Canon digital SLR question

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Date: 29 Aug 2006 18:57:23
From: Joe S.
Subject: Canon digital SLR question

I have two Canon film cameras -- EOS 630 and EOS Rebel-G. When the shutter
trips, the mirror flips up and down and the film advances all of which is
LOUD and noisy.

What happens when you trip the shutter in a digital SLR?? Obviously the
film doesn't advance but do you still get the mirror slap noise?

I'm looking for a quiet camera and it looks as though I'll have to go
backward in time to an old viewfinder camera or forward to the present to a
viewfinder digital.

Date: 30 Aug 2006 00:25:00
From: Sam Wormley
Subject: Re: Canon digital SLR question

Date: 29 Aug 2006 18:59:59
From: S. Caro
Subject: Re: Canon digital SLR question

Joe S. wrote:

> I'm looking for a quiet camera and it looks as though I'll have to go
> backward in time to an old viewfinder camera or forward to the present to a
> viewfinder digital.

The only bad thing about non SLR digitals is that they have poor
performance at high ISO settings. If you plan on shooting ISO 400
or higher, the SLR's come out ahead. They have better (larger) sensors.
(For some reason they *won't* put the same sensors in non DSLR cameras).
Just for comparison, the average DSLR has an APS-C sized sensor. The
average rangefinder style camera has a sensor about 1/2 the size of
your little fingernail.

The larger sensor allows for larger sensor sites which can gather more light
than the tiny sites on smaller sensors.

Since the sites gather more light, they don't require as much amplification
and less amplification results in less noise.

If you plan to shoot ISO 200 and lower, then a digital rangfinder style
camera will be OK.

Date: 30 Aug 2006 01:46:52
From: CW
Subject: Re: Canon digital SLR question

Does this mean the Canon 300D (7.3um pixels) is more sensitive than the
350D(6.2um pixels)?

I am thinking of getting a cheap 300D or wait for the Rebel XTi.

CW

Date: 30 Aug 2006 13:03:56
From: Chris L Peterson
Subject: Re: Canon digital SLR question

On Wed, 30 Aug 2006 01:46:52 -0400, CW <CW@aol.com > wrote:

>
>Does this mean the Canon 300D (7.3um pixels) is more sensitive than the
>350D(6.2um pixels)?
>
>I am thinking of getting a cheap 300D or wait for the Rebel XTi.

Sensitivity is determined by S/N. The larger pixels on the 300D sensor
can hold a larger charge than those of the 350D, which is good. But the
newer 350D sensor has better noise specs. When you combine these, it
turns out the 350D has a little higher S/N- that is, better sensitivity.

That said, the 300D has excellent performance (certainly, it already has
more pixels than most people need for astroimaging). If you are looking
for a DSLR, it is going to be hard to beat in terms of value.

_________________________________________________

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

Date: 29 Aug 2006 16:27:56
From: laura halliday
Subject: Re: Canon digital SLR question

Joe S. wrote:
> I have two Canon film cameras -- EOS 630 and EOS Rebel-G. When the shutter
> trips, the mirror flips up and down and the film advances all of which is
> LOUD and noisy.
>
> What happens when you trip the shutter in a digital SLR?? Obviously the
> film doesn't advance but do you still get the mirror slap noise?

Yup. You get the mirror and the shutter noises, just like a film
SLR. Some DSLRs have mirror lock; I reflashed my Digital
Rebel to add the feature.

> I'm looking for a quiet camera and it looks as though I'll have to go
> backward in time to an old viewfinder camera or forward to the present to a
> viewfinder digital.

My quietest camera is my Crown Graphic. Leaf shutter,
rangefinder focusing. Actually, all my vintage leaf shutter
cameras are very nearly silent, just a soft click.

My noisiest camera is my Pentax 67. Huge mirror, huge
shutter. Thwup...ka-CHUNK!

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

Date: 30 Aug 2006 06:45:53
From: whowell
Subject: Re: Canon digital SLR question

laura halliday wrote:
>
> Yup. You get the mirror and the shutter noises, just like a film
> SLR. Some DSLRs have mirror lock; I reflashed my Digital
> Rebel to add the feature.
>
Laura....

"reflashed"--??

Can you explain that a bit?

Wayne Howell
Photon Phlats Observatory
Port Townsend, WA

Date: 30 Aug 2006 13:55:00
From: Chris L Peterson
Subject: Re: Canon digital SLR question

On Wed, 30 Aug 2006 06:45:53 -0700, whowell <whowell@gensearch.com >
wrote:

>"reflashed"--??
>
>Can you explain that a bit?

There is a free, independently produced firmware update (a hack if you
prefer) for the 300D that activates most of the features found in the
10D (mirror lock, flash exposure comp, and others). It is highly
recommended if you have a 300D, whether you use if for astroimaging or
ordinary photography.

The hack is very safe, and completely reversible. See
http://www.bobatkins.com/photography/digital/digital_rebel_firmware_hack.html

_________________________________________________

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

Date: 30 Aug 2006 13:48:37
From: Sam Wormley
Subject: Re: Canon digital SLR question

whowell wrote:
> laura halliday wrote:
> >
>> Yup. You get the mirror and the shutter noises, just like a film
>> SLR. Some DSLRs have mirror lock; I reflashed my Digital
>> Rebel to add the feature.
>>
> Laura....
>
> "reflashed"--??
>
> Can you explain that a bit?
>
> Wayne Howell
> Photon Phlats Observatory
> Port Townsend, WA

Updated firmware in flash memory.

