Web Analytics
Re: HDR question

Re: HDR question


Art Adams <art.cml.only@...>
 

This is correct from an engineering standpoint. From an artistic standpoint... not so much.

There's a difference between capturing images and creating visual stories. For the former, a chart is an absolute reference. For the latter, it's a tool meant to create a consistent starting point when imposing an artistic vision, and ensuring that vision is the one that reaches the audience. 

A chart is not necessarily an image reference, but can be a look calibration reference.

--
Art Adams
DP
San Francisco Bay Area



On Mar 17, 2018 at 11:06 AM, <Alister> wrote:

Geoff wrote:

I have to disagree with you on this Alister, because of gamma and the responses of displays the total range may be the same but the way it is represented can be totally different.
 
I really hope they aren’t different. What would be the point of my expensive DSC Charts?

Sure, it can be different, but it doesn’t have to be, it all depends on the grade. If the camera and monitor gammas are properly matched then capture and display range should also be matched. The engineers didn’t spend decades developing different gammas to make the pictures on monitors look different to the scenes we are shooting. They were developed to make them look the same. If you use a real 709 gamma curve in a camera and have a correctly matched 709 gamma in the monitor then the contrast range of what the camera captures should be reproduced on the monitor with the same contrast and it should look the same. Have you never shot a DSC chart while looking at a 709 monitor and noticed how when it’s all working correctly the chart on the monitor looks just like the chart you are shooting? Both the total range and the contrast range are the same, so they look the same because the monitor output mirrors the light being reflected from the chart. Of course you can screw this up by doing this on a bright sunny day where a 709 monitor has no chance of reaching the same output levels as a chart illuminated by direct sunlight, but do it under controlled lighting where the lighting does not exceed the monitor output and both should look near identical, if they didn’t charts like the CamBelles would be pointless.


Alister Chapman

DoP - Stereographer
UK Mobile +44 7711 152226
US Mobile +1(216)298-1977


www.xdcam-user.com    1.5 million hits, 100,000 visits from over 45,000 unique visitors every month!  Film and Video production techniques, reviews and news.

















On 17 Mar 2018, at 13:42, Geoff Boyle <geoff.cml@...> wrote:

I have to disagree with you on this Alister, because of gamma and the responses of displays the total range may be the same but the way it is represented can be totally different.
 
Cheers
 
Geoff Boyle NSC FBKS
Cinematographer
Zoetermeer
+31 (0) 637 155 076
 
So if a monitor can manage 8 stops and the scene is 8 stops and if the brightness of the monitor can match the brightness of the scene, in the same environment both will look the same. 
 

Join cml-raw-log-hdr@cml.news to automatically receive all group messages.