# Calibration for printing



## adamhiram (Sep 28, 2018)

Please pardon the lengthy post - I think my questions are fairly simple, but first a bit of background information.

I edit all of my photos on a calibrated display in a room with moderately low ambient light and very limited direct sunlight, so I am relatively confident my images will look the way I want on other calibrated displays.  Printing is another story though, and I’ve gone through various printing services before finding one I liked.  Some came out okay with no additional work, others required working with their printer ICC profiles to tweak images to get them to print correctly.  And some, of course, just never seem to come out right.

I have been happy with prints from Mpix for a few years, and don’t seem to have these issues with them most of the time.  A friend recommended leaving color correction on in case there were any color matching issues with their printers, and for the most part, my prints from them have been beautiful.  There were 2 exceptions though.

I noticed the first issue when I printed some very high key photos, such as an image containing snow or that was strongly backlit - sometimes to the point of having highlights being completely blown out (intentionally).  Those prints seemed to come back underexposed, which I assumed was their color correction process trying to correct for the blown out highlights.  They were always willing to reprint these at no cost, and I was happy with the results.

The other issue that got me thinking was when some very low key photos also came out too dark.  One was a studio portrait with a darker background, that came out nearly pure black in the print.  The other was a group photo with several individuals with darker complexions, whose faces had all but disappeared in the print.  If the high key photos were underexposed due to the printing service's exposure compensation, surely the low key photos would have been overexposed as a result, instead of also being underexposed.

Here is where it gets interesting.  I reached out to Mpix support, and they were able to tell me what adjustments had been made to each image before printing.  For all of them, it was a slight increase in brightness.  This suggests that all images I’ve been sending to them likely start out as slightly underexposed, and I probably just didn’t notice it except in extreme examples.

We also talked about monitor calibration, and it turns out the target values I am calibrating to are different from the ones they use and recommend.  Where I get confused is that my brightness and white balance targets are the default values used by my Spyder 4 Pro, and can’t be manually changed.  I can still calibrate to different values, but it takes some trial and error.  This leaves me wondering if I should change my calibration to match their recommended values, or just have a separate export preset for any images I send to them for printing.

Here are the target settings I calibrate to:

Ambient light: Moderately low
Gamma: 2.2
Brightness: 120 cd/m^2
White point: 5800K
And here are the target settings they recommend:

Gamma: 2.2
Luminance: 100 cd/m^2
White point: 5000K

In short, my monitor is calibrated to be about 20% brighter than theirs (assuming luminance is a linear scale), and my white point is a bit warmer than theirs.  This should mean that on their end, my images should be a bit too dark, and possibly too cool.  I haven’t noticed any white balance issues, but they definitely seem to be coming out too dark.

Questions:

Should I change my calibration targets to match the ones they recommended, or will that result in my images being overexposed everywhere else, since I have to assume most people that calibrate their displays use the default or vendor recommended settings?
Can I fix my issue by simply adding a 20% boost to exposure (Exposure + 0.2) when exporting to print through them?


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## adamhiram (Oct 8, 2018)

Bump...  Anyone?

Is this just a matter of my monitor being calibrated too bright (compared to what they expect), so my images appear too dark on their end?  They provided an ICC printer profile to use for proofing, but if the issue is I am just editing on too bright of a monitor (again, just in comparison to theirs), it would seem the fix is to just bump the exposure by +0.2 before sending to them to print.


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## smoke665 (Oct 8, 2018)

@adamhiram Maybe it isn't your problem. I've been very happy with Nations, price and delivery is great,  only a couple of issue which they went above and beyond too correct, not only reprinting the photo, but sending it next day air without me even asking. Let me say I have NEVER used their color correction, and have always had consistent WYSIG results. So I was reluctant to try Mpix, but my daughter gave me a $50 gift certificate so what the heck. What a PITA that was. The first test order came back okay on color, which tempted me to try another, that came back horrible color. Because I didn't use their "color correction" they wouldn't replace. When I asked why my first order came back fine, without color correction, but the second in the set came back wonky, the CS became rude and obnoxious. Long story short, I reordered them from Nations (without correction), and they came back great as always. Just my experience, but I won't ever do business with them again.


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## adamhiram (Oct 9, 2018)

smoke665 said:


> I've been very happy with Nations, price and delivery is great, only a couple of issue which they went above and beyond too correct, not only reprinting the photo, but sending it next day air without me even asking. Let me say I have NEVER used their color correction, and have always had consistent WYSIG results.


