Remove Hard Stops From Nikkor Lenses?

[M Joel W]

I'm going to be shooting somethinge either on a mini35 or a Red camera using Nikon lenses. However, I need to do a shot with a rack aperture--along the lines of one of those shots that begins indoors then whip pans outdoors. But I can't mask it or do it in post--just trust me on that one. I also can't rent lenses; just trust me on that one--I need to buy the lens and it needs to be under $1,000 and faster than t2.0.

 

I'd like to just remove the hard stops from a Nikkor and install a focus ring; is there a way? Otherwise, are there any fast lenses under $1,000 with decent optical performance?

 

 

Thanks...PM me if you want details of the shot, but just trust me on this one.

[K Borowski]

Otherwise, are there any fast lenses under $1,000 with decent optical performance?

 

No offense, but you're kidding, right? I have no idea how much money you're rolling in to ask that question, nor have I ever invested-in or used any Carl Zeiss or Hasselblad lenses, but let me assure you, there are plenty of lenses that can give "decent performance" for under $100. Also, why would you buy lenses anyway for dramatic productions, when you can rent far better ones (unless you've inherited $10,000,000 and have $1,000,000 that you've allotted just to lenswear).

 

This is a still lens, so it's obvioulsy not adjusted for focus breathe, but I've seen gently-used Canon 80-200mm F/2.8 zoom lenses (I'd assume the T stop is pretty close to 2.8, I doubt any lower than 3) go for $500. This is arguably the gold standard for zoom lenses in still photography, although there's a newer version now that has optical image stabilization.

 

In the cinema world, I understand that zooms need more demanding production requirements to deal with the (near) lack of cropping in filmed movies, light falloff over a zoom arc due to internal optical reflectance, and individually adjusted and calibrated manual focus/T-stop rings to again ensure the utmost in accuracy, but again, those are the ones you want to RENT.

 

Prime lenses, on the other hand are affordable (I've seen sharp 16mm prime lenses go for under $100, although I'm sure that more recently-manufactured primes, due to smaller demand for 16mm after the arrival of video, would probably be 2 or 3 times that.)

 

I do own one zoom lens, a 12-120mm Angenieux F2.8, and I honestly couldn't tell the difference between footage I've shot with it and that with Zeiss primes, unless you're talking about non-nighttime scenes I've shot wide open.

 

I've already spent a lot of time typing in lens formulas on this forum this week, so I'm not going to repeat them again here, but, unless you're shooting scenes with 1000:1 contrast in them, the theoretical sharpness of a lens lens, while very important, is no where near as limiting on the detail you are able to resolve as the area of the image capture medium, followed in second by the resolving power, at 1.6:1 contrast of said medium. Practically, the sharpness of an image is controlled by subject contrast, the f-stop (two down from wide-open is your friend, but there are plenty of decent lenses that shoot fine wide open, again especially primes), the range of distance, your filtration (if any), and most important your focus puller's skill (you *are* doing that manually right? If not forget about buying any more lenses right away).

 

While obvioulsy moviemakers appear to have access to far more money (at least at the upper eschelon) than still photographers in similar high levels of the multimedia industry, I'd say that with moving images, fine detail is LESS imortant because of your ability to tell the story over time, and conventions like closeups, zooms, etc which the viewer then will almost always infer to be the same as an overlaid long or master shot, even if the detail in the master shot isn't high enough to tell one face from another. Also, because an individual frame from a movie is on the screen for at most 1/12 of a second during viewing, the human eye can't even fully take in all the detail that you present it in a static shot anyway.

 

I agree that you can't digitally adjust F-stop (especially to reveal detail that was so underexposed to begin with it doesn't register on the film or tape anyway), but have to question your inability to rent (again you could adapt a 35mm still lens, which really is something you can find ANYWHERE) and rent for very reasonable rates, $8/day or less.

 

So, OK, if you can't rent lenses, you can get a 50mm lens that fits your F-stop requirement for probalby $20 tops on eBay, maybe $30-50 at a camera store near you.

 

For a cinema lens, I'm sure you could find older used 35mm prime movie lenses going for less than $100 that are 2 or better. You'll just have to accept slightly older glass, which I would say is really of no practical concern. Yeah, primes aren't as dynamic and versatile in a crunch as zooms, but the wonderful thing of dramatic filmmaking is that there's no end to the amount of things that can be done on the screen with a little bit of teamwork, practice, and coordination (they didn't use a zoom for that famous long sequence from the film "Soy Cuba", it was all camera movements (even involving seamlessly switchign camera operators at spots) and sone ingenuity with equipment improvisation.

 

And (your post gets more confusing the more I read it, I still don't completely understand what you are going for) why do you NEED a rack aperture. That is a luxury of a high budget, not a necessity. As long as the person pulling focus knows what he or she is doing and has an opportunity to rehearse the pull a few times, you should be able to perform it flawlessly almost eery time when doing the actual shooting with practically any lens. It's more complicated twirling two rings by hand and getting the timing so that both are done smoothely, but certainly not that difficult to nail after a few tries.

 

As for modifying a Nikkor lens, unless you're a skilled optical machinist with experience designing lenses, constructing them, and aligning lens elements, with access to all of the precision equipment necessary to retool a lens, otherwise, that operation may cost you more than the $1000 you want to spend on the lens.

[Mike Rizos]

You need to remove the lens mount held by three, four or five screws. These screws strip easy, make sure you use the correct screwdriver. Note the position and pull the aperture ring out off the back of the lens. Aperture indents are achieved by a small strip of metal held by two srcews, located on the lens barrel underneath the aperture ring. After removing this, place the aperture ring back in the exact position it was.

[K Borowski]

You need to remove the lens mount held by three, four or five screws. These screws strip easy, make sure you use the correct screwdriver. Note the position and pull the aperture ring out off the back of the lens. Aperture indents are achieved by a small strip of metal held by two srcews, located on the lens barrel underneath the aperture ring. After removing this, place the aperture ring back in the exact position it was.

 

Coming from someone that has ruined a lens aperture (making the lens a really terrible paperweight, because I got angry and broke somethign every time I needed to weigh paper and picked the thing up ;-) ) you probably do NOT want to risk doing permanent damage to a lens by dealing with carefully aligned internal components. Again though, if you buy 20 lenses for what you were going to spend on one, you could learn by trial and error on 19 and hopefully get it right at least on the last one ;-)

 

Quoted the wrong quote, reason for edit :-(

Edited April 14, 2007 by Karl Borowski

[Hal Smith]

I wouldn't recommend messing with any lens that is of any value. I got a really nice Cooke 25mm SP Series 3 for cheap because an otherwise intelligent Cinematographer had pulled the close focus stop to get it to move in a little closer. As a result he jammed it. I took a chance on it, bought it, and fortunately Guy at ZGC was able to unstick it and collimate it for their normal collimation charge. Whoopy! :)

[Patrick Neary]

I'm going to be shooting somethinge either on a mini35 or a Red camera using Nikon lenses. However, I need to do a shot with a rack aperture--along the lines of one of those shots that begins indoors then whip pans outdoors. But I can't mask it or do it in post--just trust me on that one. I also can't rent lenses; just trust me on that one--I need to buy the lens and it needs to be under $1,000 and faster than t2.0.

 

I'd like to just remove the hard stops from a Nikkor and install a focus ring; is there a way? Otherwise, are there any fast lenses under $1,000 with decent optical performance?

Thanks...PM me if you want details of the shot, but just trust me on this one.

 

Maybe it's too early in the AM, but am I missing something here? just pull the iris with the pan. Start at 1.4 or whatever and pull to 11 or whatever. People do it all the time. Why do you need to pull a lens apart for that?

 

And no, an iris pull isn't a "luxury of a high budget"....

[Hal Smith]

Just a guess here. If I had to do a whip pan from an interior to bright sun outdoors, I'd try placing a large ND filter on a c-stand so it was in front of the lens when I panned to the exterior. No iris pull required. If the pan was slower than a true whip, I'd try a large ND grad instead. You may have a problem with reflections off the filter and have to work out placement of a black flag or two but I think this idea would be worth trying - after all, rental filters and c-stands are pretty cheap. You could test the idea even cheaper with a piece of ND gel, some sort of stand, and a roll of black gaffer's tape.

[Kevin Zanit]

He wants to remove the stops so that when he does the iris pull it will be smooth rather than jumpy when the ring pauses at each "hard" f-stop stop.

[Patrick Neary]

Oh it was too early...

 

It seems like a lot of effort for not much reward though. Nikkor detents aren't that sticky, although I guess it makes 1/2 stops harder to hit. I would think any decent local camera repair shop could do this for not much money.

[M Joel W]

You need to remove the lens mount held by three, four or five screws. These screws strip easy, make sure you use the correct screwdriver. Note the position and pull the aperture ring out off the back of the lens. Aperture indents are achieved by a small strip of metal held by two srcews, located on the lens barrel underneath the aperture ring. After removing this, place the aperture ring back in the exact position it was.

 

Thanks, this is the answer I needed. I'll probably end up using a 50mm f1.2 so I'll maybe ask a professional lens tech to do the work since it doesn't sound that hard but it does sound like something I could screw up.

 

For everyone else who responded, the actual shot is a bit different from what I described, but suffice to say I need an extremely fast lens that I can buy and modify myself....and afford for my short thesis film (with a budget around 5 grand but with some free equipment from my school).

 

And thanks again to everyone who responded.

 

And on the subject of lens sharpness, I've been using a set of AI and pre-AI nikon primes lately with my digital rebel XT: 28mm f2.0, 35mm f1.4, 50mm f1.4, 85mm f1.8. All of them are soft wide open, the 35mm f1.4 unusably so, and all of them exhibit major chromatic abberation. Still, they have a much nicer look than the kit lens that came with the camera...but I wouldn't want to shoot 4k using them, except perhaps at f2.8.

Edited April 15, 2007 by Matthew Wauhkonen

[Patrick Neary]

the other thing to remember about nikkors is that you almost have to look at each one individually. One 85mm 2.0 might be a stinker and another might be great, and that was out of the box. Add a few years of hard living to that and each lens becomes a unique beast.

[M Joel W]

the other thing to remember about nikkors is that you almost have to look at each one individually. One 85mm 2.0 might be a stinker and another might be great, and that was out of the box. Add a few years of hard living to that and each lens becomes a unique beast.

 

So true. My 35mm f1.4 was like new (I would not have questioned its newness had it been sold as new) and it's a piece of junk wide open. Most of my older lenses are much better. Thankfully my lenses all have similar warmish/neutral color casts, although an older 35mm f1.4 I tried was bright yellow and a newer 28mm f2.8 E series was quite cool. That said, for the price, these lenses are fantastic.

Edited April 15, 2007 by Matthew Wauhkonen