The kind folks over at Panvista Productions put together a great informational video aimed at helping us better understand ISO. Most of us already know that we can adjust exposure through ISO, but for many that’s about the extent of what we know about the subject. Panvista’s 9 1/2 minute long clip, however, goes far beyond the basics of ISO we learn in the beginning of our careers. The video gets right down to the nitty gritty as it shows us exactly what’s going on inside our DSLR or micro four thirds camera every time we adjust the ISO setting. This of course leads us into the topic of digital noise (ugh) and why it occurs (interesting). Overall, it’s a well rounded video that’s delivered in a way which is easy to understand and engaging.
Take a look at the clip, below, if not to learn about ISO and noise, then at least to admire the fun color graphs and bar charts the presenter whips up for us during the show.
[ via Reddit ]
wow, severely disappointed. spreading misinformation! noise does certainly NOT come from the wires in a camera. it is an inherent thermal property of the physical sensor semiconductor material (Johnson–Nyquist noise). lower noise can only happen if you cool the sensor (peltier cooler or liquid nitrogen, etc.). ISO is ‘gain,’ also know mathematically as the digital multiplier of the pixel values. noise is the random fluctuations of the sensor digitizing photons to electrons.
http://en.wikipedia.org/wiki/Film_speed
http://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise
http://en.wikipedia.org/wiki/Thermoelectric_cooling
I agree, there are many errors and/or approximations. Although most of the noise in a camera come from photonic noise (and can’t be reduced by sensor cooling)
Source for ISO :
http://www.dxomark.com/About/In-depth-measurements/Measurements/ISO-sensitivity
For Noise :
http://www.dxomark.com/Reviews/Noise-characterization
Tiffany, it’s NOT a “great informational video” The fellow does NOT even understand the source of digital noise. So much of the video is either over-simplified, wrong or both. You should check with an expert you trust and verify the value of articles before recommending them just because the source knows how to draw graphs. There is no relationship between a person’s ability to create a video and having a clue about the subject. (The same could be said of writing articles.) Don’t pass on misinformation!
Electrical cables?…… how do you explain old film cameras?
I beleive Its about photons and how on a high iso, you are only collecting a low number of photons worth of information, and boosting their value. Same as night vision with the glowy sparkles effect, those are photons hitting the sensor.
Someone, feel free to correct me, but I think thats right.
I heard that the noise in digital cameras is because of the receptors getting more sensitive to possible heat sources and thus creating pixels that shouldn’t be there. I also heard that in film cameras, the noise comes from how powerful the photosensitive surface is. I might be wrong because I was mostly sleeping during the class in which the teacher talked about ISO, but I think that’s what it is. Then again I’m also willing to get corrected if I’m wrong.
In film cameras, it’s not called noise; it’s grain, and it’s the result of larger silver halide crystals in the faster film.
Riiight, I knew about what it’s called, just forgot it for a moment. Thanks for the correction.
Yea, I shot Kodak TMax 3200 at a rock concert and pushed it two stops to 12800 and had it push processed at the lab; it maxed the ISO of my Canon A-1. The grain exploded, there were some useable images that were grainy. I just had to accept the grain as part of the process.
This is terrible, as “informational” videos go … I seriously doubt that someone who has no prior understanding of the noise issues will know anything useful at the end (which would be the whole point of an “informational” video, I believe)