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FASTAX 16mm Highspeed - Model WF3


Oliver Christoph Kochs
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Hello, dear camera enthusiasts,

in the next days i will use my old 3M Wollensack FASTAX 16mm Highspeed Cam i bought on ebay a couple of years ago. Haven't used it EVER til now. Now i hope that i do everything right, and maybe some of you have worked with this before.

I am shooting the squashing of a balloon for a documentary to explain what can happen in a plane crash.

The camera is the 4 prism WF3 model that uses 16mm double perf film.

I don't have the goose unit and so i built something to ramp it up to the final speed.

We will shoot outside at noon and have some 5 Kilowatts Tungsten Lamps to "support the sunlight".

Will that be enough? And is there anything else with these models i must know when shooting.

I thank you in advance for every tip that may help here...

Oliver

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I'm sorry I can't help you with that specific camera but I'm looking forward to seeing your footage! I can share this with you if it is at all helpful -

- I chatted with the director of this video a while back and he told me they shot at 3,000fps with 30k watts of light. There's various slo-mo shots of balloons exploding throughout the video. I don't know how helpful that may be but perhaps could give you some relative numbers to help get the look you want. Edited by Jason Hinkle
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I used these cameras extensively in the synchro-ballistic mode some years ago but also did a lot of high-speed cine. If you would like to send me a private message I would be pleased to pass on some info.

 

Presumably you know that the WF3 doesn't have a regulated speed. You have to be running at the correct speed when you trigger the event. That's why we always used a sequence timer to start the camera, allowing it time to run up to speed before triggering the event.

 

The only way to calibrate the running speed is to run test films at a range of voltages and then plot speed against time- in addition to a power supply you also need to drive the timing lights which will place a mark on the edge of the film at a known frequency. If you don't run these tests you will be quite unable to achieve a predictable running speed at the time you trigger the event.

 

Assuming all this is in order, you can work out the exposure time for your desired framing rate with the 4-sided prism from the shutter factor engraved on the prism. This will be either a ratio, such as 3, or an equivalent shutter angle, such as 120 degrees. If a ratio, multiply by your framing rate to get the reciprocal of the effective shutter speed; if an angle, divide into 360 to get the ratio. I don't recall the ratio for the WF3- I never used it in the framing mode- but it will be a number like 3 or 4.

You can then work out if you have enough light with a meter but I have to say if you're expecting to run at anything over 1000fps, bright sunlight will barely be sufficient. We occasionally got away with it, but only with 400ISO stock. If you work it out at 1/3000 of 1/4000 sec that's about f/4.

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Mark and Jason, this is very helpful to me. I found out that for the WF3 a 120 deg. shutter should be used for exposure calculation. This makes a 1/30000 th of a second of time when the camera is running at its maximum speed of 6000 fps.

Although i can't control to run it at an exact speed i'll try to find out how to run it at 800 - 1000 fps. I'll do this just by using a test roll of one daylight spool and run it at different voltages. This will let the daylight spool be pulled through in 4-5 seconds. By that i'll have a theoretical exposure time of 1/5000 in the occuring event. I will have 500T double perf Vision2 that i hope is still okay after 4 years in the fridge. Hopefully i'm allowed to post the results. If there's more for me to know please hit me...

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That would be (360/120)*6000= 1/18000 sec. So 1/3000 at 1000fps.

You still have the problem of not knowing when the speed is correct; as I said, the WF3 is unregulated and will just keep on accelerating until it runs out of film. The best you can do is assume the speed-time curve is a straight line, which it will be, more or less, at the low voltage you need- and work out your notional 1000fps from that. I suggest testing voltages around 30-50V, although that is a complete guess. I've never run a WF3 that slow.

 

As to plotting the speed/time curve, and approximating it to a straight line, you know that the roll is 30m long. Say it runs through in 5 sec. Plotting speed against time, the area under the line is your 30m, so the maximum speed is half the base times the height, or 12m/sec. You can then measure off the time at which the speed will be your required 1000fps, or just under 8m/sec. I don't have my graph paper handy so you'll have to do that yourself.

Try voltages around 30-50V, although that's a complete guess. I never ran a WF3 that slow. It doesn't run well at low voltages; you really are in the dark working without timing marks.

There's no reflex focusing, so you have to focus through a loop of film in the gate; we used a special focusing film with a surface like ground glass. Chips of film may need to be removed with tweezers; at high speeds we used a vacuum cleaner.

Good luck.

Good luck.

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Oh Mark, you are so right.

My calulations were done with a stopped down lens (f4). Sorry that i forgot to write that. I will calulate, do one test and then shoot again with a fully open iris. I have parts of the manual and the curves are in there, so i'll try to measure the ingoing voltage now and hit the 50V you suggest. Thanx Mark, you are very helpful here.

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The MANUAL? Never seen one of those. That will help a lot but you still need to test-these cameras draw a lot of current so the power supply can affect the run-up and top speeds. I always had 30-60A but the manual will specify what's required. They don't always run exactly the same on diferrent supplies.

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Ah, I remember that graph, but we always made up our own from a speed test. In my day the Goose had been superseded by the CD2 made by Bowens.