Thank you for the recommendation, I think I will order some test prints and see how they compare.  I understand that to get full control over the output, I need to use soft proofing with their ICC profile, but I've always been under the impression that photos edited on a properly calibrated display should result in prints pretty close to what I sent them without much extra work.  My experiences with Mpix over the years have been pretty positive, especially with their customer service willing to make things right, but they never seem to be able to provide a long-term fix.  Bonus points that Nations uses lustre paper instead of charging extra for a lustre coating - that always seemed strange to me.

Thanks, and I will let you know how I make out!


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## smoke665 (Oct 9, 2018)

Not only the difference in the paper, but I think Nations may be a little cheaper overall, especially if you hit one of their sale deals. I calibrate my monitor monthly with X-rite and never used their proprietary profile. I've never been disappointed. I told you wrong on color correction, I did try it once, and frankly couldn't tell any difference.


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## ac12 (Oct 10, 2018)

In theory, if you use their printer profile, you should be able to send them a file that they do ZERO manipulation to.
That is the idea of using their printer profile.

If they are doing color correction, then why even bother with monitor and printer calibration.  Because you don't know what their color correction will do to the image that you send to them.

BTW, the color of your shirt could also affect how the monitor looks, if any light reflects off your shirt onto the monitor.


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## smoke665 (Oct 11, 2018)

ac12 said:


> , the color of your shirt could also affect how the monitor looks, if any light reflects off your shirt onto the monitor.



Good point. The color/intensity of the ambient light in the room can as well, especially if it changes from your last screen calibration. I came across something else recently, now that my vision is better. Windows 10 has a nighttime viewing setting that will automatically dim the monitor for a preset time if checked. Prior to the cataract surgery it wasn't noticeable, now I see a big difference. I had to uncheck that feature.


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## ac12 (Oct 11, 2018)

smoke665 said:


> ac12 said:
> 
> 
> > , the color of your shirt could also affect how the monitor looks, if any light reflects off your shirt onto the monitor.
> ...



Not only does it dim the monitor, but the color shifts to red/orange.
Because of that, I cannot view photos when "night light" goes on.


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## smoke665 (Oct 11, 2018)

ac12 said:


> but the color shifts to red/orange.



That's right, I'd forgotten it bypasses your profile and warms the screen.


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## adamhiram (Oct 11, 2018)

Excellent tips guys, thank you.  However in my case there aren't any issues with colors; prints are just coming out too dark, and their recommendation is to calibrate my monitor's brightness to a dimmer target setting so when I edit photos they end up brighter, and therefor print brighter.  It makes sense, but also seems like a bit of a backwards solution.  I ordered some test prints from Nations with color correction turned off, so we'll see how those turn out.


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## SquarePeg (Oct 11, 2018)

adamhiram said:


> Excellent tips guys, thank you.  However in my case there aren't any issues with colors; prints are just coming out too dark, and their recommendation is to calibrate my monitor's brightness to a dimmer target setting so when I edit photos they end up brighter, and therefor print brighter.  It makes sense, but also seems like a bit of a backwards solution.  I ordered some test prints from Nations with color correction turned off, so we'll see how those turn out.



Following.  Please let us know your results.


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## adamhiram (Oct 15, 2018)

I received my prints from Nations today, and they were... different.  Better in some ways, but had some other minor issues.  I compared them to the prints I got from Mpix, both color corrected and uncorrected, and then with the original digital files.  Soft proofing showed some subtle differences, but didn't really explain everything.

The new prints from Nations were brighter than the uncorrected ones from Mpix, and about the same as the corrected ones.  However they were still not as bright as I would have expected.  It sounds like calibrating my monitor a little dimmer might help here.
I definitely noticed more contrast in the Nations prints, especially in darker areas that got a bit muddled in the Mpix ones, so that's a win.
Some of the colors were a bit off, which wasn't represented in soft proofing.  The most noticeable was that yellows had a visible orange tint to them.  Greens seemed a bit off too, being darker and more brownish, which may be a side effect of the yellows being off.
One test image with a neutral gray background seemed to have a slight pinkish tint to it - no clue where that came from.  I wasn't too obvious unless I was comparing 2 images side by side, but it still shouldn't be there.
Lastly, most prints seemed a little bit warmer, although this was reflected in soft proofing, so no concerns there.
I think my next steps are to reach out to Nations and see if they can provide some feedback on the color casts, and possibly calibrate my monitor to a dimmer setting per Mpix recommendations.  After some research, it sounds like their recommended setting of 100 cd/m2 may be more appropriate than the 120 cd/m2 setting I've been using for a dimly lit office.


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## ac12 (Oct 15, 2018)

Did you get the printer profile for the Nations printer?


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## adamhiram (Oct 16, 2018)

ac12 said:


> Did you get the printer profile for the Nations printer?


