Canon D300 and Digital Rebel questions

Hi Guys:

Once again, a few quick questions about this/these camera(s). I don't make
the differentiation here because I'm wondering- is the D300 and Digital
Rebel the same or different camera(s)?

Whatever the case may be, is/are the lens(es) removable?

What bit digital converter does the/each camera have (8 bit, 16 bit, etc)?
Not talking about the images it works with because I've seen some cameras
output images in a higher bit than the actual converters.

Finally, what makes the camera(s) appealing to astronomy?

Thanks,
-Ryan Walters

I lost 127 pounds five years ago on the Atkins diet. A low carb diet IS the
way to eliminating the type II diabetes epidemic.

On Thu, 22 Jul 2004 17:52:36 GMT, "Ryan Walters"
wrote:

Once again, a few quick questions about this/these camera(s). I don't make
the differentiation here because I'm wondering- is the D300 and Digital
Rebel the same or different camera(s)?

Same camera. It is marketed in the U.S. as the Digital Rebel, most everywhere
else as the 300D.


Whatever the case may be, is/are the lens(es) removable?

Yes, it is a standard SLR that accepts all Canon lenses (and third party
versions)..


What bit digital converter does the/each camera have (8 bit, 16 bit, etc)?
Not talking about the images it works with because I've seen some cameras
output images in a higher bit than the actual converters.

The conversion is 12-bit (as are the raw files produced), and based on my noise
measurements it seems to actually have the expected 1:4K (72dB) dynamic range,
unlike some cameras that output more than eight bits.

Finally, what makes the camera(s) appealing to astronomy?

Primarily, the very low noise of the detector. It is quite possible to make
5-minute exposures with this camera, which when combined with stacking allows
for excellent quality images.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Chris,
is it true that there is an upgraded CMOS detector now available giving more
megapixels in a larger size chip? I recall seeing this in an ad in the magazine
Aperature.
Bill Bambrick
41 N, 73 W, 95 ASL

On 22 Jul 2004 19:35:57 GMT, (Jb2269) wrote:

Chris,
is it true that there is an upgraded CMOS detector now available giving more
megapixels in a larger size chip? I recall seeing this in an ad in the magazine
Aperature.
Bill Bambrick

Canon has an 8MP sensor. I've heard from a few early adopters that it doesn't
perform as well as the 6MP chip, and some people are going back to their 10Ds.
Whether that is a problem with the sensor or the camera, however, I don't know.

Personally, I'm in no hurry for more pixels. At 6MP the 10D is already
outperforming film in terms of resolution, and I like the slightly smaller
sensor dimensions, as it allows much less expensive lenses to operate in their
central sweet spots. A US$250 lens performs as well with the 10D as a US$800
lens with film (better, actually, considering the better sensor MTF compared
with film).

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Ryan Walters wrote:
Hi Guys:

Once again, a few quick questions about this/these camera(s). I don't make
the differentiation here because I'm wondering- is the D300 and Digital
Rebel the same or different camera(s)?


Yes.

Whatever the case may be, is/are the lens(es) removable?


Yes -- a true DSLR

What bit digital converter does the/each camera have (8 bit, 16 bit, etc)?
Not talking about the images it works with because I've seen some cameras
output images in a higher bit than the actual converters.


Does not compute. It has a 6 megapixel CMOS imager and can produce RAW
or jpeg images.

Finally, what makes the camera(s) appealing to astronomy?


Can be used at prime focus using a T-mount: Telescope IS the lens.

Phil

Thanks, Chris -- better reply than mine.

Phil

Chris L Peterson wrote:

On Thu, 22 Jul 2004 17:52:36 GMT, "Ryan Walters"
wrote:


Once again, a few quick questions about this/these camera(s). I don't make
the differentiation here because I'm wondering- is the D300 and Digital
Rebel the same or different camera(s)?


Same camera. It is marketed in the U.S. as the Digital Rebel, most everywhere
else as the 300D.