Date: 30 Aug 2006 17:40:41
From: Craig M. Bobchin
Subject: Re: Canon digital SLR question

Wayne,

Laura means that she upgraded her camera's rom with a newer version of
the firmware to add features that would normally be inaccesable. Google
digital reble russian firmware hack to get the info on all that it can
do and the instructions on how to upgrade the firmware in the camera.

Craig

In article <YKydndgBdtHVC2jZnZ2dnUVZ_qidnZ2d@cablespeedwa.com >,
whowell@gensearch.com says...
> laura halliday wrote:
> >
> > Yup. You get the mirror and the shutter noises, just like a film
> > SLR. Some DSLRs have mirror lock; I reflashed my Digital
> > Rebel to add the feature.
> >
> Laura....
>
> "reflashed"--??
>
> Can you explain that a bit?
>
> Wayne Howell
> Photon Phlats Observatory
> Port Townsend, WA
>

Date: 30 Aug 2006 16:37:07
From: Rich
Subject: Re: Canon digital SLR question

Date: 30 Aug 2006 13:29:44
From: laura halliday
Subject: Re: Canon digital SLR question

Craig M. Bobchin wrote:
> Wayne,
>
> Laura means that she upgraded her camera's rom with a newer version of
> the firmware to add features that would normally be inaccesable. Google
> digital reble russian firmware hack to get the info on all that it can
> do and the instructions on how to upgrade the firmware in the camera.
>
> Craig

Yup. Apparently Canon use the same source code base
for both the 10D and the 300D (aka Digital Rebel). Some people
figured out that by changing a couple of flags in the image,
you could enable many 10D features on a 300D.

Many of them work; some don't. The only one I have
any real use for is mirror lockup.

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

Date: 30 Aug 2006 10:53:13
From: Don't Be Evil
Subject: Re: Canon digital SLR question

Date: 30 Aug 2006 18:06:19
From: Chris L Peterson
Subject: Re: Canon digital SLR question

On 30 Aug 2006 10:53:13 -0700, "Don't Be Evil" <g626700-gg@yahoo.com >
wrote:

>There are still some "prosumer" fixed-lens digital cameras out there.
>Sony has one with an APS-C sized sensor. Still not a DSLR.

Regardless of the sensor quality, fixed lens cameras are generally poor
choices for astroimaging. A fixed lens camera requires an afocal imaging
setup, which introduces a variety of problems. The ability to place the
sensor at the focal plane of the telescope is very valuable.

That's not to say you can't make a fixed lens camera work, but with
DSLRs available at very reasonable prices, there is little reason to do
so unless you are only a very casual astroimager.

_________________________________________________

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

Date: 30 Aug 2006 11:43:20
From: Tim Killian
Subject: Re: Canon digital SLR question

Joe S. wrote:
> I have two Canon film cameras -- EOS 630 and EOS Rebel-G. When the shutter
> trips, the mirror flips up and down and the film advances all of which is
> LOUD and noisy.
>
> What happens when you trip the shutter in a digital SLR?? Obviously the
> film doesn't advance but do you still get the mirror slap noise?
>
> I'm looking for a quiet camera and it looks as though I'll have to go
> backward in time to an old viewfinder camera or forward to the present to a
> viewfinder digital.
>
>

Cannon is claiming the XTi will have sensor noise less than or equal to
the XT. They accomplished this by slimming down the filler areas between
pixels and making the microlenses smaller. This allows the smaller
pixels to achieve the same S/N ratio as the larger pixels used in the XT.

I too was considering a 300D, but now that the XTi is announced, I think
I'll wait a few weeks and go with the more modern features available in
that model, DigicII processor, self-cleaning sensor, magnifier option on
the LCD (like the 20Da), mirror lock up, etc.

http://www.imaging-resource.com/PRODS/XTI/XTIA.HTM

Date: 30 Aug 2006 23:57:05
From: G.T.
Subject: Re: Canon digital SLR question

Tim Killian wrote:
> Joe S. wrote:
>
>> I have two Canon film cameras -- EOS 630 and EOS Rebel-G. When the
>> shutter trips, the mirror flips up and down and the film advances all
>> of which is LOUD and noisy.
>>
>> What happens when you trip the shutter in a digital SLR?? Obviously
>> the film doesn't advance but do you still get the mirror slap noise?
>>
>> I'm looking for a quiet camera and it looks as though I'll have to go
>> backward in time to an old viewfinder camera or forward to the present
>> to a viewfinder digital.
>>
>
> Cannon is claiming the XTi will have sensor noise less than or equal to
> the XT. They accomplished this by slimming down the filler areas between
> pixels and making the microlenses smaller. This allows the smaller
> pixels to achieve the same S/N ratio as the larger pixels used in the XT.
>
> I too was considering a 300D, but now that the XTi is announced, I think
> I'll wait a few weeks and go with the more modern features available in
> that model, DigicII processor, self-cleaning sensor, magnifier option on
> the LCD (like the 20Da),

This is the second time I've seen this mentioned but I see nothing in
the previews so far that confirms this.

Greg

--
"All my time I spent in heaven
Revelries of dance and wine
Waking to the sound of laughter
Up I'd rise and kiss the sky" - The Mekons