Please help with print basics!

[Timredd]

Hi guys,

noob alert,

I have created a document in photoshop that needed to be 17cm wide and 31.01 cm high - when printed. (this is for a label)

but when I go to image> image size it says 482px wide and 879 pixels high - which is not the same when converted to cm?

please tell me what is going on?

Do I need to re-create the doc?

also it is in rgb and I think only 72dpi - but I cant find where the dpi info for current doc is either - can I change these things to cmyk and 300dpi?


argg please help!

thanks

 

[Gaussian]

Go to Edit --> Image Size and there under Document Size you can set the dpi (Resolution). For high quality print you probably want 150 - 300 dpi, then set the Document Size to cm and enter the size you want.

 

[Timredd]

Go to Edit --> Image Size and there under Document Size you can set the dpi (Resolution). For high quality print you probably want 150 - 300 dpi, then set the Document Size to cm and enter the size you want.

Thanks Gaussian!

A few questions if I may,

I have changed the size

Why is the document so huge at 100% Zoom Level - ( it looks great but is far bigger than cm on my screen)

Also, I need to make 2 different sized labels - is it okay for printing to just re-size the main doc to suit? (only down)

And finally should I change to CMYK?

Thanks so much

 

[andriana]

The DPI is just the resolution, the higher it is, the bigger and better (usually; unless you have a 72 DPI and try rez-ing up to a 300 DPI, then it just appears pixelated and cruddy.)


Yes, for printing, I always flatten my layers then change to CMYK

 

[Timredd]

The DPI is just the resolution, the higher it is, the bigger and better (usually; unless you have a 72 DPI and try rez-ing up to a 300 DPI, then it just appears pixelated and cruddy.)


Yes, for printing, I always flatten my layers then change to CMYK

Thanks Andriana!

So you don't need to start with cmyk when you create the document?
Like , I mean is it better practice to start with cmyk for print rather than change it later?

Also, I still don't understand why the doc is so huge on screen yet only set to 30cm
at it's largest dimension?

Thanks

 

[andriana]

No problem!

In my opinion, I think it's better to use RGB and then change it to CMYK methinks. I only use CMYK for the correct printout quality.

On the other hand, I think it may be huge because of your DPI. It's probably at a high DPI right? Like you can even test it out for yourself, hah. Make a new document at 6 in x 6 in at 72 DPI and another 6 in x 6 in at 300 DPI. You'll see the 300 DPI is way bigger.

 

[Gaussian]

CMYK vs. RGB depends on the printer. Most commercial print shops will want the document in CMYK, but if you are printing on your home inkjet then RGB is usually better. It's impossible to answer that question without knowing where it will be printed.

The reason you are seeing the image huge at 100% is because your computer screen is 72 dpi, if you want to see the print size go to View --> Print Size.

 

[Dezigns Unlimited]

I would have to agree, make sure you do find out what colors the printer wants them in..

CMYK is usually the one though for outsourced prints..

 

[chet webley]

So you don't need to start with cmyk when you create the document?

)

Yes, if you're printing, always start in CMYK. Changing from RGB to CMYK affects some colours. Your monitor won't be displaying CMYK properly unless it's been calibrated. What this means, is that some colours (particularly blues), won't display on your screen that way that they will print. If you have access to a CMYK printer, it would be a good idea to print the colours that you're thinking if using, and see how they come out - they won't be the same as when professionally output, but it will give you some idea. If you're more comfortable mixing your colours in RGB, you can use the colour picker to change the RGB values, and it will map to the nearest CMYK value automatically.

Also, I still don't understand why the doc is so huge on screen yet only set to 30cm
at it's largest dimension?

OK, it's like this:- your monitor may have a screen resolution of 1600x1200 pixels. 30cms, in pixels at 300dpi is 3544 pixels. when you zoom to 100%, photoshop is using 1 pixel on your monitor to display 1 pixel in the image. you can only see the 1600 of those 3544 pixels, the others are "outside" the edges of your monitor.

