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Making Lab Quality Digital Photos?
photoFinished asks: How do most photo labs produce their digital prints? It seems to me that there should be a machine that uses an LCD to create a virtual negative to expose standard photo paper to, resulting in a standard-type photograph as the end result. However, since just about every CVS, Walgreens and other pharmacy advertises the ability to produce prints from your digital photos, I'm wondering if there's a quality difference between the various stores? I can produce a 4x6 on a $100 name-brand ink jet that appears virtually identical to a lab print when you look at it behind glass, the only difference is a light reduction in the smooth/glossiness you get from a regular print. Does anyone have information on the methods used by the various chain pharmacies produce their prints? I'd hate to think that the $0.40 I'm paying for each 4x6 is actually nothing more then the result of an expensive ink jet printer. Sorry if this is one of those 'you should try google' type of questions, but I couldn't find the answers I was looking for."
You must also be nuts (or desperate) to pay $0.40 for prints. $0.20 is typical for Costco/Sam's club/Wal-Mart Costco is $0.17 Sam's claims to be as low as $0.11
FYI: The Nortisu I usually use at my local Costco recommends preparing digital files at 320 dpi, as that is the printer's native resolution. So you might be able to do higher resolution from a home printer, but it's hard to beat the durability of standard prints.
BMost of these digital print makers do actually use a photographic process. There is no print negitive involved, because the computer can take the regular image and invert the colors easy enough.
It then takes the inverted image and uses colored LEDs to expose the piece of print paper in the size that you have picked.
The reason these machines are called "mini-labs" is they have a full photo lab inside of them. Once the film is exposed by the LEDs it is then developed, fixed, rinsed, and dried all inside that box. Then the final print emerges.
The technology I hear mentioned most often with reference to authentic prints from digital is "micro light valve array".
A company called alpine makes one for about $500 (the 1300 model). This is the same technology that wal*mart and wolf/ritz camera and all the internet printing places uses. Here are some links:
m n kjet/Alps_color_inkjet_printer.htmlk ipedia.org/wiki/Dye-sublimation_printer
http://science.howstuffworks.com/question583.ht
http://www.digital-photography.org/alps_color_i
http://en.wi
moox. for a new generation.
My exposure to these technologies was on the R&D end, not the business end, and I've since left Kodak.
:-) - HD is for wimps. These systems were replaced by the LED systems.
Most modern minilabs (be they Kodak/Noritsu, Fuji, etc. (a lot of these minilab systems are actually contracted out, but that's another discussion) use digital subsystems with wet front and back ends where appropriate.
Digital images are imported directly through obvious means - bits go in the hole. Silver halide negatives are developed and then scanned and stored locally on the minilab. The digital images are then adjusted through a combination of automated improvements (such as Kodak PerfectTouch) and manual tweaking, depending on the shop you go to and the level of service they offer. Automated only = cheaper. Current systems then use rastered or scanned LEDs in an RGB configuration (Some may also use lasers, but all the ones I've seen were LEDs - they're cheap) to expose the photographic paper, which is developed using traditional wet processes.
In the past, the first digital Kodak minilabs used little 6" CRTs with 4000 lines of resolution (made in New Jersey, I think) to project the images onto the paper. There was talk of stepping that up to 6000 lines, but I don't know if that ever happened. I could be a little off on those numbers - I'm pulling them from memory from years ago. But they certainly ended the NTSC/PAL resolution debate
Note that wholesale photofinishing labs still use traditional optics - for all the grooviness of digital systems, it's hard to beat a massive spinning system of traditional optics churning out thousands of prints an hour (we're talking on the scale of a print a second - fast!)
Most walk-up kiosks use thermal/dye sublimation printing systems, which have excellent print quality and durability, though they're expensive. A mylar donor ribbon coated with CMYK+finisher dyes is heated by a pagewidth linear array of diodes at ~300dpi and pressed against the receiver paper. A separate pass is made for each color. I'm not aware of any minilabs that use dye dub printers because of the speed limitations.
Inkjet technology is starting to penetrate the kiosk market, but there's a lot of maturing to still take place.
Your immediate observations are correct: silver halide photographic paper is more durable and usually glossier, which most consumers associate with quality. Since there are a wide range of inks available on the market (every printer manufacturer has many types of inks), paper manufacturers have and optimization problem in balancing quality/durability/color reproduction/light fastness.
As for the quality between vendors, there certainly are differences - though how much of that is tied to the digital algorithms and how much is tied to the processing hardware these days I'm not sure. I suspect it's much more the former. Your best bet is to find a local shop with well-trained staff that actually knows how to use the minilab, rather than the summer job teenager who doodled pictures of Bevis and Butthead (or Spongebob, or Thundercats, or whatever the kids are into these days) during their training class.
At this stage, throughput is the big technical bottleneck remaining for inkjet technologies to penetrate the kiosk and minilab markets. Ecologically and economically it's a 'no brainer', so all the major players are trying to produce solutions. Kiosks will probably be the first to make the transition. Brother, Sony, and another company that escapes me at the moment (in the UK?) have publicly demonstrated pagewide technologies, and I think Xerox had one operating in their labs before they shut down the inkjet effort a few years back. Some of these demos have been around for years. Someone from the inside needs to write a book about the Kodak-HP joint venture ("Phogenix") in making an inkjet minlab system - but it's probably still a little early, since the technologies the two companies were bringing to the table for the joint venture will appear in future products of their own. There are some entertaining stories involved - classic corporate America.
There's quite a difference between printing your own pictures and having digital pictures developed at a professional lab. Home printed pictures, after less than a year, will start to fade. This will not happen with pics developed at a photolab. If you wish to keep those pictures for archival purposes, get them printed professionaly. As others have stated 0.40$ a picture is way too expensive. I pay 0.15$ CAN a picture at Costco.
It's better to burn out than to fade away
Look into an Epson R1800 for inkjet photo printers. It'll set you back $550 but it has a gloss optimizer that'll give it the same protection as regular photo prints.
Working with Fuji and some of the major photo companies, the shortcoming lies in their printers not being able to do full bleed 8x10.
Hope that helps a little.