| Vivitar 90-230 f4.5 Zoom. When cheap is uhm, "cheap". | |
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Specs: 90-230mm vari-focus zoom sample images. 1. Blurry pictures of the product. |
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Sometimes you have to have to pay attention to what the seller is NOT telling you. Of course, to know that you have to research the lens on your own, discover it's weaknesses, and see if that has been addressed by the seller. For example, many users report that some russian portrait lenses tend to have poor lubricant and focus can be rather stiff to the point of distraction, ("russian glue" as seller 'Doubice', puts it). In which case you might see "clean optics", "mint condition", and "no mushrooms", but nothing about stiff focus. Therefore, you have to ask. Reputable sellers know this is matters and will give full disclosure. Even so, having the all the bases covered, and research reveals that a particular lens to be a gem, or "sharp", etc. You still have to assume that old and used, is well, "old and used." The zoom range is very useful. 90-230mm is 230/90=2.55x zoom factor. (Usually anything more than 3x zoom factor presents issues with distortion). On a DSLR with 1.6x crop factor it becomes a 144-368mm. Good for bird watching. Combine that with it being a Vari-focus lens (you have to refocus after zooming), it should be as sharp as or nearly as sharp as a prime lens. The vari-focus olympus 28-28 f3.4-4.5 is considered a prime lens by some posters. Before I purchased this lens, I've read other users being "mildly surprised" as to it's sharpness and performance. So, I bid, $5 bucks and it was mine.
What a dog. I can't get a decent sharp image from it. Color is nice, and with an 8-bladed aperture it has decent bokeh, but after a few hours shooting both on and off a tripod, (including some carefully balanced studio shots). Curiously, I shined a light through the lens at an angle, and noticed a rippled texture. Using a scope I spotted fungus and presumably, a clear thin coating. Zooming into my images at 100% I noticed a double or ghosted image. Even on a tripod shot with remote trigger the effect was present, ruling out vibration and shake. Update: I disassembled the lens and it turns out that my 'fungus' was a dead bug, and a layer of dirt or crud, and that a quick cleaning was in order: 1. Using a spanner wrench, I removed both the front element retaining ring, and the rear element assembly. 2. Next I removed the focus ring stop screw...
...and unscrewed it from the assembly.
3. Next I removed the forward focusing element assembly screws, (there are two):
... and the front focus assembly slides out easily.
4. I removed the access cover screw from the tripod collar ring.
5. Then removed six screws around the circumference of the middle assembly:
7. Now I had access to the dirty, bugged assembly. This assembly was froze and nearly bent the tines on my spanner wrench. So I added a few drops of liquid wrench, then opened up the access holes to accommodate a larger, and stronger spanner wrench:
Here we can see the real issue in all it's gory:
All cleaned up, reassembly was a snap.
The results were mixed. Careful comparison at 100% revealed improvement, and less ghosting. However, the edges were still a tad soft (see 100% crop):
What can I say for $5? (Next!) Before this maintenance, I did manage some interesting shots that qualify for 'artistic merit', and reasonable sharpness (small jpegs online are very forgiving of issues otherwise seen full screen). Furthermore, being that it's a T4 lens with an interchangeable T4 mount in m42 thread. I can keep the mount and shop for other lenses that use the same mount and do a swap. In conclusion: If you're not too crazy about playing vintage lens roulette, then you might consider buying from a reputable dealer whom will guarantee the condition and performance of his lenses. Such dealers will often repair, re lube and actually test the item. Of course, these will offered at a much higher price, and maybe a few hundred dollars for an old lens is a bit much for some. However, you could easily spend that much on a few lenses and shipping, and risk a pile of junk for your efforts. One last item of importance. Although I like vintage lenses, I would never consider using a vintage lens for a paying gig that involved sports, product, or commercial photography. These kinds of jobs are best served by the quicker, and brighter autofocus lenses. Portraits and groups might be an exception, where things aren't so rushed. Still, it's best to bring backups just in case the thing falls apart while on-site. Let's take a look at that few shots that worked. |
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