Processing Photos

Islaoo

Member
I work in the Prepress Department for a newspaper. We have recently changed printers and the new printer is printing everything a lot heavier than out previous one. This is resulting in our photos (mono ones) being much to dark. We use Photoshop to process them. I have adjusted the ink levels that we work to and this has helped a lot but they still don't look great, any suggestions? For our CMYK photos, we use an ISO Newspaper profile but is there a profile we can use for mono photos which would help? Thanks.
 
Re: Processing Photos

There is also an ISO Newspaper Grayscale profile out-there that you can use. You can also modify one of Photoshop supplied profile (such as "30% dot gain") by playing with it's gradation curve to compensate for that extra dot gain.
 
Re: Processing Photos

Does your printer have a custom icc profile? If not, I would suggest using the [SNAP|http://www.color.org/registry/index.xalter] profile.
I handle a lot of photo processing at a newspaper and had a similar problem. Someone here suggested SNAP and I could not be happier. Whatever cmyk profile you use, just load that same profile into grayscale.
When you are toning your images, you can go to view/proof setup/custom, then choose cmyk or grayscale (whatever you are working on) and check the box for simulate black ink. This will give you a better idea of what the image will look like because of the very weak black ink in newsprint. I don't tone with simulate black ink checked, but I do look at it after I am done just to make sure it looks ok.
Also, customizing an icc profile in photoshop is a bad idea. There is a post a while back under color management where the kind folks here informed me of this folly. For one, you won't have the ability to proof your images using simulate black or simulate paper color because you can't make a device profile in photoshop. The SNAP profile is a device profile for newsprint, so it contains the information needed to simulate the lightweight paper stock and the weak black ink.
Ultimately, you will want to tone by the numbers. In grayscale, keep the midtones of light skinned faces in between 30% and 40%, don't let any part of the picture (except for specular highlights) go below 4% because nothing will print on that part of the page and anything above 85% will fill in, so only let the areas of the photo that are dark and devoid of detail go above 85%.
Finally, ask your printer if they want the profiles embedded. If they unsure of what you are asking, don't embed them. The printer might want the profiles embedded so that they can see your pages the way you intended them to look, but if their RIP is set to convert profiles to a different profile, your perfect numbers might change. The bottom line is that the safest thing is to not embed.
One final thought, make sure your distiller job options are not changing your colors as well. I hope some of this helps. Good luck.

Dan R.
 
Re: Processing Photos

You can do some interesting things with Elpical Claro, which is well suited for newspapers, for automatic image enhancement. If you would like to go through it we can. I can even process some sample PDF's or images if you like.
 
Re: Processing Photos

I couldn't agree more with the fact that modifying profiles in Photoshop is not the best way to proceed, I actually use both ISO newsprint and SNAP profiles for newsprint advertising. My point is just that for grayscale images, you can do a pretty good job by modifying one of Photoshop's "dot gain" grayscale profiles (by tweeking the curve where you need to and save the result as a profile) to compensate for higher or lower dot gain. Will do the work when you go "convert to profile". May not be well suited for display soft-proofing though. As for embedding the profile, you should always do so since embedding does not, by itself, change the (perfect) cmyk values of your image and ensure that everybody sees the same color on their (hopefully profiled) monitors. As for in-rip icc profile conversions, the sole fact of not embedding profiles to your images will just mean that the rip will have to tag it with another source profile if it's configured to do profile conversions which could make the end result look even less predictive. Anyways, in case your printer actually does in-rip profile conversions, you should get that profile from the printer, use it to do your own conversions, embed that profile to your images and then since source and destination profiles will be the same, no conversion will occur (given that the rendering intent is the same).

Edited by: Colorblind on Jan 5, 2008 4:10 PM

Edited by: Colorblind on Jan 5, 2008 4:13 PM
 
Re: Processing Photos

> the rip will have to tag it with another source profile if it's configured to do profile conversions which could make the end result look even less predictive.

Is that common? Why would the RIP be set up to assume the source profile is something completely different than the output profile? If their was no profile present, wouldn't the profile that the RIP assigns be the output profile?
If I am wrong about that, please let me know.

If they convert, finding out what profile they convert to is definitely your best bet.

But anyway, you said your other printer printed your grayscale photos better. Maybe they were compensating for the dot gain for you. If you were happy with your results from the other printer, you could ask the new one to compensate for the dot gain in your grayscale images too. Just a thought.

Dan R.
 
Re: Processing Photos

Thanks, I will have a look at SNAP, some good advice. Let you know how I get on. The Company I work for are pushing to start using Fotostation Pro to process the photos, any experience with this? I am not sure if it will process them better/worse/same as Photoshop or what advantage it gives us to change the program we use. I think if it aint broke, don't fix it, we have always used Photoshop in the past and it has worked for us, obviously with the change of printers it will take time to get everything back up to the standard we are looking for, but I find Photoshop to be good for the job. I have spoken with another newspaper who use it and they recommend it, but I don't know anyone else who is using it.
 
Re: Processing Photos

Yeah, I would like to know how it works for you. It has helps us a lot. I don't have any experience with Fotostation, but maybe someone else here does and can offer you some advice. I really like the integration of all the Adobe apps, so there would have to be a very good reason for us to change to another application for photo processing.
 
Re: Processing Photos

Islaoo,

Whatever app you use to "process" your images is only going to do what you tell it. I've never worked with Fotostation, but I wouldn't expect it to just fix your issues.

The most likely scenario I can think of is that the previous printer was using curves in the plating stage to lighten up their imagery, and the current printer is not. Very simple to rectify.

