ASSISTANCE WITH MONITOR CALIBRATION

[Sepiana]

Nov 20, 2021 6:05:54 GMT pontiac1940 said:

Okay, so I got that new 4K monitor a few weeks ago and pleased with it. 

But I just made a few prints (at a lab) of my wife's quilts and not pleased with the results.  
So I'd like to know what you see when you look at these images.   
Just looking for a simple answer vs info about calibration and matching image to the exact lab printer.

Which exposure looks best to you: A, B, C, D or E? 

Clive, I also have a 4K monitor. Here is what I see. 

A -- the darkest
B -- darker
C -- OK
D -- lighter
E -- the lightest

[caspa]

Nov 20, 2021 16:48:24 GMT pontiac1940 said:

Thanks all. I'll read some of caspa 's technical stuff later this evening.

The one sent for printing was C and like all prints is too dark. A,B and D,E were either over or underexposed in ACR. (BTW, the colors on my screen are nearly spot in to the actual quilt.) 

Nov 20, 2021 9:21:48 GMT caspa said:

the exposure was actually the same for each of the 5 images

That's because they are the same image with exposures altered in ACR to +/- ½ and 1 full f-stop.

Nov 20, 2021 9:01:34 GMT caspa said:

out of the box brightness set much closer to the maximum than the minimum and is the main reason why people ask "Why are my prints too dark?"

Thanks. It is the brightness that is concerning me. I made a couple of more prints at another lab and will try to go to the city and pick them up today. There might be a brightness issue with the monitor but I think the first lab screwed up and will be doing them again. 

Thanks,  

Clive

OK, so what you are really asking is which image lightness looks the best because the exposure is the same in each image and you cannot physically alter the exposure (amount of light that hits the sensor per unit area) in post processing.

The 'exposure' slider in image editing apps is more closely related to an ISO adjustment because all they actually do is multiply the rgb data, 0-255, by a factor. The 'exposure' slider obviously cannot change the amount of light that hit the sensor. The 'exposure' slider just makes an image lighter or darker without altering the actual exposure.

In any case, it sounds like either the lab screwed up or your monitor brightness is too high as I described earlier.

If your monitor is not properly calibrated and profiled then it is even more important, if you want a high chance of more than an acceptably close enough match between screen and print, to soft proof images to match what you see on screen with the original image and then make sure the lab does not alter the soft proofed jpeg you send them before they print it.

[Chris]

Clive, just to offer my 2c, If I were to print this on my system I would chose a brightness level close to D. Or, maybe somewhere between C and D. However, on "D" light is coming from one side so the top right looks a tad too bright and the lower left corner is a little darker. Both C and D seem to be in an acceptable range for me.

A = Too Dark
B = Still too dark
C = Not Bad but the lower left is shaded
D = Ideal Exposure except for the top right corner.
E = Overexposed

I do suspect the print shop has printed too dark. Good idea about asking the lab to print the the test image. The test image looks good on my monitor.

Kind regards
Chris

PS the Lagom test images are useful to check for monitor accuracy.


Lagom Test Images:
www.lagom.nl/lcd-test/


Single page version:
www.lagom.nl/lcd-test/all_tests.php

[pontiac1940]

Sepiana, yes that is the correct order of exposure and C was what was submitted for printing. Looks okay on my screen.
caspa and Chris You are correct in believing it is a lab error. This lab has been managed by the same tech for over 20 years and they do very good printing work, albeit a tad expensive. Don't laugh .. I sent two of these to Walmart to test print and the exposures were fine. So I trundled the dark prints back to the original lab and they will reprint them.
Chris, I agree that the sweet exposure is probably somehwere between C and D.

Thanks for all of your comments.

Clive

[pontiac1940]

Nov 20, 2021 20:15:59 GMT Chris said:

PS the Lagom test images are useful to check for monitor accuracy.

Thanks Chris. I've used this before and fine tuned a couple of variables. However, with my previous gaming monitor and the new 4K monitor the gamma calibration page is not as it should be. 
www.lagom.nl/lcd-test/all_tests.php

This is how it is supposed to look. However, the blending simply is not there. 

[caspa]

Nov 20, 2021 23:49:48 GMT pontiac1940 said:

caspa and Chris You are correct in believing it is a lab error.

I said it was either a lab error or your screen was set too bright.

I'm happy to see you have sorted out the issue and your experience here, similar to what I have also experienced in the past, is the reason I decided to set up my own home printing using a properly colour managed workflow from monitor calibration and profiling to custom printer profiling for various printer/ink/paper combinations.

Sure, it's a little more expensive than using a lab, especially the cheaper ones, but having full control over the process, the quality of the print, the 24/7 convenience at my finger tips and knowing it will be done correctly every time more than compensates for the slight extra cost. Plus, it's a lot of fun 

Out of curiosity and for the sake of clarity, what definition of exposure do you use when you use the word in sentences?

[pontiac1940]

Nov 21, 2021 0:23:19 GMT caspa said:

what definition of exposure do you use

Well you know I used it to mean brightness in the thread. I think most people caught on. 

