With a 100mm lens on 35mm camera how do I take a moon picture not too overexposed?

I try to take a picture of the moon with a 35mm camera and with 1000 mm lens but they keep coming out as a big bright circle on a black background. How can I get details of the moon? Even through a telescope too bright. I usually use 400 or 800 speed film as I have no clock motor and rely on faster exposure.
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