[lats]

Hey all,

I'm off this evening to check out a bunch of old K and KA mount lenses which I'm hoping to purchase some of depending on condition.

I've never purchased second hand so was hoping someone might be able to give me some advise on what I need to look out for other than blemishes on the glass etc.

Thanks very much.

Cheers
Andrew

[pschlute]

Make sure the aperture will stop down fully and snap back quickly when released. Some old lenses end up with a tiny bit of grease on the blades leading to stick aperture syndrome.

[Quicksand]

Don't worry about dust inside (reasonable amounts, at least). It's pretty much inevitable, and it won't harm your photos.

But DO look for haze, fungus, and degrading lens cement. With the aperture held wide open, look through the lens in both directions, checking particularly around the edges for fogginess, off-color bits, or funky-looking patterns on the internal glass surfaces.

Personally, I hold it up to a light, and when possible against a well-lit white background (like a sheet of paper). Others might have better suggestions and better descriptions of what to look for, since my experiences with fungus have been (thankfully!) quite limited.

[breischl]

There's a nice article written on this over in the articles section.

https://www.pentaxforums.com/forums/pentax-lens-articles/59245-pawnshop-lense...ers-guide.html

[apisto]

This article might be useful.
https://www.pentaxforums.com/forums/pentax-lens-articles/59245-pawnshop-lense...ers-guide.html

[Peter Zack]

It might be too late but if you have any type of list, maybe post it and we can give you a rough guide on values.

A hand held magnifying glass can be your friend. Looking for the things that others have already discribed. But the main thingsa are:
1) Really excessive dust. Some dust is normal.
2) any multi coating issues. Small blemishes on the front element probably will not cause image issues but on the rear, they can easily show up in pictures. Also MC or SMA coatings can peel off over use and time if scratched. So clean the outer lens surfaces to check closely.
3) look for delaminations which usually show up as discolourations around the glass edges on the outside or bubbles on the inside. Use good light and the magnifying glass.
4) test the aperture blades that they snap in place fast and accurately. Look for oil on the blades. Both sides should be clean on both sides when closed down. Many lenses are easy to clean though and don't pass on a lens for this. You might make a great deal on a lens because of this and then clean it yourself or have Eric clean it professionally. ($40 per lens)
5) Haze fog or fungus. A lot is bad news but a small amount on a good lens is a chance to get a lens cheap and send to Eric for cleaning. But if it's bad, pass. The inside metal barrelll and bits will be infected as well and nearly impossible to remove. Plus the glass will be etched from the fungus if it's bad or been there a long time.
6) smooth lens functions. Focus ring etc. No grinding or any noticable issues. Aperture ring clicks firmly into place at stops but easy to move up or down.

Test any KA lens on a camera to make sure the exposures are accurate. That the contacts work as they should.

That's about it.

[lats]

Hi Guys,

Thanks for all the info.
Extremely helpful.

I'd love to post a list, but I'm not actually sure what he has. I rang him because he had an old 40mm/2.8 pancake. I'm interested in getting this to see if id' like to spend the money on the more modern version. (well, it's that or the 43Ltd)

Through discussing with him he stated he had collected pentax lenses for a number of years and asked what else I was looking for. He mentioned he had a number of 50mm primes (he mentioned a 1.2 and a 1.4) a 135 telephoto and some others I cannot remember.

I have a feeling all will be K mount and not KA's as he has two MX bodies to sell as well.

What should I expect on prices for the 4 lenses I mentioned above. He is trying to bundle an MX body with the 40 for $175....

Thanks again.

Andrew

[Peter Zack]

Well the M SMC 40mm is debatable. Some have it and quite like it, others have mixed feelings on the lens. It's worth checking the lens review database here on the forums for any users comments. IMO I wouldn't spend more than $100 but hopefully closer to $80 CAD On Ebay it's probably worth around $150.

Lens database

The 50mm's If K mount as you think (this is assuming SMC of course):
K50mm f1.4 $100-125.00
K50mm f1.2 $275-325.00
135mm is nearly impossible to asses without knowing which one and there are plenty. But they can go from $25-150 depending on the version. If it is an f1.8 then just pass him your wallet and credit cards.

All of this is what I'd max out at and all would depend on near mint optics and very good cosmetics.

[lats]

Thanks Peter.
I feel much better equiped now. I've seen the Lens database. Very handy.
It's been a long time since my K1000 days and I'm loving getting back into the photographic world!
I'll look at the 40mm and if it is in good condition I may purchase, otherwise I'll save my money.

I'm hoping the 1.2 is a KA!!