TCPglobal - news, views and issues on total cost of printing

Issue #0706/2 - Users risk spending nearly three times the amount they need to for their home photographs if they choose the wrong AiO/printer and could lose as much as 59% of their ink.

Four-colour photo printing usually means three-colour photo printing. The anomaly lies in the fact that there are usually four inks installed in the machine at the time of printing (with most four-colour desktop printers).

There are a few printers where this is not the case. These are mainly the portable devices that hold only a tri-colour cartridge but there are a few desktop devices (such as the very cheap Lexmark X2350 AiO that also take only a tricolour cartridge – hence producing very expensive and unsatisfactory mono prints).

Likewise, 6-colour photo printing may mean either 5-colour or 6-colour printing but, where it means 5-colour printing, this normally means that the black contained in a tri-colour photo cartridge is wasted unless the user keeps that same cartridge configuration for printing black text.

In theory, 6-colour photo printing offers higher quality than 4-colour. However, we see Canon now producing 5-colour machines where the basic photo printing is 3-colour with the addition of a photo black and a text black. This approach is very much in keeping with the company’s decision to limit digital camera resolution in order to maximise image quality.

What this most definitely does mean is – the more colours used for printing, the more expensive the prints are.

This can be seen most graphically in the chart below, of cost of ink used, that clearly shows that the two 4-colour machines are significantly less costly to operate than the 6-colour machines – at least 29% less costly and up to 65% in the case of the machines in this line-up.

Cost of ink per typical photo at 10×15

If we were to add 8-ink and 9-ink printer configurations to this chart, we’d see the cost rising further (for illustration, see TCPglobal Issue #0410, "Inkjet All-in-One lab tests – Printer roundup").

It is Lexmark’s P4350 that presents itself as very much the most expensive AiO – by 60% over the Hewlett-Packard C4180. There is little to choose between the Hewlett-Packard and the Epson Stylus Pro RX620 in terms of cost of photo printing – but – check out the articles on performance and Cost of Office Printing (future issues of TCPglobal) to find out which of these machines actually represents the best all-round value for money.

With Canon’s MP-450 just failing to take the lead slot, this leaves us with the Brother DCP-330C giving us the lowest cost for photo printing. Apart from the obvious pricing of supplies having an impact on the Cost of Printing, Brother’s DCP-330C is built on a new print engine with what amounts to a radical new set of algorithms for determining the amount of ink placed on the paper.

Applying these new algorithms has allowed Brother not only to reduce the amount of ink used, and therefore the cost, but also to improve the overall print quality and realism of the resulting photos. The quality implications will be discussed in the article on Photo Print Quality that will be published in a forthcoming issue of TCPglobal.

One illustration of the difference in approach from the various manufactures can be found in Table 1. below. Here we see the number of photos produced by each cartridge on each machine.

Table 1.
Photos produced by each cartridge during photo testing, together with Cost of ink per Photo.

	C	M	Y	K	Pc	Pm	CMY	Photo	Cost per photo (£p)
Brother DCP-330C	141	150	150	Used for cleaning					14.09 pence
Canon PIXMA MP-450				Used for cleaning					15.79 pence
Epson Stylus Photo RX620	416	334	266	569	192	129			22.19 pence
HP Photosmart C4180							100	106	25.20 pence
Lexmark P4350							62	82	40.15 pence

At this point, we should make a few comments on the photo suite used to undertake these tests.

The full PhotoSuite can be viewed at:
CharisCo Printer Labs - PhotoSuite

When selecting photographs, we were looking for ordinary, average images that would give a fair representation of the type of photographs the typical home photographer might take. Combined with the fact that they were selected three years ago, this means that none are super-high resolution (max 5MP, min 2.1MP) but all are capable of being printed at A4. Each image also presents a challenge for the printer in one way or another.

However, the main point that is relevant here is that they were not selected for balanced colour content. Yet, when testing the images for colour content, we found that the average CMY content (i.e. theoretical ink coverage for each colour) was an almost perfectly balanced 70% per colour.

So, in theory, usage of the three primary inks should be reasonably even for this test suite.

What we see with the Brother ink tanks is that the balance of ink usage is very closely balanced, with just the Cyan running out a few photos before the Yellow and Magenta. If we do a simplistic additional calculation on the other machine with individual ink tanks, Epson’s RX620, we can work out a rough estimate for the balance of inks as if the Epson were running a 4-ink configuration (Table 2).

Table 2.
Estimated number of photos each Epson cartridge should be capable of printing if it was a 4-colour device.

Epson Stylus Photo RX620	C	M	Y	K	Pc	Pm
Actual tested photo yield per ink	416	334	266	569	192	129
Assumed yield as if printing 4-ink	224	205	266	569

Although this is merely illustrative and not based on testing or an ink density formula, we can see that the balance of ink usage is not as close as those from Brother (30% against 6%) but is not hugely unbalanced.

