[Elphel-support] (no subject)

[201图像所]

Hi,

Many thanks for your reply.
Make test images and use them to estimate these values? Could you
please explain this in more details ? What are test images? And how to
use these values to estimate?

Best regards
Song Rui

2014-05-08 2:13 GMT+08:00 Oleg <support-list at support.elphel.com>:
> Hi,
>
>> But,i fall in the trouble of vignetting recently.I find you use the
>> method of Function approximation.I look up some papers,the Function is
>> f(i,j) = cosh(rx*(x-x0))*cosh(ry*(y-y0)) +c .However,yours is
>> f(x,y)=p*(x-x0)^2 +q*(y-y0)^2 + c    ----->>    f(x,y)=AX*x^2 + BX*x +
>> AY*y^2 + BY*y + c.
>> Could i ask you how to get the Function ,and how to set the initial
>> value of AX、AY、BX、BY and C?
>
>
> I haven't dealt with this.
> Make test images and use them to estimate these values - look at the
> vignetting gradient function and pick several points and solve the system.
>
> Best regards,
> Oleg Dzhimiev
> Electronics Engineer
> phone: +1 801 783 5555 x124
> Elphel, Inc.