Digital Imaging

 Color and B&W digital Printing

Intro

As a custom and exhibition printer for more than a quarter of a century, and as a person interested in digital photography since the introduction of the Mavica camera from Sony in the 1980'S, I'm excited where digital is going and how fast it is getting there. Below is a discussion of the state of the art in fine digital printing.

Papers

There are so many papers to choose from it really is amazing. I have forty samples right now and there has to be another forty out there. There are 100% rag, etching papers, watercolor, rice papers, textured, resin coated, polycarbonate, canvas, photo enhanced, fiber base, thin, thick, and on and on. Where traditional photographic papers are becoming fewer and fewer, the choices for digital are becoming greater and greater. The problem is every paper and ink combination needs it's own file to print correctly. That is, the same ink will look different on a different paper and needs it's own profile or set of instructions to the printer to print correctly. So, what this means is that as a printer who provides services to a client, one needs to have several paper and ink combinations worked out to satisfy the clients needs. I have many and cover all the most popular papers out there. We use Greytag/McBeth Eye One for color management. My goal is to have more paper and ink combinations for exhibition printing then anyone else.

Inks

There are several manufactures and types of inks out there to consider. Dye and pigment inks cover most of the spectrum of available inks today. The main difference between Dye and Piqment is that dye penetrates the paper fully on a glossy paper and piqment generaly leaves some ink on the surface, or can't adhere at all. Dyes are inks that stain the paper and pigments deposit microscopic particles into the paper. Ink being left on the service causes "Bronzing", (the warm color reflected in the scheen of a glossy paper) and "Gloss Differencial", (the effect where the spetral highlight meets the tonality of the paper, a wall where all tones just drop with no gradation.) Pigments are considered archival and dyes are associated as having limited longevity, in that the dyes break down and fade or change color in a short amount of time.

An issue with all inks is Matamerizm which is the change of color the prints have depending on what light they are viewed in. Tungsten, daylight, or combinations thereof. The inks absorb light which then reflects the color of the ink back to you changing the whole tonality of the print unlike traditional emulsions that have solid opaque oxidized silver that makes up the image and are imbedded in the papers emulsion.

I have to say that when we talk archival I think we should first talk permenency. Most ink-sets printed on "Art Papers" as opposed to the Microporus RC will run when exposed to water. The materials are acid free and rated over 100 years under UV lighting fade testing, but when you give it the "Spit Test", most do not pass. RC papers can be put under a faucet and not have them run. We are told that these microporus papers have many tiny holes in the emulsion that let the ink in, and with that it also alows contaminents from the atmosphere to get in quicker then a swellable emulsion that drys around the ink and encapsulates it, therefore claiming better protection. The only trouble is it just swells up when exposed to water and  humidity and gives up all it's protection and the ink runs. So, we see just the revearse of traditional silver printing, in digital printing the RC's may be the more archival because they firstly have permancy, and secondly they are rated 70 plus years to begin with and are ph neutral. Not only will they last, they won't run. Rags have to be sprayed. Now I'm not saying that we don't like the look on the Art Papers, I'm just saying that there are permancy issues with them. What we need is better emulsions on these very expensive "Art Papers".

Individual manufactures have different charateristics within their sector of the ink world. Epson's Ultra-Chrome hybread pigment chromimum ink-set is probably the most wildly used. The new K-3 improvement has corrected a lot of things from the old. Matmamerism and bronzing are almost completely elimenated and the colorspace has been widened about 15%. The D-max in the blacks is better, the dots are finer, and the tracking of the paper is better. All in all a great improvement. This ink-set can go on about any kind of surface and substrate.

Carbon Pigment is for Grayscale printing on "Art Papers" only.  The pigments can't get through a gloss surface of any kind and just powder up on the surface where one can blow it off. It has beautiful rich velvety blacks and a look all it's own.

Lyson's archival grayscale dye ink-set is ineresting in that an archival dye ink-set would not have a bronzing or gloss differential issue although it does have a matameriam problem. We found that the ink-set looked good on a couple papers in it's most neutral mixture. On several RC papers it looked "Ball Point Penish" and tended to solarize in the shadow. We found it interesting but thought the K-3 looked more photographic.

HP's archival dye ink-set has been interesting. We see this as an ink-set that came up from the display field of the printing sector. It's only archival on it's own paper becase of the incapsulating funtion it needs to protect the pigment. Anyway it works and the RGB has a nice gamut and is resistant to water. We find we liked the Epson K3 for exhibition work better, especialy with grayscale printing. HP is releasing new printers soon, and odly enough it has changed to pigment. We will see.

