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Exposure Simulator

115 pointsby sneelatoday at 11:16 AM53 commentsview on HN

Comments

semiquavertoday at 4:18 PM

I know that modern systems like aperture priority or full auto make things easier, but I maintain that the many photos I took with a fully manual film camera (Canon AE-1) were simply better than those taken with any subsequent DSLR. The simple act of calibrating the shutter speed, aperture size, and manual focus before and during shooting helps you slow down and think about composition and framing, making the end result more valuable. Same goes for the limited number of shots on a roll of film.

Nowadays it’s easier to just take lots of shots and fiddle with the setting and do bracketing and such. But I maintain something important was lost by the move to automatic cameras.

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PetitPrincetoday at 3:14 PM

For me it's missing something to illustrate the relationship between shutter speed and motion blur. If the subject was a running fan instead of of lightbulb that would have been ideal.

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Toutouxctoday at 8:41 PM

> image "noise" or "grain" that is introduced into a picture as you increase the ISO

Not this absolute shit again. This is not how photography works or how physics actually work. Image noise does NOT come from high ISO, it comes from low exposure (not enough light hitting the sensor). ISO is just a multiplier between a number of photons and the brigthness of a pixel in your photo. The implementation of the multiplier is (usually) half-analog and half-digital, but it's still just a multiplier. If you keep the exposure the same, then changing the ISO on a digital camera will NOT introduce any more noise (except for at the extremes of the range, where, for example, analog readout noise may play a role).

This "simulator" artificially adds noise based on the ISO value, as you can easily discover: Set your shutter to 1/500 and your aperture to F8, then switch between ISO 50 and ISO 1600 and look at the letters on the bulb. ISO 50, dark but perfectly readable. ISO 1600, garbled mess. Since the amount of light hitting the simulated sensor stays the same, you should be seeing slightly LESS noise at ISO 1600 (better signal to noise ratio than at low ISO), not more.

ChrisMarshallNYtoday at 11:58 AM

That does a fairly good job.

I'm sure that image nerds would poke holes in it, but it seems to work pretty much exactly the way it does IRL.

The noise at high ISO is where it can get specific. Some manufacturers make cameras that actually do really well, at high ISO, and high shutter speed. This seems to reproduce a consumer DSLR.

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agostoday at 6:04 PM

this is a cool idea, but not very well executed. it appears it just overlays white on top of anything? exposure does not work this way

1e1atoday at 12:22 PM

Changing the ISO appears to scale the noise differently from the rest of the image.

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trimastertoday at 2:26 PM

Not sure why value on the exposure compensation scale changes in manual mode when ISO is fixed. Shouldn't it be static in that case, unless ISO was in auto?

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pimlottctoday at 2:11 PM

It seems to be impossible to grab the sliders on mobile Safari

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moon2today at 5:59 PM

This is honestly the best and most simple way to learn photography, at least something basic that is still very hard to grasp sometimes. I know photography is not just about the photometer, and about depth of field, but this simple simulator helps to learn about these relationships between aperture size, shutter speed and ISO which always bugged me (sometimes my shots were bad and sometimes great).

erghjunktoday at 3:25 PM

that's an insane amount of noise at 200 ISO.

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ggambettatoday at 1:52 PM

Nice, but I'm going to need some ND filters :)

cratermoontoday at 2:54 PM

This is missing a setting for the kind of light falling on the subject. Is it full open sunlight? Open shade? Overcast? Sidelight? Backlight?

It all matters.