Colour Printing

[grasshopper]

Can anyone help?

I normally produce my renders for on Screen Display but now i'm going to be printing a lot and it has thrown up a few issues.

I normally use photoshop with colour management turned off which gave me great consistency from Viz but if I send these to the printer they come back greenish and over saturated.

If I apply an sRGB or Adobe 1998 colour Profile the image on screen turns greenish and over saturated but if I print it more or less matches the screen.

So what do I need to do to get consistency throughout???

I Could convert to sRGB and then play with the colours and saturation to try and match back to what I had originally but I would rather not.

Am I doing something wrong in Vray/Viz or is this a photoshop thing, Anyone any ideas???

I am using what I think is a LWF with gamma correction burned in.

1. Max preferences – gamma display 2.2 & input gamma 2.2
2. Vray: Colour mapping - Gamma Correction - Gamma 2.2
3. Colour Correction Plugin - Gamma 2.2
4. render in Vray frame buffer
5. Save as 8bit tiffs open in photoshop with no colour correction

These settings give me great consistancy between what i see in the viewport to what i see in the frame buffer to what i see in photoshop so ideally i don't want to muck with it. If i have to then i'll just have to because spending days and weeks setting up lighting & textures to display correctly in Viz and then having to go through it all again in photoshop sucks.

All help appreciated.

[GeorgeP]

It sounds like your printer, grasshopper. What is it? Does it have its own colour-management system?

[zeilveen]

And just talk to your guy at your printers, what machine is he using to make the prints on (Canon, Xerox, more) or is this print press where it goes wrong, I had the exact same problem ten years ago and turned out it was the Canon CLC 1100 printer / copier that could not work with my images, their new machine was fine..

[Jerry]

Zeilveen, its easy to blaim GejaH

[zeilveen]

ok ok, we should have used CMYK colours.

WAHAHAHAHA YOU HORSE )

[grasshopper]

Thanks for your replies, I probably should have mentioned that we are out sourcing our printing as the office printer is guff.

I work in an architects office and 90% of there work is plotted so the only colour printer we have is a hp inkjet 2800 which is crap for my needs and produces off colour prints with random lines down them.

When I asked the Company who do our printing about format and colour consistency they said just to flatten the image and do not convert it to CMYK as there machines will convert it. I have sent numerous test images in various formats with & without imbedded ICC profiles and as I said above the only images that come back similar to my screen is if I use sRGB or Adobe 1998 which doesn’t allow for consistency between Viz & photoshop.

I know I may be moaning about having to do extra work but I’m sure there is a way round this.

I will post an example below and hopefully this will show what is going on

http://www.gregsteel.pwp.blueyonder....print_area.pdf

http://www.gregsteel.pwp.blueyonder...._area_srgb.pdf

The first image is with colour management off and the second is with it converted to sRGB which is how it comes back from the printers. The designers are moaning cause they can’t show the clients accurate colour presentations.

Can any one suggest something apart from re-adjusting the colours by eye? or is this the only way?

[glyph]

you've uploaded the same pdf twice!

[grasshopper]

Are you sure because when i view these images the both look different. One has a sRGB colour profile embeded.

[grasshopper]

My apologies.

I've just checked on a colleagues pc and both images appear the same on his screen. He's got a CRT.

I'm using a flat panel monitor.

I've just tried on an other flat panel and they appear different.

Whats going on?

[grasshopper]

On my lap top which obviously has a flat panel they appear the same.

Help!!!!!!!!!!!!!!!!!!!!!!

[jujubee]

So I guess my question is - why are you converting it to sRGB then? sRGB is a monitor space, not a print space. You may want to get into contact with your printer and find out their recommendations.

With some newer photo printers, they have a built in 'dummy' color converter so you can send RGB images directly to a printer and the printer handles the color translation.

Traditionally (and with a lot of presses), they work with CMYK and Pantone - so you would convert and image you had from RGB to CMYK. The CMYK colors will never accurately match up with the original RGB - often you would have to tweak the levels in CMYK to approximate the original RGB (additive) colors. But that's the prefered method. If they have newer equipment, the color matching may already be taken care of.

Most printers however will match what you provide them or do the color conversion automatically for you. I would really consult with them to see what they are working with.

[grasshopper]

Thanks for your reply jujubee. The printer told me not to convert the images to CMYK because the machine would take care of them.

As i understood it and i may be wrong, if i embedded an ICC colour profile there software should be able to read it and convert my colours to as close as possible the colours produced by the printer. This however does not seem to be the case. Am i miss understanding this?

I shall go back to the printers and ask a few more questions but thanks anyway.

[glyph]

yup jujubee is right - I'm from old school print design and I used to convert images to cmyk for print but now it seems a lot of commercial print repro equipment can do a better job - smooth gradients can band sometimes converted to cmyk

Also I had a rough idea of what to do to tweak images for cmyk and how to look at the channels, but once you get to proper print you really need a proper proof first

I was looking at your images with a crt - maybe newer versions of Acrobat Reader can apply the srgb curve?? (no idea which version I use but I've ignored that update button for years!)

[jujubee]

Well - the other thing you have to consider is your own monitor and printer color calibration. They can be significantly off.

[grasshopper]

Thanks guys but after talking to the printer he advised:

Not to assign the srgb profile and then adjusting the colour but to convert it to a srbg profile. this way it converts your current colours and keeps them as near as possible as you move to sRGB.

it seems to have worked there printers will then recongnise the sRGB and convert it to CMYK before printing.

The results are great.

Well - the other thing you have to consider is your own monitor and printer color calibration. They can be significantly off.

your right jujubee my monitor does need calibration but i am still awaiting the sowftware.