I just bought a second hand 5D to replace my 20D. While I was waiting for the 5D to arrive I was printing some 8x10s shot with the 20D. After seeing them I wondered if I was nuts to be spending what I did to upgrade. The 20D images looked fantastic.

If you don't intend to print extremely large prints and can live with the limitations of the 1.6 crop sensor the 20D still makes a lot of sense.

A lot of people knows that 30D is a BETTER camera than 40D at high ISO values(ISO 800 and higher)and also they know why(I'm not gonna explain again about how important is a larger pixel).40D only has some new features that for me are totally useless.So,from these four cameras(Canon 10D,20D,30D and 40D) The Canon 30D is the best.

gabimaster wrote:
A lot of people knows that 30D is a BETTER camera than 40D at high ISO values(ISO 800 and higher)and also they know why(I'm not gonna explain again about how important is a larger pixel).40D only has some new features that for me are totally useless.So,from these four cameras(Canon 10D,20D,30D and 40D) The Canon 30D is the best.

+1 .. well said.

gabimaster wrote:
A lot of people knows that 30D is a BETTER camera than 40D at high ISO values(ISO 800 and higher)and also they know why(I'm not gonna explain again about how important is a larger pixel).40D only has some new features that for me are totally useless.So,from these four cameras(Canon 10D,20D,30D and 40D) The Canon 30D is the best.

Owning both the 30D and 40D, I don't see the 30D being better at higher ISO.

and when the 50d comes out the 40d will be crap...

The 30D is a very nice camera, and if I upgrade anytime soon it will be to
get a much larger viewfinder and sensor (i.e. 5D). The files from the 30D look
very good to me. An excellent value on the used market.

Edit:
I will also add that even my XT gets regular use. Yeah, it's only worth
about $250 now, so why bother to sell it? I won't. I use it as my backup
body. The XT has less than great autofocus, but in good light it works well.
With the 35 f/2 it fits in a coat pocket and makes a great combo for a
compact walk-around. Excellent image quality that is comparable to
the 30D at low ISO.

Wouldn't buy a 20D, but the 30D has the same features as the 5D and is pretty cheap nowadays.

OTOH the 30D isn't enough of an improvement IMHO to replace the 20D.

My 20D collects dust, but as a spare and "easy to replace" I'll keep it along.

I am not impressed by the 20D at 800iso, but many others are. If the lighting permits 400iso or better, there is little left to complain. Beats using an extender on my 5D.

Don't understand this gear driven notion that a newer model makes your previous type redundant. The 20D remains relevant until it is kaput!