Actually, going from 2.8 to 1.4 is two stops, representating 400% as much light as f2.8, a huge difference IMO. So F1.8 vs F2.8, the amount of light ratio is (2.8/1.8)^2=242%. You can see the effect by changing your shutter speed from 1/100 to 1/40.

Because some of us also make money using them for photography. Plus things might change with the Mark III. I don't think the issue with kit lens is its sharpness (thanks for correcting that Perrone), I think the issue is its versatility, color, rendering. Study up on antique glass. You can get stuff down to 1.4 afford-ably and have the option to shoot in the dark. You can also find a lot of glass that doesn't have aperture stops that click, so you can smoothly change your exposure.

Then there is the investment, kit lenses don't have very good resell value. You buy glass thats worth it and you sell it for more than you bought it for in five years. Tyson, looks good to start. If I had done it over again I would have studied below, but maybe its not worth the time it takes: Manual Focus Lenses

Why "no"? Why do guys like Shane hurlbut push this stuff? I understand the debate that a competent photographer/videographer should be able to do something great, even with a p&s.

Still Lenses That Can Grace The Big Screen | Hurlbut Visuals

Understood. The OP made careful comment that this was not a need he had. Thus my question to him. I use my lenses for both photography as well as video, but for someone who does not have the need, the purchase decision might well be different.


Hurlbut doesn't push "L" glass. He doesn't like it and neither do I. Hurlbut likes Nikon glass and I have a bunch of it. He has Zeiss glass, I don't care for it and couldn't afford it even if I did. Hurlbut is also making 10x - 50x what I make on a shoot and his needs are different than most people here. Very few people here are doing work that will end up on broadcast TV or in the local Cinemaplex. I've seen what Nikon, Canon L, Canon non-L, and some other glass looks like on our screening theater (28ft screen) and at the theater where we premiered which is bigger than 42ft. I was pleased with the look of the Nikon glass far more than the other glass. For out next film we used the Nikon glass more.

Pay close attention to the people who are complaining about aliasing and Moire. And notice how many of those folks are using ultra-sharp glass like the Compact Primes and the "L" glass. Then see comments from the vintage glass shooters. You barely hear anything about these issues. In my opinion, based on what I've shot and what I've seen shot, the very sharp glass causes more problems than it solves, and costs a small fortune to boot. So I don't recommend them. If others like them and want to shoot it, that's fine.

For me these reviews only go so far. At some point, you've just got to put the glass on your own camera, and go see what it does.

2.8 is the magic number.
 

Thanks to everyone included, I now understand that f/2.8 is what i must be going for for video. Man, i cant believe how dumb i was 2 days ago! Anyway, I'm now adjusting and looking at the Tamron 17-55mm f2.8 lens as a primary lens i might use often. -As used it sells for only $400. ($800 new)

I would say the line up of lenses you want/plan to buy should have an impact on whether or not to get the 18-135 kit. If you initially want to buy some fast primes then get the kit, use it, and start buying primes. If the first lens you want is a 17-50/18-55 f2.8 then use the $100 toward that lens.I have many lenses and my 17-50 2.8 is on my camera almost exclusively when it comes to video. For stills I favor my primes.

Tyson I use the Tamron 17-50 2.8 and NEVER take it off my camera. I have the OS/IS version and got it for $650 with a $50 rebate. Tamrons are known to be optically better than Sigma but rarely have an autofocus system as good. With video autofocus is pointless so it was a no brainer to me. And a grand for the canon is simply laugh worthy.