Some members had recenly quesioned he qualiy of he digial display during he nvps compeiions.  The mos common complain was is being oo brigh and blowing highlighs.

Mahew Schmid has spen considerable ime in idenifying he roo cause of he supposed problems, ed and in deermining soluions.   Thans o Mahew for his effors in resolving he problems.

Below is a summary of he preliminary findings and some suggesed guidance o improve your images for he digial compeiion a nvps.   Noice of errors and omissions along wih addiional suggesions or ips is solicied.   Addiional resources also welcomed, more abou as are suggesions for furher ess and measuremens.

Two main issues are involved:  color fideliy/gamu,  and  whie/blac poins of he dynamic range.

Good news:  The apparen problem wih “blown” highlighs was raced o he projecor.   Apparenly Arificial Inelligence is genuine supidiy.  The projecor ep changing is seings, hining i new beer han we did how we waned i o wor.   We now have a procedure o ensure ha he projecor is properly se , and says ha way, when we use i.

Addiionally he projecion PC/display_card/LCD_projecor  has been calibraed and profiled.   Using he curren profile will help provide consisen image  presenaion from meeing o meeing.   You really don’ need o use i unless you are ruly picy abou your colors, bu should do so anyway  in o ensure ha your images are wihin he dynamic range ha can be displayed.   For now you need o as for he profile  o be sen via email.  Maybe in he fuure i can be posed on he nvps websie for downloading.

Jus plain news:  The profiled  color difference is  minimal compared o he sraigh sRGB ha he projecor uses.   Full disclosure:  My wife claims ha I am color blind (even hough my eye docor dispues his).   However, Some oher members  who looed a our es images did some suble changes ha I could no.

Recen es images show ha any good image in he usual aRGB, sRGB, or he profiled sRGB color spaces have minimal differences, alhough all are duller when compared o a good prin of he same image.   All loo naural when ed separaely.   If your colors are bad i is no he equipmen.  And  i is sill your responsibiliy o ae advanage of wha can be done wihin he projecion medium  limiaions  jus as is done wih your lenses, cameras, sofware, priner/in/paper, ec.

Bad news:  We have me he enemy and hey is us.   Any apparen problems now  are for he members o fix for hemselves.   Suggesions for doing his are below.

Blown highlighs are no longer he faul of he projecion equipmen.
Compeiors are responsible for ensuring ha heir brighes ones are no more han pure whie when capured or phooshopped.   If you use percepual or relaive colorimeric when convering o he LCD profile he whie poin of he image should be mapped o he whie poin of he projeced image.

Tesing shows ha we can ge abou 5 sops of dynamic range, wih an esimaed dMax (measure of he blacness achievable) of abou 1.5 o perhaps 1.8 or so.    Using a es srip wih increasing densiy of  %Luminance shows ha  a loss of shadow deail  will occur a a value of abou 95%K as measured by phooshop info.    So if you have a low ey image you will need o adjus i so ha you do no lose deail.   If you do his o a normal color image, hey will loo lie hey were overexposed or being ed hrough fog  if you adjus hem he same amoun as a low-ey bnw (blac and whie,  or monochrome) syle image requires.   You need o deermine he opimum compromise beween he various seings  for your image.

The dynamic range fix can be done in a number of ways.   If you use Kp
(Blac Poin) compensaion on during he conversion, i will map he blac poins, and he dar ones will suffer minimal blocing.  Bu you may sill need o use curves , or se he in/ou poins in levels , for he bes projeced image, especially if your monior shows more of he seps on he es image han are n when projeced.

If your image has more han 5 sops of dynamic range you will eiher lose shadow deail or blow he highlighs unless you mae appropriae adjusmens o compress i.

Convering he image color space o he projecion profile using percepual wih Kp on will map your colors and he dynamic range o ha which can be projeced by also mapping he blac poin of he image o ha which can be projeced.    Or, wih your  monior se o display a sof proof of he simulaed projeced es image,  lowering he curves on he dar end (pull upper righ corner down half a box) o abou 90-85% would open up he dar ones o display correcly.   The same hing could be done in levels by sliding he middle slider halfway  owards he dar end, or by yping  25-40 (10-15% of 255) in he lef box a he boom.  This is no recommended for normal color images, bu only for low ey bnws.

