Manual focus camera lenses

[SavingWithBabies]

Photography is a hobby of mine. It can be expensive however one interesting aspect is that many people enjoy using older manual focus lenses with modern cameras. This morning I disassembled one such lens to clean the aperture blades following this procedure:

http://www.kolumbus.fi/uusilehto/img/le ... ss/disass/

I ran into a snag getting the front of the body off so I only cleaned the blades from the rear however that was enough to restore functionality (and it was easy to do so if the mechanism binds up again with oil, I can simply clean it the same way again).

My purpose in posting is that this is a both a DIY skill and for those of us who like to hunt for treasure, it may be worth learning more about lenses. Both the value so you can know if it is worth buying to flip (or use and then pass on again at minimal to negative cost) and simple repair steps. In the above sequence, the lens comes apart easily and the two sets of elements are removed whole as components. So there is little concern about having to deal with aligning the optical system later. Performing a cleaning like this is surprisingly easy yet many people are afraid to do it.

In terms of what to buy, it gets a little more complicated. Some lenses are very common as they came with cameras. For Pentax, that would be the 50mm f2.0 lens. I would purchase one of those for at most $6-8 for the A variant (newest manual focus variant, I would pay slightly more for older variants). Of course, eBay is the easiest way to get a rough idea of value. To do so, you only need to know a couple of things about the lens:

1) focal length almost always measured in mm
2) maximum aperture which is written in a number of ways
3) brand (be sure to remove any screw on filter elements on the front if present -- don't confuse the lens brand with the filter brand)
4) condition:

* does the focus mechanism move smoothly?
* when looking through the lens at a bright light or the sky, how much dust is present? is there any fungus growing inside?
* scratches on the front or rear element?
* if coated, any obvious flaws with the coating on front or rear element?
* scratches on the lens body?
* dents in the front rim of the lens?
* does the aperture mechanism work?
* if newer lens, does auto focus work and/or the circuit boards inside the lens (starts to get complicated)

My advice if you're interested is to learn specifically how to do 1, 2 and 3. The vast majority of lenses you find will be common near junk. Often these are off brand lenses like JC Penny. But #2 is really the biggest hint in terms of value. The maximum aperture of a lens is basically how much light the lens lets in (when not stopped down or when the aperture mechanism is fully relaxed so the blades are hidden and not in the light path). #2 really varies by #1. So I can say things like:

If you see a 50mm lens with a maximum aperture of f1.2 or less and it's $20 or less, buy it right away. If it is a known brand (Cannon, Nikon, Pentax, Contax, Leica) and it's $50 or less, again buy it right away. As you learn more about what lenses are generally out there, it's easy to get a feel for rough value.

As I mentioned earlier, #2 is tricky so here I'll put the text that is around the front element of some of my lenses to give you an idea of how to parse out 1-3:

Olympus M.Zuiko Digital 14-42mm 1:3,5-5,6 ø37

1) 14-42mm so this is a zoom lens in which means the focal length can vary
2) 3,5-5,6 so the lens varies from a maximum aperture of f3.5 (at 14mm in this case) to f5.6 (at 42mm although might be at another point)
3) Olympus
4) Good -- it is plastic and light so I know it's a modern lens. It doesn't have an aperture ring so I can't set the aperture manually. The lens body rotates but it is clearly for the focal range as it makes the lens grow longer and shorter. There is another ring that doesn't feel like it is hooked up to anything (this is the manual focus ring -- it is electronic unlike older lenses so indeed it is only hooked up to a sensor not a physical mechanism). On rear of the lens where it connects to the camera there are a number of metal contacts. So this is clearly a modern auto focus lens. It happens to be the kit lens that came with an Olympus E-PM2 camera and is worth maybe $45-70 used.

The ø37 indicates 37mm filters can be screwed onto the front of the lens. Also the fact that the maximum aperture varies is a sign that this is not a top of the line lens although it is a weak indicator (until combined with the maximum aperture which strongly hints this is a kit lens as in a lens that came with a camera body and thus common).

