Okay, well I'm about to buy my first DSLR and i've been waiting for a month or 3
(been tracking this site on and off for 3 months aswel) for this one to arrive, which wasn't too bad since i wasn't in a hurry anyway. I have used a few Canon rebels before and hence the reason i wanted to buy one, the experience and the opportunity to swap lenses between one another.
from here on out i'll explain my choices based on my (perhaps wrongly) attained knowledge gained from browsing and reading up on camera gear.
So from the information i've gathered it would be wise to go for prime lenses since they "teach" you to become a better photographer, besides i'll use this camera for video shooting aswel and since I use a glidecam HD1000 zooming with lenses completely throws it off balance again. Also i was under the impression that the "kit" lens hardly delivers the quality that the t4i body has to offer, thus i thought investing in primes is a great way to get all the quality out of the body.
I wanted to buy a Sigma 10-20mm F/4 - 5.6 Mainly for action shots combined with the glidecam (Didn't want to go for a fisheye due to it being way overused in the parkour scene)
A Canon 35mm F/2.0, mainly for portraits. The reason for this is my friend complaining about his Canon 50mm F/1.8, it's great but just not so practical in small rooms due to the crop sensor on his T2i.
To cover some more range i thought investing in either a Canon 85mm / 100mm (prime).
The reason for posting it in this specific topic is, well mainly for the next question. The sensor seems the same but the ISO has been upped to 25600. From my (little) experience using the camera at 1200 or higher gets you real grainy pictures right? So what's the use from upping it from 12800 to 25600 that's shitloads of grain we're talking about right?
Or is the ISO performance improved on this body by using DIGIC V+?
Hope you can help me out here

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