[caspa]

Nov 21, 2021 2:31:35 GMT pontiac1940 said:

Nov 21, 2021 0:23:19 GMT caspa said:

what definition of exposure do you use

Well you know I used it to mean brightness in the thread. I think most people caught on. 

Yes, many people incorrectly use "exposure" and "lightness/brightness" interchangeably which can lead to confusion especially for any newbies who might read this thread at some time.

Since you seem to be aware of the technical/actual definition of "exposure" and the difference between it and image lightness, why not use the correct terms and not necessarily the more popular terms which not only minimises the potential for confusion but also educates newbies correctly?

Anyway, it's not a big deal.  The incorrect use of "exposure" and "dpi/ppi" are 2 of my pet hates and I try to correct their incorrect use when I see it in the spirit of education and I hope it is taken in that vein 

For anyone interested, I discuss with examples what exposure is and is not, and it's relationship with noise in the thread "Photographic noise explained".

[BuckSkin]

Nov 21, 2021 2:45:18 GMT caspa said:

The incorrect use of "exposure" and "dpi/ppi" are 2 of my pet hates and I try to correct their incorrect use when I see it in the spirit of education

Then I wish you would explain the differences in dpi and ppi to all the scanner manufacturers and the software programs that import and work with the scans.

If I set the scanner at any given dpi, no matter which program the resultant scan is seen in, the ppi measurements are in exact agreement with whatever dpi the scanner is set for; set the scanner for 400 dpi and get an image that is 400 ppi.

So, the way I see it for us mere mortals is that, in the digital world, dpi and ppi are exactly the same thing and there is no benefit in using the term "dpi" other than to lead to confusion.

The reverse is true when it comes to sending digital photos to become physical photos via the printer; no text I have ever read recommended me prepare images at X-many dpi; they always stress ppi instead.

The actual meaning and usage of "dpi" is within the news printers realm = dots of ink per inch.

The misuse between the two terms until now they mean the same thing is just like Hollywood's assault, abuse, and complete corruption of the term "point blank range" into some idiotic idea that "point blank range" is a very close distance; and, it is also akin to Hollywood's abuse of the term "ballistics" so much that people wrongfully think that ballistics is all about determining which weapon fired a projectile.

"Point blank range" is a long range rifleman's term that has been so much misused that I doubt a Google search would yield it's true definition.

[srmoment]

C on my screen, but mine is callibrated to 80 cd/m2.

[pontiac1940]

Thanks again to all. As noted above, it was the lab's error and they have reprinted the prints. So that was much ado about not too much.   But is it good to get opinions on monitors and calibration. 

Chris, srmoment, BuckSkin and others, based on your comments, I decided to suck it up and purchase a SpyderX Pro calibration device. I also read about DisplayCAL which is calibration software that can be used with the SpyderX Pro and other calibration devices so will likely download that as well. 

Stayed tuned. 

Clive

 

[cats4jan]

This is how I understand it

dpi is historically used for printers - dots per inch (meaning how much ink will be laid)
ppi is used to denote how many pixels are in your photo (or other projects) - pixels per inch

[BuckSkin]

Nov 21, 2021 17:31:09 GMT cats4jan said:

This is how I understand it

dpi is historically used for printers - dots per inch (meaning how much ink will be laid)
ppi is used to denote how many pixels are in your photo (or other projects) - pixels per inch

That is my understanding as well.

To see this DPI business in action, scan a small newspaper clipping with both text and a photo and then view it about twice normal size.

Some newspapers are so stingy with their ink that you can easily see the dot pattern by just looking at the paper.

[Chris]

Nov 21, 2021 17:13:24 GMT pontiac1940 said:

Thanks again to all. As noted above, it was the lab's error and they have reprinted the prints. So that was much ado about not too much.   But is it good to get opinions on monitors and calibration. 

Chris , srmoment , BuckSkin and others, based on your comments, I decided to suck it up and purchase a SpyderX Pro calibration device. I also read about DisplayCAL which is calibration software that can be used with the SpyderX Pro and other calibration devices so will likely download that as well. 

Stayed tuned. 

Clive

 

Clive, I am happy the lab has admitted its error and made new prints for you.

I have a Spyder X Pro and am very happy with it. I have found their own Datacolor software very good and the calibration is very fast compared to previous Spyder versions. Their customer service is also very helpful if you have any questions. I have calibrated my monitor to 120 cd/m2 and switched off the Spyder X ambient light measurement according to their recommendations with my particular monitor.  

Kind regards
Chris

Datacolor Downloads:
spyder-support.datacolor.com/hc/en-us/categories/4403402899730-Spyder-Software-Downloads

Support Page:
www.datacolor.com/photography-design/support-old/customer-support/

[pontiac1940]

Thanks Chris. 
I might be picking your brains.
Ordered online from Amazon and apparently the Spyder is coming from the Andromeda Galaxy as will be 10+ days coming. Oh well. 
Clive