The right way to access red channel in Lena

[Adam Hughes]

I don't think the image came through.  Let me attach it

On Thursday, March 26, 2015 at 7:16:12 PM UTC-4, Adam Hughes wrote:
>
> I'm trying to build a filter to show only the red channel in the lena 
> image.  I defined two masks:
>
> (1,0,0)
> (255,0,0)
>
> Oddly, the (255,0,0) gives me the correct plot when doing imshow(), but 
> (1,0,0) doesn't.  Why does the (1,0,0) mask lead to light regions being 
> dark and dark regions being light?  Here's a working example:
>
> %pylab inline
> from skimage.data import lena
>
> lena = lena()
>
> f, (ax1, ax2) = plt.subplots(1,2, figsize=(8,6))
>
> ax1.imshow(lena*(1,0,0))
> ax2.imshow(lena*(255,0,0))
>
>
>
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