I'm trying to use hdrgen with a response curve created by photosphere. For the image, I have calibration points measured with a luminance meter, and when I make the hdr with photosphere, I get an accurate luminance measurement, but hdrgen gives me a value that's consistently ~10% higher. This is surprising as (I think) I'm using the same response curve for each process.
And here's the response curve from Photosphere:
"Canon"|"Canon EOS 5D Mark II"|"v.0"|{7.135383e-03,-3.556814e-02,2.441168e+00,-5.786777e+00,4.462320e+00}|{4.543790e-03,3.363440e-02,1.917460e+00,-4.660105e+00,3.792747e+00}|{3.956902e-03,3.244581e-02,1.827308e+00,-4.505138e+00,3.729707e+00}
Am I missing any hdrgen options, or perhaps making an error in my .rsp file? Thanks in advance for any insights.
Hi Michael,
> I'm trying to use hdrgen with a response curve created by photosphere.
For the image, I have calibration points measured with a luminance
meter, and when I make the hdr with photosphere, I get an accurate
luminance measurement, but hdrgen gives me a value that's consistently
~10% higher. This is surprising as (I think) I'm using the same response
curve for each process.
Here's what I put into canon_5D.rsp:
7.135383e-03 -3.556814e-02 2.441168e+00 -5.786777e+00 4.462320e+00
4.543790e-03 3.363440e-02 1.917460e+00 -4.660105e+00 3.792747e+00
3.956902e-03 3.244581e-02 1.827308e+00 -4.505138e+00 3.729707e+00
The first number in each line in an RSP file is the order of the polynome. Since it is missing in the RSP above (the one you hand-crafted from the Photosphere response), hdrgen deems it invalid and overwrites it with a new one. Try pre-pending a '6 ' to all three lines. hdrgen should than be happy and use the RSP that you supplied, rather than generate one from scratch.
And here's the response curve from Photosphere:
"Canon"|"Canon EOS 5D Mark
II"|"v.0"|{7.135383e-03,-3.556814e-02,2.441168e+00,-5.786777e+00,4.462320e+00}|{4.543790e-03,3.363440e-02,1.917460e+00,-4.660105e+00,3.792747e+00}|{3.956902e-03,3.244581e-02,1.827308e+00,-4.505138e+00,3.729707e+00}
Am I missing any hdrgen options, or perhaps making an error in my .rsp
file? Thanks in advance for any insights.
It seems like hdrgen really wants a 3rd order polynomial (no matter what I put into the .rsp, hdrgen overwrites it as such), and I'm not too sure how to translate the 5 values for the R, G, and B channels generated by Photosphere.
As another data point, the other camera curves in my Photosphere preferences file have a variety of values, either 4, 5 or 6 for each channel, depending on the camera.
As a work around, I can apply a multiplier to the .rsp that hdrgen makes, and that gets me pretty close. But I'd also love to know if there's a more direct way to translate the Photosphere data into hdrgen friendly data.
Thanks all -
Mike
···
On May 13, 2013, at 12:14 PM, Axel Jacobs wrote:
Hi Michael,
> I'm trying to use hdrgen with a response curve created by photosphere.
For the image, I have calibration points measured with a luminance
meter, and when I make the hdr with photosphere, I get an accurate
luminance measurement, but hdrgen gives me a value that's consistently
~10% higher. This is surprising as (I think) I'm using the same response
curve for each process.
Here's what I put into canon_5D.rsp:
7.135383e-03 -3.556814e-02 2.441168e+00 -5.786777e+00 4.462320e+00
4.543790e-03 3.363440e-02 1.917460e+00 -4.660105e+00 3.792747e+00
3.956902e-03 3.244581e-02 1.827308e+00 -4.505138e+00 3.729707e+00
The first number in each line in an RSP file is the order of the polynome. Since it is missing in the RSP above (the one you hand-crafted from the Photosphere response), hdrgen deems it invalid and overwrites it with a new one. Try pre-pending a '6 ' to all three lines. hdrgen should than be happy and use the RSP that you supplied, rather than generate one from scratch.
And here's the response curve from Photosphere:
"Canon"|"Canon EOS 5D Mark
II"|"v.0"|{7.135383e-03,-3.556814e-02,2.441168e+00,-5.786777e+00,4.462320e+00}|{4.543790e-03,3.363440e-02,1.917460e+00,-4.660105e+00,3.792747e+00}|{3.956902e-03,3.244581e-02,1.827308e+00,-4.505138e+00,3.729707e+00}
Am I missing any hdrgen options, or perhaps making an error in my .rsp
file? Thanks in advance for any insights.
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: http://www.jaloxa.eu/webhdr/cameras/Canon__Canon_EOS_5D.shtml
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
···
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
I think hdrgen copes well with scientific notation, but just to double-check: try converting from scientific notation to straight decimal.
