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Canon Digital Rebel Questions



 
 
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  #1  
Old December 29th 04, 12:21 AM
J C
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Default Canon Digital Rebel Questions

Thanks for the responses.
If the price is right I think I'll pick one up.
Laura: where did you purchase yours?

John C.

  #2  
Old December 29th 04, 12:25 AM
Bill Becker
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I saw one at the local Sam's Club for ~US$850.

Best regards,
Bill
"J C" wrote in message
...
Thanks for the responses.
If the price is right I think I'll pick one up.
Laura: where did you purchase yours?

John C.



  #3  
Old December 29th 04, 01:15 AM
Bill Becker
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And here's a better place to get one:
http://www.buytelescopes.com/product...&pid=6313&m=45

Best regards,
Bill

PS: Price should never be the sole reason for choosing where to buy. ;^)
"J C" wrote in message
...
Thanks for the responses.
If the price is right I think I'll pick one up.
Laura: where did you purchase yours?

John C.



  #4  
Old December 29th 04, 02:02 AM
Chris L Peterson
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On Tue, 28 Dec 2004 23:21:32 -0000, J C wrote:

Thanks for the responses.
If the price is right I think I'll pick one up.
Laura: where did you purchase yours?


I can highly recommend Butterfly Photo, http://www.butterflyphoto.com . I bought
one there, and in the last few months three of my friends have. $689 after the
$100 rebate, for the kit with the 18-55mm lens (it is a nice lens- I recommend
you get it for the tiny additional cost it adds). You can knock another $100 or
$200 off that if you plan on buying any of the Canon lenses on the rebate list.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
  #5  
Old December 29th 04, 06:48 AM
laura halliday
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I bought my Digital Rebel at my favourite local professional camera
store (Leo's Cameras, Vancouver): the usual kit with the body and 18-55
lens, plus a 512 MB compact flash card. I know I could have gotten it a
bit cheaper from Anacortes or B&H, but there is something to be said
for local support and backup.

I also picked up an EOS T ring this afternoon (Vancouver Telescope
Centre) and tested it by taking pictures of the mountains through a
couple of my refractors. Sadly, Mother Nature had other ideas this
evening. :-(

Laura Halliday VE7LDH "Que les nuages soient notre
Grid: CN89mg pied a terre..."
ICBM: 49 16.05 N 122 56.92 W - Hospital/Shafte

  #6  
Old December 29th 04, 07:48 PM
J C
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There are some good deals, thanks.
How long does the battery last?

John C.
  #7  
Old December 29th 04, 08:00 PM
Chris L Peterson
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On Wed, 29 Dec 2004 18:48:51 -0000, J C wrote:

There are some good deals, thanks.
How long does the battery last?


I average about 400 shots. That's with a 4-second image preview time, limited
use of the flash, and normal lenses. It goes down to about 300 shots with an
image stabilized lens. It doesn't seem to use much power to hold the shutter
open- after 30 5-minute images at -10C the battery indicator still shows a full
charge.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
  #8  
Old December 29th 04, 08:21 PM
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J C wrote:

I'm debating about whether to buy one.
What is the longest useful exposure one can use at room

temperature(around
20 C)?


Canon 10D: 4921 seconds is my maximum. You can see the results at
www.photo.net; click on the "Dark noise calibration" article, and
scroll down to the comment section for a 4x4 grid of (underexposed)
images.

I did the experiment when someone in rec.photo.digital was blabbering
about how horrible digital sensors were at long-exposure photography.
I _EXPECTED_ crap.

I was _amazed_ at what I got.

  #9  
Old December 29th 04, 08:35 PM
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Chris L Peterson wrote:

The camera has a bit

better
than 11 bits of dynamic range for a short exposure. I figure that

drops about
one bit (or a factor of two) for every 5 minutes of exposure.


Do you have any evidence for this claim?

I have a 4921 second exposure taken with a Canon 10D: looks basically
fine to me (it's of course not the best one can get). Your 'logic'
says this is flatly impossible: 90/5 = 18 bits, which exceeds the
cameras DR by 6 bits.

Uncle Al says: "When physical reality says you are an ass, you are an
ass".

Here is your chance to make me look stupid: do the experiment yourself
and report the results. It's so simple; whatever is the delay?

  #10  
Old December 29th 04, 08:51 PM
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J C wrote:

How long does the battery last?


I posted this to rec.photo.digital on 2004 Nov 12; it's for a Canon
10D, but the internals are probably similar to a Rebel/300D. I used an
EF 500/4 lens as the "worst case", but found that lense choice wasn't
much important. Do not be too alarmed by the "peak" figures, as these
are generally brief events (and subject to alot more measurement
noise).

Battery life: I use a pair of no-name 1400mAH(?) BP-511's. I can fill
about 3GB of space (about 500 "raw" images) before I need to change
batteries. I tend to "hang" alot on the IS, and do alot of in-camera
editing (LCD display).

I would recommend the 20D for a new camera buy. More expensive, but
better electronics -- particularly the AF system -- and features
(firmware glitches notwithstanding). In fact, it looks like the 20D
has the same internals as the 1D MkII, just re-arranged and down-sized
(reduced pipeline size, etc).

- - - -

Here are some current measurements of a Canon 10D. The power supply
was a single, full-charge, 3rd party BP-511, 8.2V. Various
operations:

off 0mA (probably something in the microamp area)

idle 98mA

active 406mA (shutter half-press; exposuring ongoing)
388mA (no shutter button contact)
421mA IS only \
672mA IS + AF shutter half-pressed
665mA AF only /

AF measurements are "peak".

imaging 1150mA (peak - _very_ brief)

editing 250mA/315mA \ LCD bright
233mA |
214mA
195mA |
186mA/250mA / LCD dim

writing 150mA (with bursts of 220mA)

bulb 345mA (holding the shutter open in 'bulb' exposure)

The lens was an EF 500/4, but others (EF 20/2.8, EF 300/4) didn't
change much. Note the relatively low impact of using IS, and the
large impact of the AFing (the lens was racking from close to
infinity). Also note the low image write current.

Peak current of 1.15A was measured during a 9 "raw" frame pipeline
fill/drain episode. This peak was unaffected by IS or AF, suggesting
that it is still an underestimate (unlikely given the Fluke meter I
was using), or that AF (the larger of the two) is briefly disabled
during mirro flip, shutter open, etc. Note that the act of taking a
picture should demand a fair amount of energy given how fast these
moving parts are moving.

 




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