# eciRGB_v2 - the update of eciRGB 1.0 - Background information

The eciRGB_v2 profile is a **technical revision** of ECI’s
existing RGB working colour space profile eciRGB 1.0. Currently ECI
is submitting eciRGB_v2 into ISO standardization such that it is
expected to be incorporated – including a complete and detailed
specification of its characteristics – into the **ISO 22028**
series of standards. For ECI this is an important step in order to
further extend the already wide spread use of the eciRGB profile -
the publication as an ISO standard will establish it as a worldwide
RGB standard profile for use as a working colour space in the
graphic arts industry.

The **most relevant improvement** is that luminance is now encoded
in an equidistant way – ‘conversion losses’ between data and the
human eye are thus a matter of the past: The gamma of 1.8 has been
replaced by an L* characterization as used in the theoretically
ideal CIELAB color space. This improved encoding efficiency brings
with it substantial advantages in the shadows, as the risk of
posterization effects – especially while retouching – is
significantly reduced. Errors caused by colour space conversions –
e.g. banding or reversal – are minimized as much as currently
technically feasible.

The focus of the eciRGB_v2 profile still is on the
**print and publishing industry** – the gamut of the eciRGB_v2
profile as well as its white point are identical to ther gamut and
white point of the original eciRGB 1.0 profile.

In general, ECI now recommends to always use the eciRGB_v2 profile
for new projects or when creating new data. This is especially true
when converting from RAW data or from 16 bit image data.

For **existing projects** and files which are not using eciRGB_v2
it is not recommended to convert them to eciRGB_v2 in order to
avoid unnecessary conversion or – even more dangeorus – assigning
the wrong profile to the data. Especially 8 bit data using eciRGB
1.0 should be kept in eciRGB 1.0 (preferably with the eciRGB 1.0
profile embedded) as any colour space conversion will lead to at
least some loss of quality.

If you still have the need to bring your old data into the new
colour space you have to perform an ICC profile conversion to the
new eciRGB_v2 profile. Do not just “assign” eciRGB_V2 as the
source profile, as it will lead to color and luminance shifts. As
already mentioned before, there is no technical reason to do so.

eciRGB_V2 is avail able for free and can be downloaded from our
**Download** section.

# What is eciRGB 1.0, and why should I care?

eciRGB 1.0 is recommended by the European Color Initiative (ECI)
for use as an RGB working color space and color data exchange
format for ad agencies, publishers, reproduction and printing
houses.

There are a couple of aspects that led to the development and
release of eciRGB by the ECI in 1999: - Up to Adobe Photoshop 5.5
the default for the working color space was the monitor profile of
the computer on which Photoshop was running. This turned out to be
a less than perfect approach, as every computer may have a
different monitor profile, and a working color space should not
depend on what happens to be the monitor profile on a given
computer, but should always be the same, at least within any given
workflow. - Furthermore a monitor profile typically does not cover
certain ranges of colors that can easily be produced on a printing
press - the major area of weakness of a monitor compared with a
press is in the Cyan color region. - Staying in the scanner
profile’s color space often makes no sense, as a scanner’s color
space typically is not very uniform (a characteristic offered for
example by the Lab color space) this makes them unsuitable for any
corrections or editing. - Lab in principle looked like a good
alternative candidate, but hardly any widely used software (until
maybe very recently) supported editing and retouching for 16 bit
Lab data or import of 16 bit Lab images (and while PostScript/EPS
supports up to 12 bit Lab data, in PDF 16 bit image data have only
been introduced very recently in version 1.5, earlier versions only
accommodating a maximum of 8 bit), and 8 bit Lab data was far too
inefficient, as only less than a third of all possible Lab color
values actually occur in real world color data: which means that
out of the 8 bit only a bit more than 6 bit would actually be used,
which simply isn’t enough. Even with 16 bit Lab the issue arises
that it uses twice the amount of data - while the increase in file
size often will be moderate due to compression, the amount of RAM
needed definitely doubles. - while there were and still are other
reasonable offerings around in terms of RGB working space ICC
profiles ECI wanted to see one that … has a gamut that covers all
colors that can be printed on today’s printing presses - whether
sheet fed or web offset, gravure or newsprint - but not much beyond
(in order to not to waste precision for bits that never really get
used) … produces a neutral gray whenever the values for Red, Green
and Blue are equal … offers equidistance, i.e. equal difference
between two color values in eciRGB mirrors an perceived equal
difference when these colors are seen by the human eye … is based
on a Gamma of 1.8 and a light source of 5000K. This profile was
created and tested in 1998 and provided to the public free of
charge in early 1999. Most ECI members have meanwhile based their
internal workflows on eciRGB as the preferred (and often the only)
RGB working color space, and have been more than satisfied with the
advantages achieved.

Is eciRGB the only working color space that makes sense? Definitely
no. Other experts and user groups in the industry as well as
vendors have been working on this issue and have come up with
alternative options that may work as well as eciRGB. If you happen
to have been working with let’s say Adobe RGB or ColorMatch RGB
until now, it would not be a good reason to convert your image
database to eciRGB just for the sake of then having eciRGB data.
Nevertheless, when you are about to set up a new print oriented
workflow, the ECI is confident that there are hardly better options
than eciRGB (though possibly quite a few that are comparably
good).

How does eciRGB compare to sRGB? sRGB has seen excessively wide
use, as especially HP and Microsoft were promoting it as the
standard RGB profile (in the end often going so far that they -
whether directly or indirectly - propose not to use any ICC
profiles anymore but instead to simply implicitly store and
exchange any RGB data as sRGB. More and more digital cameras, low
end inkjet printers and even monitors now simply assume sRGB. While
this may look like a smart move, it must not be forgotten, that
sRGB as a color space has serious weaknesses - there are a lot of
colors today’s printing presses as well as other output devices
like photo printers, large format printers and many inkjets (not to
speak of up to date monitors or digital cameras) can produce that
cannot be stored in sRGB. If quality is important, sRGB is not an
option.

Should I get rid of my scanner profiles right away and use eciRGB
instead? No, definitely not. Simply assigning eciRGB instead of the
specific profile e.g. for a scanner is one of the worst things you
can do. Always use the correct source profile for the data at hand,
and then convert from that color space into eciRGB.

Note 1: What’s a working color space anyway? The short answer is,
that such a color space is good for working on an image (or rather
any color object), whether color correcting or retouching it or
editing it in any other way. A working color space can be made such
that it is independent of idiosyncrasies of a specific device (e.g.
it can be made uniform to preserve detail equally well in each area
of the color space). At the same time it can be made such that it
serves a class of color spaces well, e.g. that it comprises all or
most of the colors that can be output with all monitor and printing
devices that are available today.

Note 2: In ISO there is currently work underway - as ISO standard
“ISO/CD 22028-2 Photography and graphic technology - Extended
colour encodings for digital image storage, manipulation and
interchange - Part 2: Reference Output Medium Metric RGB colour
image encoding (ROMM RGB)" - to possibly arrive at a working color
space that is even better than eciRGB or other widely used working
color spaces.
