Adjusting zoom

 
For posterity sake… please let me know if you want to take this down.

Focus adjustment of a zoom lens: Kiron 35-135mm f/3.5-4.5
by Henry Taber

Zooms must be adjusted for infinity sharpness at both extremes of their zoom range. The wide angle adjustment is made by moving the rear element assembly closer or farther from the film plane, while the telephoto adjustment is made by moving the front element assembly. It is often necessary to readjust (perhaps several times) until infinity is sharp in both positions. If focus is sharp in both extremes the middle ranges will be sharp automatically.

On this Kiron, turning the macro ring moves only the rear element assembly so it is used for the wide angle adjustment. The macro ring is secured to the macro helix by three setscrews (blue arrow). Turning the focus ring moves only the front element assembly so it’ll be used for the telephoto adjustment. Pull back the rubber hand grip as shown in the picture to expose the six setscrews (yellow arrow) securing the focus ring to the front element helix.

Sliding the front of the lens in and out (zooming) moves all elements.

The zoom/depth of field cylinder moves with the macro helix and is retained to it by three setscrews (green arrow). So if the macro ring must be repositioned in the course of wide angle adjustment, this cylinder must also be repositioned. But repositioning it can wait until all adjustments are finalized. It serves no mechanical function and its position does not affect focus.

Mount the lens on a camera body and either sight a very distant, high contrast object or use the technique of backsighting described in the test equipment section of this website. See Collimator article.

Now that you have a bit of theory the adjustment procedure becomes obvious.

First adjust the widest angle zoom position. Verify the macro ring is in the zero detented position, then zoom to the 35mm position and turn the focus ring to infinity. During all adjustments the focus ring must be against the infinity stop. The distant object should be sharp. If not, turn the macro ring until it is sharply in focus (red double arrow near camera body). If the macro ring must be turned beyond the zero stop to achieve sharpness, loosen the three setscrews (blue arrow) on the ring until the ring freewheels. Then back it up a ways and snug up one setscrew. Turn the macro ring until focus is sharp. After verifying that the telephoto focus is also sharp, loosen the snugged setscrew and return the macro ring to its detented zero position.

To adjust the telephoto infinity focus, zoom out fully to the 135mm position. The distant object should be sharp. If not, loosen the six setscrews (yellow arrow) and turn the outer ring (red double arrow near front element, not the focus ring, it stays against the infinity stop) until focus is sharp. Snug one setscrew and recheck wide angle sharpness.

When both wide angle and telephoto focus is sharp, retighten all setscrews and reposition the zoom/depth of field cylinder so the line coincides with the infinity mark.

Soligor serial numbers

Soligor serial numbers to certain manufacturers. (It’s much easier with Vivitar lenses BTW.)

But this seems to be kind of reliable due to intensiev research of some lens enthusiasts at MFLenses (Thanks!):

Soligor Codes

1 = Tokina
2 = Sun
3 = Sun
4 = Sun
5 = ??? (perhaps Samyang)
6 = Komine
7 = Sun
8 = ???
9 = Kino
31 = ??? *
A = Komura #
H4 = Kawanon ? #
H5 = Komine #
H6 = Komine #
H7= Tokina #
H37 = Kawanon? #
M = ??? #
N = ??? #
R = ??? #
T = Tamron #

Code system. First number = Maker.
Second number = Decade
Third number = Year

*Six digit lens date code unknown.

# Letter code lens date code unknown.

“H” prefix brands:
Lentar / Focal / Soligor / Sun / Vemar

Soligor lenses were alse branded and sold as:

Reflex, Super Carenar, Prinzflex, Weltblick, Mirage, Infotar, Hanimar, Flexar, Elicar,Derek Gardenar, Porst and possibly Bushnell (Bausch & Lomb ), J.C. Penny, Pallas, Berroflex and Aetna.

You know you’re a photographer when…

You know you’re a photographer when…

You know what aperture-priority means.
No one else brings a camera to an event if they know you’re coming.
You have thousands of pictures and you’re not in any of them.
When you lose track of a dramatic conversation between two characters in a movie because you’re too busy paying attention to the nice bokeh behind them….
…when you start enoying your photos as photos, rather than pixels.
Your baby’s first full sentence is : “STOP taking pictures!!”
When your cameras, lenses, and computers are the most expensive things you own
when you drive by a frozen over ugly marsh of broken down trees can visualize the beautiful finished image.
When you stop saying “on the count of three”
When your CEO walks into the office and asks “Anybody here who’s familiar with digital cameras?” and all eyes turn to you…
When the UPS man says ” See ya tomorrow”
You walk into a building looking for composition angles….
at a wedding all you can think about is what shots the other photographer is missing
you have to consciously “switch-off” critique-mode when looking at friends’ snapshots
You do not need a software to make your photograph good…
your friends don’t even notice you taking photos of them anymore
You think about what manual settings you should use when you see something interesting.
you get angry when other people ask you why your prime can’t zoom
you get pretty annoyed after the :”Wow, that camera takes awesome pictures!! How many megapixels?”
you’re crazy about bokeh.
you realize HDR is to photography what autotune is to music.
Christmas lights? Bokeh.
you get scared when people ask if they can hold your camera..
Fast glass excites you.
Your friends have begun to hand you their cameras at social gatherings when they want a good picture taken.
Your kids have stopped fussing about being photographed because you work faster.
Your in-law who’s a pro shares fewer and fewer tips with you.
You stop asking what aperture and shutter speed was used to take a picture.
You are unashamed to carry a point-and-shoot — even at events crawling with other photographers.
Your spouse stops asking what FedEx or UPS delivered.
your 2-year-old counts like this:  ”1.4, 2.0, 2.8, 4, 5.6, 8, 11, 16, 22.”