Whatever the case may be, is/are the lens(es) removable?


Yes, it is a standard SLR that accepts all Canon lenses (and third party
versions)..



What bit digital converter does the/each camera have (8 bit, 16 bit, etc)?
Not talking about the images it works with because I've seen some cameras
output images in a higher bit than the actual converters.


The conversion is 12-bit (as are the raw files produced), and based on my noise
measurements it seems to actually have the expected 1:4K (72dB) dynamic range,
unlike some cameras that output more than eight bits.


Finally, what makes the camera(s) appealing to astronomy?


Primarily, the very low noise of the detector. It is quite possible to make
5-minute exposures with this camera, which when combined with stacking allows
for excellent quality images.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Only in the Canon 1D MkII (abt $4K).

But watch for announcements of new goodies this Fall.

Jb2269 wrote:

Chris,
is it true that there is an upgraded CMOS detector now available giving more
megapixels in a larger size chip? I recall seeing this in an ad in the magazine
Aperature.
Bill Bambrick
41 N, 73 W, 95 ASL

I have been reading that the 300D cannot lock its mirror into place,
which introduces extra vibration, whereas the 10D can do this (10d is
the next version up from the digital rebel) This is important to both
astrophotography (which i hope to get into) and telephoto and macro
photography (which the wife wants to get into). Anyone have any
direct experience with this. Trying to justify the extra few hundred
dollars the 10D costs over the 300D.

Also, if anyone has used this specific camera for astrophotography
wants to give some general impressions, please do so.

On Sun, 25 Jul 2004 14:36:49 GMT, Fu Manchu wrote:

I have been reading that the 300D cannot lock its mirror into place,
which introduces extra vibration, whereas the 10D can do this (10d is
the next version up from the digital rebel) This is important to both
astrophotography (which i hope to get into) and telephoto and macro
photography (which the wife wants to get into). Anyone have any
direct experience with this. Trying to justify the extra few hundred
dollars the 10D costs over the 300D.

It is trivial to modify the 300D firmware and activate the Custom Functions menu
of the 10D (which is part of the 300D software, but simply disabled). Once you
do that, you regain the ability to lock up the mirror. The mirror lock works a
little differently than on the 10D, since you set it to flip some programmed
time before the exposure starts, but that's all you need for astroimaging and
telephoto shots. The mod adds some other nice features like flash exposure
compensation, too.

Details are at
http://www.bahneman.com/liem/photos/...el-tricks.html . There is
nothing unsafe about performing this firmware change. It uses the Canon standard
method for reprogramming the camera, and you can download and reinstall the
original firmware if you should want to. For all practical purposes, this
changes a 300D into a 10D with a slightly different user interface (and a
plastic body, of course).

Highly recommended.


Also, if anyone has used this specific camera for astrophotography
wants to give some general impressions, please do so.

Well, it is still limited by the color accuracy problems that face all cameras
using color detectors, but the noise level is low and overall the camera does a
quite good job. I would never consider it as a primary astroimaging tool, but if
you are looking at this camera for more conventional use (and it is stunningly
good for that) there is no reason at all not to use if for astronomical imaging.
You can expect very pleasing results.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

There are folks using the 300D for astrophotography. Check out the
dpreview 300D forum for more info.

There is also a hack to the 300D firmware which adds mirror lock up
(MLU). Do a Google seach for Wasia -- the name of the Russian developer.

I would provide links, but my broadband access is down, making such
things more tedious than normal.

Phil

Fu Manchu wrote:
I have been reading that the 300D cannot lock its mirror into place,
which introduces extra vibration, whereas the 10D can do this (10d is
the next version up from the digital rebel) This is important to both
astrophotography (which i hope to get into) and telephoto and macro
photography (which the wife wants to get into). Anyone have any
direct experience with this. Trying to justify the extra few hundred
dollars the 10D costs over the 300D.

Also, if anyone has used this specific camera for astrophotography
wants to give some general impressions, please do so.