Visual Instruentation must have taken on the support in the 90s- when we bought replacement Fastax 1s in 1990 at about £6500 each they were being made by Redlake, but the old grey WF3s from 1963 were mostly still going strong. Apparently the original was designed by Kodak on the 30s for Bell to study relay bounce. Bell took over the development themselves, then it passed via 3M to Wollensak.

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We just shot our highspeed footage as planned. It took a while now, but it was very sunny today and we had additionally lit with 2 silver reflectors. The 500T 2 perf didn't jam and i think it was 2000 fps at the peak of the curve when we "pulled the trigger". The photos are from our wonderful PA Iris Kreidel.

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We just shot our highspeed footage as planned. It took a while now, but it was very sunny today and we had additionally lit with 2 silver reflectors. The 500T 2 perf didn't jam and i think it was 2000 fps at the peak of the curve when we "pulled the trigger". The photos are from our wonderful PA Iris Kreidel.

 

\m/ nice!

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We just shot our highspeed footage as planned.

 

That looks interesting. What are the little yellow objects, and where were they before the ballon was punctured? They seem to be moving at very different speeds, and the lens doesn't look long enough to account for that. Please do post some frames from your high speed shoot.

 

 

 

 

Thanks --

 

 

 

-- J.S.

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  • 13 years later...

Hello to everybody.

Since so many years have passed, I don´t have a lot of hope that somebody will reply to my questions, but... I will try anyway.

I have also found one of these monster, a WF-14 to be precise and I was able to let it run, find the original lenses, film and some test film.

I have some doubt about the loading of the film. Shall it be oriented as in the following images, with the emulsion oriented to the outside of the camera? And, another question: is it correct that I shall compose the image before I load the film? Because, when the film is loaded I cannot see anything in the viewfinder anymore.

Thanks a lot, 

Marco

IMG_0990.JPG

IMG_0991.JPG

IMG_0992.JPG

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That's correct, the emulsion faces the lens.

You compose and focus before loading with a piece of frosted focusing film threaded around the sprocket and held taut with elastic bands around the reel spindles. Line up the right-angle prism in the sprocket with the gate, then close the lid and compose through the finder. Focus, then fix the focus with tape on the lens barrel, then thread the film.

You can make a focusing film by sanding down a piece of clear film about 20 frames long until it is translucent. Fold over and punch the ends for the elastic bands, then draw a thin line with a fine Sharpie on the sanded side so that the eye has something to fix on for focusing.

Your threading path looks OK but I can't be sure as I can't see enough of the camera.

Are you sure you have a framing camera? Some were modified for synchro-ballistic photography and don't have a prism at all. If the gate mask has a narrow slit rather than a 4:3 gate mask, you have one of these and it won't produce individual frames at all. But ours were WF3s with 100' capacity- I think the WF14 is 400'.

 

Edited by Mark Dunn
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Hi Mark, first of all thank you very much for having replied to me! I really appreciate that!

That's correct, the emulsion faces the lens. Your threading path looks OK but I can't be sure as I can't see enough of the camera.

Good, at least I did not make a macroscopic mistake, even if this was just a test. It is really an experience to see 30 meters of film running in about 3 seconds! I can make more photos of the whole film path tomorrow and post them here. The camera is hosted in my office because it is really huge and heavy. 

You compose and focus before loading with a piece of frosted focusing film threaded around the sprocket and held taut with elastic bands around the reel spindles. Line up the right-angle prism in the sprocket with the gate, then close the lid and compose through the finder. Focus, then fix the focus with tape on the lens barrel, then thread the film. You can make a focusing film by sanding down a piece of clear film about 20 frames long until it is translucent. Fold over and punch the ends for the elastic bands, then draw a thin line with a fine Sharpie on the sanded side so that the eye has something to fix on for focusing.

Now I understand why I have found a short piece of "focusing film" with the accessories: I did not checked it yet carefully, but there is an envelope on which it is infact written "focusing film". I must check it more carefully. But I am a bit puzzled, because, also without the focusing film, I was able to see an image in the viewfinder and focus it. Basically, I put the lens, lined up the right angle prism to let the light reflected inside the viewfinder, found a target and focused on that. Now I can guess that I shall focus on the surface of the focusing film instead? Was I focusing on a wrong focusing plane? (sorry for the stupid question...)

Are you sure you have a framing camera? Some were modified for synchro-ballistic photography and don't have a prism at all. If the gate mask has a narrow slit rather than a 4:3 gate mask, you have one of these and it won't produce individual frames at all. But ours were WF3s with 100' capacity- I think the WF14 is 400'.

Well, I am afraid to tell you that... I don´t know what do you mean with framing camera. My WF 14 is basically this one:

https://alphaxbetax.files.wordpress.com/2019/10/1955-fastax-high-speed-motion-picture-oscillographic-cameras.pdf

of course I can make more photos tomorrow and put them here. The film capacity is 400 feets (but now, for convenience and also because I could only find limited quantity of double perforated films, only available in 30 meters spool, I am using 30 meters of film only). 

