Digital Cameras are not good for printing in CMYK!

Canon EF 17-40mm f/4.0L USM

11/25/2004 04:24:55 PM · #1

That is what a printer told my graphics people!!! ... Please read on:

I'm hoping that somebody here knows enough about printing to shed some light on this mistery.

I took a picture for work, to be used as our company Xmas card. The image was kept dark on purpose, in order to properly represent a homey Xmas scene. Here is the image:

Click for larger image

When I printed it on my crappy HP colour printer, the image came out great. The detail that I could not see on the computer screen came to life. Shadows had alot of details. The bottles and glass are also very crisp and full of life.

So we sent the high res TIFF file off to the printer to get our Xmas cards printed. The proof comes in the next day and the image is very dark, and lacking in shadow detail. The image looks a little washed out and the resolution does not seem very deep. I immediately call our graphics people who tell me that they will call the printer and tell them to get it done properly. This is what they were told:

- the image was dark and could not print any better
- the image was taken with a digital camera, which is not ideal for this type of printing (off-set printing), because it was taken in RGB and that they print in CMYK. They claim the colour is lost in the transfer. They also claim that the image could be reworked to print better but that it would take much work to get it up it's potential (lots o' money!).
- they also said that their printers could NEVER match the image resolution of an EPSON style printer, which are designed for digital image printing and print at a much higher DPI than their off-set printers.

I don't know much about colour space and RGB vs CMYK, etc, but this sounds like alot of BS to me. After all, the image was taken with my 20D and all of it's 8MP!

Can anybody shed some light on this.

Thanks.

Message edited by author 2004-11-25 16:27:39.

digistoune

Canon EOS-20D

11/25/2004 04:42:13 PM · #2

Forgive my ignorance on this issue but aren't magazines and such printed in the CMYK color space? And aren't alot of photographers publishing photographs in those magazines capturing their images digitally?

jimmythefish

Canon EOS-10D

11/25/2004 04:42:24 PM · #3

I'm not formally trained as a graphics designer, but I used to go through this all the time with printers. Offset printing is a different game, so you need to approach it a bit of a different way.

Start with a properly calibrated monitor.

You want to avoid a situation where colour profiles are assigned to your image, rather than converted. If you fire an RGB image into a CMYK print process, the colour will be shifted noticeably. You need to convert your image to CMYK in Photoshop, preferably with the CMYK .icc file which the print shop uses.

Use Image > Mode > Convert to profile... and then select the .icc file the print shop gave you.

That way, you'll get more consistent results.

Message edited by author 2004-11-25 16:57:19.

11/25/2004 04:49:01 PM · #4

For the printer to print the picture on an offset press, they need 4 plates (C)Cyan (M)Magenta (Y) Yellow (K) Black, the image will look different to an RGB picture.

Most decent software programs will convert from RGB to CMYK, so if the printers have PS all they need do is go IMAGE>MODE>CMYK COLOR.

If you have PS you can do it yourself, if you look a in the layers palette under channels, you will have 5 layers CMYK Cyan Magenta Yellow Black.

This how we do all our stuff. Not sure why your printers can`t.

George

AmiYuy

Nikon Coolpix 8700

11/25/2004 04:58:01 PM · #5

Originally posted by Harold1066:

This how we do all our stuff. Not sure why your printers can`t.

I'm sure printers can, and I'm sure they do, the thing is that they don't know what you want your image to look like and WILL NOT touch it up for you if they convert it. I've worked with publishing companies enough to know that even if you send them an obvious error, they WILL NOT correct it for fear of getting in trouble. They print it as you send it, so you better have it right when it's sent.

Canon EF-S 10-22mm f/3.5-4.5 USM

11/25/2004 05:13:19 PM · #6

Originally posted by mariomel:

They also claim that the image could be reworked to print better but that it would take much work to get it up it's potential (lots o' money!).

Originally posted by AmiYuy:

But to say that it "would take much work to get it up it's potential (lots o' money!)." is BS; as jimmythefish pointed out, the printers will have their own .icc file so they will have a good idea what the CMYK will look like plus if a printer is unsure they usually send the client a proof or ask them to come in and proof the job before printing.

