London Drugs Print Quality – Wet versus Dry Technology


Backgrounder

I recently had a chance to compare some prints made on the new “dry printing” technology from the photo labs at London Drugs.  I had a print previously done by them on the traditional photographic chemical “wet” process (often referred as silver halide technology) and was able to informally compare with a new print done on their latest dry technology of the same digital file.  London Drugs’ photofinishing equipment supplier is Noritsu, who have provided both the wet and dry technology printers.  London Drugs recently received some publicity from Noritsu on the launch of their new printers.

In this blog post, I’ll outline my initial thoughts and impressions on the two technologies and do a bit of an informal shootout in a few categories.

Technical

Going beyond the marketing speak, Noritsu’s “dry print” process incorporates at its heart Epson’s four-colour inkjet technology, an excellent basis to start from.  I figure the term “inkjet” evokes the wrong image in the minds of consumers, specifically low-cost home printers, which are notorious for costing less than the cost of ink to refill them, and this association seems to compel marketers to substitute terms like “dry printing”, or in fine art printing circles, the term “giclée”.  This association is unfortunate, since there is a large gap between cheap consumer inkjet and high-end inkjet, as much as there is in between car makes and models.  Inkjet done properly can be very good indeed.

Inkjet technology, traditionally a higher-cost medium, is approaching a price point where prints from specialized high volume printers can start competing with the traditional silver halide minilab machines.  The environmental benefits of dry printing are also obvious — the wet process requires lots of chemical mixing and the printers discharge effluent that has to be treated, while the dry machines do not.  Colour inconsistency caused by variations in chemical strength is substantially less of a problem on inkjet, also helping to reduce overall waste from having to redo unsatisfactory prints.

The Prints

While scanned images of the prints don’t really convey what they’re like in person, I’ll show them here for completeness.  The inkjet print of Amy to the left is more faithful in colour to the original digital image although the real differences in colour aren’t as dramatic as it is here; I blame the scanner’s automatic exposure and colour settings in this case making the scan of the wet print a bit warmer in colour.  My descriptions are based on looking at the actual 4”x6” prints side-by-side, not at the scanned images, so you’re better off taking my word for it!

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Initial Impressions

The dry print gives an extremely good first impression.  When viewing the dry print after the wet print, there is an impression of greater clarity in the dry print that is instantly noticeable — the difference between is like viewing a scene with and without a glass window in the way.  The dry print paper also has a different surface texture and visual quality.  Depending on the lighting, the dry prints have less glare to them, adding to the extra impression of clarity.

Colour

Blacks are deep, dark, and black, without becoming the muddy brownish-bluish colour it is on wet prints.  Shadow details close to black are also rendered very well, keeping their details well.  This is probably the greatest difference I see between the two.  Amy’s dress is black, and details in the dark fabric definitely show better on the dry print than the wet.

The gamut (the range of colours that can be reproduced) of inkjet technology is wider than silver halide prints, so saturated colours like deep reds and purples that traditionally lost small nuances of details in a wash of similar colour are very well reproduced on the dry print.  Flower photographers should rejoice!

Compared to the original digital image on a colour-calibrated monitor, the dry print also matches the colours very well, so the overall ability to get a good colour match against what you see (presuming a colour-managed workflow) is good, thanks to the wide gamut and accuracy.

All in all, the colour on the dry print pops.  So much so that people might be a little surprised at first, sort of like when CD’s first came out and people were a little unused to the accuracy, clarity, and dynamic range of the sound.

Feel

Like most inkjet prints, fresh-off-the-printer dry prints have a slight vinegary smell that dissipates in a few days.  Fresh-off-the-printer wet prints have a similar sort of chemical smell, though less acidic, and also dissipate.

The wet print has a thicker, smoother coat on top of it that is shinier and reflects more glare back, while the dry print is a little grabbier in texture (it can squeak more if you run your finger over it) and better anti-glare properties.

The paper stock used for the dry print is not quite as thick as the Fuji Crystal Archive paper used for the wet print.  However, I’ve recently heard that the thick Fuji paper may no longer be available and that some thicker inkjet paper may be coming on the market.  So I think this concern may ultimately be resolved.

I did an informal scratch test on the paper surfaces using my fingernail.  I initially expected the grabbier dry print surface to perhaps be a little less resistant to scratching than the slicker wet print, but I was able to scratch both with about the same ease.  In fact, I think the wet print suffered more ultimate harm than the dry print as once you scrape to the paper below, the surface coating is easier to scrape off (just like if you are scraping paint, once you get through between the surface and the paint, the paint comes off easier).  It was a bit harder to do the same on the dry print.