 

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I just want to say that I was letting the film running at high speed and I did not have any issue. The next step will be to find a relationship between input voltage and frame per seconds, but this doesn´t worry me, because I will also follow the indications mentioned above in this topic. I am just not rather sure about focusing. I attach another photo of the focusing film.

IMG_0997.JPG

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>> Well, I am afraid to tell you that... I don´t know what do you mean with framing camera. My WF 14 is basically this one:

Cool! I have one of these in a box somewhere! Never did get to use it, sadly.

Anyhow, there were a few different options for the drum cameras, they were available as "framing" cameras or "streak" cameras.

Framing cameras... well, they basically make individual frames, like normal film cameras. They are for high speed cine work.

Streak cameras, on the other hand, move the film continuously behind a thin slit. This is useful for certain technical applications where you're photographing linear motion. It's basically a long still photograph *of* time going by, but it won't make sense as a movie.

One common example of streak photography is the photo finish camera at a horse race track. Check out this cool write up for more insight into how it works... https://www.donttakepictures.com/dtp-blog/2019/5/8/winning-by-a-nose-the-history-of-the-photo-finish

Anyhow, you can easily tell what kind of camera you have if you take off the lens port and look inside while you turn the drive sprocket. If you see a prism spinning in there behind the lens, you have a framing camera.

The prism is geared to the drive sprocket and turns in sync with it. Light going through a square prism displaces the image as the prism turns through an angle (you can see this effect looking through a thick sheet of glass). This "sweeps" the transmitted image vertically along the face of the film on the sprocket behind the prism. The image moves along at the same speed as the film on the drive sprocket, that way the image stays sharp(ish) and the film never has to stop.

As far a focusing, when you look through the finder, yes, you may see an image even if you don't have focusing film in the camera. The lens is always making an image at the focal plane, even if there's nothing there to show it (an aerial image hanging in space). 

But you still want to use a piece of focusing film because it's impossible to tell where exactly the plane of focus is with any precision. The focusing film behaves like the ground glass in a view camera, acting as a placeholder for the exact plane the film is soon going to occupy. You want to be careful that you place the frosted side (and therefore your focal plane reference) facing outside on the drum, where the emulsion side of the film is going to be.

As for framing... mine has a circular hole that shows most(ish) of the middle of the frame, but you don't really know where the exact frame lines are. At least you can find the center and this was probably plenty good enough for the original technical applications.

 

 

 

  

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By the way, that black thing the film runs through just before the first roller might be a timing light.

A lot of these cameras were used for industrial measurement, so it was important to know how fast they were actually running (which was at best an educated guess). Many of them were equipped with a little neon bulb that would flash at a certain rate, say, 100 times a second, and put a steady timing pip on the edge of the film so you could measure exact event timing.

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Hi Steve, thank you for you reply! 

Together with the camera, I have also got several accessories and also a film which I have scanned with my DIY 16mm frame by frame scanning machine. You can find it here: 

There is an introduction, where they show the experimental apparatus and then the section dedicated to the experiments itself. It shall be some metal deposition on filaments used for vacuum tubes (I am still trying to get in contact with the person who made it, because he is still alive and could perhaps give some more information). I think that the section which is dedicated to the experiment was made with this high speed camera. The film is infact composed of several pieces which were merged with a splicer.

Mine shall be a framing camera, because there is the rotating prism. I have also found the following schematics, which shall confirm my hypothesis. There is the possibility to add a second trace (at the time the one from an oscilloscope) from an auxiliary optical path: 

308461652_1087562991906902_8575861918855740688_n.jpg.fa7caaec060c4da9327e113e91ab5d64.jpg

Thank you for the hint about focusing, probably, without this tip I would have made the focus on the wrong plane!

And yes, I also have some spare lamps for the time marking, but at this stage I don´t think I will use this function.

Edited by Marco Leoncino
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4 hours ago, Steve Switaj said:

that black thing the film runs through just before the first roller might be a timing light.

There is one, but it's the block below, after the sprocket, with the wires. Unless Marco has the control box for the timing lights they won't work anyway. The frequency would be 1kHz for speeds above about 100pps and 100Hz below. I think the block above the film is the prism for the oscilloscope trace.

You cam compose quite accurately if you  line up the red mark on the sprocket with the white line on the gate block- both visible in your third photograph.

As Steve says, the eye will focus almost anywhere, especially if you have good visual accommodation, unless you use the focusing film. I found that drawing a line on the frosted side helps as well. You can use a sharp pencil if you don't want to mark the film permanently.

I believe your threading path is correct, but as the WF14 was intended for 400' spools it may not run well at high speeds with a 100' load. But I would think it would certainly be OK at up to 1000pps. Make sure the spools are in good condition and not bent or damaged in any way.

Make sure the switch to the right of the timing block is working- it is held closed by the film edge and cuts off power when the film runs out. Otherwise the camera will not stop. unless you switch it off.

Edited by Mark Dunn
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Thank you so much to everybody!

I don´t have the control box. I had to rewire most of the cables, because some where very worn. I am able to let the camera run well and to use the switch which stops the camera when the film is finished. I have to say that I am already happy!

The most complicated thing in these times is to find 2R film. I bought some Foma R100 and some old ORWO N74 perforated on both sides. 😪

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