Path: csiph.com!xmission!news.alt.net From: dale Newsgroups: rec.photo.digital,sci.engr.color,sci.image.processing Subject: Re: ICC profile for a light box Date: Sun, 5 Aug 2018 14:31:18 -0400 Lines: 101 Message-ID: References: <250720180738159630%nospam@nospam.invalid> <0001HW.210FE5460028FC0270000C8932CF@news.giganews.com> <0001HW.210FE5DC00291F0B70000C8932CF@news.giganews.com> <300720182157009140%nospam@nospam.invalid> <0001HW.2110954600523BA87000010092CF@news.giganews.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 In-Reply-To: Content-Language: en-US Xref: csiph.com rec.photo.digital:219929 sci.engr.color:1152 sci.image.processing:4391 On 8/2/2018 3:48 PM, dale wrote: > On 8/2/2018 4:54 AM, Martin Brown wrote: >> On 01/08/2018 01:24, Eric Stevens wrote: >>> On Tue, 31 Jul 2018 06:01:58 -0700, Savageduck >>> wrote: >>> >>>> On Jul 31, 2018, dale wrote >>>> (in article ): >>>> >>>>> On 7/30/2018 9:57 PM, nospam wrote: >>>>>> In article, dale >>>>>> wrote: >>>>>> >>>>>>> might be a nice feature for Lightroom ... compatible with some >>>>>>> measurement instruments ... and data like viewing angle, white >>>>>>> point, etc. >>>>>> >>>>>> lightroom has been fully colour managed since day one. >>>>> >>>>> there is a difference between managing color and managing appearance, >>>>> look up CIECAM02 on wikipedia >>>>> >>>>> viewing environment like a light room is one variable in appearance >>>> >>>> What exactly do you believe is a *light room*? >>>> >>>> Understand that any viewing environment is going to be influenced by >>>> amient >>>> light, regardless of the specific light source be it day light, or >>>> any type >>>> of artificial lighting. >>>> >>>> What is your specific, or special purpose/interest for needing this >>>> specific >>>> icc profile for a *light room* (not LR the app)? >>>> >>>> It doesn’t sound as though you have any interest in color management >>>> for >>>> photography post processing. >>> >>> My impression is quite the contrary. Why else do you need color >>> management if it is to enable the management and control of the >>> appearance of the finished print? The process starts with the object, >>> continues through the camera, the processing in computer (which >>> includes the screen or monitor), on through the printer and paper and >>> surely (and this is the subject of the OP's original post) includes >>> the viewing environment. >> >> Provided that the light approximates a blackbody with a characteristic >> temperature then the human eye's automatic white balance does a very >> good job of removing the orange or blue casts that a camera will >> faithfully record (if it is set to record the absolute RGB image). >> Remember in the old days of daylight vs artificial light films? >> >> You cannot control the lighting environment that prints will be viewed >> in and some peaky LED or mercury line fluorescent lamps can mess stuff >> up. But if you avoid the obvious pitfalls then comparison by eye with >> the original object is OK under real incandescent light or sunlight. >> >> There are a handful of materials whose colours alter radically >> depending on the colour temperature of the light that they are seen in >> didymium glass being one such and the gemstone Alexandrite another. >> They are unusual in that they have a deep cut notch in their >> transmission spectrum in the yellow which makes their perceived (and >> measured) colour vary significantly with the ambient lighting >> characteristics. >> >> https://en.wikipedia.org/wiki/Chrysoberyl#Alexandrite >> >> Most pigments and dyes used in colour printing avoid having these >> characteristics to prevent a print from appearing significantly >> different depending on the colour temperature of the ambient light. >> >> You still have problems in a mixture of incandescent and daylight >> though if the proportions vary across the object. Compared to the >> subjective errors caused by well known optical illusions there is >> little point in obsessing about total control of everything for one >> particular lighting situation unless you can control the display >> environment precisely. >> > > you *can* control the viewing environment an image is "approved" of ... > > ... WYSIWYG ... > > soft proofing from monitor to print in a light box, light room, or > transparency on light table sometimes involving a loop ... or the > reverse involving scanning or camera capture > > ... hard proofing more applicable to prepress... > > you sound like you would rather put the emphasis on the hardware, which > would be "good enough color" with a standard working space like sRGB > which has proved out for consumer WYSIWYG as in W3C's choice > there are also hoods for monitors ... -- dale - https://www.dalekelly.org/ Not a professional opinion unless specified.