OBC functionality in iProfiler is VERY BADLY programmed! how to bypass?

[Robert Ardill]

Because I don't have access to non-OBA inkjet paper. I'm only using Epson Ultra Prem Glossy with OBA which didn't change the look that much as evident in the photo of the white rose print demo I posted earlier.

If you're suggesting I do the same test with a print of an image with a wide range of colors on the same Epson paper viewed under the same variety of lights as in the photo, that I can do. I do have to wait for overcast light which according to local weather forecast may be tomorrow. I don't want to view under lights where there is a full blue canopy sky from a bright sunny day.

But I was hoping someone would have another brand of OBA paper where it acted on the color differently than the Epson viewing under a variety of lights. It seems so far from folk's responses on this thread their experiences are different from what I depicted in the photo demo suggesting not all OBAs are alike in this regard.

Hi Tim,

Yes, if you could photograph the image with high UV/ low UV so that we can compare them that would be very useful.  How would you set up the test?  It would seem difficult to me to take a photograph of two images with very different illuminants for comparison purposes, as the color of the light will be completely different.

Perhaps the test we should be looking at is either:
- photograph the image under the lamp, then put a UV filter over the lamp and take the photograph again, with exactly the same settings on the camera
- photograph the image under the lamp, then add UV with a blacklight torch and take the photograph again, with exactly the same settings on the camera

That way the only difference between the photos would be the UV.

What do you think?

Robert

[Tim Lookingbill]

Hi Tim,

Yes, if you could photograph the image with high UV/ low UV so that we can compare them that would be very useful.  How would you set up the test?  It would seem difficult to me to take a photograph of two images with very different illuminants for comparison purposes, as the color of the light will be completely different.

Perhaps the test we should be looking at is either:
- photograph the image under the lamp, then put a UV filter over the lamp and take the photograph again, with exactly the same settings on the camera
- photograph the image under the lamp, then add UV with a blacklight torch and take the photograph again, with exactly the same settings on the camera

That way the only difference between the photos would be the UV.

What do you think?

Robert

I disagree with the what appears to be your setup for unnecessary meticulousness for a real world demonstration of how a print will appear on OBA paper viewed under a wide range of lighting.

My previous photo of the white rose demonstrated how CMYK inkjet neutrals blend into the bright white of the OBA paper appear unaffected by the OBA viewed under these lights which is the reason I chose the white rose image. If OBA's affected perception of even neutral mixes of CMYK inkjet ink it would've shown up, but it didn't.

But a full color image having mostly primaries, warm earthen and cool pastel tones might show whether the OBA's shift the hues in these colors which I doubt since it didn't affect neutral CMYK which lays down less ink to allow more of the OBA paper white to show through.

Of course maybe a particular full saturation lay down of printed yellow on top of the OBA white might induce some spectral reflectance distortion under different lights. But then there's the other problem in determining whether the holes in the spectrum of lighting (CFL's) would be causing this where the yellow may appear a bit greenish. Is it the OBA's doing this or the light or a combination of both?

[Robert Ardill]

My previous photo of the white rose demonstrated how CMYK inkjet neutrals blend into the bright white of the OBA paper appear unaffected by the OBA viewed under these lights which is the reason I chose the white rose image. If OBA's affected perception of even neutral mixes of CMYK inkjet ink it would've shown up, but it didn't.

Tim, I went back over the topic to have a look at your rose image and I think you forgot to include it in your post.  Could you do it now, so I can see what you're getting at?

Robert

[Paul Gessler]

Tim, I went back over the topic to have a look at your rose image and I think you forgot to include it in your post.  Could you do it now, so I can see what you're getting at?

Robert, it's attached to Reply #46 of this thread.

[Robert Ardill]

Robert, it's attached to Reply #46 of this thread.

I can't see it Tim ...

