I wanna buy a camera that is great quality image, at a good price (no more than $4000), and that the video captured can be watched on a cinema screen (therefore a big depth of field)(i think thats what you call it)...
That's what you call it. And it's not the camera that gives you depth of field, it's the lens.
So you need a camera with a removable lens. Only JVC and Canon offer that in a camera
in your price range. I own the JVC HD110, which I highly recommend. But more people
use and like the Canon cameras so do your research on those, too.
However, there have been several successful movies made in standard def that have been
on the cinema screens.
Inland Empire, Sony PD-150
Open Water, Sony PD-150
The Lost Skeleton of Cadavra, Canon XL-1
28 Days Later, Canon XL-1S
Pieces of April, Sony PD-150
Bamboozled, Sony VX 1000 PAL
Book Of Life, Sony VX1000 (NTSC)
Chuck & Buck, Sony VX1000 PAL
Dancer In The Dark, Sony PD 100 & Sony DXC D30WS PAL
Final, Canon XL-1 PAL
Chelsea Walls, Sony PD100 PAL
Full Frontal, Canon XL1s PAL
Hotel, Sony PD 100 & PD150 PAL
Time Code, Sony DSR-1
Supersize Me, Sony PD150
November, Panasonic DVX 100
My point is, if you make a good enough movie (even using a standard def camera)
it can be good enough to be on a cinema screen.