Should set 6 MP digicam to 3 or 4 MP?

My digicam is rated at 6 MP (0.5 inch, square pixel, 6.37 million).

It can record still pictures as JPEGS using one of three settings:
Fine, Normal or Economy.

-----

QUESTION ONE
Do these three settings represent different amounts of jpeg
compression?

Or would the the camera ignore some pixels from the CCD in the lower
quality modes and then make its jpegs from the remaining pixels?

-----

QUESTION TWO
I can "specify image size" by using a different number of pixels:
6M 2816 x 2112 A3 print
4M 2304 x 1728 A4 print
2M 1600 x 1200 3.5 inch x 5 inch print
etc

I am not likely to make prints larger than A4. So should I set the
camera to "4 MegapPixels"?

Or will there be a loss of quality from things like the
interpolation/extrapolation of the original 6M pixels to derive the
content of the new pixels?

-----

QUESTION THREE
I could save a jepg in FINE mode onto my PC (approx 2 or 3 MB file
size) and then, if necessary, later compress it further to something
like 600 KB for use on the Web. This is convenient.

Would I get *noticeably* less quality doing it that way compared to
recording the picture at Economy mode in the first place in the
camera? This is not so convenient but would give me a jpeg file of
approx 600 KB straight away.

------

Susan P wrote:
Would I get *noticeably* less quality doing it that way compared to
recording the picture at Economy mode in the first place in the
camera? This is not so convenient but would give me a jpeg file of
approx 600 KB straight away.

This isn't really the proper forum for these questions, but I'll answer
with a bit of advice: You should always take pictures at the highest
resolution and lowest compression that your memory card will allow.
This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.

Jim Leonard wrote:

This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.

Indeed. In 5 years, the question which people will be asking on the
forum will be: "Should I get an 18-megapixel or 20-megapixel camera ?
Cann't choose".

On Mon, 21 Aug 2006 15:33:04 +0100, Susan P wrote:

My digicam is rated at 6 MP (0.5 inch, square pixel, 6.37 million).

It can record still pictures as JPEGS using one of three settings:
Fine, Normal or Economy.

-----

QUESTION ONE
Do these three settings represent different amounts of jpeg
compression?

Or would the the camera ignore some pixels from the CCD in the lower
quality modes and then make its jpegs from the remaining pixels?
Yes

-----

QUESTION TWO
I can "specify image size" by using a different number of pixels:
6M 2816 x 2112 A3 print
4M 2304 x 1728 A4 print
2M 1600 x 1200 3.5 inch x 5 inch print
etc

I am not likely to make prints larger than A4. So should I set the
camera to "4 MegapPixels"?

Or will there be a loss of quality from things like the
interpolation/extrapolation of the original 6M pixels to derive the
content of the new pixels?
I wouldn't. You might find that you are pleased with a picture that you
taken in a lesser mode and that you cannot make a print to the quality
that would please you. Better to take at maximum quality - it is easier to
lose it than to put back that which is not there.
-----

QUESTION THREE
I could save a jepg in FINE mode onto my PC (approx 2 or 3 MB file size)
and then, if necessary, later compress it further to something like 600
KB for use on the Web. This is convenient.

Would I get *noticeably* less quality doing it that way compared to
recording the picture at Economy mode in the first place in the camera?
This is not so convenient but would give me a jpeg file of approx 600 KB
straight away.
Do it the way you suggested.




--
Neil
Delete l to reply

minnesotti wrote:
Jim Leonard wrote:

This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.

Indeed. In 5 years, the question which people will be asking on the
forum will be: "Should I get an 18-megapixel or 20-megapixel camera ?
Cann't choose".


Hi...

I'll "third" that, if there even is such a thing

Who knows what the future will bring; and who knows
what your descendants will wish to do with pics taken
today. Leave for them the best you can

Take care.

Ken

"Jim Leonard" wrote in message
ups.com...
Susan P wrote:
Would I get *noticeably* less quality doing it that way compared to
recording the picture at Economy mode in the first place in the
camera? This is not so convenient but would give me a jpeg file of
approx 600 KB straight away.

