Raw2hdr for raspberry images

Hi everyone

I am trying to make HDR images from pictures taken with the raspberry pi camera module . As I would like to work with the raw data, I converted the JPEG+RAW (raspberry format) to DNG and then used raw2hdr to generate de hdr image, however I am getting the following error:

*image.tif:needs exposure calibration *
Failure generating HDR image

Does anyone know why is this appearing, or if there is another way to work with this image format?

The images I am using can be found in the next link: https://drive.google.com/drive/folders/10g4plWazgKmRjnc2PPdoyqzv51Fi_iil?usp=sharing

Thank you and best wishes.


Somehow, your DNG files have ISO set to 0, which is an illegal value. I don’t exactly know how to correct this.

Hi Greg, thanks for the response :slight_smile:
Could you tell me how can I check the ISO value of the DNG image?, When I check it with Exiftool value appears to be 100.

Yes – I’m not sure what’s happening to the ISO and the F-number in dcraw. There must be some kind of bug/shortcoming when reading DNG images. The fix is to add the following to the setting of the “@exiftags” array in the raw2hdr Perl script:

-ISO -ApertureValue>FNumber

You can edit the script in a text editor. I tried it and it seems to work for your image.

Thanks a lot Greg!

It now works without problems! Thank you!