combating serious vibration

[adrian tyler]

i'm embarking on a new project photographing power stations and i've run into a serious problem, vibration.

as turbines are an vital part of this industrial process i have to devise a way to combat the vibration that they produce, infact these things create so much vibration that the buildings they are situated in are deisigned with elastic foundations, if not the structure of the rest of the plant would be damaged...

so anyway, the scene: limited light, say 5.6 at 1 second, 400 asa, infernal noise and vibration.

short of taking a big strobe setup, i can't think how to get round it, i don't think that the locals would be too happy to shut down a 3mw reactor down for a couple of hours!!!

[Frank Petronio]

Get further away and use a longer lens?

I really don't know what else you might try other than a Ken-Lab Gyro on a smaller format camera...

http://www.ken-lab.com/

[N Dhananjay]

Try taking a bunch of sandbags. Mount the tripod legs in the sand - they should absorb a lot of the vibration. Good luck, DJ

[GPS]

Try polystyrene blocks under your tripod. It's cheap and efficient.

[Paul Ewins]

Balsa wood is supposed to be excellent for resisting vibration.

[Donald Miller]

As I understand the premise of your problem, the problem is not so much the tripod and camera shake but rather the turbine imabalance causing subject shake. In that case you will need to stop motion. The shutter speeds you mention will not do that. That calls for either more light or faster film.

[Bruce Watson]

as turbines are an vital part of this industrial process i have to devise a way to combat the vibration that they produce, infact these things create so much vibration that the buildings they are situated in are deisigned with elastic foundations, if not the structure of the rest of the plant would be damaged...

You are saying that the turbines are making so much vibration that the building they are in was separated from the other buildings just to isolate that vibration, yes? If that's true, there's not a whole lot you can do. The problem is that a huge mass is vibrating and you are standing on it.

The conventional way to deal with vibration is to increase the mass of the camera system - hang sandbags from the tripod, that sort of thing. The point of this is to make a very solid connection with something that isn't moving -- the ground. That is clearly not going to work in your case, because the "ground" is what's moving.

IMHO, your best bet is to go handheld. Either a press camera or a medium format camera. Since you don't have a lot of light, I'm thinking you'll have to go the medium format route with some big lenses that let you shoot at larger apertures and therefore higher shutter speeds.

Another alternative is to check to see if the walls are isolated from the floor. If not you don't have a lot of options. If the walls (and therefore the ceiling) is isolated from the vibration source, you might be able to hang a platform from the ceiling (that is, from the gantry crane). Swinging of the platform will be a problem but it would allow you to isolate your camera system from the vibration problem.

Just a thought...

Oh, yes. Don't forget your ear protection!

[Maris Rusis]

Is there any chance that you can bolt the camera to the building so that they vibrate together? If there is no relative movement between the two then pictures should come out sharp.

I have taken view camera portraits on a rocking boat at sea and got OK results because camera and subject shared the same movement.

[Capocheny]

Adrian,

I have to agree with Bruce W... if the entire structure is vibrating and you can't use strobes then I would use a much faster film to access faster shutter speeds.

Are you required to use LF? Or, can you get away with using a MF?

From your description... personally speaking, I think I'd use MF.

Whatever and however you decide, I hope you'll have the opportunity of doing some experimenting prior to the big grand finale. It sounds like you've got quite the challenge on your hands! :)

Good luck.

Cheers

[Brian Ellis]

John Sexton had this same problem with some of the photographs made for his "Places of Power" book. Unfortunately I can't remember for sure how he solved it. He may have waited until the turbine was down for maintenance or maybe they cut the thing off for him, I just don't remember. However, you might try sending him an email message or calling and asking. John's pretty good about responding to serious questions.

[JW Dewdney]

All these recomendations are well and good... but you have to figure out what is vibrating how first... and then figure out what to do about it. Also - depends on what you're photographing. If the turbines are vibrating independently of the building shell, then try to lock to them somehow (floor slab?) and let the rest go to heck - still using the shortest shutter speed possible. That's assuming you want to photograph the turbines.

Otherwise... I dont' suppose you can turn 'em off?Or ask when they might be down for maintenance?

[brook]

I use to work in an electron miscroscopy lab that had an an atomic force microscope that some claimed (and others disagreed) could image a single atom. The whole apparatus was situated between two big slabs of marble or granite and suspended by giant bungie cord type things in the basement lab. Even so trucks going by on a freeway a 1/4 mile away or so could still affect the results.
Something like this could be rigged with great pain and difficulty, and might even work!

[Struan Gray]

There are ways to combat this level of vibration, but a lot depends on your budget and the time you have available.

If the turbines themselves are shaking by a significant amount strobes will be the only solution. I doubt that this is the case, but you never know.

