«

Hi,

I was reading an article and one of the points of dSLR with small
sensors (such as 1.5 conversion factor) was that an 300mm/f2.8 becomes
effectively an 450mm f/2.8: the effective focal length (angle of view
changes) but the f number stays the same.

So this ot me thinking: with the low noise of Canon 10D at ISO 1600 and
this increased focal length (from 300 to 450) it should be possible to
take pictures in very dim light, that was not possible before with film.
is that complete bullshit or is it true? Let's ignore IS here, since it
gives you one more stop regardless of what's behind it, film or CMOS...

Wherever did you get the idea 10Ds were "low noise" at ISO 1600?
AJ

"chibitul" <> wrote in message
news:ch1b1tul- ...
> Hi,
>
> I was reading an article and one of the points of dSLR with small
> sensors (such as 1.5 conversion factor) was that an 300mm/f2.8 becomes
> effectively an 450mm f/2.8: the effective focal length (angle of view
> changes) but the f number stays the same.
>
> So this ot me thinking: with the low noise of Canon 10D at ISO 1600 and
> this increased focal length (from 300 to 450) it should be possible to
> take pictures in very dim light, that was not possible before with film.
> is that complete bullshit or is it true? Let's ignore IS here, since it
> gives you one more stop regardless of what's behind it, film or CMOS...

chibitul wrote:

> Hi,
>
> I was reading an article and one of the points of dSLR with small
> sensors (such as 1.5 conversion factor) was that an 300mm/f2.8 becomes
> effectively an 450mm f/2.8: the effective focal length (angle of view
> changes) but the f number stays the same.

Yes.

>
> So this ot me thinking: with the low noise of Canon 10D at ISO 1600 and
> this increased focal length (from 300 to 450) it should be possible to
> take pictures in very dim light, that was not possible before with film.
> is that complete bullshit or is it true? Let's ignore IS here, since it
> gives you one more stop regardless of what's behind it, film or CMOS...

The main point I pull out of your post is that 450mm f/2.8 never existed
before (35mm) so this is new ground ... yeah, sort of. (Using a TC, the
aperture is constant but the FL is longer resulting in a high f. no.).

f/2.8 is better than say f/4.5 but it's not like it has magic light
gathering powers... film or digital...
you are correct on the low noise issue, shooting low (or any) light / hi
iso with the digital will be less noisy than the film counterpart. But
bring a sturdy tripod and use MLU if you can.

What should really blow your socks is a 600mm f/4 becomes a 900 f/4....

Alan.

But by keeping the same density and going to a full size sensor, you
increase the total capability to record an image.

It is much the same as using silver film 35mm and cropping the image, or
just using a full frame digital and cropping it.

--
Joseph E. Meehan

26 + 6 = 1 It's Irish Math


"chibitul" <> wrote in message
news:ch1b1tul- ...
> Hi,
>
> I was reading an article and one of the points of dSLR with small
> sensors (such as 1.5 conversion factor) was that an 300mm/f2.8 becomes
> effectively an 450mm f/2.8: the effective focal length (angle of view
> changes) but the f number stays the same.
>
> So this ot me thinking: with the low noise of Canon 10D at ISO 1600 and
> this increased focal length (from 300 to 450) it should be possible to
> take pictures in very dim light, that was not possible before with film.
> is that complete bullshit or is it true? Let's ignore IS here, since it
> gives you one more stop regardless of what's behind it, film or CMOS...

In article <PDcpb.175949$>,
says...
> Wherever did you get the idea 10Ds were "low noise" at ISO 1600?
> AJ
>

The 10D has lower noise at 1600 than any other DSLR except maybe the
Fuji S2. And high speed film can't even touch the noise performance of
the 10D or S2.

--
________________________________
Todd Walker
http://www.toddwalker.net
Canon 10D:
http://www.toddwalker.net/canon10d
My Digital Photography Weblog:
http://www.toddwalker.net/dpblog.htm
_________________________________

Todd Walker <> wrote:
> says...

>> Wherever did you get the idea 10Ds were "low noise" at ISO 1600?
>
>The 10D has lower noise at 1600 than any other DSLR except maybe the
>Fuji S2. And high speed film can't even touch the noise performance of
>the 10D or S2.

"Lower" is not synonymous with "low". There's a fair bit of noise at
ISO 1600.

