Actually, it looks like Hugin is not compensating for ISO Speed. The values that it's using are more like: ( 2*log($aperture) - log($et) ) / log(2)
I'm not sure if that's a bug in Hugin or intentional. And I can't find any documentation that shows that EXIFTOOL calculates EV at all. Does/can it? It also appears that Hugin is converting shutter speed values such as "1.3" to more precise values such as "1 + 1/3" (unless there's some way to get EXIFTOOL to output more precise values that I've never figured out). Do you have any insight here? But where I'm really confused is that I have a project with different JPEG files -- all with the same exposure settings (each is the third shot of a bracketed set and the EXIF info shows each to have: ISO=400, Aperture=18.0, Shutter Speed=1.3). But, for some reason, Hugin calculates different EV's for each: Image 1: Eev7.96133843254863 Image 2: Eev8.22471080582863 Image 3: Eev8.01714501898585 Image 4: Eev7.92977368023845 Image 5: Eev7.92771999334261 Image 6: Eev7.91554178809828 Image 7: Eev7.9863593751747 Image 8: Eev7.94803346282545 Image 9: Eev7.87540508845236 Even more strange, Hugin calculates the EV's consistently for the 1st and 2nd shots in the bracketed sets (all the 1st shots get exactly the same Eev as do all the 2nd shots). It's just this 3rd set of image that have this weird variation. Is there some other weird factor that Hugin is using to calculate EV that I'm not accounting for? Or is there a high-precision mode to use to get data via EXIFTOOL? -Chris On Feb 1, 2:11 am, "bruno.postle" <[email protected]> wrote: > On Feb 1, 6:28 am, Chris Parrish <[email protected]> > wrote: > > > I am building a script that batch creates PTO and PTO.MK files for > > sets of pano images. I do this based on templates of these files (I > > use a pano head allowing me to reuse the same script settings in these > > templates). > > > The problem is that, while I can keep the lens and transform settings, > > I do need to change the Eev value to match the actual images' exposure > > values. I can get all the data using EXIFTOOL but when I calculate > > the EV I don't get what Hugin is getting. > > > Does anyone know Hugin's actual formula? > > EV (light value) is fairly standard, Hugin should be doing it the same > as exiftool (and does as far as I know). > > It's a log scale where a value of 0.0 is defined as f/1.0 at 1.0 > second with ISO 100), this is how it is calculated: > > (2*log ($aperture) - log($et) - log($iso/100)) / log(2) > > -- > Bruno -- You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/hugin-ptx
