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Motivation is a photography blog that discusses the creative aspects of photography. The posts will include thoughts about images and their interpretation, photographers and their work, technique, workflow, my ongoing projects, and perhaps even the occasional off topic rant.

It Might Be Worth Knowing Your Inkjet Printer

I embarked on a small 15 minute project that I thought might be worthwhile  while I was reading Martin Evening's new book on Lightroom 4.  In it he notes that the printer profiles that one utilizes in Lightroom and Photoshop for specific printers and papers typically automatically map the very dark tones to levels where the printer can produce detail (ie a level of say 1-5 would be mapped by the profile to a new level where the printer can generate a bit of detail by visually producing differences in the black tones).  However, it is much more critical that one map the highlights to levels where the printer can produce detail, as profiles typically do not accomplish this very well. For example, 255 is pure white and any pixel at level 255 will print to paper white. This means that pixels at 254, 253, 252 etc SHOULD have some ink and that the levels SHOULD be able to be discerned from each other.....after all if you can't tell a 254 from a 253 then there will not be any ability to discern details or contrast in that region in the print.  But the SHOULD is not reality and all printers are different.  It seems it would be useful to know what level one's printer can start showing detail so that the brightest highlights with detail can be mapped to that level.

So I did a brief experiment.  I made a new file in Photoshop and with the marquee tool made multiple squares and then  using the Edit>Fill command filled the squares with neutral colors at 255, 255, 255 and 254, 254, 254 and 253, 253, 253 etc all the way down to the upper 240s.  My goal was to see where my printer started to produce printed patches that were able to be seen (thus, not printing paper white) and if one were able to denote differences between the patches (thus, denoting the ability to differentiate detail).

My results:

255, 255, 255 - appeared paper white with no discernible tone, as it should

254, 254, 254 - also appeared paper white with no discernible tone

253, 253, 253 - the very slightest amount of tone was visible under light and if you looked carefully you could make out the square

252, 252, 252 - this was the first patch you could see with a quick but directed look

251, 251, 251 - and lower were pretty straightforward to see and the differences between each were evident, ie 251, 251, 251 could fairly easily discerned from 250, 250, 250 and so on

Is this helpful information??  Maybe not groundbreaking , but I think it is helpful,  Now I know that the brightest level in an image where I still want some ink and not paper white should be 251, 251, 251 or 252, 252, 252.  Many books have advocated 248, 248, 248....but I think it helps to know how your particular printer acts and what it can do with the lighter tomes.  Of course, I believe the results might only apply to the particular paper and profile that you are testing, but nonetheless I think this is useful information to have.

I am using an Epson 7900 and would be interested in what types of results people get with other printers and if this is felt to be a worthwhile endeavor.