Image details

Inkjet printers do not print continuous tone images — they are made up of microscopic dots of ink dye of one of each of the four ink colours.  The dots are more noticeable in large areas of lighter colour, where fewer ink dots are required and they stand out more in contrast with the white paper, and I find that it imparts a slightly grainier feel to the image in these areas.  Grain isn’t always bad thing as it can impart an illusion of high detail or texture even though they aren’t present in the first place.  Normal viewing of my prints shows good crisp, sharp details on both, and the only area where I saw any appreciable difference between the two was on an area of the image with fine hair (fine hair is always a good torture test for resolution and sharpness).

Below are the small crops (inkjet left, silver halide right) of that area.  As a reference, this is a magnification of an area of about 1/2” wide on the print.  There is difference in extremely fine details, such as in the fine strands of hair and eyelashes that is only just visible when viewing the print at normal distances.  I found this somewhat unusual since both prints seemed quite equal in sharpness except in this area.  I feel that these differences could be in part due to differences in the resampling of the original image to the specific printer resolution and sharpening algorithms applied to the dry and wet prints.  You can also start to see the individual ink dots, or at least the grain effect, as well.

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Banding

Extremely small banding artifacts are sometimes visible at very close inspection.  Banding is the appearance of faint horizontal lines caused by microscopic variations in the feeding of the paper through the printing mechanism (the print head traverses back and forth on one axis as it lays down the ink dots and the paper has to be fed through extremely precisely on the other axis).  Any subtle variation in the paper alignment or feed rate may show as a line in the print where a slightly wider gap or overlap with the previous print head pass occurs.  A similar problem with lines running through the print can also occur on inkjet printers if a print nozzle is clogged, but it is very obvious when this happens.  If you stare at the following image (about 1” wide on the real print) long enough, you might see a subtle, horizontal line about halfway down (right below her fingernail) that runs across the entire width of the image.

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Again, in most normal print viewing distances this is usually not visible, but continuous areas of the same colour could make it easier to spot banding if it does occur.  I presume that proper maintenance and calibration of these machines will be extremely important to retain good performance.  Similar problems can happen with wet printing technology as well — dust or other grit can also get embedded into the soft parts of rollers or squeegees and cause scratches to occur on the print surface.  These problem prints are normally spotted by the operator and never get into the hands of customers.

Getting the best quality

Out of camera JPEGs should look really good on the new dry technology.  London Drugs’ philosophy of having the lab technicians colour correct and inspect each image does help to deliver overall pleasing images; their overall “look” favours punchy, contrasty, saturated, customer-friendly images. 

Having viewed and printed thousands of images myself, my personal feeling is that all images do need some level of adjustments for best results, and while automatic correction technology has come a long way, there’s still no substitute for the human eye to spot and correct colour variations.

So while most people are best off allowing the lab operator to colour correct images, there is always the option to request images, especially those with a deliberate colour treatment, be printed directly without corrections.  It goes without saying that if one is to use this option and perform the image corrections manually, then it should be done with a properly colour managed and calibrated system.  For example, laptop displays typically tend to be on the bluish side in order to provide an impression of brightness, and these tend to skew colour.  The best colourspace to set your files to for printing to get a good match, as with most photofinishers, is sRGB.

Though problems have been a rare occurrence in my own experience, London Drugs has always been very accommodating of reprinting items to my satisfaction.

Conclusions

The jump in quality of pictures on dry compared to wet technology is quite obvious and has to be seen to be experienced.  The ease of obtaining image quality previously only available through much costlier home inkjet printing is a great thing, and is as easy as submitting images to one’s local London Drugs.

While I have written about downsides such as the lack of continuous tone, detail loss, and potential for banding, in actual practice and normal viewing distances, they are hardly noticeable by most people (if they are present at all), so the edge goes to the dry technology for its superior colour fidelity.

For professionals, the ability to get high quality prints at competitive pricing may make the need to maintain ones’ own inkjet printer (and the associated cost of ink, paper, and wasted paper) a lot less compelling.  Personally, I’ve chosen not to have my own printer for that very reason.  I hope to test the London Drugs offerings in the future to see how their enlargement sizes compare to both high-end inkjets and traditional wet process.

Having had the (messy) experience of darkroom work, I do lament somewhat the passing of photographic paper, which, as I discovered in my analysis, still puts up an impressive fight against the newcomer.  But there’s no denying the stronger and more accurate colours that the new dry printing technology brings, nor is there denying or slowing down the inevitable march towards the new technology just as there was with digital imaging.  Also the “green” aspect of dry printing is something that we can all enjoy.

* Full Disclaimer:  London Drugs is a client of mine.  This evaluation was conducted purely on my own time and without any prior knowledge or pre-arrangement on their part.  I use London Drugs for my personal and professional printing needs and recommend my professional clients do the same.

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