Tags

, , , ,

I realize there may be some readers who want to improve their photography, but only want to use $100 point and shoot cameras.  My wife is in that category.  There may be a few tips here and there that will help these people.   But, anyone who is the least bit serious about quality photography will at least invest in a digital SLR camera (DSLR), which will give you options for setting aperture, shutter speed, ISO, white balance, etc..    It is very difficult to control the quality of your photography, if you can’t control the essential elements that go into making a photo.

However, even many of the point and shoot cameras today will give you the option of shooting in RAW mode… but many amateurs choose rather to shoot in JPEG, largely because the RAW format is so misunderstood.  So today, I will try to unwrap a little of the mystery surrounding file formats, and when and how each should be used.  The three most commonly used formats in photography are RAW, TIFF, and JPEG.    I use all three, but I only shoot in RAW mode.

The most difficult thing for people to grasp is that a RAW file is NOT an image file — it is the recipe (for lack of a better analogy) for making an image.   A digital camera sensor collects data about each pixel of light it receives (color, hue, brightness, etc) and stores it in the camera… the camera’s processor can then use this pixel by pixel data to create an image (usually JPEG).   However, JPEG is a lossy file format, meaning that pixel data is thrown away in order to create a smaller file.   The larger problem with JPEG is that editing the image in post-processing further degrades the image.  Each time we open and save a JPEG file we have further image degradation — not a result that those of us interested in image quality are happy with.

Most camera manufacturers supply RAW editors with their cameras (realizing that many of us can’t afford $500 for the full edition of Photoshop).   I use Canon’s RAW editor built into its Digital Photo Professional software with great results.   The beauty of a RAW editor is that you are simply changing the “ingredients” BEFORE they are all mixed together into an image.   I can change white balance, light, contrast, sharpness, hue, saturation, shadow intensity, light intensity, etc… prior to creating an image.  At any point, if I’m not happy with my adjustments I can undo them and go back to square one without any photo degradation… Why?   Because I am only dealing with a “database” of values — RAW data.   I’m not actually dealing with an image yet.   I’m just changing the recipe beforehand.   For this reason you should ALWAYS shoot in RAW mode, and NEVER delete your RAW file.

Now, once I’ve edited my RAW data and I’m ready to convert it to an image, what image format should I use?   Assuming that almost 100% of the time, there will be some post-process photo editing done — touch-ups in Photoshop, removing blemishes, cropping, color or clarification, etc. — then remembering the disadvantages mentioned above regarding editing lossy formats like JPEG, then obviously we don’t want our original image in JPEG.   This is where TIFF comes in.   It’s an image format, but not a lossy format.  It’s the highest quality image format available.   The file size is extremely large and unsuitable for emailing and the web because of this, but perfect for editing.   No pixels are ever thrown away, so no matter how many times you open, edit and save a TIFF file, you will never lose any pixel data or degrade the image.

However, we are now editing an image and not just RAW data, so any changes we make will change the actual image and not just the data behind it.   What this means is that if I open a TIFF file in a photo editor and sharpen it, enhance brightness and contrast, add color saturation, etc., then save it.   I can’t open that file tomorrow and go back to its original state.  Though no pixel data has been lost, the pixel data has forever been changed.   So for this reason, it’s a good idea to get into the habit of saving each new edited file as a new file (img_1a, img_1b, img_1c) so you can always go back to a previous state if you want to without having to start all over at square one by going back to the RAW editor and creating a new original TIFF file.    Only when you are 100% happy with your final result, should you save in JPEG format.   JPEGs should NEVER be edited.  If you want to edit a JPEG, you should go back to your last TIFF and edit it, and then save a new JPEG.   If you are going to upload JPEGs to labs for printing they should be saved at highest quality (usually 99%), if you are going to upload to the web, then 90% should be fine (you’ll want to resize as well, obviously)… thumbnails etc are usually fine at 75%-80%.

As you can guess… all this takes a HUGE amount of disk space.   Be prepared to purchase a LARGE dedicated hard drive or a DVD burner to store your images on.  Again, I use both.   You can get 1-TB hard drives for about $50 now.  You may also want to invest in a good image database software like iMatch … but that’s all for another post.

For more in-depth (and technical) discussion and analysis of the RAW format see WikiPedia or this excellent article.

Happy shooting!  And by all means, share your outstanding photos.

Advertisements