Yes, they provide their ICC profiles and detailed instructions for Lightroom here.  I only use them for soft proofing, as described in their instructions, to ensure there aren’t any differences I can’t live with.  In several images, yellows were noticeably more saturated with proofing turned on, but that doesn’t account for the orange cast.  In one example, all of the colors look correct except for a light yellow shirt that looks almost peach.  I will try to post some examples soon.


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## smoke665 (Oct 16, 2018)

adamhiram said:


> possibly calibrate my monitor to a dimmer setting



I don't recall if you are using Windows, but if so have you checked your settings on display. The new 10 thinks it knows what you want better then you do. There are some settings that bypass your profile, and some extra steps in Advanced settings to force it to always use it.

Did you go with the Lustre paper and the Linen texture?

Also the profiles supplied by Nations say that the white point is based on the paper or substrate. So it requires different profiles. I'm curious if there's any difference in proofing in Lr vs PS?


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## adamhiram (Oct 16, 2018)

smoke665 said:


> I don't recall if you are using Windows, but if so have you checked your settings on display.


I am on a Mac, but it has similar settings.  I have "Night shift" and "Automatically adjust brightness" disabled.



smoke665 said:


> Did you go with the Lustre paper and the Linen texture?


Lustre paper (and did soft proofing with the Lustre ICC profile).  No linen texture - after trying to scan many old photos on texture paper, I learned to skip anything that will make prints difficult to scan in the future, should the need arise.



smoke665 said:


> I'm curious if there's any difference in proofing in Lr vs PS?


I seem to recall proofing in PS being a little more involved.  In LR, you just configure which ICC profile to use for soft proofing, and check/uncheck the soft proofing checkbox in the develop module to preview what the output will look like.


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## smoke665 (Oct 16, 2018)

adamhiram said:


> Lustre paper (and did soft proofing with the Lustre ICC profile). No linen texture - after trying to scan many old photos on texture paper, I learned to skip anything that will make prints difficult to scan in the future, should the need arise.



I was led to believe that the color of a print is reflective, and that smooth surface would produce a different view then a rough surface (linen texture). Not sure where I even came up with that. LOL



adamhiram said:


> I seem to recall proofing in PS being a little more involved



I do know the export function of Ps allows you to "embed" the color profile in the JPEG, which it is my understanding that modern browsers will look for and use that to display on the web rather then the industry sRGB.

You've really piqued my interest with this thread. I've been dissatisfied with how my images appear after they leave Lr or Ps for sometime, but to lazy to find out why. I actually took some time to research and learn the soft proof process in Lr, since I use it most anyhow. By putting the original and soft proof copy side by side in comparative view I was shocked at how much difference there really is when the image is corrected for the profile, even soft proofing for sRGB.  I am still a little confused on when to use "Perceptual" or "Relative". I understand what each does, but one video says "I always use Perceptual" and the next says "I always use Relative" Next test will be to send off some prints for comparison.


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## adamhiram (Oct 20, 2018)

I wanted to follow up with some examples of the issues I have been having and what the output looks like compared to the original images.  One thing that became very apparent is just how bad both of my scanners are, so i wound up using a setup for digitizing large items with 2 opposing softboxes and an overhead camera rig - but that's a discussion for another time.

Here is an example of the original issue I was having with Mpix.  With color correction disabled, the colors come out just fine, but the images are too dark.



20180708-DSC_8949a-compare-mpix by adamhiram, on Flickr




20171225-DSC_5103a-compare-mpix by adamhiram, on Flickr

However when I enable color correction when ordering prints from Mpix, I am usually pretty happy with the output.  My last discussion with them confirmed that the only "color correction" they are actually doing is increasing the brightness.  There are some slight differences between the original digital image and the print, but that's to be expected when printing, and nothing to be concerned about.



20180708-DSC_8831a-compare-mpix-corrected by adamhiram, on Flickr




20180610-DSC_8094a-compare-mpix-corrected by adamhiram, on Flickr

However with the prints from Nations, not only are they darker, but they also show some noticeable color casts, particularly with yellows and colors containing yellows.  Soft proofing showed some subtle differences, but definitely did not match the output.

In this one, you can see the man's shirt looks more peach than yellow, clearly showing the orange cast in the yellows.



20180708-DSC_8949a-compare-nations by adamhiram, on Flickr

Here we can see the greens have a lot more brown to them, and the yellow highights in the background are a bit orange.



20180708-DSC_8831a-compare-nations by adamhiram, on Flickr

In this one, the yellow stuffed animal looks orange, and the green shirt looks more brown.



20180610-DSC_8094a-compare-nations by adamhiram, on Flickr

Lastly, in this photo we can see the yellow glow from the chandelier on the ceiling on the top left appears orange in the print, and the young lady's blue-green shirt on the right is much more blue.



