[Paleo Pete]

Just decided to bite the bullet and tear into a SMC Pentax 50mm f1.4 with minor fungus and see if I could finish cleaning it up. This seems to be a very good lens, I snapped a few shots with it on the K 30 a few days ago, and it did a very good job, but I knew it still had some remnants of fungus in it that I was unable to get to last time I tried, couldn't get one of the front elements loose, keeper ring was to tight. Dug out my old machinists calipers and ussed it to undo the offending retainer ring, that did the trick, a bit of work with some acetone and it looks like the fungus is gone, did a better cleaning job and I don't think any dust is left inside, or very little anyway, that will take a few days to really be sure. Last time after it got shook around in the back seat it started to show a little dust. It had some light fungus on the back side of the inner front element, and a small spot on another behind that. All of it on the outside edges, didn't seem to affect pictures at all. Now it looks like it's all gone, I'm pleased...

All I've done so far is a shot or two of a model car I built, will have it out in the field in the next couple of days for some macro shots, the last ones I took looked good.

OK thing is, and this is the reason for posting this, all my other 50mm Pentax lenses have 49mm filter rings. This one has a 52mm filter ring. I didn't know it, nothing marked, tried to put on a 49mm UV filter to keep dust and smudges off, and it fell right off..HUH??? Started digging around and found another 52mm filter, it fits perfect.

So anyone have any info about this lens? I knew it was 52mm long ago, just never bothered to check into it. I saw fungus so I put it up and didn't think too much about it. I looked through the reviews here at PF, everyone thinks this is a great lens. But I know almost nothing about this lens, except that it gets damn fine pictures...and until an hour ago it had fungus in it...

Looking forward to using it anyway, ever since picking up again a few days ago I've been grabbing it as much as I do my A series 50mm, and for me to do that it has to be a good lens. The A 50 has been my favorite ever since I put it on the K-x and took a few macros...No other 50mm I have can match either one and I'm not sure which one I like better...

So anybody know any history on it? What range of cameras it came on? General age? Anything? This might be the one that came on my old KX, I'm not sure. I'll probably have a couple of shots to show off before long, have to go out in a few minutes, if it's clear I might see about some starry night shots...

I just wondered about it, I thought it was odd that one 50mm lens had a different filter size than the others, but never have tried to find out anything about it...

[jatrax]

This k-mount, yes? If so the lens database says 52mm filter for the K series 1.4 but it drops to 49mm for the M series and later.

[Swift1]

You have what people refer to as a K series lens. Would have come with a KX or K2, maybe as an option with a KM.
This was the only 50/1.4 Pentax ever made with a 52mm filter thread. It's basically a SMC Tak 50/1.4 with a K mount. It was replaced by the Pentax-M 50/1.4 so I think it was only made for a couple of years so they are one of the rarer Pentax 50/1.4s.
I have one that I bought last year specifically to use with my K2. Great lens.


Here's a sample thread for it.
https://www.pentaxforums.com/forums/lens-sample-photo-archive/164503-pentax-k...4-samples.html

[Paleo Pete]

K lens is what I figured, I have the M and A both in f1.4 so I knew it was neither. (also have M 1.7 and f2) Probably came on my old KX, but can't remember. Looked at the reviews, but little there about the history of it. I haven't used it much since my film days, normally when I want a 50 I grab the A series 1.4, and since discovering fungus in this one I took a couple of shots long ago with the K-x to check it out, put it up and never thought much about it any more.

Getting shots like this with it (before cleaning up the fungus)



And that's not the best one.

and this just an hour ago, f8 ISO 3200



This shot is a 1600x1200 crop resized to 1024 x 768. At 3200 ISO I can't find but the tiniest bit of noise...pretty impressive...

I might just start grabbing this bad boy up more often, or keep it set up with some macro tubes and start getting a lot more use out of it...also got a few christmas lights shots, but nothing to write home about. I'm still getting the hang of that, never have done much night shooting except for a few fireworks here and there.