And STAY OUT of the Custom CMYK (or Custom Dot Gain) settings in Photoshop. Photoshop is not a profile editor. When you go into the custom color engine you are no longer working with any existing profiles. You are creating a very simple, but new, profile. Personally, I hope Adobe will do away this option soon.

rich
 
Re: Processing Photos

> Personally, I hope Adobe will do away this option soon.

Well, I use it for at least one thing. When I have a color ad that contains 4-color black element that should be solid, I go to convert to profile-custom cmyk and change the black generation to maximum. This fixes the problem almost every time and is easier than trying to select out rasterized text. So, I hope they don't trash it, but they should definitely make it more clear that is should not be used to make custom profiles for professional print. I have not seen this explained in any of Adobe's literature on Photoshop.

Dan R.
 
Re: Processing Photos

To get the photos light enough, I can't just keep pulling back the curves can I, will the photo not just turn to mush? I have already taken the max level down quite a bit and they are still too dark. I thought I may try the ISO Newspaper profile for greyscale to see how this helps but any other suggestions would be appreciated. Colour management is not my best area and changing printers has been a nightmare as I am unsure what the best way to rectify the problem is. I am also not too certain about how to set the profiles up in the Photoshop colour settings as someone else did this originally. Help!
 
Re: Processing Photos

You can just pull up your curves. You can open curves, click right in the center. In the curves dialog box, there is a box for input and output (they won't appear until you click on the curve). When you click in the middle, your input should say 50. In the output box add what you think the dot gain should be. If it really dark, add 30%. In other words, type in 65 in the output box. Yes, the picture will look like you just sucked all the contrast out, but it will not print like that. The last thing you want to do is sharpen the picture with unsharp mask. Sharpen it right to the point where you think it looks like too much. It will look posterized, but will not when it prints (remember, dot gain.)

What Rich was saying is that your other printer probably recognized that your pics would print to dark and they adjusted for the dot gain when they were making the plates. The printer should be able to do this better than you because they should know exactly how much dot gain to compensate for at different points on the curve. I do my own compensation because I am a control freak and I want to know what the pic is going to look like.

As far as color settings in photoshop,

You can download SNAP or ISO newspaper, try both and see which one works best for you.
In Photoshop go to Edit-Color Settings-and under working spaces choose grayscale and go up to load grayscale, then find the profile you downloaded and load it. Under color management policies, make sure preserve embedded profiles is selected for every working space and I would uncheck all the profile warnings unless you want to see a warning almost every time you open a picture. Save these settings with any name you want. After that, you can go to the folder where the color settings are saved and make a copy of the file to load on every computer you have.

I have attached the color settings that we use. If you want to try these go to edit-color settings-then choose load (near the top right of the dialog box), then select the file I attached. These settings use SNAP for grayscale and SNAP for cmyk.

Even though this will help compensate for dot gain, it is not your printers device profile, so don't rely completely on your screen. You have to pay attention to the numbers in your info palette. Move around a picture with the eye dropper tool. If any part of the picture is above 85%, it will look like solid black when printed.

Finally, when you get your numbers right and the picture looks pretty good, go to view-proof setup-custom-under device to simulate, make sure working gray (or working cmyk, if that is what you are working on) is selected. check the boxes for simulate paper color and simulate black ink. Now your picture will look really bad, but it will be closer to the way it will actually print. What this is doing is simulating the device and paper you are printing on (a web press with newspaper stock.) If you make a custom profile in photoshop, these options will not be available to you because the profile you created has no idea what you are going to print on. SNAP is made to simulate a printed newspaper on your screen as well as give you better conversions from RGB. SNAP is my recommendation, but the best thing you can do is call the printer and ask someone in prepress what icc profile you should use. If they say, "huh?", then use SNAP and don't embed your profiles.

Dan R.


It would not let me attach my color settings. If you would like to try them, send me a message.

Edited by: bluskool on Jan 8, 2008 1:07 PM
 
Re: Processing Photos

> {quote:title=bluskool wrote:}{quote}
> > Personally, I hope Adobe will do away this option soon.
>
> Well, I use it for at least one thing. When I have a color ad that contains 4-color black element that should be solid, I go to convert to profile-custom cmyk and change the black generation to maximum. This fixes the problem almost every time and is easier than trying to select out rasterized text. So, I hope they don't trash it, but they should definitely make it more clear that is should not be used to make custom profiles for professional print. I have not seen this explained in any of Adobe's literature on Photoshop.
>
> Dan R.

You've hit on a key issue, bluskool. I have profiles made with differing GCRs to accomplish exactly what you're talking about. For everyday use I have profiles with "typical", kind of "middle-of-the-road" GCR. For images with high neutral content, I have profiles with over-the-top, super-duper, maximum GCR.

> {quote:title= Islaoo wrote:}{quote}
>To get the photos light enough, I can't just keep pulling back the curves can I, will the photo not just turn to mush? I have already taken the max level down quite a bit and they are still too dark. I thought I may try the ISO Newspaper profile for greyscale to see how this helps but any other suggestions would be appreciated. Colour management is not my best area and changing printers has been a nightmare as I am unsure what the best way to rectify the problem is. I am also not too certain about how to set the profiles up >in the Photoshop colour settings as someone else did this originally. Help!

What bluskool said is correct. Your printer can accomodate some of this during plating. If you can find out what kind of dot-gain figures your previous printer was achieving and what kind of dot-gains your current printer is hitting then it's just a matter of subtraction. If you can't get those values, then you can work by trial and error with your current printer. Just as a ballpark figure to begin with have them pull 10% out at the 3/4-tone. This will open the shadow end a bit, which allows the printer to run heavier solids without plugging up the images. This will give better contrast.

If you need help with Photoshop settings feel free to contact me off-list.

rich
 

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