Raw Deal?

[Gord]

Hi My name is Gord. I am very new to the digital world of cameras. I have owned SLR's for over 22 years.
Now I am so fascinated with the new digital era. I have now decided on the purchase of a Cannon G1. Scouring the internet and lastly finding this page full of resources has been wonderful. I am comsumed with learning this new format of photography. One thing I want to understand is Raw. I know they are big files and the photo's are awesome to look at on the computer. I also understand they are not compressed files but are they still a JPG file or does it have an extension called .RAW. Another question I would like to ask is, after you take a RAW photo I understand you can download into your computer and tweek a variety of things like the color balance and so on. Why can't you do that with a compressed JPG photo once it has been down loaded. That's all the questions I have for now. If anyone can steer me in the right direction that would be appreciated. Thanks Gord

[gbjune]

gord wrote:
Hi My name is Gord. I am very new to the digital world of cameras. I have owned SLR's for over 22 years.
Now I am so fascinated with the new digital era. I have now decided on the purchase of a Cannon G1. Scouring the internet and lastly finding this page full of resources has been wonderful. I am comsumed with learning this new format of photography. One thing I want to understand is Raw. I know they are big files and the photo's are awesome to look at on the computer. I also understand they are not compressed files but are they still a JPG file or does it have an extension called .RAW. Another question I would like to ask is, after you take a RAW photo I understand you can download into your computer and tweek a variety of things like the color balance and so on. Why can't you do that with a compressed JPG photo once it has been down loaded. That's all the questions I have for now. If anyone can steer me in the right direction that would be appreciated. Thanks Gord


The files are not JPEG, and since there is not a standard in place for these files, you need software specific to your camera to import these pictures.

If you search either here or at http://www.dpreview.com in the forums there, there have been plenty of discussions about RAW in different forms.

A quick search here should give you what you need to know.

=Geir

[n9505605]

Hi Gord,

Raw is consider to be a better format than JPG. What most digital camera use is either JPG or TIFF. But Canon has it own format of TIFF, which is call RAW. The file size between the 2 is that Raw is about 1/3 the size of TIFF.

Now, Tiff, BMP and RAW is consider lossless. What they mean by that is they preserve 100% of the information about every pixel in the original image. So, no matter what the original image contains, the file size is effectively the same. Of course, if your change the resolution, the file size will change also.

WIth JPG, this one is abit lossy. What I mean by that is JPG compressed the file to save space. Most digital camera allows you to change the compression ratio such as (Superfine, fine and basic or best etc). Remember, the more the file being compressed, the more information you will lose. you can even try this yourself. Make a copy of a pics, and save it over and over again using JPG format. after doing this 10, 20 times, compare this with the original and you should see the difference.

Also, if the pixel contains nothing or the colour of the pixel is white, it uses no space I think... and JPG do not store all colour information compare to TIFF and BMP.

However, you can preserve your original image by converting it into TIFF or BMP after you have downloaded the file into your PC.

Regards,
Boshala