Also, I did notice with some of my won sequences that wood with its grain and large areas of non-grey can be tricky. Just for the calibration, I suggest you choose a grey background.
Axel
···
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
The rsp looks good - nice and smooth, which makes sense as Photosphere seems to have no trouble with these values. I also tried straight decimal format, and still no luck...
Very curious...
···
On May 13, 2013, at 1:31 PM, Axel Jacobs wrote:
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: WebHDR Camera Info
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
As I recall, the order is reverse between Photosphere and hdrgen. If the R response is from your Photosphere file is
7.135383e-03,-3.556814e-02,2.441168e+00,-5.786777e+00,4.462320e+00
it should be a "mirror image" in hdrgen:
4.462320e+00, -5.786777e+00, 2.441168e+00, -3.556814e-02, 7.135383e-03
Mehlika
···
On Mon, 13 May 2013, Michael Martinez wrote:
The rsp looks good - nice and smooth, which makes sense as Photosphere seems to have no trouble with these values. I also tried straight decimal format, and still no luck...
Very curious...
On May 13, 2013, at 1:31 PM, Axel Jacobs wrote:
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: WebHDR Camera Info
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
Ah ha!! That's the trick... Things look great now.
Many thanks, both to Axel and Mehlika.
MM
···
On May 13, 2013, at 3:36 PM, Mehlika Inanici wrote:
As I recall, the order is reverse between Photosphere and hdrgen. If the R response is from your Photosphere file is
7.135383e-03,-3.556814e-02,2.441168e+00,-5.786777e+00,4.462320e+00
it should be a "mirror image" in hdrgen:
4.462320e+00, -5.786777e+00, 2.441168e+00, -3.556814e-02, 7.135383e-03
Mehlika
On Mon, 13 May 2013, Michael Martinez wrote:
The rsp looks good - nice and smooth, which makes sense as Photosphere seems to have no trouble with these values. I also tried straight decimal format, and still no luck...
Very curious...
On May 13, 2013, at 1:31 PM, Axel Jacobs wrote:
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: WebHDR Camera Info
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
I am not entirely sure that I remember this correctly, but I once looked at these
camera curves in photosphere for the purpose of plotting them. I seem to recall
that the coefficients are reversed relative to how you might expect them.
It may be worth trying to reverse the order of the coefficients, so for the first of
the three lines this would be:
On May 13, 2013, at 10:31 PM, Axel Jacobs <[email protected]> wrote:
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: WebHDR Camera Info
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
Erik's post came in after Mehlika's because he got caught in the moderator trap -- his e-mail was not "on the list."
My apologies for not answering the original post, but I was on a plane or two....
Cheers,
-Greg
···
From: Erik Reinhard <[email protected]>
Date: May 13, 2013 2:24:48 PM PDT
Hi All,
I am not entirely sure that I remember this correctly, but I once looked at these
camera curves in photosphere for the purpose of plotting them. I seem to recall
that the coefficients are reversed relative to how you might expect them.
It may be worth trying to reverse the order of the coefficients, so for the first of
the three lines this would be:
On May 13, 2013, at 10:31 PM, Axel Jacobs <[email protected]> wrote:
Right, so we are on the right track--hdrgen no longer rejects the RSP.
Next question is: how good is the RSP? Try plotting it. If it is smooth and monotonic, without any kinks in it, it's a good one. Otherwise, try generating it from a different sequence. The 5D is used a lot on WebHDR: WebHDR Camera Info
How does your RSP compare with the averaged one? Note that there is no quality control, and even 'wonky' ones make it into the average.
Axel
On 05/13/2013 09:21 PM, Michael Martinez wrote:
Using a 4 in front of the Photosphere numbers like this:
I was wondering if there are any newer versions of HDRgen or Photosphere or if anyone can recommend any substitutes. I have the 64-bit version of Photosphere on macOS 15.1, which was the only version that I could install. But as soon as I want to add any images, or even open the folders that contain the images, it crashes. I have access to a Windows computer but I personally don’t have the authority to install my software and I was informed by our IT department that hdrgen cannot be installed on Windows 11 because it only supports Visual C++ 2010. I would appreciate your insights.
Unfortunately, we have not found the time or resources to fix the problems with Photosphere on newer versions of macOS. You can use hdrgen, and I just uploaded an update to hdrgen and hdrcvt compiled for Apple Silicon here.
If you are desparate to get Photosphere working, the cheapest route may be to pick up an older Intel Mac for cheap that can run macOS 10.13 (see Wikipedia chart of Supported macOS releases here) and install it on that. MacSales has the optimal mid-2015 Macbook Pro with a decent configuration for around $400 here. (Not meant as a plug, just an example.)
