You know the person is a man. You want to neuter everyone's speech to fit your worldview for the benefit of a 1%.

Strong opinions do not equal anger. And not everything in the world should be solved by just "can't we all get along and let people do what they feel is good". Opinions and attitudes such as you're showing are deserving of objection and being opinionated in the opposite direction.

Re: Cameras and Lenses

#162

Post by qwertox »

This article is stunning. The design, the way it presents the information, everything. I don't think I've ever seen such a good webpage.

Edit: Now I've seen some of his other pages... This man is a genius.

Re: Cameras and Lenses

#163

Post by antonfire »

heavenlyblue wrote: post #157
antonfire wrote: post #117

Earlier quoted context omitted.

That's for the second person pronoun, which are all gender neutral in Russian, whether they are singular or plural. (Like English.) We're talking here about third person pronouns, and the "the plural is the polite version and the singular is the casual version" doesn't extend to those. You wouldn't refer refer to someone in the third person as "они" rather than "он" to be polite.

> you wouldn’t refer you wouldn’t do that because Russia is a paradise for homophobia, not because it does not make sense. “Они” is a valid pronoun for the same thing than now means “them” in woke English.

The grammar of a language isn't about what "makes sense". A particular usage making sense or being reasonable isn't the same thing as that usage being part of a language.

If non-homophobic circles of Russian-speakers actually use "они" as a gender-neutral singular third-person pronoun, that's news to me. I wouldn't be terribly surprised to find out that's true. If it is, I would expect that to be a recent development, as in the last decade or so.

But it sounds like you're basing what you're saying on just mapping the English usage to Russian, or basing it on ground principles about what makes sense or doesn't, which is pretty unconvincing. Are you aware of examples of "они" being used this way in the wild by native speakers?

Anyway, whether it expresses politeness is a whole other can of worms, and I would be quite surprised to find out that on top of that in these circles "они" is used to express politeness in place of "он" or "она" (or I guess "оно") the way that "вы" is used to express politeness in place of "ты".

Re: Cameras and Lenses

#164

Post by ansgri »

perardi wrote: post #149
iamacyborg wrote: post #46

Earlier quoted context omitted.

Fuji also use what they call an X-Trans sensor. https://en.wikipedia.org/wiki/Fujifilm_X-Trans_sensor

Which is still pretty much a Bayer sensor, just with a different filter layout. You still have to demosaic to get a usable file. And a well-tuned RAW convertor to do so.

Well, it's still a CFA (color filter array), but definitely not Bayer, which is a specific class of arrangements.

Re: Cameras and Lenses

#165

Post by at_a_remove »

echelon wrote: post #79
kepler1 wrote: post #20

The site is the work of a guy, "him", and "his" work. We don't have to guess and say "them" and "their" work.

> The site is the work of a guy, "him", and "his" work. We don't have to guess and say "them" and "their" work. Assumptions are presumptuous and harmful. Everyone is a they/them until otherwise stated. These are extremely useful pronouns. You're a they/them. Calm down. You seem to be overly attached to regressive labels. I don't know what drives this in you, but the universe is burning and people just want to be happ…

>You're a they/them.

Why on Earth are you trying to dictate someone else's pronouns?

Re: Cameras and Lenses

#166

Post by ansgri »

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…

One of the limiting factors for modeling bokeh and flare-like effects is dynamic range limitation. You need extreme HDR capturing to accurately reproduce these effects, as they often play the largest part with bright, especially colored, light sources. I did work on flare simulation and while many effects can be modeled by a rather simple convolution (in the spectral space of course -- you cannot make a rainbow out of RGB straightforwardly), the problem is that kernels (PSFs, point spread functions) for these convolutions have very long tails and it's the shape of these tails that gives most of the 'natural' artistic feel.

The thing is, these tails become apparent only when you convolve with a very very bright source -- which on a typical 12-bit level linear raw image would amount to something like 10⁵-10⁶, i.e. needing 4-8 additional bits of HDR.

Here are some useful links on the topic of flare simulation, I believe bokeh has mahy similar aspects:

https://web.archive.org/web/20200119024053/http://simonwinde...

http://resources.mpi-inf.mpg.de/hdr/TemporalGlare/

Re: Cameras and Lenses

#167

Post by starky »

chandlerh wrote: post #113

Great article. One thing that's always stumped me as an amateur photographer is how an object is "in focus" when the rays from that object coverage to the smallest point, thus the smallest amount of pixels are getting hit. It would seem to me you would want to collect the max amount of information and thus use more of the sensor. How does converging to less of the sensor give you a sharper photo?

If you take up a larger part of the sensor, then the distance between any two details must be larger so the areas that their light covers over the sensor don't overlap. If they overlap, you have no clue where the information is coming from.

Look up circle of confusion, Rayleigh resolution criterion and sparrows resolution criterion for the technical details of resolution.

Re: Cameras and Lenses

#168

Post by matthiasv »

dingaling wrote: post #152

> Alternatively, we could increase the sensitivity of the sensor which is described using the ISO rating. Umm well, not really. The sensitivity of a digital CCD or CMOS sensor never changes; it has one 'native ISO' equivalent sensitivity and that's all. It creates the same output signal in response to a photon every time. Varying the pseudo-ISO simply varies the gain of the downstream post-readout amplifier. That's w…

> Sometimes it's better to take a deliberately underexposed photo and tweak regions of it in post to achieve the desired exposure instead of introducing global noise from in-camera amplification.

That is definitely not my experience for Canon's in low light situations. Here [1] is an example shot at ISO 100 but pushed by 5EV to match the brightness of the same scene shot at ISO 3200. The noise is much more tolerable for the latter.

[1] https://imgur.com/a/Ca9ccbK

P.S.: it's raw, no in-camera JPEG denoising in place.

Re: Cameras and Lenses

#169

Post by m463 »

this is quite a beautiful page, and in the first few seconds you can immediately grasp focus & depth-of-field/bokke. But then it keeps going!

Re: Cameras and Lenses

#170

Post by CamperBob2 »

The pinhole diameter slider is backwards; the objects should appear sharper as the aperture shrinks. Also it'd be good if you showed the effect of diminished light-gathering power at the same time, to emphasize the tradeoff.

All of the sliders should be labeled.

All in all, this is a good conceptual effort, but the details aren't strong.

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