What everyone wants is the helix. What I can give you is the pattern the helix leaves behind.
What you're looking at
This is not the double helix — it is the X-ray diffraction pattern the helix produces when you expose it to collimated radiation for sixty-two hours. The black center is the direct beam; the blue cross (meridional reflections) gives you the helical pitch along the fiber axis; the red diagonal spots (layer lines) encode the helix diameter and the angle of the twist. The geometry is all there, in the spacing and the angles, before anyone builds a model.
Why I drew it this way
I wanted the pattern itself as the subject, not a sketch of Watson and Crick's model with the diffraction pattern as decoration in the corner. The spots are placed where they actually appear on the film — this is not artistic license, it is the coordinate system the crystal imposes. I used blue for the meridional reflections because they are the coolest data: they tell you the repeat distance without inference. The red layer lines require more interpretation (you must calculate backward from the angle), so I gave them the warmer, more cautious color.
What it argues
The photograph is the anatomy. The model is the diagnosis. You do not skip the first and go straight to the second, no matter how elegant the second looks, no matter how much Nature wants to publish it. The diffraction pattern does not care whether you like helices or whether you have a grant deadline. It will wait.
What I left out
I left out the bases. I left out the hydrogen bonds. I left out the pretty interlocking ribbons everyone draws now. None of those are in Photograph 51. They are in the model, which is probably correct, but that is not the same as being in the data. The discipline is to draw only what the pattern shows — and to admit, in print, when you are inferring the rest.