Where are the BEST Point and Shoot Photos ?

On Thu, 22 Nov 2007 23:57:16 +0000 (UTC), (Dave
Martindale) wrote in :

John Navas writes:

Most monitors aren't that good, more like 1/72 inch.

It doesn't matter what "most monitors" do, he provided actual numbers
for his!

It does for most other participants here. Don't you think they count?

It actually maxes out below 200 PPI.

No, it doesn't. The eye's resolution limit is about 60 cycles/degree,
and it takes *at least* 2 pixels to resolve a cycle. To achieve this at
a distance of 21 inches, you need at least 327 pixels/inch. The
calculation is

1 / (21 * tan(1/60 / 2))

If you disagree, where (exactly) do you disagree?

With your supported claim.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

On Fri, 23 Nov 2007 00:05:32 +0000 (UTC), (Dave
Martindale) wrote in :

John Navas writes:

There's a substantial flaw on that page!

The eye acuity page it refers to
http://www.scss.com.au/family/andrew/camera/resolution/#acuity gives
figures of 30 seconds of arc in good conditions, 1 minute of arc in
"ordinary" conditions, as the minimum separation between black lines on
a white background. That's one full cycle of the test pattern.

When converting from cycles to pixels, you have to consider how many
pixels it takes to create one black/white cycle. It takes 2 pixels as
an absolute minimum, but when you consider the effect of antialiasing
filters in real cameras you really need 2.5-3 pixels per cycle to
recreate the original pattern without aliasing artifacts at decent
contrast.

Citation? Or just your word on it?

Um, what would you like a citation for?
[SNIP hand waving]

I'm forced to conclude you have no supporting citations.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

In article , John Navas
wrote:

also, luminous landscape's d30 versus film comparison had different
fields of view in the two images, which gives the camera with the
cropped field of view (the d30) a huge advantage. ...

Not true, as the article makes clear.

ok, i did miss the part where he says he changed the zoom to match,
however, the film image has a noticably larger field of view than the
d30, so he didn't do a very good job of it.

he also says that the provia image is slightly taller because it has a
different aspect ratio as the d30. canon's specs say the d30 sensor is
22.7 x 15.1mm, which is a ratio of 1.5033. thus, if the film had the
same aspect ratio as the d30, it would be 23.95mm instead of 24mm.
that's less than half a percent difference and hardly noticable.

http://www.canon.com/camera-museum/c...-/2000_eos-d30.
html?lang=us&categ=crn&page=1995-&p=2

Dave Martindale wrote:
"David J Taylor"
writes:
So how is it that images on my 13 x 10.5 inch display, with all of
1.3MP, appear perfectly sharp when viewed at 21 inches? Something
to do with the pixels being sharp?

Your monitor has a pixel pitch of about 1/100 inch. Viewed from 21
inches away, each pixel subtends about 1.6 arcmin. The finest cyclic
pattern it can display is about 18 cycles per degree. Your eye's peak
sensitivity is somewhere around 10 cycles/degree, so an image that
resolves up to 18 cycles/degree is "pretty good".

On the other hand, your resolution limit is about 60 cycles/degree, so
if you gradually increased the resolution of your display from 100
PPI,
you would see some improvement in the image quality until you reached
somewhere above 300 PPI. And that's at 21 inches - up close, even
more
PPI would give a visible difference.

Still, the quality of the image at 10 cycles/degree and below is a lot
more important than what happens in the 10-60 cycles/degree range.

Dave

Dave,

Thanks for that. I suspect that images described as "crisp" or whatever,
have a relatively higher content at 10 cycles/degree.

It's the difference between an MTF with a long tail (e.g. film, older lens
design) compared to an MTF which is higher up to a certain spatial
frequency and then a sharper cut-off (digital, anti-alias filter, modern
lens design) together with the different noise spectrum and transfer
linearity which characterises the "digital" versus the "film" image.

Cheers,
David

On 11/22/07 2:34 PM, in article , "Peter Irwin"
wrote:

John Navas wrote:
On Thu, 22 Nov 2007 19:57:50 +0000 (UTC), Peter Irwin
wrote in :

John Navas wrote:

1.5 ? diagonal, which comes from authorities I've cited,
is actually conservative.