This isn't really the proper forum for these questions, but I'll answer
with a bit of advice: You should always take pictures at the highest
resolution and lowest compression that your memory card will allow.
This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.


Absolutely correct. Always use the highest resolution and lowest
compression for best image quality.

Some cameras default to a "middle-of-the-road" resolution and/or
compression. That seems foolish, because one buys a higher-megapixel camera
for its presumed better quality images, so why use less than you paid for?

The only reasons I can think of to use more economical settings a

1: If you're running out of room on your memory card and you absolutely must
stretch out the remaining number of shots.

2: If you are shooting for the sole purpose of emailing or posting on a web
site--to be viewed on a monitor only

3: If you are taking photos that you never intend to print, perhaps home
inventory shots that you want to store on CD and lock away in a safe deposit
box. What I call "utility photos." Where maximum resolution and size are
not as important as small file size is.

I would suggest that the OP set his camera to default to biggest file size
(lowest compression) to ensure that he gets the maximum quality photos.

I wonder how many people have bought digicams that defaulted to less than
best image quality, and went on shooting with them for long time, never
realizing that they were not getting all the quality they had paid for?
I'll bet the number of such users is significant.

"Susan P" wrote in message
...
My digicam is rated at 6 MP (0.5 inch, square pixel, 6.37 million).

It can record still pictures as JPEGS using one of three settings:
Fine, Normal or Economy.

-----



Generally speaking, you should always shoot at highest resolution and lowest
compression, and if you require smaller size you can adjust in your editing
software.

If you take the photo at reduced settings, and you later decide you want a
high-quality print, you will be unable to improve the shot. Think of your
original file--as it comes out of your camera--as a digital equivalent of a
negative. You should always keep these unedited image files on disk for
permanent reference. Who knows, in the future we may have much improved
editing software, or you may decide that your editing skills have improved
to the point that you want to re-edit some of your older shots and try to
get a better result. In order to do that, you need two things:

1: The best possible image from your camera--i.e., highest megapixel and
lowest compression

2: The original UNEDITED file, just as it came out of your camera--before
you tweaked it in your editing software. Remember, when you edit your file,
you are throwing away pixels (as when you crop) and when you change things
like color saturation you are adding pixels. Always keep the original file,
and you can always go back to it and redo your tweaking.

I make it a habit to burn my unedited files to disk prior to doing any type
of editing, to insure that I don't overwrite them in error. Any resizing,
changing of color depth or downgrading of resolution can then be done in my
editing software. If I make a mistake, I always have my original unedited
files to go back to.

The only changes I ever make to my unedited files is to rename them to
describe what their subjects are. Then they go right to the archive disks.

"minnesotti" wrote in message
oups.com...

Jim Leonard wrote:

This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.

Indeed. In 5 years, the question which people will be asking on the
forum will be: "Should I get an 18-megapixel or 20-megapixel camera ?
Cann't choose".


Five years? More like 5 months! :-)

Susan P wrote:

QUESTION TWO
I can "specify image size" by using a different number of pixels:
6M 2816 x 2112 A3 print
4M 2304 x 1728 A4 print
2M 1600 x 1200 3.5 inch x 5 inch print
etc

I am not likely to make prints larger than A4. So should I set the
camera to "4 MegapPixels"?

Personally I would say: 6M

You can always scale 6M to 2M with software that gives you more control
then you camera. Also, if you make a picture that you want to print @ A3,
you have it.

--
John MexIT: http://johnbokma.com/mexit/
personal page: http://johnbokma.com/
Experienced programmer available: http://castleamber.com/
Happy Customers: http://castleamber.com/testimonials.html

"minnesotti" wrote:


Jim Leonard wrote:

This is because, 20 years from now, speed and space will be very cheap,
and you'll be happy you have the highest quality pictures.

Indeed. In 5 years, the question which people will be asking on the
forum will be: "Should I get an 18-megapixel or 20-megapixel camera ?
Cann't choose".

Or: should I get the 0.3 or 0.5 GP camera with 1 TB holographic storage.

--
John MexIT: http://johnbokma.com/mexit/
personal page: http://johnbokma.com/
Experienced programmer available: http://castleamber.com/
Happy Customers: http://castleamber.com/testimonials.html