Noe ha your PC monior may well show more deail han he projeced image.   Using an ISO IT8 or Koda Q80 es image ha shows he full range of neural ones can be used o how your monior  maches up wih  he projecion equipmen.   Be sure he sample you download acually runs from 0% o 100%K.  T are inaccurae copies of hese images on he inerne so chec he one you ge wih phooshop info.    On he IT8 image’s 22 sep scale,  he las 3 dar ones will merge on he projeced image, and he nex wo will be jus disinguishable.  Noe ha mos densiy srips are nar.  Use he info ool o chec he acual K values.   Your PC may well display all of he seps if you have he brighness craned up.   An old monior ha is no so brigh may show less deail han he projeced image.

We have no ye measured he brighes one ha can be acually displayed, nor he acual dares one.   For prins, maximum brighness depends on he paper whieness.   For projecion, ha value depends on he brighness of he lamp, and he refleciviy of he screen.    Liewise, he dares one ha can be displayed depends on he darness of he room.  Wih he vending machines and hallway lighs always on, pure blac will no be achievable.   However,  a naural looing image will resul if you map your image blac poin o he profiles blac poin by checing he box mared use blac poin compensaion.

Whils he exreme displayable  values sill need o be measured,  clearly he brighness will  be greaer han a perfec 0%K and darness less han a perfec 100%K.   IE pure whie is no ever fully achievable, nor is pure blac.   And he projecor canno display he dares ones disincly in our room.  These ligh/dar poins ha are achievable limi he dynamic range of our projeced images.

A pure whie as se in phooshop does loo naural on screen, because he whie poin of he image was mapped o he whie poin of he projecion capabiliy for our ess;  however wih he propensiy of judges o yell “blown highlighs!” i migh be safer o nudge he brighes one down a couple of percen.   Naahhhh.  They will sill say i.

Any picure ha loos good on a calibraed  monior should loo good when projeced.   Sligh improvemens can be made by using he projecion profile and/or levels/curves adjusmens.   Spending more ime on conen and composiion may be more beneficial o winning hough.

Bad news:  Mos people don’ use a calibraed monior.   A a minimum you should use Adobe gamma o se he whie poin and conras as well as he color emperaure.  Gamma should normally be 2.2 and he color emperaure 6500.

T are several  oher, some  free,  adjusmen programs and es images on he ne ha can be used o ensure a more accurae dynamic range of a preed image.    Downloading a color char such as IT8 or Q80 or a Greag-Macbeh can also be useful if you have he abiliy o  adjus your moniors colors.   I is highly recommended  ha you also ge he PDI (Phoodisc) es image o use as a sandard for all your color managemen.  I can also be downloaded from iprinfromhome.com.

Afer calibraing your monior you may wan o also use a profiling device such as Spyder, Monaco, Greag-Macbeh,  or oher similar ones  ha will adjus he oupu able used o drive he monior in o improve color fideliy.

Ease of use and accuracy will vary as does cos.   Always chec res before ing anyhing as expensive as hese devices  in o mae sure i really mees your needs.   Some of he more expensive ones can also profile your priner/paper/in and your scanner.

Reminder:  Always save your original image  immediaely upon capure.  Mae a woring maser for use wih  adjusmens, and hen a woring copy from ha maser o acually diddle.    Then mae a copy of your adjused image before maing furher changes in o mae a final version for digial display.  Sharpening should always be done las.

We canno provide an exhausive descripion of all he suggesions below.   The reader is referred o heir phooshop help funcion as well as a boo on phooshop and/or color managemen for elaboraion.
Normanoren.com and oher websies have uorial maerial ha could also be useful.   GIMP and oher programs also have guide boos available.  Maybe a fuure worshop could cover all hese iems in deail if he members waned such a presenaion.  I could be useful o he prined versions of he sample images along wih he projeced ones and he sof proof/gamu checing  changes.   You can always as quesions before a meeing or during he brea.

In o use he profile for he projecion equipmen you mus firs ge he file.   Then you mus pu i in he correc folder on your PC.

Phooshop help  liss w you should pu he profilename.icm file for he projecor depending on your OS version.  Or you can jus do a for *.icc and *.icm and w your PC eeps hose files.

