Prepress Proof Approval Via Email - Consumer End (Noob)

[Make_More_Art]

Hello all,

I'm working with a printer/textile manufacturer in China to reproduce my highly color sensitive photographic images on silk satin.

I will soon receive a prepress proof, I assume a pdf, via email for my approval.

What is the standard method for checking electronic proofs and asking (via email) for specific color changes?
I was considering placing my original RGB filel along with the CMYK prepress proof in photoshop and alternating between the two, to identify unacceptable color variances.
If I find a problem, I could use the eyedropper tool and sample the original RGB value, and provide the printer with it's associated CMYK hex value. Do you think this is a wise thing to do? - or should I just say something less specific like, "it's about 10% too much cyan"?
From what I understand, printers optimize their CMYK values to their printers and printing surfaces, I'm worried that if I give them a specific hex value, it may throw off the color balance for the whole image.
Thanks!~MMA

 

[Schnitzel]

Sorry, in my opinion, this is not going to work for you, and will cause you a lot of headache.

You cannot make color corrections based on the appearance of an electronic proof on your monitor. You must see a physical print in order to do that, for several reasons:
- Is your monitor calibrated and profiled? If not, the colors you see on your screen are "incorrect", and do not correlate to the printed output.
- Is your print provider using a color-managed workflow? If not, the proofs you get from them do not correlate to their printed output.
- Even if everything is color-managed, a monitor is not a sheet of paper or fabric. Their appearances will never match 100%, and color-management software can only do so much to overcome these differences when displaying an electronic proof.

If your demands are for very high color accuracy, you must get a hard copy for inspection.

I didn't quite understand your eyedropper sampling question - do you intend to tell the printed to change only a specific area in the photograph? I believe it is your responsibility to do that in the original RGB file. When you write "provide the printer with its associated CMYK hex value", what kind of CMYK are you talking about? Did the print provider supply you with their in-house ICC profile? If not, the CMYK value you supply them is meaningless to their workflow.
Also, giving the printer very specific instructions such as "it's about 10% too much cyan" is a recipe for trouble, because it is not necessarily the correct solution to the problem. It is the printer's job to know how to overcome the problem.

You are correct with your last assumption, that the printer is most likely converting all input CMYK values to their own requirements. If you do not have (and use) their ICC profile, the CMYK values you give them will most likely do harm than good.

 

[Make_More_Art]

Thank you, you've provided me with some valuable information. I asked this question in a digital photography forum and was advised to alter the proofs in photoshop. Obviously, I won't be taking that advice. The original files I sent my printer were Adobe RGB TIF's. At this point, if the proofs match up reasonably well with my original files, I'll be satisfied.

I'm left with the following question; If the proofs I receive are significantly different from my original images - how should I go about asking for alterations?

Thanks again ~MMA

 

[dabob]

Thank you, you've provided me with some valuable information. I asked this question in a digital photography forum and was advised to alter the proofs in photoshop. Obviously, I won't be taking that advice. The original files I sent my printer were Adobe RGB TIF's. At this point, if the proofs match up reasonably well with my original files, I'll be satisfied.

I'm left with the following question; If the proofs I receive are significantly different from my original images - how should I go about asking for alterations?

Thanks again ~MMA

In Person . . . it's a long flight but might be worth it in the end . . .

 

[Make_More_Art]

Thanks, dabob

In person does seem to be the most reasonable way to do this. My printer/manufacturer is in China. However, they do offer a method of communication that appears to be similar to Skype - not ideal, but it's what we've got to work with.

For the sake of my own sanity - Let me see if I'm coming closer to understanding this process.

1. I send my designs to my printer
2. My RGB files are translated into the CMYK settings appropriate to my suppliers printers.
3. My supplier prints my designs and sends me a photo of the results (ideally a hard copy).
4. I bring my concerns to my printer, in this case via Skype.
6. Repeat steps 3 &4 until I'm reasonably satisfied with the outcome.

This has been an interesting ride. I'll continue to do my research, and we'll get there.

Thanks guys, this has been very helpful.

~MMA

 

[AP90]

Thanks, dabob

In person does seem to be the most reasonable way to do this. My printer/manufacturer is in China. However, they do offer a method of communication that appears to be similar to Skype - not ideal, but it's what we've got to work with.