20171225-DSC_5103a-compare-nations by adamhiram, on Flickr

I still need to figure out the brightness issue, and plan to reach out to Nations for support on the color casts I am seeing, but for now it looks like Mpix is a much better choice for accurate color reproduction.


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## smoke665 (Oct 20, 2018)

@adamhiram interesting, thanks for sharing and documenting.  Couple of points.

In the first example of the man and woman from Mpix. On my monitor I'm seeing a slight color shift in he man's shirt and skin tone, but that could be the darker part you're talking about.
In the second example with color correction from Mpix, I'm seeing color shift in the red of the boy's shirt and the yellow of the duck.
In the last example of Nations, did you both soft proof and use their color correction, or did you just soft proof?
Did you try a test from Nations sending your original (less soft proof), and using their color correction??
Is it possible that you're comparing a backlit screen image to a printed image?


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## adamhiram (Oct 20, 2018)

smoke665 said:


> interesting, thanks for sharing and documenting. Couple of points.


Thank you for the great feedback!  I think the main factor that I couldn't really control for with this illustration was how to scan the prints back in to accurately show the differences.  I definitely agree with some of your observations and had to go back to the actual prints to see if those color shifts and differences were there too, or just in my scans/captures.

In the first example, the physical print doesn't show any significant color shift in the man's shirt and skin tone other than being a bit darker.  Maybe a little warmer, but much better than the print from Nations.
With the child pictures, I see slight differences in how the red shirt and yellow bird are rendered in the print too, but nothing major.  Looking at the physical prints, again it is the one from Nations that actually looks orange.
With all the Nations prints, I did soft proofing after the fact to see if their ICC profile explained the color shifts, which it mostly didn't.  I did not use their color correction, as my goal was to have photos printed exactly how I send them without someone else making those decisions.
No, I did not try their color correction.  I confirmed with Mpix that they did not edit my colors at all when I enabled color correction, just the brightness - at least for these particular photos.  I was hoping this would be the case with Nations as well.
All I can really do when comparing a backlit screen to a printed image is to look for specific colors or details in each photo and ensure both are acceptable.  I fully expect there to be some differences, but yellows shouldn't be orange, and greens shouldn't be brown.
Thanks again!


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## smoke665 (Oct 21, 2018)

@adamhiram I went through some really strange color issues over the past few months, partly software, partly hardware and partly don't have a clue. Like us part of it could be differences in hardware/software/processing at the labs. I believe you when you say Mpix told you they only change brightness in color correction but I wonder if the person you talked to really understood what they were talking about. In my case the images sent to Mpix with reddish cheek skin tones came back objectionable Orange. I do agree that your comments about the brightness and gamma of the screen have a significant effect on hue and the brightness/darkness of the final print. Just out of curiosity have you double checked your images on other devices? Lastly ambient room light on is always going to have an effect.

When you send images to the lab without soft proofing I'm assuming you are exporting as sRGB. Are you then checking that image against the original? I've noticed that if I softproof my image using LR's standard sRGB I'm seeing some shifts. The sRGB standard supports a greater diffuse white and wider gamut.

Some observations on softproofing in LR-

I'm finding in LR  "perceptual" is far more restrictive on out of gamut then "relative".
Almost none of the images I've proofed have required any adjustments to exposure, and those that did were more of a discretionary afterthought over the original.
Saturation adjustment was required to bring the images back in range. Either global, targeted, or via adjustment brush. Some of which were significant adjustments.
Generally the primary colors were the most prone to be out of gamut. I suspect that the screen brightness plays a factor in this.


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## adamhiram (Oct 21, 2018)

smoke665 said:


> I went through some really strange color issues over the past few months, partly software, partly hardware and partly don't have a clue. Like us part of it could be differences in hardware/software/processing at the labs.


The bottom line for me is that I understand that prints won't match my original images exactly, and am fine with that if it means I can just send my images to be printed without having to spend any additional time tweaking each one.  I expect to see colors that don't match perfectly, some differences in contrast and saturation, and I am generally okay with that.

I use a 27" 5k iMac for editing, which has been reviewed as a decent display for photo editing, and I re-calibrate once a month with a Spyder4Pro.  Ambient light is moderately low, with sunlight mostly blocked by a room darkening blinds, just one lamp in the corner with a 60W equiv LED bulb, and no direct light hitting the screen.  I typically check on several other devices before posting or printing anything, and I've found that a recent model iPhone or iPad with screen brightness set to auto tends to pretty accurately reflect what others will see, even if they aren't technically calibrated and tend to be on the bright side.  I export images from LR as sRGB, and never found any real differences between the exported image and the one I am working on in Lightroom.

