Filters for Telyt 400 and 560

[Fritz Jah]

I recently purchased two Telyt-V lens, the 400mm/6.8 and the 560mm/6.8, and could anyone please help me with some details regarding using filters? According to my "Delaney" book, both use a Leica Series 7 size filter in the slot machined into the lens tube behind the aperature diaphram. My questions are, first, is there a holder/adapter involved in securing the filter before placing it into the tube's slot; and, second, what is the physical size of a Series 7 filter if I have to source the item through Tiffen, B&W, or some other manufacturer? Also, would anyone be able to tell me what the physical size of a Leica Series 8.5 filter is?


Thank you.

 

[Ben Z]

I've got the 400/6.8. Series 7 filters are readily available new and used and simply drop into the slot. Some thin-mount 49mm filters also fit, and I've ground off the male threads on standard 49mm filters and then they fit too.

Also, the threads at the front of the 400mm lens (for the nameplate ring holding the glass in place) are the same as for a standard 72mm filter. Unfortunately they begin too far in, so the rim of a 72mm filter hits the rim before the threads can engage. However, fortunately I found that a 72-67 step-down adapter ring does attach securely, and 67mm filters do not vignette. That's how I use a polarizer on this lens, and the rest of the time I keep a UV filter on it. (This applies only to the 400. The 560 is much larger in front).