Hi folks !
If I attach my 24-105 in a Rebel T2 or K2, am I going to have a "preview" of what I'll get when I upgrade to a FF ?
I've read that dynamic range in films are greater than digital sensors. How far it's true ?
You'll certainly get a preview of what field of view the lens offers but the actual viewfinder display may or may not be smaller than what you'll get on your future DSLR. The relationship between what you see and how big you see it depends on viewfinder design rather than sensor format.
The DR in some films is greater than that of some digital sensors but other films (e.g. slide) offer much smaller DR. You might argue that digital sensors all have greater DR but in many cases a big chunk of that range is quite useless - just random digital noise with little or no useful image data distinguishable. According to Pondria's DR database the best DSLRs offer about a 9 to 10 stop useful DR while the worst are more like 7 to 8 stops. They're all gradually improving with each new model release but not nearly as fast as the marketing people would have you believe.
Some of what improves DR is built into the in-camera post-capture signal processing but the rest is down to the actual sensor technology. That's why big pixels can still produce more DR than small pixels, and why the likes of the Nikon D3 are so good (but still leave room for improvement).
Film noise is actually grain and is more or less randomly distributed. Digital noise has more pattern to it because the sensor has pixels in fixed locations. Film grain is greatly exaggerated if you scan the film with a digital scanner. The grain is less obvious in a traditional slide viewing than it is in a scanned image. It has to do with the interaction between the actual grain distribution and the scanner sensor pattern.
If you really want to know what you're going to get, then use any camera with a 100% VF. Not only will there probably a subtle yet real improvement in your images, but you'll never want to use one of the "compromised" small VF's again.
And to those saying things like "you get 95% or 96% in a camera like the 5d", just look through a 5d's VF and then through that of a 1 series. There's no comparison, and you'll soon realize that the difference is huge, not just a small thing like the misleading numbers would imply.
