> Note! The exposure portion of this simulator currently does NOT work with Internet Explorer!
Don't tell me what to do!
Exposure Simulator
61–70 of 83 posts
Re: Exposure Simulator
#62For 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.
From the website: If I ever find a good moving prop like a small fan, maybe I'll also re-shoot new previews to demonstrate how shutter speed affects moving objects. Now, I'm just not sure how would one simulate a running fan with a picture. While for a static image you can have separated foreground and background and then apply effects for simulation (I know iPhone HEIC images have this property), for moving images y…
Why simulate? Most modern cameras can be controlled through USB. Just actually take each one (except for ISO, which you can easily fake), encode the frames in a reasonable bitrate MP4, then have a lookup for the frame in the video. :D
Re: Exposure Simulator
#63Earlier quoted context omitted.
I guess it depends on what "large file" and "regular size SD card" mean to you. The best selling SD card on B&H is 128 GB. Let's consider that "regular size". Fujifilm's GFX100 II is a popular medium-format mirrorless camera. Its sensor is 102MP. So each 14-bit RAW image is about 170 MB. 102M pixels x 14 bits = 1.428B bits = ~178M bytes = ~170 MB So a 128 GB SD card can hold ~771 images that are 170 MB. That's a lot…
I think they meant that you can pad your regular SD card with random data and leave just enough space for a few photos.
ahh that makes a lot more sense!
Re: Exposure Simulator
#64> 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…
Agreed. In other words, ISO is not exposure. Exposure is purely about how much light arrives on the sensor - which is a combination of scene illumination, object reflectivity, relative aperture, and shutter speed. ISO only plays a part in controlling how bright the output image is.
Re: Exposure Simulator
#65That 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.
Video showcasing ISO noise behavior of a few different cameras: https://youtu.be/iiMfAmWbWSg?t=94s
Excellent presentation and explanation. I agree with ~90% of it except the small part at 4m54s where he tries to give an answer about the existence of noise. Yes, sensor readout noise and A/D quantization noise exist, but he forgot the big elephant in the room: photon shot noise ( https://en.wikipedia.org/wiki/Shot_noise ). Light is inherently quantum mechanical, and the lower the brightness of a scene, the more that the discrete nature of light shows up in captured images.
Lately I've been researching cameras for astronomy, especially for deep-sky objects (DSOs) like nebulae that require hours of exposure time. The marketing material for these cameras go into a lot of detail: quantum efficiency (the percent chance that a photon converts into an electron), dark noise at different temperatures (fractions of electrons per second), readout noise (usually around 1 electron), and well depth (usually around 10k electrons). Compared to general photography, the astro community much more motivated to explain and keep track of all the sources of noise. Random product example: https://www.zwoastro.com/product/asi585mc-mm-pro/
Re: Exposure Simulator
#66> 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…
> If you keep the exposure the same, then changing the ISO on a digital camera will NOT introduce any more noise So does this mean that changin the ISO directly on my camera, or in DarkTable/whatever at post-proc time is virtually the same?
If you have an ISO-invariant camera, then yes - the final image would look the same whether you shot at low ISO and raised it in post versus shooting at a high ISO and doing no further editing. You can try it yourself. Or you can read the numerous reviewers who have already done that in the past decade, such as DPReview.
Re: Exposure Simulator
#67Earlier quoted context omitted.
I guess it depends on what "large file" and "regular size SD card" mean to you. The best selling SD card on B&H is 128 GB. Let's consider that "regular size". Fujifilm's GFX100 II is a popular medium-format mirrorless camera. Its sensor is 102MP. So each 14-bit RAW image is about 170 MB. 102M pixels x 14 bits = 1.428B bits = ~178M bytes = ~170 MB So a 128 GB SD card can hold ~771 images that are 170 MB. That's a lot…
I think they meant that you can pad your regular SD card with random data and leave just enough space for a few photos.
Or even use a computer to custom-format the card with a hilariously small partition (e.g. 128 MB on a 128 GB card).
Re: Exposure Simulator
#68> 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…
> Image noise does NOT come from high ISO, it comes from low exposure [...] 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). Sounds like you're saying that setting higher ISO does cause noise, but as long as you don't go too high you won't really notice the difference?
No. What they're saying is ISO multiplies brightness, essentially exasperating differences. Roughly, ISO 200 is 2x gain and so on. So if you have one pixel with a brightness value of 1, and the pixel to the left has a brightness of 5, and an ISO of 500, then it becomes brightness 5 and 25 respectively. Oversimplification.
Re: Exposure Simulator
#69Earlier quoted context omitted.
From the website: If I ever find a good moving prop like a small fan, maybe I'll also re-shoot new previews to demonstrate how shutter speed affects moving objects. Now, I'm just not sure how would one simulate a running fan with a picture. While for a static image you can have separated foreground and background and then apply effects for simulation (I know iPhone HEIC images have this property), for moving images y…
Why simulate? Most modern cameras can be controlled through USB. Just actually take each one (except for ISO, which you can easily fake), encode the frames in a reasonable bitrate MP4, then have a lookup for the frame in the video. :D
This would require 18000 frames
Re: Exposure Simulator
#70Earlier quoted context omitted.
From the website: If I ever find a good moving prop like a small fan, maybe I'll also re-shoot new previews to demonstrate how shutter speed affects moving objects. Now, I'm just not sure how would one simulate a running fan with a picture. While for a static image you can have separated foreground and background and then apply effects for simulation (I know iPhone HEIC images have this property), for moving images y…
Why simulate? Most modern cameras can be controlled through USB. Just actually take each one (except for ISO, which you can easily fake), encode the frames in a reasonable bitrate MP4, then have a lookup for the frame in the video. :D
I don’t know if I follow. You mean to keep a fan moving, take pictures with all the different combinations (aperture and shutter speed). Then merge on an MP4 file that you can lookup somehow the setting combo with the frame?
Sounds… reasonable I guess! I guess it can be simpler than I imagined. The owner of the site just needs a fan :-)