I certainly look at my 8x10 prints from about
a one foot distance. ...

Then you need to adjust accordingly for yourself,
and not presume to judge for everyone else.

Um, You are the one who is presuming to judge for everyone else.

I'm pointing out that my personal experience is that people
of my acquaintance including myself do look closely at largish
prints.

Peter.
You are dealing with a pompous asshole, just in case you didn't know.

Just ask the folks at alt.cellular.cingular...

On Fri, 23 Nov 2007 12:21:55 -0600, George Kerby
wrote in
:

You are dealing with a pompous asshole, just in case you didn't know.

You've described yourself quite well.

Just ask the folks at alt.cellular.cingular...

Just ask the trolls and common bullies at alt.cellular.cingular...

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

John Navas writes:

Um, what would you like a citation for?
[SNIP hand waving]

I'm forced to conclude you have no supporting citations.

I provided references to all of the information needed to perform the
calculation yourself, so you could duplicate my numbers, or identify
where your calculation differs from mine. That's generally considered
much more reliable than a pointer to someone somewhere who came up with
the same numbers as I did.

Web pages are of limited use as citations, because they often have
errors (as does the one you pointed to). The same is true of textbooks
to a lesser extent (since textbooks tend to get reviewed by someone).

If you think there's a flaw in my numbers, point out the error
yourself! If you can't write down and defend your own calculations,
you're merely parroting someone else's web page.

Dave

wrote:
Ok, i have seen some incredible dSLR photos on the
web.

I have yet to see a mind-blowing point and shoot photo
gallery. Does anyone have a great link?

Mind you, i have pretty much decided to order the Canon 40d
tomorrow.

But if i wake up tomorrow, and find something incredible that
was done with a P&S, you can bet that i will re-consider.....


DT

I was expecting some links to some excellent photos taken with p&s
digital camera as a reply to this post. Instead many replies are just
rhetorical comparison without any practical results shown. The absence
of examples just makes the comparisons more abstract. And finally, sadly
but not surprisingly in this newsgroup, still many others are just
childish gibberish. Compared with the number of replies, the example
URLs given are tiny in number. Don't even get me started on some other
threads --- most of which have the theme "mine is better than yours" and
it goes on an on an ooonnn... What has this newgroup come to?

RealityByter writes:

Your resolution doesn't mean one damn thing if there's nothing in it worth
conveying. If there's something in your data worth conveying than people will
want to see it even at 640x480.

This is the argument that everyone should use an Instamatic, or a
Mavica, or whatever is the worst camera available at the time. For
some subjects that's good enough. But most people will prefer a sharp
photo of a subject compared to a blurry washed-out image of the same
subject.

There's also a long tradition in photography of caring about resolution
and dynamic range and other things that affect image quality. This
discussion is for that side of photography. If you don't happen to care
about that side of photography, why not butt out of such discussions?
Nobody cares what you think should and should not be called
photography.

My own photography is for me. I don't have the slightest interest in
whether you win contests with your photography, because I'll never see
your photographs, and I have no interest in "conveying" anything to you
either. I am interested in talking about photographic quality with
others who have similar interests, but no interest in the "what is art?"
discussion.

Dave

On Fri, 23 Nov 2007 20:41:14 +0000 (UTC), (Dave
Martindale) wrote in :

John Navas writes:

Um, what would you like a citation for?
[SNIP hand waving]

I'm forced to conclude you have no supporting citations.

I provided references to all of the information needed to perform the
calculation yourself, so you could duplicate my numbers, or identify
where your calculation differs from mine. That's generally considered
much more reliable than a pointer to someone somewhere who came up with
the same numbers as I did.

Web pages are of limited use as citations, because they often have
errors (as does the one you pointed to). The same is true of textbooks
to a lesser extent (since textbooks tend to get reviewed by someone).

If you think there's a flaw in my numbers, point out the error
yourself! If you can't write down and defend your own calculations,
you're merely parroting someone else's web page.

It's your job to support your contentions, not mine, and you've yet to
do so. I'm thus forced to conclude you have no supporting evidence.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)