Out of interest, I've taken a few M1/M2 spot measurements using i1Profiler:

Copier paper gives:
  M1 Lab readings of 92, 2.5,-9.7
  M2 Lab readings of 91,0.6,-3.8

Canson Baryta gives:
  M1 Lab readings of 98, 0.2,-1.3
  M2 Lab readings of 98,-0.4, 1.1

Canson PhotoHiGloss gives:
  M1 Lab readings of 95, 0.6,-6.4
  M2 Lab readings of 95,-1.1, 0.3

Permajet Oyster gives:
  M1 Lab readings of 95, 1.8,-14.8
  M2 Lab readings of 94,-1.1,-1.9

This pretty much confirms the plots I posted further up: the Baryta has very low OBAs, but the PhotoHiGloss has quite a bit ... and the Permajet Oyster is through the roof (not a paper one should ever use!).  Interestingly, the Baryta has a very high L value, so even though it has very little OBAs it's a very bright paper.

I also tested some papers like the Platine which are claimed to have no OBAs and the tests concur.

Robert

[Tim Lookingbill]

Robert, you say you can't see the image I posted? Or you can't see the results I was talking about in the image?

If you can't see the image at all, then you may need to use another browser or set your preferences to allow attachments or ask the administrator of these forums what setting in your LuLa profile turns on viewing or allows attachments.

I've never had a problem viewing images uploaded from anyone in this forum going on several years.

[Stefan Ohlsson]

Robert, you say you can't see the image I posted? Or you can't see the results I was talking about in the image?

If you can't see the image at all, then you may need to use another browser or set your preferences to allow attachments or ask the administrator of these forums what setting in your LuLa profile turns on viewing or allows attachments.

I've never had a problem viewing images uploaded from anyone in this forum going on several years.

It would been a better test if you had included a light gray area and white balanced your images on that area. As our vision adapt to the ambient light conditions, we will see a gray area as gray. 

[Robert Ardill]

Robert, you say you can't see the image I posted? 

I couldn't see the image at all.  I've gone in and out of my preferences and even though I changed nothing I can now see the attachment!  Maybe a kind administrator fixed it while I was not watching

It would been a better test if you had included a light gray area and white balanced your images on that area. As our vision adapt to the ambient light conditions, we will see a gray area as gray. 

Yes, I agree.  A gray card & white balancing is really needed.  The overcast sun images do seem to show blueness from OBAs, but that could just be a white-balance problem.

Robert

[Ernst Dinkla]

Hi Tim,

Yes, if you could photograph the image with high UV/ low UV so that we can compare them that would be very useful.  How would you set up the test?  It would seem difficult to me to take a photograph of two images with very different illuminants for comparison purposes, as the color of the light will be completely different.

Perhaps the test we should be looking at is either:
- photograph the image under the lamp, then put a UV filter over the lamp and take the photograph again, with exactly the same settings on the camera
- photograph the image under the lamp, then add UV with a blacklight torch and take the photograph again, with exactly the same settings on the camera

That way the only difference between the photos would be the UV.

What do you think?

Robert

Printer color mode, application CM. Make a B&W "real world" print on a high OBA content paper that shows the grey tone range without hue deviations from paper white to black. Say for the Solux "D50" with the UV-cut filter condition. Will be difficult enough BTW with the usual warm carbon black ink. Then do the same with OBC for the normal Solux "D50" condition. There is no need to put the two samples next to one another in both light conditions, the B&W print will have enough reference in the total tone range. The Permajet Oyster is a high OBA content paper, one from the Mitsubishi stable most likely. Try the same with a paper without or with little OBA content. Way more color constancy in changing light conditions. With or without OBC, a B&W print on a paper with high OBA content depends much more on color constancy in the illumination.

For OBA free papers there is in my experience something else happening too in B&W prints; the higher the white reflection of a paper is, the more the illumination light color dominates, which still affects the ink mixes but less the paper white. OBA free papers with high light reflection tend to be more neutral. With lower white reflection the paper "white" color is in competition with the color of the illumination light and can create more color constancy for changing light conditions. Eyes should adapt, they do more in color prints with a white or grey reference, in B&W the total tone range is the reference.


Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2014 update, 700+ inkjet media white spectral plots

[Robert Ardill]

Printer color mode, application CM. Make a B&W "real world" print on a high OBA content paper that shows the grey tone range without hue deviations from paper white to black. Say for the Solux "D50" with the UV-cut filter condition. Will be difficult enough BTW with the usual warm carbon black ink. Then do the same with OBC for the normal Solux "D50" condition. There is no need to put the two samples next to one another in both light conditions, the B&W print will have enough reference in the total tone range. The Permajet Oyster is a high OBA content paper, one from the Mitsubishi stable most likely. Try the same with a paper without or with little OBA content. Way more color constancy in changing light conditions. With or without OBC, a B&W print on a paper with high OBA content depends much more on color constancy in the illumination.

For OBA free papers there is in my experience something else happening too in B&W prints; the higher the white reflection of a paper is, the more the illumination light color dominates, which still affects the ink mixes but less the paper white. OBA free papers with high light reflection tend to be more neutral. With lower white reflection the paper "white" color is in competition with the color of the illumination light and can create more color constancy for changing light conditions. Eyes should adapt, they do more in color prints with a white or grey reference, in B&W the total tone range is the reference.


Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2014 update, 700+ inkjet media white spectral plots

Hi Ernst,

Thanks for the link and suggestions.  Here is a test on the (horrible!) Permajet Oyster under slightly cloudy daylight and under Solux 4700K.  As you can see the Solux has very little UV (it's SPD is quite smooth, so the paper is indicating some UV, but nothing compared to sunlight).

The paper seems to have some sort of filter for blue light under 420nm or so (the Solux does show a reasonable amount of blue at 400nm).

I can't see OBC in any way being able to compensate for this sort of difference!  Really, the best approach is to use very low or zero OBA paper and profile for the target illuminant if at all possible.

Robert

[Tim Lookingbill]

It would been a better test if you had included a light gray area and white balanced your images on that area. As our vision adapt to the ambient light conditions, we will see a gray area as gray.  

Apparently you underestimate my skill at editing and seeing what's right next to my display. I've been doing it for quite a long time. I made it look as it appears to me.

Also you're premise and logic indicates we can't trust our eyes and if that's the case then we can't trust whether OBAs affect the aesthetic appearance of a color print so there's no point measuring for it since we won't see it due to the fact we can't trust what we see.

That's what you get with circular logic. You can't deny the fact we humans rely on functionality and not just theory and/or some spectro measurement. We don't make or appreciate the aesthetics of a print derived and defined from spectrophotometry.

Posting my image is being disregarded and not even looked at anyway since this thread has gotten over 5000 views and my OBA image sample has gotten 12 views.

[Stefan Ohlsson]

Apparently you underestimate my skill at editing and seeing what's right next to my display. I've been doing it for quite a long time. I made it look as it appears to me.

Also you're premise and logic indicates we can't trust our eyes and if that's the case then we can't trust whether OBAs affect the aesthetic appearance of a color print so there's no point measuring for it since we won't see it due to the fact we can't trust what we see.

I don't underestimate anything. I don't know you, haven't seen any work from you. I'm just describing the way that I have done a similar test. And I suggested that you used a gray card without any OBA, as a Passport. And of course we can't trust our eyes, as our colour perception adapts to the lighting condition in a split millisecond.

When you do a test you try to find a way to keep all variables constant, except for the subject that you are evaluating. In this test I presumed that you wanted to see only how the OBA content in different papers affected the colours under light with high or low UV content.

[Robert Ardill]

Apparently you underestimate my skill at editing and seeing what's right next to my display. I've been doing it for quite a long time. I made it look as it appears to me.

Also you're premise and logic indicates we can't trust our eyes and if that's the case then we can't trust whether OBAs affect the aesthetic appearance of a color print so there's no point measuring for it since we won't see it due to the fact we can't trust what we see.

That's what you get with circular logic. You can't deny the fact we humans rely on functionality and not just theory and/or some spectro measurement. We don't make or appreciate the aesthetics of a print derived and defined from spectrophotometry.

Posting my image is being disregarded and not even looked at anyway since this thread has gotten over 5000 views and my OBA image sample has gotten 12 views.

