Matching print to screen with A Solux MR16 4700k. What distance from print?

[Bill Koenig]

With a Solux MR16 36 degree spread. The following is from there web site.
 At two feet brightness 3,741 Lux
 At ten feet  brightness  150 Lux

OK, with that info, how far should the light be from the print?

[Mark D Segal]

This is a really good question and one that I find somewhat perplexing, because I've not come across a definitive answer to it. It is not only the distance but also the angle at which the light strikes the paper. I use the same bulbs. I have a string of six of them angled in different ways on a track on the ceiling of my work space. That would put the bulbs about 5 or 6 feet away from the images. It has become my benchmark for assessing print luminance. Then I have my display calibrated at about 110 cd/m2, which in a dimly lit environment, pretty well mimics (under soft-proofing) what I can expect from Ilford Gold Fibre Silk seen in that manner. I've tested this by looking at the prints with daylight coming in the windows as well as under bright-ish incandescent lighting, such a 500W halogen torchiere in the living-room, and it all seems to work. So, a number of variables to consider - distance, angle, kind of paper, display calibration, display environment, etc. While workable in my environment, I'm not convinced this is a be-all/end-all answer to your question.

[Bill Koenig]

This is a really good question and one that I find somewhat perplexing, because I've not come across a definitive answer to it. It is not only the distance but also the angle at which the light strikes the paper. I use the same bulbs. I have a string of six of them angled in different ways on a track on the ceiling of my work space. That would put the bulbs about 5 or 6 feet away from the images. It has become my benchmark for assessing print luminance. Then I have my display calibrated at about 110 cd/m2, which in a dimly lit environment, pretty well mimics (under soft-proofing) what I can expect from Ilford Gold Fibre Silk seen in that manner. I've tested this by looking at the prints with daylight coming in the windows as well as under bright-ish incandescent lighting, such a 500W halogen torchiere in the living-room, and it all seems to work. So, a number of variables to consider - distance, angle, kind of paper, display calibration, display environment, etc. While workable in my environment, I'm not convinced this is a be-all/end-all answer to your question.

Mark, thanks for the quick reply.

I'm also using Ilford Gold Fibre Silk. My old 21" Sony CRT is set to 95 cd/m2, and in a dimly lit room I'm getting a great match, but as I moved the print in and out of the light, this question of distance is in fact quite perplexing, and I can't remember seeing any numbers, (just use a Solux lamp) is all I've seen in regards screen to print match.
Moving the print in and out of the light, I can get a match (and a distance) but what does that mean?
I could dust off my old light meter and measure the light at different distance's, but I still need a starting point to set my light meter.
As to the angle, I guess when there's no glare, that's the correct angle.

BTW, I'm only using a single lamp.





 

[walter.sk]

It seems to me that a good starting point would be:

1) Have a satisfactorily calibrated monitor (which you  do already.)
2) Bring up and soft proof your test image.
3) Use your print of that image, assuming that it looks right under daylight or other viewing source, and place the Solux light at whatever distance makes the print look closest to your softproofed image on the display.
4) Measure and mark the placement of the Solux lamp so that you can repeat it reasonably closely.

After that, go through Andrew Rodney's "Why is my print too dark?" tutorial on this website to fine tune your settings.

[Alan Goldhammer]

Mark, thanks for the quick reply.

I'm also using Ilford Gold Fibre Silk. My old 21" Sony CRT is set to 95 cd/m2, and in a dimly lit room I'm getting a great match, but as I moved the print in and out of the light, this question of distance is in fact quite perplexing, and I can't remember seeing any numbers, (just use a Solux lamp) is all I've seen in regards screen to print match.
Moving the print in and out of the light, I can get a match (and a distance) but what does that mean?
I could dust off my old light meter and measure the light at different distance's, but I still need a starting point to set my light meter.
As to the angle, I guess when there's no glare, that's the correct angle.

BTW, I'm only using a single lamp.

I could give you the funny answer, "far enough away to match your monitor!"  I have the same set up as you a single lamp on a gooseneck right next to my printer.  I made a small clipboard stand that I can put the print on which is about 3 feet away (any further and I don't get even illumination).  This seems to work well with IGFS and gives a decent match.

[eronald]

It seems to me that a good starting point would be:

1) Have a satisfactorily calibrated monitor (which you  do already.)
2) Bring up and soft proof your test image.
3) Use your print of that image, assuming that it looks right under daylight or other viewing source, and place the Solux light at whatever distance makes the print look closest to your softproofed image on the display.
4) Measure and mark the placement of the Solux lamp so that you can repeat it reasonably closely.

After that, go through Andrew Rodney's "Why is my print too dark?" tutorial on this website to fine tune your settings.

I have a different point of view: If you have a profiled printer, either you can easily figure out what the next print is going to look like, or you need to switch profile settings or profiling software. Print and screen are not going to look alike, the function of the screen is to let you predict what the print will be.

Art printing is not proofing. Art printing is about making prints which will make you or the client happy, reproducing the feel of what is on the screen; focusing a Solux light 8 inches away from a print may bring the print color out in a way that reproduces the self-luminous effects of a screen, but it won't mirror most real-life viewing conditions. If the client really expects screen-perception, maybe she should mount a display on the wall, use a projector in a dark room or a print illuminated in a low ambience by a spotlight (very popular in museums) or use film mounted on a lightbox.

And yes, by the way, I have found that changing profiles on the display often makes issues go away. There are subjective decisions built into every screen profiler, and if you are unhappy with them the first thing to do is switch the profiler you use into advanced mode and play with the settings. There are also viewing condition assumptions built into print profilers, but we won't go there today

Oh, and by the way, print size has a VERY large role in the subjective perception of brightness and color, print something *fairly dark* at A4 and at A2, have a look at it, and you'll suddenly see the colors and texture in the A2 print come alive for you; even A3 is very different from A4. The same effect affects screens, so previewing on that *huge, bright* display is not such a good idea. Printing larger usually does wonders for your colors and shadows.

I have spent hours discussing these issues with one of my color scientist friends, because they still bite me in the butt regularly.

I'm sure Andrew will have something to say too, my opinion is that he exonerated the software a bit too quickly in what he wrote. Some of the software I've seen,is quite good with some settings and yucky at a different setting, it's not an exact science. In my book, you get decent software first, *then* you adjust your expectations of print matches screen, within the limits of your hardware. Bad software (or hardware) is really bad only if you cannot adjust your expectations to match its effect.

Please read all the above remarks in relation to art printing only; proofing has very different constraints.

Edmund

PS. If you are trying to profile a MacBook Pro, have a look at my blog, what I do is not pretty, but it seems to work.

[Ernst Dinkla]

Oh, and by the way, print size has a VERY large role in the subjective perception of brightness and color, print something *fairly dark* at A4 and at A2, have a look at it, and you'll suddenly see the colors and texture in the A2 print come alive for you; even A3 is very different from A4. The same effect affects screens, so previewing on that *huge, bright* display is not such a good idea. Printing larger usually does wonders for your colors and shadows.

A topic for another thread but this may be interesting to read:
http://art-si.org/PDFs/Processing/MahdiNezamabadi_PhD2008.pdf

With that in mind I asked the developer of Qimage whether algorithms could be added to compensate the effect which is more complicated than just the size relation. I think he found it a bit over the top but you never know next time it is added to the software without any comment.

met vriendelijke groeten, Ernst

New: Spectral plots of +250 inkjet papers:

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm