Degrees of Focus Ring Rotation: Are the "non-AF NIKKOR lenses "Long Throw."

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Ripple

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Degrees of Focus Ring Rotation: Are the "non-AF NIKKOR lenses "Long Throw."

Hello,

I'm tossing around the idea of a follow focus system. Looks like the RedockMicro microFollowFocus steps down rotation by about 1:2, so the follow focus ring moves about 2x's the degrees of the focus ring on the lens. (I guesstimated this ratio myself, by calculating the number of teeth that "would be" on the focus ring gear attachment, if the gear had teeth all the way around. Please correct me if you have a more accurate ratio for the Redrock system).

Anyway, a 1:2 step-down is not enough for my purposes. Need lenses with longer manual focus ring throw.

Does anyone here know the throw of any of the current "non-AF NIKKOR lenses."

I would be particularly interested in the

24mm f/2.8 or 28mm f/2.8

and the

50mm f1.4 or 50mm 1.2

Additional info:

Apparent the Zeiss lenses shown herehttp://store.redrockmicro.com/Catalog/Zeiss-35mm-Lenses vary quite a bit in focus ring throw (ZF.2 series). Don't quote me but, it looks like they're roughly:

28mm f/2: 90 degrees throw
35mm f/2: 90 degrees throw
50mm f/1.4: 180 degrees throw
85mm f/1.4: 120 degrees throw

Hoping to get something closer to 180 degrees than 120 degrees of focus ring throw.

Thanks in advance
 
The 50mm ƒ/1.4 G Nikkor is about 180°. It doesn't have hard end-stops, sadly (it's a full-time manual override lens). I don't have the others, sorry.
 
I've used Nikkors for the past 25 years for motion picture work and their biggest drawback is the small focus travel.

One possible solution if you want more turns for you follow focus is to buy gears with a larger diameter. These are goofy (and I have never tried them) but they will definitely give you a more optimal number of "teeth" for the range of focus:

http://www.dvcity.com/dvshop/A-set-of-6-gear-rings-dia-55-65mm-for-follow-focus-0.8-mod.html

Or something like that which has a larger diameter than the flush mount gears.
 
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JonathanS and mathew77,

I apologize that it has taken me so long to respond. I'll follow-up again by the end of Tuesday.

JonathanS said:
The 50mm ƒ/1.4 G Nikkor is about 180°. It doesn't have hard end-stops, sadly (it's a full-time manual override lens). I don't have the others, sorry.
Click to expand...

I actually have this lens. I use it only on a crop sensor body (D7000), so I don't know if it has more "useable throw" on a full sized sensor body. I just took some "measurements."

First of, wow, the focus ring really does travel a little over 180 degrees. Problem is, there's only about 45 degrees of "usable focus." If I focus 4 ft. away (FoV = 2 ft., the focus ring travel is a little over 45 degrees from there to infinity. If I focus 6 feet away, teh focus ring travel is a little less than 45 degrees. (I actually would almost never focus on something with a FoV of less than 3 ft.)

1. Question: How much focus ring travel does this lens have when mounted to a full frame (FF35) body, from 4.3 ft to infinity (FoV 3ft. to infinity)?


matthew77 said:
I've used Nikkors for the past 25 years for motion picture work and their biggest drawback is the small focus travel.

One possible solution if you want more turns for you follow focus is to buy gears with a larger diameter. These are goofy (and I have never tried them) but they will definitely give you a more optimal number of "teeth" for the range of focus:

http://www.dvcity.com/dvshop/A-set-of-6-gear-rings-dia-55-65mm-for-follow-focus-0.8-mod.html

Or something like that which has a larger diameter than the flush mount gears.
Click to expand...

mathew77,

Sounds like you liklely have a lot of experience with different Nikkors.

2. Question: Are the screw-driven AF lenses more accurate than the "G" series?

3. Do you know of any follow focus systems that do a (much higher gear down ratio than the Redrock)? it appears would need a 4:1 ratio to get 135 degrees to 180 degrees of usable throw on my 50 mm 1.8D, for example.

4. Which follow focus system do you use. Do you use a crop sensor or FF35 body?

Anyone else's imput is welcome.

Thanks!
 
I think older AF lenses designed for film had decent focus throws and hard stops. I have the 50mm 1.8 af it appears to be a full 180 degrees. My 24mm 2.8 manual seems to have slightly less. I have an old cheap push zoom 70-210 that also has a good long focus throw for an af lens. I haven't tried any of these for video yet as I don't have a capable camera yet. Hoping for a gh2 by summer. On the flip side some zooms have horribly short focus, I have a 28-200 tamron that would probably be useless for video given a focus throw of well under 90 degrees, the slightest nudge and it it out, I like to manual focus on stills but I've given up on that lens, not being able to zoom in full to focus then pull back like on video cameras is the biggest problem with still lenses.
 
dop16mm said:
I think older AF lenses designed for film had decent focus throws and hard stops. I have the 50mm 1.8 af it appears to be a full 180 degrees. My 24mm 2.8 manual seems to have slightly less. I have an old cheap push zoom 70-210 that also has a good long focus throw for an af lens. I haven't tried any of these for video yet as I don't have a capable camera yet. Hoping for a gh2 by summer. On the flip side some zooms have horribly short focus, I have a 28-200 tamron that would probably be useless for video given a focus throw of well under 90 degrees, the slightest nudge and it it out, I like to manual focus on stills but I've given up on that lens, not being able to zoom in full to focus then pull back like on video cameras is the biggest problem with still lenses.
Click to expand...

Thanks dop16mm,

I had not thought of looking for "out of print" Nikkors, but the 28mm 2.8 and 50mm 1.8 look like they might work, if they're reasonably priced and available (I came to still photo from video, and I've never bought used lenses).

If you happen to have the time and interest for a quick test of these lenses, I have a couple questions...

5. What is the focus ring travel from a field of view (FoV) of 3 feet to infinity (on full frame or 1.5x crop body)?

Just to be clear, the focus distances that correspond with a FoV of 3 ft. are (rounded to the nearest inch):

Full frame body with the 50mm: distance = 4 ft. 3 inches.
1.5x crop body wth the 50mm: distance = 6 ft. 5 inches.
Full frame body with the 28mm: distance = 2 ft., 5 inches.
1.5x crop body with the 28 mm: distance = 3 ft. 6 inches.

(Hope the FoV to distance conversions don't insult your intelligence -- I probably screwed up the math anyway.) ;)

BTW, is there a Nikon adaptor coming out for the GH1/GH2 by summer? I know one's due for the AF-100, after the Cannon adaptor.
 
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Wow. Thanks. Many of these have focus throw from 180 degrees, some up to 230 degrees.

I have an e-mail in to find out the usable focus ring throw for the Zeiss 50mm f/1.4 ZF.2 (I'm defining "usable" as focus ring throw from DoF of 2 ft. to infinity).

Will post when I get a definitive answer.
 
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