You should also be careful of filetypes - personally, I would work in a 400dpi, CMYK, layered 8 bit TIFF file. yes, the file will be pretty big, but from that base file, you'll be able to make any other format or resolution still be of the best possible quality.

the best thing you could do before you start is talk to the printer about how they'd want the file set up, and what format they want it sent in (I'd be willing to bet that it's PDF - Which is while other minefield of settings to get right). Any decent printer will be only too pleased to give you advice - I was lucky, when I started out one of my friends was a printer and I used to hang around hos work. I also found a really cool repro studio who were willing to advise me a lot.

one more thing about the blues:- if you want it to be blue, NEVER have more the ratio of the Magenta to the Cyan lower than 8 parts in 10, or it will come out purple.

Feel free to ask any print related questions, I'd be more than willing to help (I'm a printer by trade, by the way)

 

[Steve]

Yes, if you're printing, always start in CMYK....

Hi Chet.
Are you saying CMYK for a home inkjet printer too?
Like Gauss said CMYK is for commercial printing.
Inkjet printers are RGB devices and the files should stay as RGB, are you saying that's not the case?

 

[Steve]

Here's a video by Deke McClelland explaining the differences and uses of RGB, CMYK, and LAB.

It's a 17 minute video and worth watching but if you want see the specifics regarding CMYK and non commercial printing start watching around minute 3 to around minute 4:30.
To see the hit you take in color clipping by printing an CMYK file to an inkjet printer fast forward to around 11:30 to 13:00.

http://www.photoshopgurus.com/forum...tion-color-models-rgb-cmyk-lab.html#post82064

 

[Scott20015]

Been watching the back and forth over CMYK vs RGB work files.

RGB is nice to work in, but you always need to be aware that there is going to be a color shift when you do the CMYK conversion to supply it to your printer. I work with professionally submitted pics and we get RGB, CMYK and even Lab formats submitted.

I personally work in RGB as much as possible because some techniques are only available in a RGB workspace. I wait until I am completely finished with a file then flatten and convert to CMYK. I also save a fully layered copy in RGB in case I need to make further corrections.

Just my two cents... : )

 

[chet webley]

Inkjet printers are RGB devices and the files should stay as RGB, are you saying that's not the case?

Really? I have at work:-

An Epson Sublimation inkjet which is CMYK RGB LightK
A 52" wide HP inkjet which is CMYK LightC LightM
A 1600mm wide Solvent inkjet which is CMYKOrGr
A Ricoh Laser printer which is CMYK.

I haven't seen an RGB printer since about errr... 1996? I think it was a Canon BubbleJet....

What RGB printer do you have then Steve?

One thing to remember is that commercial printers do not work in the same way as your desktop inkjet. Your desktop inkjet goes - File / Print... file gets sent to printer driver, printer driver converts file to "printer language" which then gets spooled to your printer.

My print / workflow is:- save file as .EPS, open .EPS file in RIP software, adjust settings to taste, RIP the file, spool the file to the printer.

The RIP softwares most certainly will open and RIP RGB files, but the fundamental differences between the colour spaces mean that some colours that you can see or create in RGB won't map to CMYK colour space, and vice-versa. This may not be a problem, but it could be.

I know it was a bit of a blanket statement to say "always work in CMYK", but if you ask a printer what he wants, he'll almost certainly request a CMYK image. If you're planning on doing printed work in the future, it's certainly a good idea to get used to working that way.

On the other hand, if I'm creating stuff for web, or will only be displayed on screen, I ALWAYS work in RGB. Use the correct colour space for the current job is what I'm trying to say.

One thing I have noticed, is that the vast majority of photoshop users work in RGB colour space, and use either RGB values or Hex values to mix their colours. I can't do that. I use CMYK because my work has always been output on CMYK devices, and the CMYK colour space "makes sense" to me - RGB and Hex confuse me A LOT

 

[Steve]

Hi Chet
I said inkjet printers are RGB devices and that's really not accurate, not really what I meant.
Everything I ever read, and any video I've ever seen including the one I linked to said the job of the print driver is to convert that RGB image for the printer, so converting the file in PS is unnecessary.
Commercial printers work with Cyan, Magenta, Yellow and Black, so why do inkjet printers have so many color cartridges?

I have a Canon Pixma Pro9000 with 8 ink cartridges, the Pro9500 Mark ll I believe has 10.