It is also possible that the flexing of the floor is giving you direct movement of the camera, either translationally, or by changing the angle of the floor. This is usually only a problem with metal plate floors or simple partitioning dividers which are quite flexible in themselves. A cast concrete raft in a normal industrial or laboratory setting will flex and bounce up and down by a distance of a few microns in the 1-100 Hz range. Really heavy plant will increase that a bit, but the biggest effect on instumentation is the extra accelleration, not so much any added vibration amplitude. If you can't see dust particles dancing on the floor, the floor will work fine as the ultimate base of your equipment.

The most likely cause is that the floor vibrations are exciting vibrations of your camera and mounting system. In this case locking everything down and attaching it to something solid, like a ring bolt in a concrete slab, is one way to go. In really noisy environments that isn't good enough, and you need to de-couple the camera from the floor motion. That's when you start to incur hassle or expense - or both.

Do you have a budget to deal with this, and are you able to erect small constructions on-site? Compact solutions using active vibration isolation are easy to use, but expensive. Cheaper, home built solutions usually take up more space.

In both cases, the approach is to take a stiff, heavy platform and couple it to the building with a very pliant support. The platform can be as simple as a concrete block, or a marble pastry slab from your local cookware shop. Or you can use a 1-ton laser table from the supplier of your choice. The support can also be simple: favourite probe microscope solutions are latex tubing from the ceiling or half-inflated bicycle tyres under the slab. Better in various ways are the various pneumatic laser table legs you can buy, and best yet for a camera are the piezoelectric active dampers which sense the motion of the floor and adjust themselves to compensate.

Your biggest problems with any cheap solution will be transporting and erecting it. Next will be the floppy nature of the support: you can change where the camera is pointing by gently touching it, or by moving the cable release about during the exposure. Setting up and focussing will also be a pain, as the camera will move every time you touch a control.

Your biggest problem with any expensive solution will be affording it. That, and getting it on-site. If you have the money, there are some nice anti-vibration workstations available for use with high-end optical microscopes which would be transportable in an estate car, and could be wheeled into place before use.

I'm happy to give you pointers and links, but it is probably best to narrow down the options first. How much do you want to spend?

[Jim Jones]

As I understand the premise of your problem, the problem is not so much the tripod and camera shake but rather the turbine imabalance causing subject shake. In that case you will need to stop motion. The shutter speeds you mention will not do that. That calls for either more light or faster film.

If the turbines have enough vibration to show in a photo, don't be anywhere near them when they self-destruct. As others say, increasing the mass of the camera and its support, and isolating that from the vibrating building is the way to go. Camera movement will be amplified if the camera and support resonate with the turbine. "Tuning" the camera and support might help. Rubber and foam can dampen vibration. I'd try foam rubber topped with perhaps plywood to support the tripod leg.

[Kirk Keyes]

Try some of this stuff - http://www.sorbothane.com/

Sorbothane is a proprietary, visco-elastic polymer. Visco-elastic means that a material exhibits
properties of both liquids (viscous solutions) and solids (elastic materials).
Sorbothane is a thermoset, polyether-based, polyurethane material.
Sorbothane combines shock absorption, good memory, vibration isolation and vibration damping
characteristics. In addition, Sorbothane is a very effective acoustic damper and absorber.

They make it for isolating precision balances and even put it in bicycle seats.

Something specifically made for (telescope) tripods that may help:
http://www.telescopes.com/products/meade-895-vibration-isolation-pads-12193.html

Kirk

[adrian tyler]

as always, thanks for all the ideas, i have just got some contacts back form the lab i made with a meduium format 38mm camera, 1 second exposures, and it seems that maris is right on the money:


Is there any chance that you can bolt the camera to the building so that they vibrate together? If there is no relative movement between the two then pictures should come out sharp.

based on this i'll try to get the shutter down and try exposing a bit longer onto plate film using some of the above advice, thanks for the tip about john sextons experience brian, i'll look that up.

thanks again

adrian

www.adriantyler.net

[Bill_1856]

How about making 10 exposures ar 1/10 sec, or 25 exposures at 1/25 sec? That's what some landscape photographers do for flowing water so it wont look like milk.

[GPS]

If you could get some interesting blare (especially if only the turbine environment is blurred and some part of the picture is sharp so as to get a point of reference) it could make for a good picture too...

[KenM]

John Sexton had this same problem with some of the photographs made for his "Places of Power" book. Unfortunately I can't remember for sure how he solved it. He may have waited until the turbine was down for maintenance or maybe they cut the thing off for him, I just don't remember. However, you might try sending him an email message or calling and asking. John's pretty good about responding to serious questions.

If I remember correctly, I think John didn't do anything - he was surprised to find that his negatives were very sharp, and he figured it was because the camera and the turbine were vibrating at the same frequency....

[Eric Woodbury]

If after testing, if this looks like it will be a problem, then some sort of isolation platform to put you tripod on would be a solution. This could be as simple as an air bladder with a piece of plywood on top and maybe some extra mass on top of that. Try some inner tubes, plywood, and sand bags. Don't put much air in the inner tubes so that they can't transmit the higher frequencies.

