Originally posted by LMRacing I somehow doubt its dust on the sensor, since the lens has been siting for years without caps and the camera still doesn't have 2K shutter operations on it and is only three weeks old I'd blame the lens first. also there is nothing in any of my shots with my newer lenses.
For what I would use the lens for I dont mind sending it off and paying somebody a few dollars to clean it, especialy at the price I got it for. I had been looking at the Rinicon (or however you spell it) lens on Overstock for $100 for the 500mm and I belive this to be a much better quality lens that I got for half the price. even if I spend $100 to have it cleaned properly I still spent money on better glass than the other would have been.
I doubt it will be used for too much else than the occasional shot at the moon, possibly a photo at some wildlife or a blue sky on occasion. It will probobly trek with me for some scenic shots at my yearly trip to deals gap
My first impression would be that the lens does have fungus on it. In and of itself if it is not too bad it may well not be a major factor in capturing images. This lenses rear element is recessed quite far into the lens and it is very difficult to reach. I have cleaned these for others in the past, the last being two years ago.
My suggestion is that you go to a pharmacy and get very long wooden cotton swabs. Wrap the cotton swabs in lint free LENS tissue and moisten LIGHTLY witih a lens cleaner. Work in sections and be very patient. It will take many passes to get this clean. It will get worse before it gets better
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If you use canned air at all during the process... DO NOT SHAKE THE CAN AT ALL. It will really set you back.
Good luck.
Stephen