Let me try a different approach for the brightness issue.  I still want to figure out if the root cause is that my source files that are too dark, or if I just need to bump up the brightness when using these printing services.  If the problem is on my end, I would guess it is due to my screen being calibrated too bright, which would result in my final images being too dark.  This is what Mpix support suggested, although I am using the recommended settings from my calibration tool based on the ambient light levels detected.  However I meter my strobes for any portrait work I do and rarely need to adjust the exposure for those images in post, so I would be surprised if that is the issue.

*I am interested to see if others with calibrated displays consider these images properly exposed.*

In this image, the background should have a just-visible texture of dark browns, and should not appear to be black or a dark solid color.  The man's hair should be lit just well enough that it doesn't disappear into the background.




20180708-DSC_8949a by adamhiram, on Flickr

And in this image, the background should appear to be a medium gray, with just enough fill light on the shadow (right) side to still see the texture in the child's hair.




20180610-DSC_8094a by adamhiram, on Flickr

Do you see the same exposures and details that I described, or something different?


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## smoke665 (Oct 21, 2018)

adamhiram said:


> Do you see the same exposures and details that I described, or something different?



I worked on just the first image. First let me clarify, something about TPF and other social media sites seems to crush images, so there is a slight difference between what I first see on the site, versus what I see when opened on Flickr. I used the Flickr image for comparison. On my tablet there are slight difference, but not significant from what I see on my calibrated monitor, which I would expect. When I downloaded the image into PS there was no significant between what I see on Flickr compared to the view in PS. 



adamhiram said:


> In this image, the background should have a just-visible texture of dark browns, and should not appear to be black or a dark solid color. The man's hair should be lit just well enough that it doesn't disappear into the background.



The Flickr image I'm viewing on my tablet, monitor, and in PS are as you describe.

I sampled the mans shirt, averaged the color and did are reading. Here's what it showed.



 

I sampled the forehead on the woman, averaged and here is the result. 



 

Maybe this will help if you sample your original to compare. As a footnote I tried to bring your images of the Mpix and Nations examples into PS. The color shift to red was over the top bad. So bad I didn't bother sampling. Not sure what's up with that.


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## adamhiram (Oct 21, 2018)

smoke665 said:


> The Flickr image I'm viewing on my tablet, monitor, and in PS are as you describe.


Thank you very much, I think that tells me what I really needed to know - are my source images too dark from editing on too bright of a display, or are they just printing dark.  It sounds like you were able to confirm it is likely the latter.  I will reach out to Nations this week to try their color correction, but in the meantime I may opt to just stick with Mpix + color correction.

It sounds like you were able to confirm the strong color cast on the prints, although I'm not sure if the Mpix one really has a cast or if it was how I scanned it - the print didn't show that much of a red shift.  Thank you very much, I appreciate your help in analyzing this and working through it!


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## smoke665 (Oct 21, 2018)

adamhiram said:


> It sounds like you were able to confirm the strong color cast on the prints, although I'm not sure if the Mpix one really has a cast or if it was how I scanned it - the print didn't show that much of a red shift. Thank you very much, I appreciate your help in analyzing this and working through it!



No problem as I'm watching and learning from you on this as well. Just to be clear when I talked about the examples Mpix and Nations where you showed the original, soft proof and their image, the red shift wasn't that noticeable when viewing on Flickr. It was ONLY AFTER I imported it into PS that the red color shift took place - at that point it was huge.

Something else that's fairly common is if you can determine a pattern then you can set a preset to automatically correct it. IE: all my prints are to dark = preset that bumps exposure by X amount on all prints sent to ??? I'm still not sure that even using a lab's profile will result in the exact same results given the differences in equipment.  One thing to be aware of is if you start changing monitor brightness or gamma, will that only affect the profile of that lab or will it be an across the board change which will also affect your web images?

Edit Footnote: I forgot to ask, are you soft proofing in PS or LR. I use LR because the process is much easier. Click the drop down list and go. In PS it requires more settings changes. Also, when you don't soft proof to their profile, are you just exporting as sRGB and sending the file or do you still soft proof to sRGB. LR offers two profiles, sRGB and sRGB IEC 61966-2.1. I can't remember where I read it, but it's my understanding that when there is not a specific profile embedded, labs will automatically machine match to sRGB IEC 61966-2.1. In playing around with it, I've noticed there are some subtle differences between the two.


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## adamhiram (Oct 23, 2018)

I think the differences you are seeing between Flickr and Photoshop are my fault.  Any images I export from Lightroom automatically get the sRGB profile embedded, while my PhotoShop exports don’t have any embedded profile.  I have a feeling your browser is making some (correct) assumptions about the color space, while Photoshop is probably just using whatever default color space you have configured.

