[onlineflyer]

Hi all, I'm looking at a Pentax lens on fleebay. The condition is described as follows: "lens is in overall excellent condition and image quality is impressive. The optics are without any scratches or noticeable cleaning marks. However on the element just below the front group there looks to be a smallish patch of dried condensation around a small section of its edge… this is one of those issues that is invisible unless you turn the lens in a way that it catches the light and then it can be seen. It is without fungus or hazing and is otherwise very clean internally with minimal dust present. It is focusing smoothly and the aperture is snappy with the blades in excellent condition."

I requested pictures from the seller. What questions should I ask, what should I concerned with?

Thx in advance

[Just1MoreDave]

The edge is really unlikely to be in any shot. I think you just have to worry about progression - is that "small section" going to get bigger. Then how difficult it is to fix. Then if it's the only copy ever made or you could keep looking. Also if you can't fix it, you will have a tougher time reselling it.

I have an SMC Pentax-A 135/2.8 that I bought with some fungus on the edge of the front element (described by seller). What I thought at the time was it was an easy fix and it wouldn't affect photos. I was right about photos but couldn't immediately figure out how to take apart the lens. I blasted the lens with UV and left it. I live in a pretty hostile environment for fungus - we add humidity to the house air to get it up to 15%. It hasn't gotten worse or spread.

That's a four-element prime and at it's peak, a $120 lens in perfect shape. Worth the risk for me even if it went badly and I replaced it.

[Fenwoodian]

However on the element just below the front group there looks to be a smallish patch of dried condensation around a small section of its edge."

I requested pictures from the seller. What questions should I ask, what should I concerned with?

Thx in advance

Unless you are proficient at taking a lens apart and doing a CLA job on it, don't buy this lens.

If the defect (dried condensation) were behind either the front or the rear elements, it would be a relatively easy "do it yourself" fix. However, the seller said that this defect is below the "front group". That means it's deeper inside of the lens, which means it's probably difficult for the average photographer to get to the defect to correct.

But, if the lens is cheap enough, and you can live with the defect and are willing to gamble that it doesn't get worse you might want to buy the lens, live with the defect and hope it does not either affect your photos or get worse.

[stevebrot]

lens is in overall excellent condition

If there is a visible mark on an internal element, the description is not accurate. Dried condensation, typically should not leave much of a mark (distilled water). I would ask for photos of the mark. I wonder too what is meant by "noticeable" when referring to cleaning marks.

If you really want that model lens and if it is hard to come by and if the price is really good, then it may be worth pursuing. If the value proposition is not there (missing one or more of the three considerations), there is no need to seriously consider this seller.

Unless you are proficient at taking a lens apart and doing a CLA job on it, don't buy this lens.

This too ^ ^ ^


Steve

[onlineflyer]

Here's a pic the seller provided.

[boriscleto]

Run, don't walk, away from that lens...

[edom31]

Here's a pic the seller provided.

That is likely within a cemented group - no fix or cleaning (try to get a shcematic/lens formula for that lens and see whether or not there are cemented groups - if it is a zoom lens, forget it, not worth at-home disassemble). Also, there are some 'freckles' that are noticeable at other areas...

[onlineflyer]

Thanks for the input, everyone. Guess I'll pass on this one.

PF members are the best.

[MetalUndivided]

Run, don't walk, away from that lens...

Why is that? Can you elaborate? I'm really curious, it doesn't seem to be too bad.

[Astro-Baby]

Could be the start of delamination of a cemented pair which woukd be baaad but it could also be something simple like someone has put to much lens cleaner on and its gotten behind the glass. Depends how tough the front element is to get out pn this lens. I only mess about with easy to fix stuff like Pentax M series and early Rokkors where everything is pretty simple to remove.

[edom31]

I only mess about with easy to fix stuff like Pentax M series and early Rokkors where everything is pretty simple to remove.

Same here... I once got OCD about a speck of dust in the inner elements of my first Tamron 103A - long story short, the iris blades are extremely difficult to align and keep together once they fall apart... Now, I have a second 103A and a disassembled one for spare parts.