Yep, I think that's a valid point.  I try to have some paper white in the image, either as part of the image or as a border, and that does make a real difference to the qualitative impression, I think.  Today, for example, I had a customer who thought a framed print that had a white border (the paper) looked much better than the same print, in the same frame, but with a mat instead of the paper border.  Things like that can have so much bigger an impact than the usually very minor color shifts due to OBAs (especially if one uses papers with no OBAs  ).  

Still, what I find is that I always learn something from these discussions ... in the case of this one, I think I've a better understanding of the papers I use than I did before; and I understand a bit better the reasons behind my dislike for the papers that I didn't like.  It hasn't changed anything really as I will continue to use the papers I like and continue not to use the papers I didn't like, but what it does mean is that I will have a better idea of what to look for and what to avoid when I next need a new paper.

Having said that ... I'm a bit surprised that your images (which I eventually did manage to view are shown as you saw them because I think your eyes would have compensated much more for the different lights.  If your eyes did not, and if this is really what you saw, then I would suggest you get a new paper because the color shifts would seem unacceptable to me.  Even with a paper pickled with OBAs like the Permajet Oyster, it's surprising the extent to which the eye adapts to different illuminants.

Robert

[Alan Goldhammer]

 Even with a paper pickled with OBAs like the Permajet Oyster, it's surprising the extent to which the eye adapts to different illuminants.

Robert

A single print without any comparator will always look fine assuming the image is processed OK.  The eye adapts to what it sees.  Where we begin to see vast differences is when the same image printed on different papers is compared.  The eye/brain axis responds differently and of course personal preferences will always come into play here.  One can print on matte papers with perfectly acceptable and sometimes pleasing results even though the paper gamut is not as large as a gloss paper.  The eye adapts to the color/monochrome shadings.  The same thing goes for different illuminants.

[Tim Lookingbill]

I don't underestimate anything. I don't know you, haven't seen any work from you. I'm just describing the way that I have done a similar test. And I suggested that you used a gray card without any OBA, as a Passport. And of course we can't trust our eyes, as our colour perception adapts to the lighting condition in a split millisecond.

When you do a test you try to find a way to keep all variables constant, except for the subject that you are evaluating. In this test I presumed that you wanted to see only how the OBA content in different papers affected the colours under light with high or low UV content.

I posted what I saw. It's that simple. This is not a scientific endeavor. We don't create prints by subjecting it to scientific scrutiny. If you want to turn it into a science project, knock yourself out. A digital camera is not a precise scientific instrument and image reproduction on paper can't be tested using exacting science. If you can't understand that, then I'm not interested in what you have to offer in moving this thread forward.

None of the info in this thread has helped me one bit.

[Stefan Ohlsson]

None of the info in this thread has helped me one bit.

OK, we hear what you are saying. I can say that constructive advise is something that helped me to improve my photography and that forums like LuLa has accelerated this. But if you don't understand the suggestions and call that scientific scrutiny I think that a. you don't understand what scientific scrutiny requires b. you don't understand the simple suggestions that we have placed to improve your interesting test. 

[Robert Ardill]

A single print without any comparator will always look fine assuming the image is processed OK.  The eye adapts to what it sees. 

I do agree to some extent.  However what got me involved in this thread is that I printed a photograph of some poppies that I had painted (below) and looking at it under a 6500K fluorescent it really didn't look right - there was much too much blue in the magentas (to my mind).  I then looked at the print under a warmer light and I thought it looked fine.  The paper had no OBAs.

I find that images that have few fairly saturated colors tend to look better under particular illuminants.  I know that the theory is that chromatic adaptation should take care of the illuminant, given a few seconds for the eye to adjust, but I don't personally buy in to that totally.  It could be, for example, that the spikes in the fluorescent were hitting the colors in the image at just the wrong points.  Perhaps chromatic adaptation works best when the shape of the illuminant SPDs is smooth and the only difference is the color balance.

Robert

[Stefan Ohlsson]

I do agree to some extent.  However what got me involved in this thread is that I printed a photograph of some poppies that I had painted (below) and looking at it under a 6500K fluorescent it really didn't look right - there was much too much blue in the magentas (to my mind).  I then looked at the print under a warmer light and I thought it looked fine.  The paper had no OBAs.


