Bob Williams wrote:


Wolf wrote:
Bob Williams wrote:

Most monitors can be set at any of several screen resolutions
(sizes), anywhere from 800x600 pixels to 1400x1050 pixels or even
greater.
Many photo editors can resize images to any desired size.
When sending pictures to this group, the optimum size is the largest
that can be viewed by the majority of viewers without scrolling.


Not true -- see below.

By "OPTIMUM SIZE" I did not mean highest image quality.

I interpret that to mean file size. If that's what you have in mind, we
agree.

I suggest about 200KB, which is small enough for dial up users to get in
a reasonable time, and large enough to allow for large but not overly
large images, thus permitting for good to very good image quality. At
the usual dial-up rate of 56Kbits/second, a 200KB image will download in
about 30 to 45 seconds, allowing for repeated packets. **

Assuming that optimum file size is somewhere around 200KB, then JPEGs of
quite large images will easily fit into that optimum size - see the
images I posted, half of which are which are 300KB or less. ***

The fact is that image size has a rather complicated relationship to
file size. That's why I suggested that we agree on an acceptable file size.

** Since getting broadband, I've noticed that demand on the server has
more effect on the actual download time than transmission speed. I've
waited 10 seconds and longer before a download even started when the
host server is busy. Also, the download may pause for seconds at a time.
On dial up, I rarely noticed this - the slow transmission speed masked
these effects of server overload.

*** Keep in mind that the JPEG file size is determined by the amount of
detail in the image. Many of the closeup images posted here have large
areas of the same colour, so that they will compress very well indeed
without noticeable loss of quality.

The picture may be magnificent but very few people on this NG will dare
open it, especially folks with telephone modems. And those few who did
open it would be treated to such a huge image that they could not view
it in its entirety without scrolling widthwise and heightwise, big time!
With images of this size, the amount viewable at one time is typically
so small that it is almost impossible to discern and appreciate the
composition of the image.

Perfect examples of this are your posts of the Crocus and the Begonia.
Both are very nice pictures but you could not tell it by looking at the
large, high resolution images you posted.
[...]

Yes, you're quite right. I will repost a series of the same picture at
different image sizes. Let the group decide which one(s) work best.

[...]

BTW, you can set pretty well any newsreader to automatically use an
external program to view pictures. If this is done, scrolling isn't
necessary, since the external viewer can display to fit the screen. That
external program stays open once invoked, and it takes an extra couple
of clicks to switch between reader and viewer. IMO that's a small price
to pay.

--


Wolf

"Don't believe everything you think." (Maxine)