Your comment on monitor brightness hits the nail on the head with my original concern.  Mpix suggested turning down my brightness, which would lead to me increasing the exposure of my images, and ultimately brighter prints from them.  However if my monitor is already calibrated to an appropriate brightness (as you indirectly confirmed earlier), the end result will be overexposed digital images, but correct prints.  Your suggestion of creating a separate preset when exporting for printing makes a lot more sense here.

I usually don’t soft proof at all, but when I do I use Lightroom since it is just a simple checkbox in the develop module, and ultimately what I use for managing images.  I export to sRGB, since that is what most labs ask for and most browsers will render to.

Ultimately, I just want my display calibrated such that my edits will look the same on any other properly calibrated displays, while also being able to get accurate output through a professional printing service without having to edit everything a 2nd time.  It doesn’t seem like that should be too much to ask!


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## smoke665 (Oct 23, 2018)

adamhiram said:


> I usually don’t soft proof at all,



And therein might be a source of some of the problems. I've also had several conversations with Nations trying to understand. There can be subtle differences between an image you export as a sRGB and one that you've first soft proof using the sRGB IEC 61966-2.1. I profile, as that is what the machine are calibrated to. The differences can be even more striking if you've spot edited your images. Even if you pay for color correction I verified that Nations will only make global adjustments to the brightness, color tone (WB), and saturation. If you've made significant spot edits you could be out of gamut in those spots even after they do their color corrections, causing them to overadjust to find a middle ground.



adamhiram said:


> Ultimately, I just want my display calibrated such that my edits will look the same on any other properly calibrated displays, while also being able to get accurate output through a professional printing service without having to edit everything a 2nd time



And I would like to win the Powerball, but I doubt that will happen either. LOL There will always be some differences. As to printing, whether you use Mpix,  Nations, or XYZ, there should be a uniformity within that lab. Once you determine the basic adjustments required it's fairly easy to apply a custom preset across the board to a batch of images.


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## adamhiram (Oct 23, 2018)

My understanding is that a printer's color space is a lot smaller than what we see on our screens, and the whole point of soft proofing is to simulate what an image will look like in that reduced color space.  I should be able to send an image that was edited on a calibrated display and saved in the sRGB color space and the printing service should be able to make it look close to what the soft proof showed.  If one particular printer tends to print images too dark, or yellows come out orange, that's not something the customer should need to adjust for.

In the examples I provided, there were some differences between the original image and the soft proof, but there were no changes in brightness, yellows weren't orange, and greens weren't brown.


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## Tim Tucker 2 (Oct 23, 2018)

adamhiram said:


> My understanding is that a printer's color space is a lot smaller than what we see on our screens, and the whole point of soft proofing is to simulate what an image will look like in that reduced color space. I should be able to send an image that was edited on a calibrated display and saved in the sRGB color space and the printing service should be able to make it look close to what the soft proof showed. If one particular printer tends to print images too dark, or yellows come out orange, that's not something the customer should need to adjust for.



Not really, but it is a different colorspace as there are different limitations on how they display colours there are different colours that are affected by those limitations..

We are looking at two different colour systems here, the additive system of your computer screen is only generating three narrow bands of colour, red, green and blue, it doesn't display any other wavelength or colour at all. This works because it stimulates the same receptors in your eye as say yellow does. Prints are a subtractive colour system so actually reflect, or try to reflect the correct colours.

This means there are some glaring differences between how you see colour on your screen and how you see it on the print. Screens generally don't display subtle differences in saturated reds very well, they have a different contrast to prints, (which affects your perception of colour). 

In short the soft proof is only a simulation on your computer screen of what the print will look like and in producing it it makes certain assumptions about the viewing conditions as regards to brightness and WB of the light you view the print in.

However...



adamhiram said:


> In the examples I provided, there were some differences between the original image and the soft proof, but there were no changes in brightness, yellows weren't orange, and greens weren't brown.



It sounds as though you're describing the colour of the paper. With subtractive systems of print the colour is translucent and really acts like a filter. The light reflects off the paper base and is filtered through the pigment so the colour of the paper affects the colour you see. Soft proofing tries to simulate this but only if you have *show paper colour* turned on. With Epson Lustre it is slightly magenta and shows in the soft proof, though when printing through PS with PS managing the colours it does try to correct for this giving as close to reference as possible. Other setting affect this such as how out of gamut colours are converted, and of course it's not possible to hide this in areas of white or bright colour, (pale yellow for instance). Here is you original file downloaded, next to the soft proof showing paper colour, and the soft proof with a rough correction for magenta, (it's a little stretched to believe that the shift in hue the slider evokes is a match to the shift produced by the paper). This might be what you're seeing as your soft proof doesn't appear to be showing the paper colour:


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## smoke665 (Oct 23, 2018)

Thank you for the explanation @Tim Tucker 2 I'd completely forgot about the color of the paper!