G

digitalpins

Canon EOS-60D

11/25/2004 05:55:32 PM · #7

I am a graphic designer/creative art director and thats not true, I use film photographs and digital photographs all the time and both of them come out great. But that depends on what the quality of the photos you recieve from people.

11/25/2004 05:56:53 PM · #8

I did this in PS7 afterwards and saw NO DIFFERENCE in my image. Should it have changed?

Originally posted by Harold1066:

Most decent software programs will convert from RGB to CMYK, so if the printers have PS all they need do is go IMAGE>MODE>CMYK COLOR.

If you have PS you can do it yourself, if you look a in the layers palette under channels, you will have 5 layers CMYK Cyan Magenta Yellow Black.

Canon EF 55-200mm f/4.5-5.6 II USM

11/25/2004 06:22:39 PM · #9

Originally posted by mariomel:

I did this in PS7 afterwards and saw NO DIFFERENCE in my image. Should it have changed?

Sometimes there is a slight colour change but not always. If in the channel palette you have the 5 channels then it`s CMYK.

G

orussell

Canon EOS Rebel T6s

11/25/2004 06:34:53 PM · #10

Originally posted by Harold1066:

Originally posted by mariomel:
I did this in PS7 afterwards and saw NO DIFFERENCE in my image. Should it have changed?

Sometimes there is a slight colour change but not always. If in the channel palette you have the 5 channels then it`s CMYK.

G

Is CMYK in PS the same colour space as SWOP CMYK which most printing presses use?

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

11/25/2004 06:58:59 PM · #11

Originally posted by orussell:

Originally posted by Harold1066:

Originally posted by mariomel:
I did this in PS7 afterwards and saw NO DIFFERENCE in my image. Should it have changed?

Sometimes there is a slight colour change but not always. If in the channel palette you have the 5 channels then it`s CMYK.

G

Is CMYK in PS the same colour space as SWOP CMYK which most printing presses use?

As far as I know SWOP is the US CMYK which is different to Europe, so I can`t say :(

GeneralE

Canon PowerShot S3 IS

11/25/2004 09:39:50 PM · #12

Yes it is true that the CMYK color gamut is severely restricted compared to RGB. With offset presses, you can reproduce about 7000 distinguishable colors. In "normal" 24-bit RGB mode your monitor is supposed to be able to reproduce 16.7 million colors. Many colors cannot be reproduced at all in CMYK, e.g. vibrant blues/purples or hot pinks are especially hard.

While it is "easy" to convert RGB > CMYK with Photoshop, there are many settings which can be adjusted to control the final output, including maximum total ink coverage allowed and method/degree of Black generation.

Another limitation is that presses print small "halftone" dots of each color to simulate different colors. The press it a binary device, there's either ink or no ink. Inkjet printers typically use the the same set of ink colors, but are able to spray them on in much smaller dots/droplets than a true offset press can handle, which makes it look like the resolution is better.

Unless you have a good hardware-calibrated monitor and know your way around color management settings, you won't be able to tell much from the screen. Remember, even if you convert the data to CMYK, the monitor is still displaying it in RGB, and via transmitted rather than reflected light -- the other reason printed pieces often look better on screen.

The part about can't do it "because it's digital" is BS -- the digital data from a camera is exactly the same kind of RGB data you'd get from scannning film or slide or print. The difference these days is that those scans were usually handled by an experienced scanner operator, who can adjust highlight/shadow exposure, color-cast, selective color-correction, dot-gain, and other similar necessities in the scan operation, so the person who is laying out the pages can just drop the finished photo into the layout. Now print shops are being forced to take on those functions of adjusting the raw photo into a printable result, and many don't have the time/expertise to do so. For comparison, the place I work will pay about $25-40 to have a 4x5 or so photo scanned and prepped for CMYK printing.

