Mike Chaney's Tech Corner

Mike's Software => Qimage Ultimate => Topic started by: Jeff on September 11, 2011, 04:46:19 PM



Title: Green cast
Post by: Jeff on September 11, 2011, 04:46:19 PM
I have hit a printing problem with attached image.
 
All the window frame and the model is printing with a green cast.

Checking print to my screen the greenish trees in background are printing ok, but the creamy coloured window frame and model is printing a similar green

I have printed on two grades of paper with custom profiles created by Permajet from my print of their test chart, one print on Permajet Oyster and one on cheap Permajet matt proofing paper both have the same green cast.

Image was a raw developed in QUltimate, then into PS Elements in tiff format, I cloned out some distracting road signs and other rubbish at print bottom (if looked at closely adjustments can be seen).  Saved again as tiff and printed with Ultimate.

I have done this many times before without problem.

I have again looked at video on sel col and fiddled with the green but it is guess work as screen colours are OK.

Image below hope it shows ok, but cannot show the colour error.

(http://jeffmilan.zenfolio.com/img/v27/p124681749.jpg)   


Title: Re: Green cast
Post by: Jeff on September 11, 2011, 04:47:36 PM
Yes that image is the colours I am after.

Jeff


Title: Re: Green cast
Post by: Fred A on September 11, 2011, 04:53:41 PM
Quote
Checking print to my screen the greenish trees in background are printing ok, but the creamy coloured window frame and model is printing a similar green

Dijja do a nozzle check?
Dijja double check driver settings to No Color Adjustment

Fred



Title: Re: Green cast
Post by: Mack on September 11, 2011, 06:43:46 PM
On my monitor, the left side appears warmish (red) while the right side has a cyanish cast (or towards the green too since they are easily confused unless you view them through a "Lee Color Print Viewing Filter" set or the old "Kodak Print Viewing Filter Set" to make the determination.).  A minor change in the QU Color Settings tab makes a big difference too and I work down to the 0.98 level at times to tweak a print.

Northern light window shots causes me headaches as all sorts of colors come in from reflected light.  I see blue sometimes from skylight on an arm or leg more buried in the shadows, and then warm daylight in the most lighted areas, to a color cast off the surrounding frame and paint coloration off the window or room in other shadow areas.

Sometimes the best thing to do is make a copy mask and then grab the paint brush tool, after having a selected color loaded into it that I want, and paint with it at a greatly reduced setting of maybe 5%-15%.  Sometimes I can click on the problem area and mask it and change the Kelvin to get the photo into alignment.

To that end, I made up a large translucent 5x6 foot scrim that I place two high-power 1800 ws studio units behind that drown out any odd color casts when doing northern light stuff.  Might want to bail if it gets too tedious and go to some B&W with maybe a coloration filter you can adjust like in the newer Topaz B&W plugin or similar.


Mack


Title: Re: Green cast
Post by: Winfried on September 11, 2011, 07:21:26 PM
Did you try the softproof-function within Qimage?
Does the softproof also look greenish?
If yes, there might be a problem with profile.

Winfried


Title: Re: Green cast
Post by: Terry-M on September 11, 2011, 09:00:44 PM
Hi Jeff,
Quote
I have printed on two grades of paper with custom profiles created by Permajet from my print of their test chart, one print on Permajet Oyster and one on cheap Permajet matt proofing paper both have the same green cast.
Have you used these profiles before? Have you tried a "canned" profile for these papers to see if you get the same problem?
From what I see on this forum, one common cause of a colour cast is some blocked nozzles. Fred has already asked about a nozzle check. That should be your first port of call along with checking ALL driver settings.
Terry


Title: Re: Green cast
Post by: Terry-M on September 11, 2011, 09:10:05 PM
Me again,
Jeff, I took the liberty of downloading your image and printing a 6x4 on Ilford Smooth Pearl, custom profile for an R800. By Ott Light, it's a near perfect match on colours so there's nothing wrong with the image.
Terry


Title: Re: Green cast
Post by: Fred A on September 11, 2011, 09:43:59 PM
I did exactly the same and got the same result.   
No image problem
Fred


Title: Re: Green cast
Post by: Jeff on September 13, 2011, 04:43:31 PM
Thanks for all the helpful comments.

I had another session on image yesterday morning and still could not find a cause for greenish cast.

Found another image in the sequence where window frame has photographed white and sky is blue! there was most possibility a change in daylight between the two shots.

The shoot was last March so exact details have gone from memory, the location was a local village hall and I wonder if there is some strip lighting messing up the colour balance.

I have looked up the Exif and see Auto WB Daylight iso 200  but no mention if there was fluorescent light involved  :) :) :)

I mostly shoot on Auto WB, save forgetting to reset - memory gain.

Printer nozzle check appears ok.

One interesting point, printer ran out of ink 2" into one of the prints.  CIS system - I reset chips and put the same sheet of paper in.  The paper register was SPOT on, just a darker print when it printed twice.

I would add that to take the shot I was pushing to the limit, exposing for the sky and outside details, the model is very dark and Ultimate gave it a top fill of 20! to recover detail

I will return to print when time available.

Jeff
 
 


Title: Re: Green cast
Post by: Terry-M on September 13, 2011, 05:29:45 PM
Hi Jeff,
Quote
One interesting point, printer ran out of ink 2" into one of the prints.  CIS system
Doesn't it tell you when ink is low? Using Epson cartridges I've had the odd occasion when I let it go too far  ::) and changed mid print and finished the print without any problems at all. I don't do that any more, let it go too far that is  ;)
I still think you have a dodgy ink flow  :o
Quote
I mostly shoot on Auto WB, save forgetting to reset
That's ok as long as you WB when processing the raw. Photograph a grey card in tricky situations, I always carry one, they are inserted in my lens caps - a trick Mike mentioned many moons ago.
I agree, the window frame does have the look of fluorescent light about it but it's quite subtle.
Terry


Title: Re: Green cast
Post by: Jeff on September 14, 2011, 07:25:29 AM
Hi Jeff,
Quote
One interesting point, printer ran out of ink 2" into one of the prints.  CIS system
Doesn't it tell you when ink is low?


Yes, I can see the inks getting low. But I don't find resetting the chips easy, so tend to shy off and leave it to last minute.

However, this time I used a pair of long nose pliers to reach in to the print head carrier and got a first time success.

A couple of months ago I did a print of B & W and that had a green cast, I wonder if that is an indication of a fault.
Is there a specific ink colour that could be causing the problem?

Getting ready - rearranging the "computer room"  for a new custom build win7 64bit so after holiday and new installation I will give all the ink lines a full purge with the syringe, that will be a messy job for October.

Thanks again

Jeff