Digital Printing
see also:
print paper/canvas:
Canson / Arches distributed in Australia by Arjowiggins in Victoria
GicLee media supplies - inkjet canvas, fine art papers
Introduction:
printing digital images involves several steps:
decide on what printer & paper you will print to as this determines how you will proceed:
you may need to assess your image for ability to crop to the appropriate image aspect ratio and size.
will you require fine detail, high dynamic range fine art monochrome print? then use Ultrachrome ink on high gloss paper or on a new baryta paper such as Ilford Galerie Gold Fibre Silk.
is your image a mood scene that would print best on a textured surface or a canvas?
in general images with smooth tonal areas are better on smooth papers rather than textured, and thus smooth paper is probably a safer choice for most images.
for fine prints, the heavier the paper the better (eg. 300gsm), and many use archival quality cotton rag papers for matte or the newer baryta papers for higher DMax and extended color gamut in the deep blues and greens without being too glossy (eg. Ilford Galerie Gold Fibre Silk).
see also:
decide on color space of image, monitor, image editing tool and printer:
most cameras use sRGB by default so unless you shoot with medium format digital backs or your printer requires it, most people would use sRGB as that is what their monitor will display.
as yet there are no monitors that have a color space the size of the AdobeRGB space.
most consumer printers require it in sRGB, but if sending it to a magazine or graphic designer they may need it in AdobeRGB.
Abobe RGB (1998) has a wider gamut than sRGB, in particular, it can contain colour data for richer cyan-green midtones, orange-magenta highlights, or green shadows than can sRGB, but unless the printer can print the extended gamut (eg. newer high end inkjet printers), you may still be safer just using sRGB.
if using a commercial printer, you may need to consider converting to duotone or variant:
although an 8-bit gray scale jpeg image can hold 256 gray tones, commercial CYMK printers can usually only print up to 50 gray tones.
to get around this, you can convert your image to 8bit grayscale in PS then convert to a duotone (2 inks used), tritone (3 inks used) or quadtone (4 inks used) which allows increased tonality in the print.
ensure your computer monitor and software is colour calibrated so that you can best judge how to edit your image for the effect you want - see color calibration
before you go and start changing colours in your image, check that you are not colour blind or you may end up with results that look good to you but may not be as good to the remaining 95% of the population.
process the RAW image
consider adjusting curves to ensure adequate dynamic range is captured:
recover burnt out highlights:
eg. use recovery setting in PS CS3, or try settings such as:
recovery = 0; exposure to a negative value as needed; blacks = 0; brightness eg. +50, contrast eg. +38; fill light as needed for shadow detail; tone curve = strong contrast;
recover dense shadow regions:
even using Ultrachrome K3 inks on matte paper, shadow details will not be obvious when pixel values are below 12-15 on a 0-255 scale (ie. 8bit).
eg. use "Fill light" setting in PS CS3
then use Camera Raw Parametric Curve function
consider applying a small amount of "capture sharpening" on the RAW file to compensate for blurring due to the anti-alias filter (ACR v4.0 and Lightroom v1.1 and higher have this facility)
consider using DxO Optics Pro 3.5 software to minimise mosaic artefacts before creating a 16bit TIFF
edit the image to the desired effect:
clone out any undesirable features
consider using LAB color mode to adjust colours/contrast if image looks dull with lifeless colors or limited color range.
consider adding hue to blown areas using LAB color space:
consider improving portraits:
consider adjusting levels:
Image/Adjustments/Levels move left slider to left edge of histogram, move right slider to near right edge of histogram and adjust middle slider for desired contrast effect.
consider adjusting saturation
consider reducing fog/haze:
Filter/Sharpen/Unsharp mask. Apply the following settings: Amount 60 Radius 20 Threshold 0.
consider improving skin tones:
Image/Adjustments/Selective Color choose red channel and move Cyan slider to minus 20 to minus 40.
consider adding vignetting effect:
use burn tool, set to soft brush at larger than image size, and 20% exposure, first do highlight setting until can just see a darkening, this sets the scene for re-doing it with the mid-tone setting.
consider adding some "creative sharpening"
crop &/or resize image to the desired print size at the printer's dpi output
can use Photoshop's crop tool and preset it to the final print size and required dpi.
http://www.cambridgeincolour.com/tutorials/digital-photo-enlargement.htm - some nice calculators & demos of different resizing algorithms such as bicubic or fractal interpolation.
minimum required print ppi depends upon viewing distance from print:
25cm => minimum of 350 ppi preferable
50cm => minimum of 175 ppi preferable
1m => minimum of 90 ppi preferable
some find better results on resizing by using either:
apply final sharpening AFTER final image resizing for printing
historically, this was done using PS "unsharp mask" or QImage's equivalent, but now many use PS CS3's "Smart Sharpen" tool
consider applying USM in luminosity channel in LAB color mode to avoid color artefacts from sharpening.
see tutes on using USM:
http://www.dgrin.com/showthread.php?t=9541
view image at 100%
set amount to 500%, radius to 5 and then adjust threshold so noise is not accentuated
then reduce radius so halos do not obscure detail (usually to 1-3 for a 8mp image)
then reduce amount to give best effect, usually when halos no longer visible but their effect is.
consider adding a final noise to give a little texture
Filter/Noise/Add Noise, and set the amount at 1
save file as per printer requirements eg. 8 or 16bit RGB TIFF (maybe needed to be in MAC format)
the print when viewed under daylight conditions should closely resemble what you saw on your monitor.
Colour calibration:
Final, pre-print sharpening:
Photographic Printers:
Viewing monochrome prints: