<p>Jacques,<br>
Thank you for your response and especially for posting the link to your beautiful night photo of Hong Kong, which is sharp and clear across the frame. I would enjoy seeing other images you've made with this lens, especially any in bright sunlight. You mention that the Mamiya repair center told you the lens has a floating element which, if I understand correctly, might make it the "ULD" version. Is that the case? Currently the 50mm ULD fetches two to three times the price of the non-ULD versions on the used market. I'm wondering if the premium for the ULD floating element is worth it. <br>
The use of UV filters has always been controversial among photographers. They do block UV light, as does window glass. Some people use them on all their lenses; I don't own any. If I'm going to photograph someone at the beach along our foggy and windy far-northern California coast and want to protect my lenses from salt spray, I prefer to use a warming filter. When it comes to whether or not to use UV filters at all, I politely refuse to argue the point.<br>
This discussion has been useful to me, because I've had my eye on a couple of lenses for my RZ that are steeply discounted due to internal fungus or mild hazing, and I want to learn all I can about how these defects impact image quality, if at all. Any additional examples you can offer taken with your lens would be greatly appreciated.<br>
With kind regards,<br>
Mark H.</p>