Keep calm and reverse the malware!
Server issues | Builds page | @autoexec_bin | IRC: #magiclantern
Show Posts
This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.
I'm a gig/event photographer experimenting with dual ISO. It's been great in environments where there is such a strong contrast for things like stage lights and flash work. A couple of examples.
...
The big win for event flash photography is getting more DR in the backgrounds. Especially events like festivals where you notice that background lights colour channels cap out really quickly and everything just looks really smudged. Dual ISO has helped me immensly shooting manual flash in a pinch in this environment too - my TTL flash was stolen a while back and I haven't been able to afford a replacement.
Most of the examples here seem to be scenes which makes sense. We've all seen overexposed skies and can appreciate at a glance how big an improvement we are getting with Dual ISO. I question why most people haven't really discovered it for portrait/event/performance/street style stuff where the loss of detail across the frame matters less and your RAW files has much more flexibility in what you get out of a shot that is just snapped 'in the moment.'
If there is one downside for me though, it's shooting an event (200-400 shots) and leaving them to brew overnight, ultimately costing me 60mb each shot. Here I was thinking that buying a 6D would be a good move to preserve HDD space - hah!
http://www.magiclantern.fm/forum/index.php?topic=10111.0I'll have a look.
In the first post of that thread, also check the section entitled "Any recommended reading?". The DxOMark site will list the dynamic range for all tested cameras.
http://www.magiclantern.fm/forum/index.php?topic=10111.0Estimated DR gained:
ISO 1600 > ISO 3200 may net you 0.4 EV on some camera when you are using standard image capturing. With dual ISO you shouldn't expect to see that result. Each ISO is only half resolution, so you throw away one full stop of (full) midtone resolution, to "gain" 0.4 EV of half resolution shadow detail.
http://www.magiclantern.fm/forum/index.php?topic=10111.0But what if I have an extreme (low light) situation where I may want to use not so usual setting? Such as 800/3200? Does it makes sense? And why do I get only ~0.5EV with that settings?
When you use recommended settings (100/800....100/1600), since the top couple of stops are generally white anyway, the resolution loss may not even be noticed. But when you start using extreme settings (100/3200), you're throwing away another full stop of midtone redolution, and this resolution loss is smack bang in the midtones. You probably want all available resolution for the midtones.
Where you use a low base ISO of say 100, the situation is probably even more dire. Here, you probably have your exposure (shutter/aperture) set for the base ISO. Since ISO doesn't effect shot noise, not only are those last few points of EV only half resolution, but they are also heavy with shot noise.
]The output files contain 16-bit raw data in DNG format, that looks identical to a picture shotOh lol. Maybe I should have read that before. Now it's clear!
in the same conditions at ISO 100. However, this DNG has a lot less noise in the shadows, and
therefore you can push the exposure a lot higher without getting massive noise (+6EV should
be quite clean).