However, the point in making this comparison is that we do see a remarkable difference in the approach taken by the different manufacturers with regard to ink usage between the three primary colours and the two photo colours.

Here we make an alarming discovery regarding the RX620 – that the two photo inks, and the Photo Magenta ink in particular, have an exceptionally short life, yielding 61% (Photo Magenta) and 54% (Photo Cyan) fewer photos than the primary inks.

By contrast, Hewlett-Packard’s C4180 is well-balanced, giving us 6% more pages from the photo cartridge than the standard CMY cartridge. Lexmark’s P4350 is more unbalanced than the C4180 but takes us even further from the Epson by giving us 32% more pages from the photo cartridge than the CMY cartridge.

So, what difference does this make to the user?

Where the tri-colour configurations are concerned, it does not make a significant difference because changing cartridges does not instigate any major ink wastage when cartridges are primed and cleaned. However, it does make a difference where the printer configuration includes individual tanks and a cleaning process that wastes ink in order to purge air from the ink channels.

This mainly refers to Epson’s Micro Piezo system. Brother claims that its sealed system is not susceptible to air intrusion, a claim that appears to be borne out by the test results, which show that very little ink is wasted in standard cleaning cycles – probably less than half the ink used by the Epson machine.

It is then the fact that there are six tanks on the RX620 that contributes to more priming and cleaning cycles than a four-ink system like Brother’s DCP engine, and unbalanced ink usage means that there is little chance of needing to replace two cartridges at the same time (more efficient both on time and ink wastage). It is interesting to note that the DCP-330C required a change of both Magenta and Yellow at the same time whereas Epson tanks were all changed at very different times – more interventions, more time, more ink wasted through priming and cleaning.

However, the most alarming factor was that the Epson used the photo inks so rapidly, using about 34.7ml of Photo Magenta ink compared to 14.5ml of the primary Magenta. Similarly, about 28.7ml of Photo Cyan ink was used by the time 13ml of primary Cyan was used.

Overall, we found that the cost per millilitre of Epson colour inks was about 69 pence – the cheapest ink in the test! Although Brother’s colour inks cost about 87 pence per millilitre, the use of only four inks gives us the lowest overall cost per photo.

Comparing this with Hewlett-Packard’s C4180 raises another somewhat alarming factor. Even though the photo cartridge from Hewlett-Packard (No. 348) gave us more prints than the standard tri-colour cartridge, the cost of ink used was a massive £2.33 per millilitre – the most expensive ink in the test!

Now, clearly we need to explain why this cost is so high.

Containing a quoted 13ml of ink, this is a tri-colour cartridge containing black ink along with Photo Cyan and Photo Magenta inks. During the testing, the Photo Magenta ink in the cartridge failed at 106 prints. At this time, just 5.6ml of ink had been used – only 41% of the ink contained in the cartridge and meaning that a massive 59% of the ink was wasted as ‘inaccessible’ – mostly black.

This is the main contributor towards the C4180 having a Cost of Photo Printing that is 79% higher than the Brother DCP-330C. If ever there was a case for individual ink tanks, or even for refilling cartridges, this is it!

Just for the record, the CMY tri-colour cartridge used 7.05ml (100%) of ink to give us 100 prints – at a cost of £1.83 per millilitre, a cost that is equivalent to both of the Lexmark cartridges used. It is Hewlett-Packard’s much more efficient use of ink that gives us the lower print cost.

Further alarm comes from the fact that the Epson RX620 used three-quarters of its black ink by the time the Cyan was exhausted, whereas both Brother and Canon machines used miniscule amounts – equating to about 2.5% and 4% respectively. Causing this high black ink usage on the Epson is mainly the frequency and wastefulness of the priming/cleaning cycle that the print engine undergoes, particularly when ink tanks are changed.

Much of this is technicality. Any one of the manufacturers could reduce or increase the Cost of Photo Printing merely by making a marketing decision to do so.

Brother has decided that its objective is to undercut its competition. We could say that the technology used by Brother is the most flexible for permitting this approach because it uses individual ink tanks and a sealed system that prevents unwanted air from entering the system, thus reducing wastage from having to purge that air.

Hewlett-Packard and Lexmark are both hampered by the use of a tri-colour photo cartridge with its inherent black ink wastage, while Epson will always suffer from heavy ink wastage from cleaning cycles. In contrast though, Canon’s device, being four-colour, is able to compete keenly with Brother, wasting little ink in the process.

Cost of photo printing is only one element in the grand scheme of things. This must be balanced against the cost of office printing, performance, reliability and print quality, aspects that will be covered in forthcoming issues.

For now, though, suffice it to say that Brother has succeeded in its goal of undercutting all the competition on Cost of Photo Printing with a machine that is attractive, slim and functional, while Lexmark does not disappoint its critics with a machine that is not only costly but is flimsy, unreliable and irritating to work with.

~End~

This entry was posted on Friday, February 23rd, 2007 at 12:02 am and is filed under Hardware, Supplies, Pricing, Comparisons. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.