Profiles for Web Press

[Chiefs420]

I have been charged with taking over a newsletter for our other shop. They print this on a web press. The lady there has told me that the pictures need to compensate for a 30% dot gain. Can I just apply the Dot Gain 30% profile in Photoshop and that takes care of it? When I do this it darkens the picture on my screen considerably, is that just showing you what it will look like when printed?

They also want the pics @ 85lpi and 300dpi, does this sound correct?

This is my first foray into the web design world and the newsletter has looked pretty bad in the past and I think this may have something to do with it. Any advice is greatly appreciated!

 

[TerryWyse]

Find the right ICC profile...

Find the right ICC profile...

You didn't mention what sort of originals you're dealing with (sRGB JPEGs from unknown P&S digicams?). Assuming you're starting with RGB originals, your best bet would be to try and find out their printing conditions and see if there's a "standard" ICC profile you could use for your separations. Once you find a profile that's in the ballpark, the dot gain will be properly compensated for when you convert from RGB to CMYK.

First and foremost, you should try and find out what class of paper they're printing on. If it's magzine publication stock (#3 gloss coated), SWOP Coated3 would be a good choice. A lower grade but still coated stock, maybe SWOP Coated5 would be a good choice. If it's an uncoated stock, I would start looking for either SCA or perhaps even newsprint profiles from either SNAP or IFRA (85lpi sounds more like newsprint to me). Your suggestion of using the "30% dot gain profile" is only for grayscale images. If that's the case (B&W images), I can offer some different advice.

As for the "85lpi, 300dpi" recommendation, you won't have to really worry about the line screen. That'll be taken of when they image the plates. As for 300dpi (300ppi really), it's a bit overkill for 85lpi but should work fine. Rule of thumb is 2 x linescreen so the "ideal" resolution for your photos at their *finished* or printed size would only be around 170ppi. There's no real harm having MORE resolution than required other than images will tend to look a little soft at that higher resolution with normal image sharpening techniques and, of course, take up more storage space. On the other hand, if you intend to use the images for other purposes where more resolution may be required, I'd leave them at 300ppi.

Hope this helps,
Terry Wyse

 

[rich apollo]

What kind of stock will this project be printed on? Coldset or heatset?

 

[Chiefs420]

Thanks for the help on this! Not only am I clueless to this as the shop I work in is sheetfed only, the other shop is pretty clueless about this as well. The lady that used to typeset for them got the boot. From the samples I've gotten from them she really didn't know what she was doing as far as color correction goes either. Some of her photo's are really washed out (grayscale ones) and some of them look really pluggy and dark (some grayscale and all CMYK). Thats why I'm trying to get this figured out.

As far as Coldset vs Heatset, I'm not really sure. From what I can tell from the goog thats running coated vs. uncoated? If so uncoated.

So I don't have to worry about the lpi and the dpi should be alright at 300? Also assigning the 30% dot gain profile to the grayscale photos out of PS should be fine for those (the 30% is the value I got from the other plant)?

Then on the CMYK I'm not sure what this mean: "start looking for either SCA or perhaps even newsprint profiles from either SNAP or IFRA". Are those profile I can download from somewhere?

*edit: These are sRGB JPEGs from unknown P&S digicams.

 

[manoahrsinghm]

Thanks for the help on this! Not only am I clueless to this as the shop I work in is sheetfed only, the other shop is pretty clueless about this as well. The lady that used to typeset for them got the boot. From the samples I've gotten from them she really didn't know what she was doing as far as color correction goes either. Some of her photo's are really washed out (grayscale ones) and some of them look really pluggy and dark (some grayscale and all CMYK). Thats why I'm trying to get this figured out.

As far as Coldset vs Heatset, I'm not really sure. From what I can tell from the goog thats running coated vs. uncoated? If so uncoated.

So I don't have to worry about the lpi and the dpi should be alright at 300? Also assigning the 30% dot gain profile to the grayscale photos out of PS should be fine for those (the 30% is the value I got from the other plant)?

Then on the CMYK I'm not sure what this mean: "start looking for either SCA or perhaps even newsprint profiles from either SNAP or IFRA". Are those profile I can download from somewhere?

*edit: These are sRGB JPEGs from unknown P&S digicams.

Hello,

Yes, if u r using a uncoated paper then its more likely to be a coldset.

What u can do is, for all your greyscale images use grey profile in photoshop and do ur color correction. then when you are finally making it a PDF with all other images and text which may have color information also, you can embed a ISO web uncoated icc profile for better results. these settings can be done in your adobe distiller.

By doing this you will be able to find images with more details and depth in it.

 

[rich apollo]

Gotta' know the stock, the manufacturing process, and the color mode (CMYK, black and white, Hexachrome) to do anything. Armed with this information it wouldn't be difficult to get you on the right track. The Dot Gain 30% profile you mention is a grayscale profile.

 

[Jim-CompuDoc]

It is really WAY better to do all this correction in the Rip, that way it is applied equally to every object, rather than just to the photo's you worked on.

It sounds like the system making the film or plates needs some work.