We all know the advantages of having a full-frame sensor. If you don’t, you must have had your head in the sand for what, 3-4 years now? STUNNING high ISO performance, and SEXY HOT bokeh.

However, few people can actually put their finger on real advantages of having a cropped sensor camera. There is price, but that only affects some buyers, plus there are cameras like the 5D that can be had for almost dirt cheap now. Then there is the extra “reach” that you get with a cropped sensor, but that is only an advantage at the telephoto end; it becomes a nuisance at the wide end.

There is one incredible advantage to shooting with a cropped sensor that nobody ever realizes.

Allow me to demonstrate! Here is the viewfinder of the new Nikon D300, with the edges of the outermost focus points outlined:

The un-trained eye will not immediately realize what is so special here. We need to impose the D3 viewfinder on top of the D300′s. Since they are both 100% coverage, this is rather easy:

HOLY TOLEDO, BATMAN!

The D3 and the D300 have the same exact AF module, so yeah, you guessed it- since the D300 is working with a cropped sensor the focus points get pretty darn close to the edge of the frame horizontally. This is a big asset for shooting portraits, and pretty much everything else, even landscape photography… (There you go, the big advantage. Pretty un-exciting, huh? Let me tell you, it makes a difference when you’re shooting!)

On a hunch that this wasn’t just a D3 / D300 thing, I went ahead and compared some Canon DSLR’s. Canon has both 1.6x and full-frame bodies that employ both a 9-point AF system and a 45-point AF system…

Here is the 1Ds series (full frame) viewfinder versus the 1D series: (1.3x)

Not that big of a difference, but it’s probably pretty useful for sports shooters and photojournalists…

Next up, the 40D versus the 5D. This one was a bit tricky, because neither camera has 100% viewfinder coverage- the 40D has 95% coverage and the 5D has 96%… So to show the true “reach” of the focus points, one must lock the viewfinder frame and then shrink the AF points as a whole, within the frame, by the respective percentages:

I thought of posting the D300 versus the 5D, but I’m not even going to go there because the two cameras are not meant to be compared really. I think it is best to just compare cameras that use the same exact AF module.

You can do it yourself in photoshop if you want, but if you own a 5D I’d warn against it, it may cause jealousy. Suffice it to say that the D300 has by far the most horizontal coverage out of any camera on the market. (Which camera has the most vertical coverage, by far? The D2 series’ 11-point AF…) The horizontal coverage in the D300 makes it effortless to snap photos like THIS one. Or any of the 500+ photos I shot this week of children’s theater…

The DX master rests his case.

Actually I would also like to explain how this advantage benefits not only focusing, but metering as well. Next.

=Matt=

PS: Honest, I don’t have some sort of vendetta against full-frame. I drool over the D3 just as much as any other geek. I’m just a real-world shooter who uses cameras as tools, and I enjoy discussing how tools work… If I have any sort of vendetta, it is against those who have a vendetta against DX…