Difference between Super Fine and Fine

[wenzej]

I know what this does; Super fine is less compression then Fine and that Super fine is better because it looses less picture information. However it takes up twice the space.
I want to see if it makes any difference in the picture, so I thought I would shoot the same picture in Super Fine and Fine and compare them. I expect them to be very close, but I have no idea what to look for. Should I look for loss of fine detail or color shifts or what?
Also does it take longer to compress the picture more and save it to the card or does it take longer to save the larger file? What I wonder is would it cause a delay when taking pictures quickly?

[jyrgen]

1. You could put them on layers in your photo editing software and use a layer blending mode that shows the difference between the two layers. I don't know which mode, but there certainly is one. It might be helpful or at least interesting

2. I'm sure it takes longer to save the larger file. The Digic processor that does the compression among other things is pretty fast. You can verify this by thinking of or looking at the continuous shooting mode - you are limited rather by the speed the images are saved from the buffer to CF than by processing speed. Use the smallest format and worst quality jpeg and you can take lot more continuous pics, although they need more processing.

[John from PA]

In general shoot in the highest possible resolution you can get. Then later if you get that exceptional shot that you need to crop you might be able to do so without any major ramifications.

Also, don't repeatedly save an image as you work with it in software. I think a lot of people do this (habit from things like MS Word or Excel) but each time you do a "Save" the compression goes up and the image quality goes down. At a recent digital photograpy school I attended the instructor took a beautiful picture of one of the state quarters and then saved it 6 times. After the 6th save you couldn't teel it was a quarter.

[dtrayers]

Here is a comparison of the Superfine vs. Fine modes for the G3:

http://www.dpreview.com/reviews/canong3/page12.asp

You can click on the images to download the full size versions and compare them for yourself.

[Shaner (Ut)]

Question for John

When ya say don't repeatably save it, are you refering to saving while you're in the process of working on it without closing, or are you talking about opening the file, work on it, save it and close it, then repeat?

The small town I live in is famous for power bumps. There has been many times I have been in the middle of editing a pic and the power will go out so I started to save my work as I edited the photo.
I will make several adjustments and then save and keep editing but never close out the image (unless the power went out) until I'm done.

[dtrayers]

What John means is saving it in a lossy format like JPG.

Every time you save, the computer has to compress the picture, and it throws away some information. Do that too many times and you'll begin to see the degradation.

However, I think that if you have some kind of background save turned on, it's just saving and overwriting images, so you won't begin degrading until you re-open a saved image.

If you do need to make frequent saves, make sure it's in a non-lossy format, like a TIFF or, if you are using Photoshop, in it's native PSD format.

[hypokondriak]

The default windows jpeg viewing software that comes with windows is notorious for losing quality of shots. I used to rotate my pics with this - then I started watching file sizes.

Personally, I would only shoot SuperFine if I was shooting in that mode - that way you always have the highest quality pic for your archives... my anal .02 tho.