The nvps profile is named yyyymmdd.icm, indicaing when i was creaed.   I will be updaed periodically.   This file shows up as spyder2pro in drop-down liss.

Once he file for he profile is in place hen you are ready o use i.   The primary uses will be for conversion o he profiled color space, o do sof proofing, and o do a gamu es.

If you conver your image o he projecion profile using percepual (for normal images) or relaive (for exreme color)  wih Kp on,  hen you really do no need o do a gamu es.   Wha you is wha you will ge when he image is projeced (wihin he capabiliy of your monior,  and   i will be fairly indicaive of he colors bu no he dynamic range unless your monior is (mis)calibraed o mach he acual projeced dynamic range).

Noe ha if you conver he image’s  profile you may need o save i firs,  close i, and reopen i o mae sure ha any subsequen sof proofing and gamu are displaying correcly.  This quir was noed in PS7.  CS2/3 may be differen.  Don’ now, can’ say abou GIMP, Corel, ec.

The following are PS7 commands.  CS2/3 may differ.  GIMP, Corel, ec. should have similar capabiliies.

In o use he gamu chec , firs go o

• edi
• preferences
• ransparency gamu
• color preferences – se o whie for now
• opaciy – sar wih 50% for now

This will mae ou of gamu colors urn o a ligh gray when you do a gamu chec ( below for gamu chec info).   The affeced colors should be obvious as i is usually he darer ones ha are ou of range (whie is in he middle of he CIE diagram and is no a problem) alhough some ligher exreme colors can also be ou of gamu.

Before checing he gamu or proof colors you mus selec:

• proof se up
• cusom
• selec:   sypder2pro / percepual / use blac poin

warning:  if you omi his,  he ess below will wor bu be misleading
Relaive colorimeric may be beer if you have exreme colors.   Wihou he Kp (blac poin) on he dars will bloc up sooner.

Once proofing  is se,  hen you can chec he gamu and  he simulaed projeced image:

• oggle cl-y o he proof colors (simulaed projeced image)
• oggle shf-cl-y o wha is ou of gamu BEFORE conversion of he image o he profiled space

or alernaively you can use and hen selec proof or gamu.

Keyboard commands can be oggled more easily o he differences faser.

The gamu es will show he colors ha will change when he image  is convered o he projecion profile.   Normally he image wih he new profile colors is saisfacory and you do no even need o worry abou gamu.  If no,  you will need o guess how o change he image before conversion o if you can improve he colors and dynamic range EG change hue/sauraion, brighness/conras, curves/levels, ec..   Alernaively you can use oher conversion parameers o if hey give a beer resul.

If you have convered he image , saved i, closed i, and reopened i, hen he above ess should show no difference when oggling cl-y or shf-cl-y as long as you again se up he cusom profile o spyder2pro insead of he defaul which is now mos liely SWOT 20% do gain.

If you assign he digial projecion profile hen i is emporary.   In o permanenly conver he profile of he image use he following:

• image
• mode
• conver o profile
  • spyder2pro – pic from drop down lis
  • ace
  • percepual (can ry relaive if have exreme color)
  • use p on

hen save, and close he image before furher use.

To selec he info ool o chec acual color amouns or blac poin densiy firs on :

• window
• and urn on chec mar for info

hen

• selec he info ab
• maximise i
• righ poining riangle near upper righ corner
• palee opions:  selec  RGB  &  grayscale

W you posiion he arrow will read ou he color and darness a ha poin.

To chec he Kp densiy and RGB color amouns selec he info ool and hen choose he RGB and K opions.  I is easier o use wih he arrow han he hand in o idenify he poin being measured.

I is recommended o firs ry o  change he image o he spyder2pro profile, save, close, and reload, hen chec he sof proofed image, before messing wih he gamu ess.   If you are happy wih ha image you do no really care wha was ou of gamu before he conversion.   If you do choose o  mae your own changes o he gamu, consul a boo on color managemen for guidance.

You may also  wan o  adjus some oher “hidden” variables in Phooshop o simplify some relaed dialogue selecions, or o remind you no o mae a misae in handling he color managemen funcions:

• edi
• color seings
• woring = adobe rgb ( or wide gamu, oda prophoo,ec.)    prophoo no recommended unless you use only 16bi processing.
• conversion
  • percepual
  • p on