You may hear these terms when discussing your project with us here at Centric Photo. This is a quick guide to some terms that are Centric-specific as well as standard industry terms.
This is the machine that does most of the grunt work for Centric Photo. The machine must be constantly maintained to ensure proper balance of color and density as well as consistency throughout subsequent jobs. This printer can output sizes from wallets (2-up) to 12×18 on either matte or glossy paper.
(Pronounced gee-CLAY or shee-CLAY) is a term that has come to describe the process as well as the product produced from high quality inkjet printing. It can also mean fine photo print. In the artist community, giclees are replicas of original work printed on a variety of substrates. They are typically associated with fine papers such as Watercolor or Canvas. We print ours using the Epson 9800 Pro series printers with a maximum width of 44″
Usually referred to as a material that our inkjet printers can print on. For best results, the substrates must be treated specifically for the use of Pigmented Solvent-Based inks.
x-Base (4-base, 16-base, etc)
Nortisu 2901 term for the size of a scan produced from film. Origins of the terminology are a little unclear, but technicians began to refer to the scans with these names because of the software running the 2901. Probably linked to the powers of 2, the most apparent correlation is with file size. 4-base Tiff files (uncompressed) run approximately 4.5 Mb, and 16-base (the next highest scan) is 4 times as large at about 18.1 Mb. If you hear us using these terms, just know that we are talking about a Noritsu film scan choice on our machine.
This is a difficult concept. TIFF files are generally uncompressed whereas JPG or JPEG files are generally compressed. Compression comes from the need for storing more files in a given space with an inverse relationship to quality. The higher the quality (meaning less compression), the larger the file. Looking at it this way, uncompressed means larger file and therefor more information. In photo editing and finishing, the amount of information (PIXELS) is important and generally a determining factor in overall quality and final print size. The confounding factor is that compression does not decrease actual pixels, rather, it looks for patterns and comes up with a smaller, more efficient way of describing those patterns. JPEG uses a complex variety of algorithms that look at each color a pixel has and associates it with the neighboring pixels. The higher the quality JPEG, the tighter the sample of pixels and hence the larger file size. Uncompressed does nothing to save file size and each pixel is left untouched. The best way to determine your needs is by looking at your workflow and your final product. Uncompressed files mean more hard drive devoted to your files whereas some compression may not be noticeable AND saves you some hard drive space. See JPEG Compression notes.
There is a myth circulating that JPEGs degrade everytime you open them. This is not entirely true. When you open a text document to read it, you are not changing it from it’s original version and therefor do not resave it (it will look the same the next time you open it). The same is true with JPEGs. However, if you manipulate the photo, and resave – you are compressing an already compressed file. Most of the time, if your file is the same number of pixels in the same relative array (a horizontal picture stays horizontal) – there is no, hypothetically, noticeable difference. However, if you change the number of pixels or the orientation of the array (rotate an image 90 degrees), you are now invoking damage to your file. How much damage? Not much, at first. We ran a quick experiment with Photoshop actions to see what different levels of Compression (from 0 Quality to 12 Quality) did with repeatedly rotating and saving a generic file with a variety of colors. See the results! We found that a compression of 12 (MAXIMUM quality) did more damage than a compression of 10, as well as that there was not noticeable difference between 8 and 10. If it were to be a rule of thumb, 10 should be your maximum value used when saving JPEGs.
Another of the most difficult concepts to understand when dealing with digital photography. In the digital world, resolution is a relationship to the pixel dimensions, but gives no indication of actual pixel dimensions alone. Someone asking for a 300 dpi photo can be asking for really anything! Although the actual size of the pixel is determined by the device creating it, the relative size to a unit of measure is the resolution. Resolution in digital images is often mistakedly referred to as DPI – or dots per inch. However, it is truly a pixels per inch/centimeter (PPI or PPCM) relationship. DPI comes from the print and screen world. Most CRT monitors are able to project 72-96 dpi. They are dots because that is the nature of the CRT tube, it combines light dots (circular) to create a single color or approximation of a pixel (square). For print media, it refers to the capability of the printer heads (i.e. inkjets spray tiny circular dots onto a page in various combinations to approximate square pixels in an image. If there is enough difference between the number of pixels in an image and the print or display pixels – you get an approximation that either looks jagged (many dots to less pixels) or very smooth (many pixels to less dots). “Lo-res” refers to images typically found on the internet. Images that fill a portion of a standard screen at 100% and appear extremely jagged when printed as an 8×10. “Hi-res” is relative to the output size. Generally it means that there are enough pixels to support a perceptably smooth image at a given output size. Both indicators are relative to their output size. While a file may be Lo-res for an 8×10 output, it is a Hi-res 4×6. The human eye can discern nearly 260 different values of color in an inch. Most people round up to 300 dpi – figuring that a 300 dpi image is more than enough to be a good approximation of the actual image.
Resolution also is affected by viewing distance, among other environmental issues associated with vision. Viewing distance, however is the major contributor for apparent resolution. Example: a billboard on the side of the road has a very large viewing distance. Images are sharp and clear as you drive by them. However, if you were to be a worker putting up the billboard, you would see very large dots and not be able to make sense of it. (Billboards are typically 12 dpi or less!). The real resolution (12 dpi), appears to be 300 or more dpi at a viewing distance of 50 feet, for example. As you move closer to the printed image, the apparent resolution gets closer to the actual resolution. When printing your large prints, be sure to consider your ideal viewing distance as well as overall pixel dimensions. Try this: print a 4-base scan from a negative or positive at 4×6 and 8×12. Place the 8×12 on the wall and hold the 4×6 up in front of you at arms length. Position yourself so that the 4×6 appears to be the same visual size as the 8×12 on the wall. Try to notice the differences between the two. What do you find?
From PICture ELement. This is the smallest amount of image information in a given image. Actual PIXEL dimension is relative to the resolution of the image, as well as the device creating the pixel. In digital cameras, typically referred to as Megapixels (MP). The higher MP, the smaller the detail you can capture (or the larger you can print without loss of perception of resolution).
This is a term referring to the printable or displayable range of color. You can also refer to this as Color Space or dynamic range. Colors out of gamut generally implies that the colors described on screen will not be reproducable on a particular print media. Out of gamut colors typically include neon colors since neons are colors created from light emitted versus light reflected. Different substrates or media have different gamuts.