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## adamhiram (Oct 23, 2018)

Thanks, @Tim Tucker 2, really nice explanation!  In this case the paper used is Kodak Endura, which doesn't seem to have much of a cast to it as far as I can tell.  I definitely missed the "Simulate paper & ink" checkbox, which wound up introducing a pretty even reduction in brightness of about 8-10% depending on where I sampled (255,255,255 went to 234,237,240), but no real cast.  At least it's showing where the reduction in brightness might be coming from, and I'm glad you pointed out that extra checkbox for more accurate soft proofing.

I was doing some research and came across some interesting recommendations that may be worth sharing.  In this video, the host comments that printed images almost always come out darker and uses curves to brighten them up slightly (just midtones?) before printing.  In this one, a lab technician comments on trusting the lab to perform any necessary color corrections.  Tony Northrup makes a similar recommendation in this video.  It sounds like my best bet, if I don't want to spend a lot of time creating my own color correction export preset, is to simply check the color correction checkbox when ordering prints and let them do their thing.  It's worked out pretty well in the past, I was just hoping to take more control over the process for more consistent results.


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## Tim Tucker 2 (Oct 24, 2018)

adamhiram said:


> the host comments that printed images almost always come out darker and uses curves to brighten them up slightly (just midtones?) before printing.



LOL, it kinda misunderstands the whole system. Though colour is perceptual rather than absolute, (it's a bit of a chameleon in that is alters with it's surroundings), computers have to work in absolute colour. The RGB, LAB, HSL/HSB, or whatever colour space you use, co-ordinates describe a specific reference colour when viewed under the reference WB at light intensity *_x_*.

There is no point in calibrating a system if you're just going to *up the curves because the print is always darker*, which translates as *this file doesn't contain any absolute data as to the correct colour, I want you to print it like this so it looks the same as a 10% reduction in mid-tone luminosity and a similar perceptual reduction in saturation...* You see how the instruction quickly becomes ridiculous and meaningless, the only way you get your print to match the calibrated screen is to un-calibrate it, guess.



adamhiram said:


> the "Simulate paper & ink" checkbox, which wound up introducing a pretty even reduction in brightness of about 8-10% depending on where I sampled (255,255,255 went to 234,237,240), but no real cast. At least it's showing where the reduction in brightness might be coming from, and I'm glad you pointed out that extra checkbox for more accurate soft proofing.



This can be misleading, and confuse many. To be clear, the colour co-ordinates of 255;255;255 represents pure white when viewed under a reference WB light source at intensity *_x_*. Your soft proof is *not* showing you how the computer converts the colours as the target colour is still white, it's showing you a *visual simulation* of how the print may look different. The print will look different as it will have a lower contrast, the whites will look different because they will reflect the colour cast of the paper colour rather than an accurate reflection of the reference WB light source at intensity *_x_*. The point is to get as close to the *reference colour of 255;255;255* as possible and not print it as 234;237;240, (255;255;255 will be just the paper colour with no ink, if you add ink to achieve it then something is wrong...).

A slight magenta cast works in this way; it's not a real colour in the sense that there is no wavelength that corresponds to magenta, but a combination of red and blue, (_do not make any correlation between RGB co-ordinates and quantities of red, green and blue. Light is not RGB, they are simply co-odinates in a 3D colour space, nothing more_). Adding blue to yellow in a subtractive space will darken it and de-saturate it, the red component will shift the colour towards orange, or if a very pale yellow will shift it towards pink.

You also have to be careful with computer screens as the additive colour system is most prone to being corrected or altered by the eye, colour casts are harder to spot on computer screens than they are in print. The only way to assess colour accurately is to compare the colour on the print to a real Pantone swatch of the closest reference, what you're really trying to do with calibration is to get your screen to do the same, or as close as possible.

Now caveat first: Do not rely on my accurate assessment here as I do not have prefect colour vision, I have a moderate form of the common colour-blindness. But...

If I refer to your original JPEG from flickr and take a close and careful look I see a slight warm cast to it. It's more visible in the shadows and highlights. If I offer a slight correction on my calibrated Mac I get this, which has more neutral shadows and highlights, your original on the left:






In defence of printers; any one worth their salt knows how deceptive colour is on a computer screen and are also aware that most of us suffer the delusion that our vision is absolute and simply don't consider that it's us who don't see it correctly. So the colour corrections they offer are normally geared towards removing casts and producing neutral skin tones. They guess at what we think we see when we present the image for print and correct the things we don't see because they know it will become far more visible in print. These are their references and not the colour of the shirts because, a) they have no reference of it, and b) most people don't notice details like that.

