[ptx] HFOV, focal distance...

[manouchk]

Le Jeudi 2 Juin 2005 12:26, Brian Innes a écrit :
> Didier Hérisson wrote:
> >Le Mercredi 1 Juin 2005 21:23, manouchk a écrit :
> >>Le Lundi 30 Mai 2005 08:55, Emmanuel a écrit :
> >>>Hi,
> >>>
> >>>I'd like to know if providing a good value of the HFOV is sufficient to
> >>>do a good stitching in hugin or if it is needed to adjust well the focal
> >>>length and cropping ?
> >>
> >>As noone seems to know the answer of my previous question, I ask my
> >>question in another way, what is the cropping factor?
> >
> >Isn't it the ratio between the CCD and a 35mm detector? In the case of
> > reflex (SLR?) cameras, people think about focales length instead of HFOV,
> > with the 35mm standard size in mind. My guess is, HFOV is calculated from
> > focal length by Hugin, assuming a standard 24*36mm detector.
> >If you know the '35mm equivalent' of your focal length, just put it as
> > focal length and a cropping factor of 1.

First thank you to all who answered! and specially for  Terje that provided me 
optimized values of the optical parameters, I will tried it on my camera and 
see if I can stitch with zero residual control point errors after
optimization!

> Doesn't the '35 mm' equivelant focal length appear in the exif tags of
> the images taken with Olympus cameras?

I think not because hugin should load it normally?


> For my Olympus C5000, it has a sensor size of 7.18 x 5.32 mm, which
> gives a diagonal of 8.94mm, giving a crop factor of 4.84 (43.3 / sensor
> diagonal size)

OK, so I will may be just modify the HFOV as the cropping as not a real 
signification... in my case...