You should record images at full size (2048x1536). If you know you
are going to use these shots for on-screen viewing at e.g. 800x600,
and if you are concerned with storage space in the camera, you can
use the most compressed setting, and you won't see any difference
once you resample the image to the smaller size and add a little
unsharp mask. The reason is that any visible JPEG artifacts will
be averaged out when you resample to reduce the dimensions.
If you are going to print, or enlarge, the story changes. For this
discussion, I will assume (always a dangerous thing to do) that
your print service has a max resolution of 300 ppi. When you give
him your 2048x1365 (you remembered to crop it, right?) file to be
printed at 6x4, the file will have 341 ppi. You print service will
have to throw out 41 ppi. He will tactfully do this and you'll be
none the wiser. Since you are averaging away pixels, you can
afford to have some minor JPEG artifacts which will get smoothed
away in the averaging process. Therefore for a 4x6 print, you can
shoot Large Normal (medium compression setting) and you won't see
any JPEG artifacts.
Now what happens at 5x7? You now give your printer a 2048x1463
file (again...you remembered to crop?) and he has only 292 ppi. He
needs every last pixel and then some! He will actually stretch the
pixels a wee bit to cover the picture. Since you are magnifying
pixels, you definitely don't want any JPEG artifacts. For this
case, shoot Large Superfine (least compression). If you become
obsessed, you can resample your file to 2100x1500 so that your
printer won't have to stretch your pixels...you've already done it!
for 8x10 it's even worse. The biggest file you can deliver is
1920x1536. This is only 192 ppi. At this size, each pixel needs
to be magnified by over 50% in both height and width in order to
print at 300 ppi…the resolution of the printer. Now, you
definitely do not want any JPEG artifacts or other noise present.
In this case, probably want to turn the in-camera sharpening to –1
so that you don’t nave noticeable magnified sharpening artifacts in
the print.
I usually shoot in Large Superfine with sharpening turned to –1. I
can capture
80 shots on a 128 MB card. This is more than I
generally take in a day. If I needed more space, I wouldn’t
hesitate to knock the compression setting down to “Normal”.
I do occasionally use the 1024x768 or 640x480 setting for
high-speed continuous mode. I like that you can capture more than
30 images at better than 3/sec in the low resolution mode. Other
than that I don’t see any benefits from using the low res modes.
I hope this helps.
I recently purchased the Canon S30 camera, and I am a newbie to
digital photography. Sorry for the stupid question, haven't had
time to peruse the board for this info but here goes.
Could someone please help me with the "optimal" settings for
resolution and compression assuming I want to print some of the
pictures? For 4x6, 5x7 and 8x10 what settings do you recommend? I
am trying to find a good balance between getting prints that rival
35MM film prints, but also managing space on the memory card. I
have a 16MB and 128MB memory card.
Also, for pictures that I never intend to print, what do you
recommend for resolution and compression settings?
Thank you.
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http://www.pbase.com/mango