[AstroPy] Running wcs_pix2world for all image pixels

[Maik Riechert]

Hi,

I'm quite new to python and astropy and got stuck at the following which 
probably is extremely easy to do.

I created a WCS object out of a FITS header and wanted to get the RA/Dec 
coordinates of each image pixel. I tried:

w.wcs_pix2world(np.ndindex(4256, 2832), 0)

where 4256x2832 are the image dimensions. This returns 'ValueError: 
object of too small depth for desired array'. I was trying to avoid 
allocating an array with all pixel coordinates and thought an iterator 
would work too.

What would you recommend for my case (translating every pixel)?

Cheers and thanks,
Maik