Why not use the largest size and highest compression?

Question

I just bought a Canon S5 IS. I've owned other cameras in the past but always just used the auto setting for everything. This time I'm reading a little bit to better understand.

I don't take a lot of pictures even when I'm on vacation. I bought a 2 gig extreme III card to go with the camera. For these reasons being able to take a bunch of pictures is not as important as the quality of the pictures.

I noticed when I take pictures the size is very big when I pull it up on my computer. I read a little and it seems at though the best quality of pictures are when you set the camera to the most pixels and the highest compression. Other than this limiting the number of pictures you take, are there any other drawbacks to this?

Also, lets say the largest picture I would ever want to get developed is 5X7. When the picture size is reduced using my own software or a developers, does reducing the size actually make the picture look better, worse, or the same?

Answer 1

The best quality, when saving the pictures in "jpg" format, is the maximum number of pixels and least amount of compression.  "RAW" format is the highest quality way to save photos, but that format takes up a _HUGE_ amount of storage, and most commercial photo printers and home computer software can't deal with RAW files.

Since you said the quality of the pictures you take is more important than the quantity, set your camera for the max number of pixels and least "jpg" compression.  You can always use common software to make a copy with reduced file size for sending by email.

If you photo is going to be sent by email and/or used on a Web page, and you figure it's not going to be printed but just viewed on a computer only, save the file as roughly 640 pixels by 420 pixels.  Most computer screens can't display photos any better than that.  Sure, the recipient could want to magnify the details that only a larger file could supply - but you'll probably be told if that's the case ahead of time, and  most people don't want to wait for large file to download in my experience.

When making prints,the "point of no more return" is about 300 pixels per inch unless your eyes are really sharp.  Myself, I can't see any increase in sharpness between prints made at 150 and 300 pixels per inch without a magnifying glass - and most people realistically don't look at photos under magnification.  At 300 pixels per inch, a 5" by 7" print would need about 300*(5" * 7") or about 10500.  Given that most cameras don't take 5 by 7 format photos, figure about 15000 pixels for cropping.  (The need for editing/cropping is probably the biggest reason for saving the pictures at maximum resolution, since cropping degrades photo quality so quickly.) The end result file size will depend on the  amount of compression, but should be well under about 250 kilobytes.

Saving your photos at maximum resolution will make sense some day when you'll want to 8" by 10" or larger prints of some of your best work.

Doing a lot of repeated photo editing (change something about a picture and save it, change that file and save it, etc.) with "jpg" files will cause the picture to look a little bit worse with each change.  Make all changes  to a photo in one work session, and save the file just once.  Keep a copy of the original in case you change your mind later and want other changes....

Answer 2

Largest size, smallest compression will give the best quality. The large size is caused by most software opening Jpeg files at 72ppi which is screen format. Increase the resolution to 300ppi and the image will be smaller on the screen.

Memory cards are so cheap you really should always shoot at the best resolution and quality you can, good prints will always require the highest number of pixels available, when you see one of your better pictures printed at A3 or larger you'll be really glad you kept your options open by saving at maximum quality and size.

Chris

Answer 3

You NEVER know when you may take a shot that is so amazing, you will want to make it much bigger than you originally thought.  If you have not used the maximum resolution it is capable of shooting, you will not be able to make the larger print ... and of course you have wasted your money on the high quality camera, just to use it at resolutions found on cheaper cameras.

Just shoot at your cameras highest resolution ... then if you want to send copies in email or post them to the sites on the Internet, just re-size those images and save them as a different file name, so you don't overwrite the original.

600 x 400 @ 72 DPI is the typical size image posted or sent via email