Hi Vincent,
> In the FSL /data/standard folder there are several templates with different resolutions (i.e. 2x2x2mm; 1x1x1mm; 0.5x0.5x0.5mm).
>
> I noticed that some software packages use low resolution (2x2x2mm) templates as reference image for warping, even if a high resolution (1x1x1mm) template is available.
> Warping a high-resolution scan to a low-resolution template the warped image inherits the resolution of the template. Hereby, I lose information, right?
No, the template used for estimating the warps and the final resolution of the warped image are independent. You can run fnirt to the 2mm template to estimate the parameters and then resample to the 1mm template.
> - When warping an image with 1x1x1mm voxels to standard space, are there any disadvantages of warping to the 1x1x1 template instead of the 2x2x2 template (other than file size being larger)?
It takes a lot longer.
> - Does warping to 1x1x1mm always yield a better warp?
Only if your warp resolution is such that it warrants it. In FSL we usually use a warp resolution of 10mm, and in that case there is no advantage with the 1mm template.
> - What about warping a 2x2x2 image to a 1x1x1 template? Should I rather use the 2x2x2 template in this case?
Warping a 2mm image to a 1mm template would make very little sense.
Good luck Jesper
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