See the whole page Working Space Comparison: sRGB vs. Adobe RGB 1998

I can't match your expertise and knowledge of commercial printing and printing in general, but I can't see how converting an image to CMYK does anything but deteriorate the quality of an image on an inkjet printer.

 

[Scott20015]

People can say a printer is a RGB color space all they want...it doesn't make it so. ALL home printers are CMYK (plus extended gamut colors, like vivid magenta, etc). The reason for this is the ultimately simple answer...printing using inks is an ADDITIVE process, where colors on a monitor (RGB) are SUBTRACTIVE.

When you send the RGB image to your home printer it is being converted by a default profile. Best practice is to speak with the place who is doing your printing and see if they can supply you with a profile that will be calibrated to the press they are running your work on.

I personally use a GRACOL based profile for my conversions.

 

[Steve]

ALL home printers are CMYK (plus extended gamut colors, like vivid magenta, etc).

I'm not saying a printer is an RGB device when I said that originally I misspoke, it's not what I meant.
Are you saying you can get an extended gamut by converting an RGB image to CMYK and sending that to the printer?

Again I'm not talking about commercial printing, only about inkjet printers.

 

[Scott20015]

Unfortunately, I do not have enough knowledge on the subject of home printers to address this in-depth. Commercial printing is more my forte'.

But logically it seems that with a proper profile for the conversion you should be able to get a wider gamut starting with an RGB image than with a CMYK due to the fact that CMYK is rather limited when compared to RGB color space.

If you really want a challenge...check out the Lab colorspace! : )

 

[chet webley]

Hi Chet

Commercial printers work with Cyan, Magenta, Yellow and Black, so why do inkjet printers have so many color cartridges?

I have a Canon Pixma Pro9000 with 8 ink cartridges, the Pro9500 Mark ll I believe has 10.

OK, the printers with the extra cartridges; Red, Green, Blue, Orange, Green, Light Cyan, Light Magenta, Light Black etc., have those cartridges to extend the printing gamut beyond that available from a standard CMYK ink mix. For example, the Light Cyan and Light Magenta cartridges smooth out transitions between colours and print better skin tones, the Orange and Green cartridges extend the greens and reds available to print. The commercial digital presses can also have 6, 8 or 10 colours to print from, some even include whites, metallic inks and "impossible colours" like PMS021 Orange, for example.

Yes, the printer driver will be converting your RGB image to CMYK colour space (this also happens in RIP software on commercial equipment), but the thing is this:-

RGB colour mixes can create colours that can't be printed by CMYK inks (the other cartridges can help with this), but not all printing equipment has all of the extra colours (not to mention filetypes or bit depth), so to make sure that you don't create a colour in a file that cannot be printed, work in CMYK

I can't match your expertise and knowledge of commercial printing and printing in general, but I can't see how converting an image to CMYK does anything but deteriorate the quality of an image on an inkjet printer.

lolz at my "expertise"!! But the OP wasn't asking about a 10 colour, desktop inkjet. If you're using a desktop inkjet with 8 or 10 colours for printing your work (particularly from photoshop), then the drivers provided are most likely to have been set up for someone who wants to have sharp, snappy, saturated photos. In this case, RGB is certainly the way to go.


If accuracy of colour reproduction is important to the job in hand, use CMYK. If bright, punchy graphics are important to the job in hand, and your output device has "extra" cartridges over and above CMYK, then use RGB.

The best thing that you can do is to print different types of images on a selection of different papers in different colour spaces, compare them and make your own mind up.

 

[Scott20015]

You can also work in RGB with a softproof profile attached...it'll view close to what your output will look like but still leave the versatility of working in RGB.

 

[Steve]

But the OP wasn't asking about a 10 colour, desktop inkjet. If you're using a desktop inkjet with 8 or 10 colours for printing your work (particularly from photoshop), then the drivers provided are most likely to have been set up for someone who wants to have sharp, snappy, saturated photos. In this case, RGB is certainly the way to go.

Ok, you lost me.
With my printer the Pro9000 I should stay with RGB?
Most of the time I print on Canon Fine Art Photo Rag and have the correct profiles for that paper.

(And I wasn't poking fun at your "expertise", I know this is what you do)

Scott, do you mean "Proof Colors" Ctrl+Y?
I use that.
It really helps you visualize what you're going to lose and adjust for it.