wwp@yahoogroups.com:
Re: fc-e9 CA correction
wbr_venlo 2005-Sep-15 17:39:00
Thank you for the compliment,
Thanks to your and Eriks tutorial I started thinking about CA that
my own lens was showing me every image. So your tutorial isn't
obsolete at all. The more ways appear the better, because then we (at
least me !)enjoy, keep sharp and maybe find more better solutions.
Indeed the hardest part is finding shifts that lead to good results.
It is a good practise to watch carefully what happens during the
proces, i.e. if your R-squared is not so close to 1 or you are not
satisfied with the result, you could do a second loop with slightly
different values. Keep in mind that the largest contribution come
from the outer rays.
I choosed correction points in a vertical line to make life easy. I
have to care only for movements in one direction and can concentrate
on the result.
If I had to cerrect a full frame image I would turn the camera in
such a way that the diagonal line of the image was in a vertical
direction (from corner to corner). Of course the subject(object?)
that you capture should be in that line. Later on I turned it
vertical again and had only to deal with one direction of movement.
enjoy, Wil
--- In #removed#, Jim Watters <#removed#> wrote:
> Brilliant. Your results are perfect.
>
> The hardest part is still step 1, coming up with the various shift
> values at the different radius.
> I see that Eric has also updated PTShift.
http://www.pinlady.net/vr/#anchor2
> I will test this too.
> I see that my original tutorial is becoming completely obsolete. :-
)
>
> I was thinking you used vertical shift because it would be faster
but a
> quick test showed me it was the same speed as radial shift.
>
> Vertical shift will not work for full frame fisheye to make sure
the
> image is corrected in the corners.
>
> Great work. I see I have much to learn about Excel and graphing.
I
> will take some images through your steps and let you know what
happens.
>
>
> --
>
> Jim Watters
>
> Graphic Software Developer
> http://photocreations.ca