Carl Zeiss Jena DDR 20927 MC Flektogon 2.4/35

1) 35mm
2) f2.4
3) Carl Zeiss Jena DDR
4) Body has some wear but overall in good condition with no impacts on the filter rim. Lens body has one ring that is marked 22 16 11 8 5.6 4 2.4 which is clearly an aperture ring. Lens body also has a part with textured surface that is obviously a grip to use to rotate the lens and that is the focus mechanism. There are no metal contacts on the rear of the lens and it has an slider button on the body marked M/A. I know that is some sort of mechanism for manual or automatic aperture (I use it on M with my modern cameras). So this is clearly an older manual focus lens. It is worth $150-250. I bought it maybe 5-6 years ago for $60-80 so it has actually increased in value. It has a bit of a cult reputation helped by both working well and by the brand name (still known today).

Lumix G 1:2.5/14 ASPH. ø46 -- on the lens side there is more text including Panasonic

1) 14mm
2) f2.5
3) Panasonic
4) Very small and light lens. Clearly plastic. Lens barrel rotates but feels like it is not hooked up to any mechanism. That is the manual focus ring. No defects to filter ring or dings.

Searching eBay for "panasonic 14mm f2.5" and filtering to sold listings indicates a range of $125-225. I paid near the lower end. Due to the small lens size and my enjoyment of the focal length (it translates to 28mm full focal), I keep it on my tiny Olympus m43 camera and use it regularly.

SMC Pentax 1:1.2/50 1434409 Asahi Opt. Co., Japan

1) 50mm
2) f1.2
3) Pentax
4) Lens is heavy in the hand. It's a lump of metal and glass. Front element is physically large. It has a large burled ring that is for focusing. When focused, at one extreme there is a slight off feeling. That indicates some potential wear, need for adjustment, or defect. Lens surfaces reflect a multiple hues of color and I know SMC means it is coated -- the colors also indicate it has a coating. Coatings appear uniform -- it's not flaking off and no damage to glass. Minimal wear to body. No metal contacts on rear (in fact, the whole rear is a all metal).

Searching eBay for "Pentax 50mm f1.2" reveals it's worth around $260-550. I'd guess that if the slight odd feeling while focusing could be removed by a cleaning/adjustment, it would fetch about $350-400 used. I paid something like $200 8 years ago so again it has gone up in value.

Closing

There is a whole lot more to learn about camera lenses. Probably the most important next is to know the difference between auto aperture and manual aperture. For instance, that Pentax 50mm f1.2 is a "K series" lens which indicates it is one of the first K mount (the prongs on the rear of the lens are the mount and K is the standard from Pentax for how the lens connects to the camera body). Later on, Pentax had an M series and then an A series. M was basically K refined and A introduced auto aperture (and some plastic).

But ignoring all that, getting a feel for quality lenses based on brand, focal length and maximum aperture will give you a very good gut level check for weather to risk $5-20 on a used lens. Just a month ago, I came across a very old Pentax lens for $10 at a local thrift store. It is an extremely clean example but not exceedingly rare but it still goes for about $70-90 on eBay. I bought it without checking because I could tell by the all metal construction (hinted by weight and feel), how clean it was (it came in the case), the fact it came with the matching Pentax-branded metal lens hood, and the fact it looked unused and it wasn't a 50mm lens that it would be worth buying. I should note that I have only found a couple of lenses to buy via thrift stores. Many have some old lenses that aren't worth any money. But I enjoy checking and maybe you might enjoy it too?

[Ego]

I have a feeling I am going to be referring to this post regularly. Great stuff. Thank you!

[Sclass]

This is really interesting. I sold off a collection of canon FD lenses on eBay before moving a year ago. It broke my heart that the equipment had such little value compared to what it had cost me in the 80s but I was glad somebody still wanted it.

Thanks for posting this. A lot of info in there. Not sure I'll get beyond my point and shoot digital cameras but if I do get more sophisticated I'll use your info. One peeve I have about my cameras is the auto focus has a mind of its own so to speak. It doesn't focus on what I want it to focus on and it will limit or increase the depth of field at the wrong times.

I recall watching my dad ruin a Nikon lens he tried to take apart. He left it in a hot car and oil oozed out on to the metal aperture leaves. Once he took it apart little shims fell out all over the place and he could never figure out where they went in. Lens was from the 1960s.

Cool that you can pull this DIY off successfully.