Unless of course you tell them not to...

Once you understand that vision is not absolute, (something I've always known), then you learn to look a lot more carefully and objectively. Then you see that things combine to produce errors that are largely unavoidable. For instance if you start with a slightly warm tone, print it on paper that has a natural slight magenta tint, (_your soft proof suggests a slight cyan one but it is a representation of how the print will look once run through the calibrated process and not an accurate determination of the absolute colour which remains the absolute colour space co-ordinte contained in you file_), then view it in a domestic house with warm tone lighting reflecting off magnolia walls... You see where I'm heading with this?

If you take a peek across at another popular forum you will see quite clearly how little some photographers understand colour, they simply don't see it or the mistakes they make. So have a discussion with your printer with an open mind because your prints may have a slight warm cast, their calibration might not be spot on in the same way that your's isn't. They might always remove slight casts even with *no correction* selected because they've looked at the other popular site as well. They will always try to give you what you want but you must always accept that there will be variations. As indicated their prime concern is judging by skin tone, your's by the shirt colour, that alone will produce differences.

I can't give you a solid answer because I'm just judging on a calibrated screen, I've not seen the actual print but only, if you like, a soft proof representation of the colour difference you see. There are no absolutes in it to measure. Hopefully I've given you a fair appraisal of the difficulties that will allow you to evaluate from a more fluid model rather than making absolute assumptions of the colours you see.

_Addition_: If I look at your original I see that it doesn't have a true white point, all the colours are slightly darker. Now this is no indication that your image is under-exposed, it looks to be well exposed. But consider it in terms of absolute colour rather than the perceptual brightness of your screen. Yellow is a perceptually bright colour, it lives in the high numbers of the RGB colour space. The lower numbers you interpret as bright pale yellow on your screen actually are slightly darker with a red tint, the target RGB co-ordinates that describe that actual colour to be printed will render from slightly more orange to pink depending on the saturation, (the whiter pale yellows tending to show more red). Your print will always have less contrast and in low light will not be as bright as your screen, especially if the screen brightness is high. White points are not always desirable in prints as long as you're close, but do be aware that bright pale yellows are not readily achievable without that white point, you will see a difference. It's the trouble with actual vs perceptual and computer screens. A screen will always look bright as it generates light, a print needs to reflect light so if you add a slight density to the paper base it darkens the colour and changes your perception of it, noticeable in the bright yellows and fairly invisible in the blues.


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## adamhiram (Oct 24, 2018)

Tim Tucker 2 said:


> Hopefully I've given you a fair appraisal of the difficulties that will allow you to evaluate from a more fluid model rather than making absolute assumptions of the colours you see.


Thank you for the great explanation of these challenges, I can certainly appreciate that there are a lot of variables that can affect the perceived colors in a print.  So what do you recommend for getting more accurate colors when using a printing service?  As you can see here and here, when I used Mpix and used their color correction services, the colors and overall brightness came out pretty close to what I expected.  Am I better off just checking the "use color correction" checkbox, or is there a better alternative?


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## Tim Tucker 2 (Oct 24, 2018)

adamhiram said:


> Am I better off just checking the "use color correction" checkbox, or is there a better alternative?



Sometimes, yes. With the shots I've seen there is a very clear indication of what you require, the trouble with many shots edited on a computer screen is that those doing the editing are not aware of how the eye deceives. If I download your file again, (I don't keep it on my computer), and have a look and see:



 

From this it is very clear what you require, but look at the histogram and the colour sample taken from what appears to be a bright white. This is the actual colour that it is as defined by the RGB colour space value:



 
 As you can see it looks a little different from how you perceived it on your screen, I bet you saw it as more white with maybe a trace of pale yellow.

Next if I do a simple auto WB, this doesn't give you a *correct* WB but instead aims for a balance of primaries because that is the way your eye tries to correct it and goes someway towards what you think the colours are:



 

What the correction tells me is that there is a very warm cast on the image. So I deduce the following; you're after a straight portrait as rendered with good contrast and slightly warm colour to give a warm and pleasing skin tone. This is what you see on your screen, but it is not the reality that's described in the absolute colour of the RGB colour space co-ordinates. The difference here is probably just how your eye is correcting the brightness and colour of the image when you view it on a computer screen. In a print it becomes obvious, and more so if it combines with a slightly warm paper base or calibration that's slightly off somewhere.

I bet in time you will see this far more clearly on your screen, and about that time you will also see where the *tick colour correction* images are not quite what you want. This is because your colour vision will improve, you learn to see it more accurately with practice, (you'd be surprised just how far out it can be when you glance with an assumption that vision is absolute). Around this time you will be sending images to the printer and be getting back almost exactly what you expect.

I hope this helps.


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