--
Ray Fischer

chibitul <> writes:

> I was reading an article and one of the points of dSLR with small
> sensors (such as 1.5 conversion factor) was that an 300mm/f2.8 becomes
> effectively an 450mm f/2.8: the effective focal length (angle of view
> changes) but the f number stays the same.

> So this ot me thinking: with the low noise of Canon 10D at ISO 1600 and
> this increased focal length (from 300 to 450) it should be possible to
> take pictures in very dim light, that was not possible before with film.
> is that complete bullshit or is it true? Let's ignore IS here, since it
> gives you one more stop regardless of what's behind it, film or CMOS...

Well, let's just say that I'm very fond of my 87mm f1.2 NOCT aspheric
portrait lens on my Fuji S2. Very useful at parties.
--
David Dyer-Bennet, <dd->, <www.dd-b.net/dd-b/>
RKBA: <noguns-nomoney.com> <www.dd-b.net/carry/>
Photos: <dd-b.lighthunters.net> Snapshots: <www.dd-b.net/dd-b/SnapshotAlbum/>
Dragaera/Steven Brust: <dragaera.info/>

(Ray Fischer) writes:

> Todd Walker <> wrote:
> > says...
>
> >> Wherever did you get the idea 10Ds were "low noise" at ISO 1600?
> >
> >The 10D has lower noise at 1600 than any other DSLR except maybe the
> >Fuji S2. And high speed film can't even touch the noise performance of
> >the 10D or S2.
>
> "Lower" is not synonymous with "low". There's a fair bit of noise at
> ISO 1600.

Yeah, in the S2 also. But it's still quite useful -- and a *huge*
improvement over what I used to put with using film.
--
David Dyer-Bennet, <dd->, <www.dd-b.net/dd-b/>
RKBA: <noguns-nomoney.com> <www.dd-b.net/carry/>
Photos: <dd-b.lighthunters.net> Snapshots: <www.dd-b.net/dd-b/SnapshotAlbum/>
Dragaera/Steven Brust: <dragaera.info/>

"Joseph Meehan" <> writes:

> But by keeping the same density and going to a full size sensor, you
> increase the total capability to record an image.
>
> It is much the same as using silver film 35mm and cropping the image, or
> just using a full frame digital and cropping it.

Only cheaper.


--
David Dyer-Bennet, <dd->, <www.dd-b.net/dd-b/>
RKBA: <noguns-nomoney.com> <www.dd-b.net/carry/>
Photos: <dd-b.lighthunters.net> Snapshots: <www.dd-b.net/dd-b/SnapshotAlbum/>
Dragaera/Steven Brust: <dragaera.info/>

Alan Browne <> wrote in
news:5Scpb.4088$:

> chibitul wrote:
>
>> I was reading an article and one of the points of dSLR with small
>> sensors (such as 1.5 conversion factor) was that an 300mm/f2.8
>> becomes effectively an 450mm f/2.8: the effective focal length (angle
>> of view changes) but the f number stays the same.
>
> Yes.
>
>> So this ot me thinking: with the low noise of Canon 10D at ISO 1600
>> and this increased focal length (from 300 to 450) it should be
>> possible to take pictures in very dim light, that was not possible
>> before with film. is that complete bullshit or is it true? Let's
>> ignore IS here, since it gives you one more stop regardless of what's
>> behind it, film or CMOS...
>
> The main point I pull out of your post is that 450mm f/2.8 never
> existed before (35mm) so this is new ground ... yeah, sort of. (Using
> a TC, the aperture is constant but the FL is longer resulting in a
> high f. no.).
>
> f/2.8 is better than say f/4.5 but it's not like it has magic light
> gathering powers... film or digital...
> you are correct on the low noise issue, shooting low (or any) light /
> hi iso with the digital will be less noisy than the film counterpart.
> But bring a sturdy tripod and use MLU if you can.
>
> What should really blow your socks is a 600mm f/4 becomes a 900
> f/4....


On the 10D the effective focal length multiplier is 1.6, combined with a
400 f2.8 IS from canon you effectively have a 640mm with f2.8 and IS.
Think about the low light hand held ability of that! (but don’t think
about the cost)

Of course if Canon released a 16MPix full frame D-SLR with the same or
better low noise levels then you still have the same thing because you
could crop and still have 6MPix of data (this is exactly what you get with
the 10D except you don’t have the option not to crop).



--
Mark Heyes (New Zealand)
See my pics at http://homepages.ihug.co.nz/~markh/
"There are 10 types of people, those that
understand binary and those that don't"