Originally posted by Cartesian Doubt
He siphoned off his Solar radiation which is bullshit. Electro Magnetism does sweet F.A. to light. Ever put a magnet in from of torch to see what it does ?... I'm sorry to ruin the suspense, but it does NOTHING !
He might as well have been siphoning off his powers with a vacuum cleaner, or a Jenna Jameson special

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And he Iron thing won't fly either ... how do we know Superman has hemoglobin, or Iron in his blood? And how do we know he has a electro magnetic CNS. For all we know his neurons use a biological fibre optics equivalent. So the previous argument allplies.
Light is made up of perpendicular and oscilating electrical and magnetic fields so the rationale behind Magneto's power to manipulate light through electromagnetism is entirely valid. But more importantly, what real world magnets do to light is irrelevant because magneto and DP have manipulated photons on panel.
Also, whether or not DP siphoned sunlight off SM is open to interpretation as he might have compromised the functioning of the bio-electrical aura that collects solar energy and gives SM his powers. Anyways, what matters is that it worked.
It's safe to assume he has iron in his blood because he bleeds red. As for the CNS, it is the simplest explanation, and while kryptonian physiology is obviously different from humans it also has too much in commom to assume otherwise. As I understand it, under a red sun they are just like people.