For the sake of my own sanity - Let me see if I'm coming closer to understanding this process.

1. I send my designs to my printer
2. My RGB files are translated into the CMYK settings appropriate to my suppliers printers.
3. My supplier prints my designs and sends me a photo of the results (ideally a hard copy).
4. I bring my concerns to my printer, in this case via Skype.
6. Repeat steps 3 &4 until I'm reasonably satisfied with the outcome.

This has been an interesting ride. I'll continue to do my research, and we'll get there.

Thanks guys, this has been very helpful.

~MMA

I guess my main question/concern here is why are you outsourcing to China to make things more difficult? I understand that they're printing is cheaper, but surely there is a company fairly close to you that you could work with that would give your comparable rate and would save money by seeing hard copies of the work to match color exactly. The only way I could see China being more viable is if the products are staying in China. Just seems like a huge hassle to have them printed up over there if they're being brought back here to the states.

 

[mattbeals]

Can this kind of color critical work be done remotely? Yes. Either by shipping hard proofs back and forth with measurement data or by using a color managed workflow. Using their online/skype-like system is NOT the way to do it. You'd be better off going there. It will be faster, more efficient and more likely to end up with a more desirable result.

 

[kansasquaker]

Let me put this in some perspective for you:

1. You say your work is 'highly color sensitive photographic images'. Therefore, the results you want already require a printer with a reasonably high degree of skill in color management.
2. You say you are printing on silk. That is an extremely difficult process to color manage under the very best of circumstances.
[FONT=arial, helvetica, sans-serif]3. This isn't a nice thing to say but it's true and somebody should tell you . . . You have shown no understanding of the process of converting RBG to CMYK and even less understanding of how printers color manage the printing process. This is not something you can learn from online forums in a couple days. Read through some of the color management discussions here. There are guys who are ten times as smart as me, with decades of experience who don't agree on how to handle some of the issues you'll face. You are wandering through a mine field.[/FONT]

[FONT=arial, helvetica, sans-serif]​So far, you're attempting to do something very difficult and you have essentially zero understanding of the process.[/FONT]

[FONT=arial, helvetica, sans-serif]4. You're next step is to send the job to a printer half way across the world to save money. This is the exact opposite of what you should be doing. You need help from a qualified professional who you can work with. I don't know what your job entails, but I think you really need to see some sort of hard proof made by the actual printing process for each image. Perhaps you can fly to China and get the help you need and end up with desirable results. That is a plan that has some chance of success. But trying to soft proof this is almost a guarantee that it will go badly. [/FONT]

 

[Simon Ivarsson]

Hi,
I've been working in the industry for a while with some large companies.
Normally this is how an approval process works.
Content and technical stuff can be approved with pdf's or web approval systems.
But when it comes to colour, it's always done with a colour managed hard copy that has been verified to be within the customers Delta E requirements.
After everything has been approved there is always someone at the printer to check the actual print. And yes, they fly all around the world for this press-check.
Once I flew to Korea, checked the print and flew back home again...

 

[Possumgal]

Forgive me if I missed it, but you also have the problem of RGB having a wider gamut than CMYK. Also, colors on a monitor will appear brighter than those printed on fabric, unless they're using plastisol ink. With the printing you described, I doubt they're using plastisol, probably more like a dye, in which case you may think your fabric print looks faded. It's just the nature of printing on fabric, so be prepared.

 

[kansasquaker]

Forgive me if I missed it, but you also have the problem of RGB having a wider gamut than CMYK. Also, colors on a monitor will appear brighter than those printed on fabric, unless they're using plastisol ink. With the printing you described, I doubt they're using plastisol, probably more like a dye, in which case you may think your fabric print looks faded. It's just the nature of printing on fabric, so be prepared.