Another idea, a tripod on some very soft wheels.

[Michael Rosenberg]

There were many good suggestions here. I used to do microinjection of cells at 400X magnification with a cold room compressor next door, and a road 500 feet away. I could isolate the microscope by putting it on a 150lb steel platform resting on bicycle tires. But that will not help your problem because you do not want to isolate your camera from the vibration, but keep it synchronized. Putting sandbags under the legs will not work for a similar reason, they will help isolate/absorb the vibration. An analogous situation is looking in the rear view mirror of a truck while going over a bumpy road - the image will vibrating because you are not vibrating/bouncing in your seat at the same frequency as the truck.

I would recommend what others have - try to weight the tripod to keep it vibrating in the same frequency. Use a heavier tripod or hang weight off of each leg.

Good luck.

Mike

[GPS]

I have to disagree. The vibrations are not visible to the naked eye - they can only blur the picture because of the lens vibrations. Once the lens is vibrations free the subject vibrations won't blur the picture. 1/10 mm vibration on the turbine is invisible, the same amount of vibration on the lens is a different matter.

[Bill_1856]

Are you sure there's a problem? Why not try a test run and see for sure. No point in solving a problem which may not exist.

[Ben Chase]

Hmm... There are only two real possibilities in solving this problem, synchronizing the vibration or completely dampening it. Synchronizing it sounds like it would work in theory, but you would have to get as much contact with the ground as possible. To do this, I'd take the rubber feet off of the tripod and get as much metal-to-ground contact as possible. The idea here is to make your tripod part of the ground - by increasing the surface area in contact with it. I have no idea if this would work, but this is something I would certainly try myself.

As for completely dampening it out, you want something that is not going to be good at conducting vibration. Silly as it sounds (pardon the pun), I think something like Silly-Putty affixed to the bottom of your tripod legs might also be worth trying. Or in a more extreme example, Silly-Putty on the bottom of the tripod legs, with the actual legs mounted on sandbags with extremely fine dry sand (flour bags maybe even?).

This may or may not work, but it's the first things that came to my mind.

Ben C

[adrian tyler]

hi everybody, thanks again for all the great input, as i stated earlier, the medium format tests that i made at 1 second came out fine, supporting the syncronised vibration theory, john sexton has kindly replied to this enquiry in the following way:

"John indicated he did not have vibration problems as long as the
tripod was set up on concrete - not steel. He made exposures of up
to 30 minutes. The design of the buidlings with steam turbines may
be different than nuclear reactors. The camera was vibrating, but
was "synchronized" with the turbine and building - so images were
sharp."

based on this i'm going to repeat the shots, use the large format camera, on concrete and weigh down the tripod.

thanks again to everyone

adrian

www.adriantyler.net

[Struan Gray]

I'm afraid that (IMHO) synchronisation is a red herring. First, because it is extremely unlikely that the turbines are vibrating in a way that is visible on anything but a high-magnifaction macro shot. If they were, it is time to leave the building.

Second, if you do have a resonant floor, there is no guarantee that your bit of the building is vibrating in phase with the motions of the turbine. It is quite likely that your bit of the floor is going up when the turbines are going down, in which case "synchronisation" will make things worse.

LF cameras are simply not that stable, certainly not compared to the optical mounts routinely used in laboratories and pre-packaged optical instruments like a supermarket checkout scanner. The vibration of a camera is not significant for normal picture taking, but it is no surprise that for specialised applications like high-resolution aerial photography you tend to switch to a less resonant, stiffer body. The problem is not the motion of the turbines or the floor, but rather to stop the camera and tripod's own resonances from being excited by the floor accellerating up and down a few times a second. This is a known, solved problem. The only real question is how much money and effort you want to put into constructing a solution that works for you.

PS: I wrote that while Adrian was posting his reply, and it sounds a bit confrontational. Sorry. My comments are directed at the general tone of the thread, not any one post.

[GPS]

No doubt the synchro theory is a red herring. Simply because the same amount of vibrations on the turbine and on the lens gives a completely different optical result. Common sense.

[adrian tyler]

i could not believe my eyes when i examined the test roll done with 1 second exposures. the only explanation is the design of the buildings housing these giant turbines, these negs hold up to critical examination under a 10x loupe. the jpg will give you an idea of the size of the thing, incidently the fill in shots at 30th second, yes, are blurred!

[C. D. Keth]

Try this: Cut two 4x4 pieces of 3x4 inch plywood. Then face one side of each with medium shag carpet including carpet padding. Lug these to your location and lay them carpet side to carpet side and then set your tripod up on top of both.

This is what I have used to get shots for short (read: no budget) films from a moving vehicle. It noticeably steadies the shot.