Canon has three new printers out and there new 12 color pigment machine has great potential. We are still waiting to see our first samples to judge for ourselves.

Printers

There are four main printing options in digital printing. Dye Sublimation, which fuses colors of mylar to the surface of a base, Fuji's silver halide based system which resembles the traditional process and generally found only in it's small commercial Fujix machines,   Ink Jet printing, called Glicce by some, being Iris, Epson or any other inkjet printer that sprays ink onto the surface of a substrate, and Digitally exposed "Type C" printers such as the LightJet, Fuji Frontier, or Lambda printers. All the printing methods have come a long way. Dye Sub has lost favour over the years but is seeing a come back in small consumer machines. Fuji Frontier printers are high quality machine printers with the limitations of size, manipulation of the print, and paper choice that any machine printer would have. They are very popular with labs providing wedding photographers and other photographers cheap fast commercial prints of the traditional silver based RC color print variety. Digital type C printers expose traditional type C paper with a three color laser or other  exposing system and then process the exposed paper in a traditional type C print processor. The results are better then traditional analog printing from an enlarger. We view this set of printers in two categories, machine printer and custom/exhibition printer. The machine printer of choice is the Fuji Frontier mentioned above, but the state of the art in this type of printing is the LightJet printer. Capable of 50" and 70" wide prints by 100' their output is equal to 4000 DPI printing. Although both of these machines are the best for type C prints and surpass traditional lab printing they do have one flaw, Chemical fog. Since these printers are using traditional color paper and chemicals they inherently have a change in their emulsions effected by the chemicals. Compare any ink jet RC print with these papers (Fuji Crystal being our favorite with 70 year longevity) and you will see the ink jet has a whiter base. Which means that your whites are being effected in the digital exposed type C print. Inkjet has the most versatility with outstanding quality, keeping in mind the issues with choosing an ink set. See above for information about inks.

Scanners

There are three types of scanners. Film, drum, and flatbed. Film scanners are for high resolution scanning of film for photo exhibition grade printing on down. Flatbed scanners depending on manufacture give less quality. Drum scanners are considered state of the art and are for reflective as well as for film. The most important points about a scanner is the PPI or pixels per inch it can produce (resolution), it's dynamic range (it's ability to record range of stops in a scene), density of scan called "Bit Depth", how many bits of information it can record controlling tonality or smoothness of tone.

Most film scanners purchased today for the professional photographer are rated about 4000 PPI, 42 bit color, at 4.2 density such as the Nikon Cool Scans, Kodak's, and Polaroid's. Some problems with these scanners is that they produce digital noise because of the close construction within its body and issues with sharpness due to flimsy negative holders. Flatbed scanners have less resolving power until you get to the $20,000.00 level and are used mostly for reflective art but can be rated for film as well with OEM film adapters. Drum scanners considered state of the art have direct lens to art work design and PPI's of over 10,000 plus, they are used for the most demanding of work. One has to consider the price of getting a drum scan. They are the most expensive of scanning equipment and scans are costly. Operating a drum scanner is slow in the way art work has to be attached and puts a damper on production which adds to the cost of the scan as well.  A very impressive intermediate scanner which produces quality that matches the quality that of a drum scanner is the Imacon virtual drum scanners for the professional lab with 8000 PPI, 48 bit color, and a claimed 4.8 density, and has an ease of use that affords very reasonable priced scans.

 RIP Systems

Rastor Imaging Processing software is the software that controls the interpretation of information from the computer to the printer. All RIP's are not created equal. When one buys an Epson printer to use with either the Mac or PC platform in conjunction with Photoshop, they are using the Epson drivers to print. You could consider this a very small RIP system. The better the RIP the better the results and the more you can do. The RIP's control tonality, DPI, color, the structure and placement of the dots, placement of the image, production capabilities, and postscript function. Some are visual, others are not. But in any case, a very, very important tool in fine digital printing.

 Where I am now

After three years of providing high end digital services we are equipped with a Imacon virtual drum scanner and a Epson 1680 flatbed scanner for reflective art and 8x10 negs, which we are in the process of replacing with a tabloid size unit. We have two Epson 9800 set up, one for photo and one for mat black printing, and a 7000 printer set-up with the new K6 ink set by Con. We utilize two RIP systems which we feel are the best for photographic printing and employ Greytag/McBeth Eye One for color management and profiling. We use Extensis Portfolio for asset management and of course Photoshop for image manipulation. We also employ several after market programs for advance image manipulation that we find superior to Photoshop in certain functions or tools. We are in the process and should finish this month to add a complete archive server and back-up system to handle the growing number of files we maintain.

We are constantly reviewing ink-sets and papers to see what's the best out there for our clients.