Images like this example with lots of detail in the dark tones are very hard (but not impossible) to print well via offset printing. Besides the file prep, other factors are the press/ink type, paper, and press operator experience. Offset (especially 4-color) is also uneconomical in runs of less than 500-1000 pieces; for example, for 50 cards you'd probably be better of printing on a "digital press" (e.g. Indigo) or just making photographic prints and gluing them to the cards.

Message edited by author 2004-11-25 21:43:13.

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

11/25/2004 10:53:06 PM · #13

Thanks Paul, and all the others. I guess part of what they said is true. Is there something I as a photographer can do to make this process easier for the printers?

Originally posted by GeneralE:

GeneralE

Canon PowerShot S3 IS

11/25/2004 11:07:56 PM · #14

Originally posted by mariomel:

Is there something I as a photographer can do to make this process easier for the printers?

If you have Photoshop (not Elements), you could make the conversion yourself and bring them a CMYK file. To do that you would need certain information from the printers:

-Maximum Total Ink coverage (usually between 280-310%)
-Halftone screen ruling (probably 150, 175, or 200 LPI)
-Press Dot Gain (probably 15-25%)
-Minimum/maximum (highlight/shadow) values (probably 5-10% and 90-95% respectively)
-Black Generation settings (even they may not know -- "Medium" is probably OK)

In general, an image usually has to look kind of washed-out and flat on the screen to print OK. An image which is rich and contrasty on-screen will usually end up too dark on an offset press.

Set the Photoshop "Info" window to show CMYK colors in one of the fields -- I usually have my Info window set to show Grayscale and CMYK values.

You might see if you can find books/articles on scanning and CMYK conversion ... anything published in the last 15-20 years is probably current enough for that part of the process -- just substitute photo capture for scan.

One more thing ... be willing to pay for a color proof before printing!

Message edited by author 2004-11-25 23:09:22.

GeneralE

Canon PowerShot S3 IS

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

11/25/2004 11:24:24 PM · #15

If I was given this file at work, this is approximately what I would have done. Note that the final image is again in RGB, but it was first converted to CMYK and then back to RGB, so any gamut compression should be reflected in what you see.

graphicfunk

Canon EOS-20D

Canon EF 28-135mm f/3.5-5.6 IS USM

11/25/2004 11:41:40 PM · #16

The general is 100 correct in his explanation. There are many settings and controls which must be made to allow a fair conversion to 4 color offset. For example you must trim at the two extremities of darkness and brightness. Four color offet, as the general explains, is printing dots and the black plate is used to reinforce certain values. However, the image never equals what you see on your monitor. But be assured that digital has been employed for quite some time for catalogues. For example, non digital images make halftone negatives from the original with a 4 color process camera to recreate the four color separation and then the smart printer begin the color control process. Many problems arise and one is the moire patterns which the printer solves by angling the different halftones to reduce this phenomena. A lot is also dependent on the line screen chosen as well as the stock that it is being printed on. 133 is standard for calendered stock while quality prints use a higher number. Many printers have already moved into this realm with sophisticated computer equipment and can turn around your tiff within a very short time at no great inconvenience or cost. You must understand that sometimes a short run suffers and probably ran on 11x17 single color pass machine where the end result is not known. However, I know very few printers that attempt 4 color in single pass machines.

Well, look, it is an industry that requires a different mindset because the image has to be converted and the end result will never have the punch that you get in your screen or printer. It takes a little time to tweak all your criteria and of course, low contrast images are the pits because once the black plates spreads its ink, the image will look even duller. Your screen is using the additive color space, the printers world is like that of the artists pigment or subtrative. Best to spend some time with these subjects to avoid common pitfalls.

this post was corrected to elaborate the process I incorrectly labeled as scanning. I used the term very loosely simply because a similar process takes place with a scanner. However, a process camera simply intervenes a mask with the prescribed dots in front of the film for the exposure. This is done for each color. The negatives are then burned unto an aluminum plate.

Message edited by author 2004-11-26 00:25:32.

graphicfunk

Canon EOS-20D

Canon EF 28-135mm f/3.5-5.6 IS USM

11/26/2004 12:26:00 AM · #17

Force to add an edit. Sorry. dan