More on Canon Rebel XT noise at high ISO - 2 main new data points

I went to another camera store earlier this afternoon mainly
to look at the Canon 430 external flash, which I did buy.

While I was there, I talked to the manager, whom I know well
and trust, about the (apparent) noise I'm seeing with my XT.
Like most everyone else, he was incredulous, then strongly
suggested that my particular camera was defective, as his
experience was 100% the opposite.

Since I had my camera around my neck, I asked if I could try
one of his, that he knew to be working correctly. "Sure, have
at it!". So, I pumped off about 30 shots, some with the built-
in Speedlite and some available light, across subjects with a
lot of detail and both light and dark backgrounds (the latter
to better pick up any inherent noise).

When I got home, I took another series of pictures with my own
camera, then loaded the whole mess onto all 3 of my PCs. One
of my PCs is quite old, still running Win 98, with a 17" CRT
with brightness and contrast cranked down because my wife says
the glare hurts her eyes. The 2nd one is my old Win XP SP1
machine, also with a 17" CRT that I know is showing images too
dark. Finally, I put them on my new Win XP SP2 box with a 21"
Samsung LCD which I know is properly calibrated for both
brightness/contrast and RGB. Please don't go off on the
monitors, just yet, OK?

By this time of day (4:15PM EST), my fav store manager had
left for the holiday weekend, so I'll talk to him on Monday.
But, the bottom line is this, 2-fold:

1) /Both/ camera's, my "defective" one and his "working" one
showed the /same/ amount of noise at /all/ ISO from 100 to
1600 on /all/ 3 of my PCs. Naturally, no noise is readily
apparent until ISO 400 on both cameras.

2) Despite being careful on Programmed Auto in both flash and
available light, some of the pics I took with the store's
camera and pics I took in my house with my own, are a stop or
2 underexposed. Please don't debate this yet, either. The more
the underexposure, the higher the noise. Well, Duh?! I already
knew that, and that explains the extra noise I got Wednesday
at the WPC Museum - but which I've already explained I
understand.

I /will/ investigate this further, you can trust. But, so far,
it still looks like the medium 5.5 MP images saved on both
cameras with the highest quality (least JPEG compression)
/all/ show about the same amount of noise.

As I do not understand RAW, and do not have Canon's RAW
converter on my PC to avoid invalidating the store's return
policy, I cannot evaluate that. Suffice to say that there /is/
a problem with the Rebel XT - from my perspective.

Now, you can all write me off as just another
nutbag/troll/incompetant/inexperienced/closed minded/asshole
if you like. But, as the saying goes "I don't know anything
about art, but I know what I like." And, I recognize noise
when I see it, as well as I understand what makes it worse.

Calm, rationale, non-insulting comments are welcomed. Insults
to me or my intelligence will be ignored. And, please
everyone, have a very Happy New Year!

--
ATM, aka Jerry

"I disagree with what you say, but I will defend to the death
your right to say it." - Evelyn Beatrice Hall under the
pseudonym Stephen G. Tallentyre