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		<subject index="0" >Re(3): CALIBRATION</subject>

		<tonames index="0" >S194 06E real time observing</tonames>

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Hi - no, I don't think these are related to Newton's rings, it's just that the edges of the
field of view don't get as much light as the inner portion, so the illumination across the field is not uniform.

Andy

Jonathan Ransom 2 writes:
Thx for the pic. I'm not too familier with reflecters, would the ring like structures be anything like Newton rings that you would see when setting up?