Vivitar was an innovative company. It designed some of the memorable lenses that destined to be cult classics decades later. They often introduced lenses that no one else has in the market. The 35mm f1.9 and the Series-1 28mm f1.9 arr two examples.
Everyone says the S-1 28mm f1.9 is a very good lens. What about the older 35mm f1.9?
I happen to like the 35mm f1.9. It's a very fast lens in its day, and while everyone made a 35mm f2, Vivitar made it 1/3 faster. Made entirely of glass and metal, this 35mm f1.9 lens is large for this focal length. Heavy and very well made, it puts the Canon 35mm f1.4L to shame, in terms of built quality. It's physically a very long lens at 7.5cm for the Nikon F-mount. In comparison, the Contax 35mm f2.8 is roughly 5 cm. Of course, built quality means nothing if the optical quality is not there. Fortunately, the lens is quite decent in this department too.
One way to judge if someone is insane, is to see how many copies of a particular lens (or any object) he/she has. I have three copies of the Vivitar 35mm f1.9, two Nikon F-mount and one MD mount, so I think I qualify for being insane. But that also shows how much I like this lens, and that it's relatively inexpensive. I got mine before everyone and their grand mother got into manual focus lenses with their DSLRs, so price was very reasonable. All three lenses were made by Komine, one of my favourite manufacturers for Vivitar lenses.
Can you shoot it at f1.9, or is just for shows? Well, even the very best of lenses performs better when stopping down a bit. The Vivitar 35mm f1.9 was not considered an expensive or professional lens when new, but I am surprised that is as good as it is, considering its age. Like so many consumer grade lenses, wide open shows lack of contrast, but holds good details, and is sharp enough to be usable at the center. Some colour fringing with strong back-lit objects, which is quite common as the coating of the older lenses were not as good as they are today. don't feel bad about it, even the very expensive 35mm f1.4L is not immune to colour fringing at wide apertures, and it's pretty easy to remove in post processing. If you shoot people or none reflective subjects, the low contrast may not even be very noticeable. Below is a 100% crop of a picture shot at f1.9:
100% crop at f1.9. Not stellar, but workable -- Canon 550D & Vivitar 35mmf 1.9. Larger.
The lens becomes quite sharp after f4, but softens up after f11 due to diffraction limits. F5.6 and f8 are sweet spots. The micro contrast is not very high to give that biting sharp perception, but it's very acceptable.
Wide angle lenses usually are not great with bokeh, but of course there are exceptions. This Vivitar is average according to my preferences. At wide open, it shows strong double-line affect. Some will find this every objectionable, but stopping down just half a stop will help make it look more natural.
Bokeh at f1.9. Note the strong double-line effect of the rings -- Panasonic G1 & Vivitar 35mm f1.9.
The far edges, on the Canon 550D, becomes reasonably sharp after f8. I am sure it will look worse on full frame. Sometimes, you will forgive the lens' slightly optimal performance because it's so well made and feels so nice in your hands. If you even get hold of one, you will agree that it's one heck of a nicely made lens.
GO Train -- Canon 550D & Vivitar 35mm f1.9.
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