Tutorial Time: The Digital Darkroom

All photographic artists use a darkroom, even digital artists. Rather than enlargers, negatives and chemicals the digital artist uses a computer, files and a photo editing program.

As photography enthusiasts we hear the word “pixel” a lot, and we know more is better but how does having more pixels affect an image?

Computers use binary to record information, combinations of 1 and 0. A bit is the smallest and is either a 1 or a 0. A byte is an 8-bit sequence of 1s and 0s.

A bit is the smallest unit of digital information, example: 1

A byte is 8 bits, example: 1 0 0 1 1 0 1 0

A kilobite (KB) is 1,000 bytes.

A megabite (MB) is 1,000,000 bytes.

A gigabite (GB) is 1,000,000,000 bytes.

A terabyte (TB) is 1,000,000,000,000 bytes.

The size of an image is the number of bites it contains.

The quality of the image is determined by how many pixels the image has. Each pixel has a bit depth (remember a bit is the smallest unit of digi info). The more bits per pixel the more color detail can be displayed in each pixel.

1 bit per pixel: 2 values, black and white only.

8 bits per pixel: 256 tones for black and white pictures.

24 bits per pixel: 16,777,216 colors for color pictures.

Okay all this nerdy computer information leads to what I want to stress the most: The relationship between SIZE and RESOLUTION.

SIZE: The dimensions of the final print.

RESOULTION: The number of pixels per inch.

To check the size of your image open up your image file in Adobe Photoshop. Click on image and then image size. The pixel dimensions represent the resolution of the image and the document size (in inches) is the MAXIMUM size you should print the picture without compromising the quality of the image.

In this example the size of this image is 8.3 inches by 12.5 inches and would look best at this size or smaller.

I know we’ve all seen photographs hanging in coffee shops that have been blown up larger than they should have been and frankly, they look unprofessional. The document size of your image should be the most important guideline to having your picture printed for public viewing. *

TIP: *Always use a professional service to print images you plan on framing or mounting to display or sell.* If you have purchased a personal “photo” printer it should be primarily used for the printing of PROOFS for a portfolio or for reference. Do not purchase a “professional” photo printer, it will only cause you to want to throw it against a wall. The color is never accurate and the printer uses up a lot of ink if the nozzle gets clogged. When you have your prints professionally done remember: The glow from your computer screen enhances the color and vibrancy of your image and therefore the print may look darker and less vibrant than expected.

*Useful file type guide:

JPEG: Compresses photos to up to 1/20th of original size.

**TIFF: Universal format for high-quality photos.  (BEST QUALITY)

PSD: Photoshop document.

RAW (NEF for Nikon): Most representative of the exposure on the camera sensor.

PNG: Good for web-based photos.

More tutorials to come, ask if there’s anything you’d like me to write about.*