Re: Mega Pixel Myth

David J Taylor offered these thoughts for the group's
consideration of the matter at hand:

When I speak of the several most common image damage, I mean
JPEG overcompression artefacts, not resizing interpolation. I
find that the latter mainly causes aliasing/jaggies visible
when zooming in or when printing, of course. The solution to
the print problem is obvious: save to a larger pixel size.
But, as I've said several times in this thread, almost always
I am simply watching a slide show or looking at wallpaper on
a Samsung 213T 21" LCD monitor. If I open the large images in
PSP 9, they display as well as can be expected but when
Windows resizes a 1600 x 1200 image, or even a 4 MP image
down to 1280 x 960, it looks like total crap to me.

Yes, that was one reason I wrote by own display program, which
does proper interpolation. I'm not sure how well the Windows
"Picture and FAX Viewer" program works with different sized
images.

I stopped viewing a PC as a hobbyist toy and started looking at
it as a tool to do useful work almost literally one day in 1995.
I stopped all my programming efforts and concentrated on getting
the beastie to do what I wanted it to, not the other way around.
My congrats, though, on having the technical know-how to write
such a displayer. I never use the Picture and FAX Viewer so I
have no idea how it does it.
[]
Yet, these two people thought they were looking at film
enlargments. No, I'm not bragging. They were holding these
prints at about the distance you hold a newspaper you're
reading, and the aliasing and occasional other image damage
just isn't visible that far away.

Yes, this is exactly how JPEG was designed - so that whe
viewed at "normal" distances the artefacts disappeared, and my
personal opinion is that it does that very well.

Yes, it does, but after stumbling around for about 15 years first
scanning and now digital and scanning, I only RARELY go over
JPEG=10 on the 1-100 scale. I have to add that because some
programs view it as a percentage, which it clearly is not, but
people are taught that anything on a scale of 100 must be a
percentage. I also learned the hardware a long time ago to re-
open just-saved JPEGs and check for damage; if I find some, which
I do about 1-2% of the time, I'll reduce the compression some
more and play with a couple alternate settings for Chroma
subsampling. My goal is a good compromise between image quality
and file size, but at today's cost/gig, quality is more important
than size.
[]
I know how to do that, naturally, but almost all the people I
know that print 4 x 6's at Meijer just take their memory card
to the kiosk, select the images they want to print, and let
'er rip. Most have no idea what post-processing is all about
but they're interested in today's version of snapshots, not
what "real" photographers do. e.g., when I looked at my
daughter's pics from a weekender to the Michigan Sand dunes,
about half could have been made infinitely better with just a
couple minutes in PSP to crop and fix the obvious stuff. But,
she's satisfied with them the way they are, it's her
business, not mine.

I have friend who's just retired and getting into digital
photography. Fortunately, he does now realise that you can do
a lot more with post-processing. Nevertheless, my own aim is
to keep post-processing to a minimum, and hence, like with
slide photography, to get it right in the camera.

Clearly, doing it right the first time always beats tweaking
later. But, it is awfully rare for me not to at least want to
crop for better composure, adjust the WB, maybe RGB/HSL,
brightness/contrast up or down, sharpen, and a few other basics.
I could easily script that but the tweaks are never the same, and
in extreme cases, usually in museums, it is a major challenge.
But, again, more and more people seem to want to short cut their
way to vastly improved print quality without learning any of the
raster graphics basics, the fundamentals of printing, and doing a
little old fashioned work.
[]
All that said, if I were an artistic photographer, I would
hardly be going for quantity, so I would set up a tripod and
do it the right way. But, I am a documentary collector. Lest
you think I have no quality standards at all, that isn't the
case. Life is one big compromise and more often than not, we
wind up with a Hobson's Choice. But, since the person I have
to satisfy is me, and not a judge in a contest, so what?

Completely agree - if I were a professional photographer it
would be different, but like you, I have only myself (and
perhaps my wife) to judge the pictures. I do have a desire to
understand the science behind the choices I make, though, as I
expect you do as well.

Needless to say, David, when I post to the car picture NGs, I get
savaged for less-than-optimum image quality but some people
apparently view this as some sort of contest. I view it as a
hobby. If it becomes work or becomes a big enough pain in the
butt, well, I just won't post. And, I've posted precious little
since last summer.

BTW, I'm quite happy to see that, for a change, some perspective
on the practical side of all of this is prevailing in this thread
and people are allowing for the outlandish notion that there may
really be alternative ideas! <grin>


--
HP, aka Jerry
.

Relevant Pages

  • Re: Camera recommendations?
    ... > photography many years ago but that lapsed, ... I'm really into image quality ... Because D-SLRs generally use bigger CCDs than compacts, ... picture which is 160Mb when stored. ...
    (uk.rec.photo.misc)
  • Re: Is Contrast Ratio THE spec that makes the biggest difference?
    ... picture from spec sheets among various sets and manufacturers (LCD set size ... not wanting to spend another $500 just to eke out a little more in quality. ... comparison for picture quality. ... Resolution is source based - the immediate perception, ...
    (alt.tv.tech.hdtv)
  • Re: Text overlay on image then Save to JPEG with reasonable DPI for Online printshop
    ... text and also including the image of the guy sitting at the desk. ... page the entire picture is an original bitmap (or jpeg or whatever) that has ... been saved as a using the highest quality jpeg compression ratio (it appears ...
    (comp.lang.basic.visual.misc)
  • Re: FPS video rate question
    ... The intermediate speeds shown offer a trade off between picture quality ... the video would be microscopic in size on my home computer and if I ... For a given sensor array and data transfer setup, which is what a camera basically is, the picture quality has to go down as the frame rate goes up. ...
    (rec.video.desktop)
  • Re: Question re jpeg compression
    ... I notice in the options settings of my editing software there is the ability to set the default compression of jpeg files. ... The help says the higher the setting the higher the quality and the larger the file. ... I am thinking of converting all images to png immediately after importing from the camera, and keeping them as such, unless I really need to change it for something like emailing or publishing to a web album. ... If anyone has any thoughts as to why converting and storing in png format might not be such a bright idea I would appreciate your comments. ...
    (rec.photo.digital)