But none of that will be a problem as long as he puts the eyedropper tool in photoshop over the area right? </sarc>

 

[gcplau]

...it's how I see your problem:
1. fundamentally you are not aware of the difference between RGB & CMYK can be huge especially your image has out of gamut colors;
you need so many things in place in order to more accurately visualize the outcome when you create the original image in RGB, including:
- IPS LCD monitor well calibrated and has broader viewing angle (i.e. color won't shift that much when you look at different angle)..such as EIZO; and you have to keep your display calibrated and check periodically;
- you need to set correctly your working RGB whether choice is Adobe or sRGB; and also need to tag correct RGB to your image;
- you need CMYK icc profile provided by your printer, so that you can have a closer (not exact) preview of the outcome (photoshop allow you to preview using destination icc instead of converting your data)
- finally when you convert from RGB>CMYK (which you obviously not have a clue how deep you need to know) you need to know your image is best using what rendering intent;
- your final printer's printing mechanism whether it's silkscreen, inkjet or others insert add'l color shift factors which is more your printer's responsibility than yours...but if your approval process is a soft proof....definitely you end up in lots of problem.

#1 If you already have your image in place in RGB.... try to learn quickly how you can visualize the outcome using above suggested, so that firstly, you set a realistic expectation of how much percentage CMYK can simulate your RGB visual;
#2 ask your printer to see if they can provide a known delta-E tolerance digital proof with proper white point simulation (cos' your fabric is not the usual white as your screen or known paper white....simulate the fabric white); ask your printer to show you pass sample of digital proof vs. actual fabric print (this give you another good idea how a proof-simulation differs from real product)
#3 there seemed to be some inkjet printer that can print on fabric, see if your printer can use those technology/tools and offer you an actual "proof on fabric". Nothing is as good as proof on your real substrate.

Hope my 2 cents help.

Finally, the eyedropper idea will not work, unless your environment is very much tuned to the professional standard and you really know what you are doing.

 

[maas]

My 2 cents, print is all about putting an ink film on a substrate, the measure of which is density, colour is a prepress constraint and measured in % so unless you give the printer what he needs to meet your expectation you will be running around in cicles

 

[Andy_warp]

You say textile manufacturer...what type of printing are they using? I run dye sublimation and the issue we have with ANY type of soft proofing is our ink gamut. In comparison to the gamut of photographic images it is small. It's small relatively to other types of CMYK printing. The problem is you'll never reproduce taking away light (a monitor) by adding ink to white (cmyk printing)
People ask from time to time if I can make my cyan "brighter"

How? Adding more ink? Nope. Another factor will be the white point of your substrate. Images may look dull just due to the brightness of the white.

We use our digital proofs for layout elements ONLY such as crop/text/graphic elements. Hard copy proofing is the only way to go if color is critical.

 

[Michael C. Lane]

this is interesting
If you are designing anything in color, you should be familiar with the two most common color models: RGB and CMYK. For most day-to-day design intents and purposes, what you really need to know is that RGB color is used for digital communications, like television or websites and CMYK is used for stuff made for print, like brochures.

RGB stands for the colors red, green, and blue, the colors widely recognized in design fields as the primary colors. The RGB model is known as an additive model, where colors are added together to make up what we see on the screen. Basically, pixels on a television set or computer monitor create tiny pixels that, if viewed under a magnifying glass, are one of those three colors. Light is projected through them, blending the colors on the eye’s retina to create the desired colors.

CMYK, on the other hand, stands for the colors cyan, magenta, yellow, and black. CMYK is a subtractive model. This gets a bit complicated, but the idea with subtractive models like CMYK is that colors from the spectrum are subtracted from natural white light into pigments or dyes. These pigments, then, are printed onto paper in tiny little cyan, magenta, yellow, and black dots. If you were to take a magnifying glass to a magazine cover, for example, you would see that the main image is really just a bunch of dots spread out, some closer than others, to appear like the colors we want.

Neither system of color is perfect (neither can actually reproduce all the available colors in nature), but both are good enough to look very realistic to the human eye. You don’t really need to know all the technical stuff to be a good visual communicator, but you should at least be aware that CMYK and RGB are used for different media. If you create a brochure, for example, using RGB color, when you send it to the printer (who uses large bins of ink that are made in cyan, magenta, yellow, and black), your colors won’t be quick right when printed.

If you are working in Photoshop, make sure you set the appropriate color mode (it is one of the options when you first open a new document) for the media you expect to present your work in. If it’s a website, RGB; if it’s going to be printed, CMYK.

regards
https://www.stickercanada.com/