[Radiance-general] Faulty fisheye HDR, DGP always 1.0

[Greg Ward]

Hi Raghu,

What you say does not jibe with what ximage or Photosphere report when probing your HDR image.  The values are all quite high for an interior space.  What program are you using to look at your result?

Cheers,
-Greg

> From: Raghuram Kalyanam <kalyanam at rhrk.uni-kl.de>
> Date: February 6, 2018 9:57:53 AM PST
> 
> Hi Jan,
> 
> We did the calibration and the results of spot luminance measured and calculated from HDR for the light source (calculated with custom made tool )  is very close. 
> 
> I want to compare the measured  Vertical eye illuminance with the one calculated with evalglare, but the results are out of bounds from evalglare, so i couldn't even compare. 
> 
> Could you suggest me anything  else i should be taking care of? Any ideas. 
> 
> Best Regards, 
> Raghu
> 
> 
> 
> On Feb 6, 2018 6:24 PM, Jan Wienold <jan.wienold at epfl.ch> wrote:
> was it taken on mercury ? ;-)
> the luminances are far off... it sums up to more than 600000 lux 
> Jan 
> 
> 
> On 06.02.18 18:18, Greg Ward wrote:
> Hi Raghu,
> 
> We may need to wait to hear from Jan or someone who understands evalglare better than I do.  I don't think there is a problem with your HDR image as you generated it.
> 
> -Greg
> 
> From: raghuram kalyanam <kalyanam at rhrk.uni-kl.de>
> Date: February 6, 2018 9:05:41 AM PST
> 
> Hi Greg,
> 
> I added these options while passing to evalglare like below.
> 
> evalglare -vta -vh 180 -vv 180 <hdr file>, and it worked but it always gives 1.0 as DGP (even other parameters are out of bounds).
> 
> With out those options evalglare throws an error.
> 
> Apart from that
> 
> Are all the LDR’s provided, valid to combine into HDR?
> 
> I doubt if one or more of the LDR’s is the culprit (especially something to do with over or under exposure).
> 
> Best Regards,
> Raghu
> 
> On Feb 6, 2018, at 5:05 PM, Greg Ward <gregoryjward at gmail.com> wrote:
> 
> Hi Raghu,
> 
> It looks like your HDR image header is missing the necessary view information.  Typically, this might be something like:
> 
> VIEW= -vta -vh 180 -vv 180
> 
> for a perspective such as yours.  You should be sure that your fisheye mapping corresponds to one of the standard Radiance types.
> 
> Best,
> -Greg
> 
> From: raghuram kalyanam <kalyanam at rhrk.uni-kl.de>
> Date: February 6, 2018 5:21:59 AM PST
> 
> Hi All,
> 
> I am trying to asses visual discomfort  using fisheye HDR images. We generated HDR image                     from a set of 360 degree LDRs and then converted to fisheye HDR ( using a custom made tools). The intension was to use these Fisheye HDRs as input to Evalglare and get DGP value. The Camera used is Ricoh Theta V 360 degree camera.
> 
> The problem I am facing is, the DGP calculated from the generated fisheye HDR with Evalglare is always 1.0. We did the calibration but I would like to have expert opinion from you people, what is going wrong with these set of images. Here is the link to the pictures.
> 
> It would be great if anyone could identify the issue.
> 
> Best Regards,
> Raghu
> 
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