Robert

This is another problem, more like metameric failure. Paintings, especially aquarelles are a pain in ... to reproduce correctly. It takes a lot of tweaking to get it right, and you have to know under which light conditions the final print is going to be seen under. The different profiles in ImagePrint is a big help here.

[Tim Lookingbill]

...I find that images that have few fairly saturated colors tend to look better under particular illuminants.  I know that the theory is that chromatic adaptation should take care of the illuminant, given a few seconds for the eye to adjust, but I don't personally buy in to that totally.  It could be, for example, that the spikes in the fluorescent were hitting the colors in the image at just the wrong points.  Perhaps chromatic adaptation works best when the shape of the illuminant SPDs is smooth and the only difference is the color balance.

Robert

Really nice painting, Robert. Didn't know you had this talent.

That was helpful of you posting the photo sample of an image reproduced on non-OBA paper. Was wondering whether that paper looks less neutral white (off white/slightly yellowish) placing it next to paper with OBA (overlap comparison) and whether the two papers will exhibit varying hue shifts under different lights.

The Epson Ultra Prem Glossy with OBAs exhibited a more pinkish/violet blue (over cyan blue) in the overcast light on my front porch (seen in my sample photo) more than I'ld expected. It was almost a shock to see it shift hue so severely right after opening my front door to see the neutral bright white I'ld adapted to under home viewing light which is a mix of a bit of open window light filter by white plastic blinds and 5000K daylight LED and fluorescent.

As for your painting looking odd under 6500K fluorescent, I'ld have to go with the spiky spectra as the cause. I haven't come across any 6500K fluorescent that made anything look good. Out of all the CFL's I've tried Alzo 5500K CRI 95 is the best so far, but it makes saturated cadmium yellows look lemon yellow (increase in cyan).

And for flotubes a combination of T8 18in. 5000K Philips Natural Sunshine and 5000K GE Chroma 50s (Sunshine labeled) keeps color distortion to a minimum but do give off a slight greenish warmth after long edits adapting to a 6500K neutral calibrated display.

[Robert Ardill]

That was helpful of you posting the photo sample of an image reproduced on non-OBA paper. Was wondering whether that paper looks less neutral white (off white/slightly yellowish) placing it next to paper with OBA (overlap comparison) and whether the two papers will exhibit varying hue shifts under different lights.

The Epson Ultra Prem Glossy with OBAs exhibited a more pinkish/violet blue (over cyan blue) in the overcast light on my front porch (seen in my sample photo) more than I'ld expected. It was almost a shock to see it shift hue so severely right after opening my front door to see the neutral bright white I'ld adapted to under home viewing light which is a mix of a bit of open window light filter by white plastic blinds and 5000K daylight LED and fluorescent.

As for your painting looking odd under 6500K fluorescent, I'ld have to go with the spiky spectra as the cause. I haven't come across any 6500K fluorescent that made anything look good. Out of all the CFL's I've tried Alzo 5500K CRI 95 is the best so far, but it makes saturated cadmium yellows look lemon yellow (increase in cyan).

And for flotubes a combination of T8 18in. 5000K Philips Natural Sunshine and 5000K GE Chroma 50s (Sunshine labeled) keeps color distortion to a minimum but do give off a slight greenish warmth after long edits adapting to a 6500K neutral calibrated display.

Hi Tim,

Here's a comparison between 4 papers, two with no OBAs, one with just a bit and one with quite a lot, taken first under cloudy sky then under Solux.  There's not much to it, but visually there's no color shift on the papers without (or with little) OBAs, whereas the Photo HiGloss has a noticeable shift towards magenta/blue under the sky.  I've included Lab values, but I'm not sure that they help much as I hand-held the Solux lamp and the illumination wasn't even over the paper.

Still, you can see quite clearly how much whiter/bluer the HiGloss paper is compared to the others.

When you say a combination of the Philips and GE tubes, do you mean to use both together?

Robert