Catpiano

Oh man ..  how can we help you?

they are so diff ..  

It is like asking ..  should I buy a Honda CRV or a Lotus Elise ??

5D is by far more then just $1K over 450D  

5D is like $2,500  and 450D is around $700

Same old question to ask you, why you need a DSLR?  what kind of pic u like? how is your PS skill? you like pic just fresh off from the DSLR, and print? or you like to do some editing??

Yes .. from NUMBER ..  they both 12/13MP  but they are so different ( like CRV and ELISE, they are close in horse power )

Catpiano

Then narrow it down to 40D    more a in between camera ..  

Again, which body ..  doesn't matter .  body may be just 10-20% of the system ..  

Size ..  build quality ..  material .. ( metal body vs plastic )

If you are quite new to photography, then FF or 1.6x .  probably won't make much different  ..  actually 1.6x 450D (or 40D) may be better for you, since you can buy much lower cost EF-S lens and other lens..  (ie $100 to buy a 50 F1.8 on a 1.6x body, vs $500 to buy a 85 F1.8)

Catpiano

Yeah .. just like compare FF to MF ..   

With film .. then of course, the bigger .. is better .. 645 .. 66 .. 67 .. can hv more detial and control over 35mm ..  and 35mm is better then aps size ...  

However, now in the digital sensor age ..   most ..  most users .. dont even know what is "35mm standard"  nor even 2x3 ratio .. (of course, not even MF  LF format ... )

So ..  for a 10 MP sensor ..  no matter it is 35x 24 or 24x16 ..  it doesn't matter to many people ..  as long as when they blow up the pic .. the "density" of pixel is about the same anyway ..

[ 本帖最後由 Catpiano 於 2008-3-7 12:11 編輯 ]