[Rtk-users] Object isocenter shift

[Cyril Mory]

Well, if it's just that, you should not worry about it : you cannot 
perfectly center your object, even if you try. And most objects (e.g. 
patients) do not even have a "center". So it does not make sense to 
struggle to have the center of the object perfectly match the isocenter 
of the acquisition device.

You can either live with that (it is perfectly fine for most 
applications), or try one of these things:
- If you can re-do the acquisition, you should try to have your object's 
center _roughly_ match the system's isocenter, because that's where you 
will have the least artifacts
- Reconstruct your object as it is (it will work fine, unless there are 
other problems), but select the origin and size of your reconstructed 
volume carefully to have your object's center roughly at the center of 
your reconstructed volume.

If you are not familiar with the exact definition of "origin", "spacing" 
and "size" of an itk::image, read section 4.1.4 of the ITK software 
guide (https://itk.org/ItkSoftwareGuide.pdf). This is both clear, short, 
and something extremely important to understand.

I hope it helps,
Cyril



On 05/17/2016 01:07 PM, AMJAD N wrote:
> Hello,
>
> As my previous thread caused some confusion, I am attaching an image 
> showing the same in detail.
>
> As you can see my object center is not aligned with isocenter line. 
> Besides it is offset by DX and DY values. In my case you can see the 
> object center as red dot.
>
> Is there any method in RTK to nullify this offset effect?
> Will the rotation of turntable affect the reconstruction due to this 
> offset?
>
>
> _______________________________________________
> Rtk-users mailing list
> Rtk-users at public.kitware.com
> http://public.kitware.com/mailman/listinfo/rtk-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/rtk-users/attachments/20160517/ac2c12f7/attachment-0010.html>