<filename>files/json/reply_20040512_1935_radiance-general_001691.json<gh_stars>0
{"body": "Hi Alexa,\n\n\n>> ...\n>> However, I think others will agree that pcond can be useful, and is \n>> an improvement over the standard \"linear with clamping\" method for \n>> image display.\n>\n> I don't doubt that it is better for image display and I think the idea \n> with these kind of mappings is to go down the route of 'perception' \n> rather than 'physics', one reason being the current limitations of \n> CRT's e.g.\n>\n> My concern is physical accuracy. I want to display an image on a \n> screen (eventually) and people should not be able to tell it apart \n> from the real world scene. Of course, I can only simulate colours and \n> luminances that my daft 8-bit monitor can actually render.\n\n\nThere are surround issues to consider as well, especially since the \nmonitor only covers a small portion of your view.  Pcond attempts to \nadapt the original scene levels to the current viewing environment -- \nsomething not even an HDR display can do.  You need something like the \nwide-field HDR viewer I built to test out tone operators for that.\n\n\n> Talking about the limitations of CRT's. Has somebody seen \n> DLP-technology displays in action and maybe even made some colour \n> measurements? Apparently, the colour resolution can be cranked up to \n> 15 bits per channel and the luminance range is also much bigger. I \n> only wonder, if the 15-bit resolution per channel is actually really \n> an improvement in terms of colour resolution for a given luminance \n> level (in comparison to a traditional 8 bit resolution)  or is \n> basically necessary to cover the increased luminance range?\n\n\nIf the 15 bits is in a linear range, and a DLP is a linear device, then \nyou don't actually gain much in terms of dynamic range over an \n8-bit/primary encoding using a standard 2.2 gamma.  Beware of \nmanufacturer's claims regarding contrast ratios and bit depths.  There \nare no standards, and the marketing people have a field day with these \nspecs.  Bottom line:  don't trust it unless you've measured it \nyourself.\n\n\n> Is that the same technology used in last year's emerging technology \n> SIGGRAPH session:\n> <NAME>., <NAME>., <NAME>., <NAME>., Ashdown, \n> I.,\n> <NAME>. and <NAME>., 2003, High Dynamic Range Display System. \n> SIGGRAPH 2003, Emerging Technologies Program.\n> http://www.siggraph.org/s2003/conference/etech/hdr.html\n\n\nWe actually have a full-blown paper in this year's Siggraph, which is \nnow online as well at Wolfgang Heidrich's website if you're interested:\n\n\n\thttp://www.cs.ubc.ca/~heidrich/Papers/index.html#siggraph\n\n\nThis is a very cool device, but is only available in limited quantities \nas a prototype to select companies and individuals.  Sunnybrook \nTechnologies (http://www.sunnybrooktech.com/ Vancouver, BC) hopes to be \nmanufacturing the real deal by next year.  As I said, even an HDR \nmonitor doesn't deal with surround issues, so it's really quite \ndifficult to reproduce the visual appearance of the real world in all \nit's glory.\n\n\n-Greg\n___\n<sup>Automatically generated content from [radiance mailing-list](https://radiance-online.org/pipermail/radiance-general/2004-May/001691.html).</sup>", "attachments": [], "created_by_name": "<NAME>", "created_at": "May 12, 2004 at 07:35PM", "created_by": "Greg_Ward", "parent_id": "radiance-general_001679", "id": "radiance-general_001691"}