rkc

I had a lens - I suspect it had been dunked in water at some point - with limescale on an inner surface making it look hazy. Cleaned off surprisingly well with vinegar. Might be worth a try if ...

Brilliant, thanks! I suppose after all this I'd better see about getting it mounted somehow and see what the images are like!

Their FAQs at https://navitar.com/contact/FAQs/faqs/ say Q: Who makes Navitar lenses? Where? We design and assemble most Navitar lenses at the Navitar manufacturing facility located at 200 Commerce ...

For what it's worth, my current guess is that it's a genuine Navitar product - they have a line called Raptar, which is described as follows (see http://wjmvs.com/products/lens/navitar/ ) Navitar’s ...

Hmm, Just found this page (not sure why my previous searches didn't find it) https://navitar.com/products/imaging-optics/large-format-lenses/raptar-pro/ There's a lens pictured on that page that ...

I'm not sure what the likely production date of this lens is - as far as I can tell the history of Seagull producing Minolta-inspired lenses in China dates back to the mid 1960s and into the 1990s. ...

Yes, definitely looking like a Seagull lens, but with an "almost Nikon" mount.

Fascinating and great research! My lens certainly does look a lot like the Seagull 24mm/2.8 pictured in that article you link - albeit with a different nameplate. The mount is definitely not MD ...

Hmmm, I took off the back plate to see if there were any signs of it having been "mount-switched" at some point but it all looks pretty original to me. I could probably get it to mount on Nikon ...

It won't fit on a Minolta AF 5000 body so I don't think so. Comparing it against a Nikkor 28mm from the same source, the mount bayonet looks visually identical, right down to the sizes of the ...

Thanks. Some more pictures (I never realized how hard it is to get a photo of a lens that shows detail of the bayonet!) The serial number format - SB-00333 6 - is a little unusual, perhaps that is ...

Found in among a box of mostly Minolta-mount lenses, but this does not seem to be, and my googling is not coming up with anything similar

Derwent Dam, Ladybower Stitched panorama from 8 shots with a CZJ Pancolar 50/1.8 (M42, Zebra version) on Canon R5

I have a CZJ Pancolar f/1.8 (zebra version) that focuses to 35cm or just under. I will check some of my other 50mm lenses when I get home.

As luck would have it, I just got another chipped adaptor - M42 this time, which means I was able to test it with a F/1.4 lens. I still see the exact same behaviour as with the prior adapter / ...

Yes, it seems to be focusing to infinity correctly. I just double checked and it looks like I had misremembered slightly - the chipped adaptor I have that is behaving oddly is a C/Y adaptor not a ...

FWIW I noticed exactly the same phenomenon with a chipped PK adaptor on my R5 (on a Canon EOS->RF adaptor).

I was agreeing with you... but in my experience the 100-500 is more unwieldy because it doesn't always stay retracted when carrying it. My point was you can leave the extension tube on permanently ...

I have both. Lots of discussion above about the advantages of the 100-500 with 1.4x option, most of which I agree with, but just a couple of things I would add: 1. The inability to retract with ...

I've just discovered another downside of the lens - because there's no electronics there's no lens info in the exif, meaning I can't just search Lightroom metadata to find the shots I took with it! ...