VC skrev:

First off, I thought both texts were readable - and I downloaded the
30D image first. But yes, the text on the 400D reads slightly easier.

Please note, though, that the 10MPsensors, whether from Canon, Sony or
anyone else, all seem to employ some degree of on-chip noise reduction.
On-chip noise reduction presumably increases with ISO sensitivity. And
small detail with extremely high contrast - such as white text on
black, or vice versa - is less blurred by the effects of noise
reduction than small detail with low contrast.

Thus, the 400D may well be a tad  better at capturing the detail of
high-contrast text than the 30D at ISO100. But it is still a very open
question whether this performance can be generalised  to low-contrast
detail such as fur or foliage, or whether it can be generalised at all
to, say, ISO800.

Jan B?hme

Assuming you mean the white on black text.
The 400D is a bit better in those images, yes.  The CAPS lettering is
readable and the lower case, almost so.
The 30D the CAPS lettering is somewhat readable, the lower case not at all.

10 Mpix is only 11% better resolution than 8 Mpix ... but when you hit a
borderline case (like this) the text goes from 'just readable' to 'not
readable' over that small difference.  Threshold case.

They should both render 8x12's very cleanly and double that if you don't
examine them up too close.

Cheers,
Alan

Splitting digital hairs.
You must live a charmed life if you have nothing better to agonize over than
this piffle.

Regarding enlargement/printing, the difference is pretty insignificant.

If I were you, I'd wait about 4 weeks to see Canon's nearly-certain
replacement of the 30D (February should bring significant
announcements)...and then decide to either wait a month or two for thenew
model...or pick up the outgoing model for less, since prices usually drop at
that point.

Probably the fact that your links are to cameras with different lenses?

More important than any effect near the limit of resolution is what
lenses your are going to use. I purchased the 350D in preference to the
20D or 30D because the difference in price did not make it twice as good
optically, and was enough to purchase an extra lens.

Broadly correct. The 400D (XTi) is the softest-imaging of all the
current 10 megapixel DSLRs - I've tested all of them now. It is probably
designed this way to reduce noise levels. The 30D is a pretty sharp 8
megapixels, because they made changes to lower the level of
anti-aliasing and recover more fine image detail.

If you can afford the 30D, which is a far superior object physically,
there's no contest. I find the 400D colours, contrast and sharpness
quite disappointing but my daughter, who uses it permanently and shoots
stock landscapes and stuff for our library files, is under instructions
never, ever to shoot anything except RAW and it's amazing what Adobe
Camera Raw can do to pep up the results.

David

view it 1:1 and it is much clearer in both cases, viewing at 4:1 is letting
your screen interfere.

You get about 12% more resolution by going from 8 to 10 Mpixels.
Most people wouldn't be able to tell.

I guess you know, eh? No, it is not significantly better. Most people get
fuzzier images with more than 8MP, because higher MP counts magnify motion
blur. It you always use a tripod, 10MP should (in theory) be slightly better,
but you lose some resolution with noise reduction software.

In general, I think most people start taking worse images at anything above
6MP, although 8MP is tolerable. Beyond that, you have to be real careful to
get that last bit of extra performance out of more pixels.

 It's the difference between making a print that's 11.75" wide, and a print
that's 13" wide.

 Whether that is significant to you - and whether it is *more* significant
than the other advantages of the 30D - is up to you.

steve

Yes, the lens and focusing.  What apertures were these shots taken at?
Since there is some depth in the target subject, where precisely was the
focus point?  Was it autofocus, or manual, and if manual, on what
exactly was the lens focused?  Was it even the same lens for both shots?
 There is no exif data to find what lens, what aperture. Were the shots
taken by the same person?  There are just too many variables to be able
to put relative sharpness solely down to the sensor.  Any conclusions
drawn from that comparison are unreliable.

Colin D.

The difference is about 11.2%, big whoop! Go to the better built 30D, or
wait for the soon to be announced 50D