No P&S for a serious hobbyist?

Mike Jacoubowsky wrote:

>>>> Sorry, nothing can be done about small sensors. It seems to be a
>>>> "cartel" decision not to offer decent size sensors in P&S cameras.
>>>
>>> Not exactly. Larger sensors dictate larger lenses. And larger lenses
>>> make for a... bigger camera. Darn, hate those simple laws of physics.
>>>
>>> --Mike-- Chain Reaction Bicycles
>>> www.ChainReactionBicycles.com
>>
>>
>> That's not really correct...
>>
>> There were also a lot of small pocketable cameras in the 35mm-film age,
>> when
>> there were no digital sensors.... And they were able of having things
>> like a 3x zoom and things like that. The lenses weren't really/much
>> bigger than of current pocketable digicams.
>>
>> examples: Fujifilm DL-270 ZOOM, Pentax IQZoom 115, .. just look for
>> compact
>> cameras at ebay
>>
>> --Dennis
>
> Afraid the laws of physics still apply. I took a quick look at the Pentax
> you listed; at wide-angle, the max aperture is F4. The Fuji is even worse,
> at F5. That's how they got the lens size down, no magic involved. If
> you've got a large imaging area (either film or digital sensor), it's
> going to take a correspondingly large piece of glass for the same amount
> of light to hit the sensor.
>
> Small cameras, whether film or digital, simply cannot disobey the basic
> laws of physics. You can make the lens smaller (and thus camera size) by
> either using a smaller sensor or giving up an F stop or two.
>
> Perhaps we could evolve a digital sensor so incredibly sensitive that it
> could be very small and noise-free, such that a lens with a max aperture
> of F8 is all that's needed. That could really get size down! But then I'm
> told there are problems with such a small lens, due to the refraction of
> light at extreme angles (if I've got this right). Did pinhole cameras have
> such
> issues? :>)
>
> --Mike-- Chain Reaction Bicycles
> www.ChainReactionBicycles.com


Yeah, of course the lens will let through less light, but that doesn't mean
it's not possible.

With a bigger sensor you can then push up the ISO, and it will be less
noisy. Of course the lens will let less light through. So in the end you
might have the same, if there wasn't diffraction.

And I also think the factor of the lens letting light through depending on
the image circle is not directly proportional to a sensor being more or
less sensitive to light and being more/less noisy depending on the image
circle it can capture.

I think that it behaves more exponential at sensor size, but linear in lens
size? I'm not sure at all, but to my observation it looks like that (at
least as a rule of thumb).

So, I think, a bigger and more sensitive sensor and slower (letting less
light through) lens will be a better combination than a fast lens and small
sensor. (also because of the diffraction, and yes pinholes can suffer from
diffraction, but if you have a larger format camera it will be less)

--Dennis
 >> Stay informed about: No P&S for a serious hobbyist? 

> So, I think, a bigger and more sensitive sensor and slower (letting less
> light through) lens will be a better combination than a fast lens and
> small
> sensor. (also because of the diffraction, and yes pinholes can suffer from
> diffraction, but if you have a larger format camera it will be less)


So you're proposing an extraordinary sensor that could work at, say, F16 and
deliver great images. One thing's for certain; you'd have great depth of
field! Of course, that can be as much a curse as a blessing.

We need someone with strong knowledge of optics to help us out on this one.
Anyone want to step in?

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com
 >> Stay informed about: No P&S for a serious hobbyist? 

Nobody is saying the there are no physical limitations, only that the
cameras are nowhere near them. What is being offered or withheld is
governed not by physics but marketing decisions.

The 35 mm film cameras had a bigger "sensor", the film itself, than any
digital ps. Lenses, zooming, etc. are not affected by whether the image
is recorded in analog or digital format.
 >> Stay informed about: No P&S for a serious hobbyist? 

RPS wrote:

> Nobody is saying the there are no physical limitations, only that the
> cameras are nowhere near them. What is being offered or withheld is
> governed not by physics but marketing decisions.
>
> The 35 mm film cameras had a bigger "sensor", the film itself, than any
> digital ps. Lenses, zooming, etc. are not affected by whether the image
> is recorded in analog or digital format.


I have long argued that digital photography is in its infancy.

I have tons of Kodachrome 25 tranparancies that I shot with my old,
(well I still have it if I want to get serious), Leica M2. I have a few
scans and believe me, they are the standouts in my screen saver.

Additionally, the tonal range is far greater and I get great detail even
when shooting into the sun late in the afternoon.

OTOH, nothing beats the convenience of digital and the cost is far less
when you can simply erase and reshoot...

JT
 >> Stay informed about: No P&S for a serious hobbyist? 

Canon SD 800IS.
Just bought one 3 weeks ago and I am ready to sell off all my other gear.
Greta little camera with a 28mm FOV on the wide side, optical stabilization,
and great picture quality.
You can find it under $300 now.


--
© Johnny Slothman
Slowest Contractor In The West
If you need it done 10 years from now, call Johnny
 >> Stay informed about: No P&S for a serious hobbyist?