Tripod for Hasselblad

[ray .]

This has turned into a real nice discussion on the physics of stabilizing a camera. I love to read this

stuff.

 

My thinking is that I probably wouldn't need more than a few seconds of exposure, maybe more, or

whatever would be required in a city scene at night. ISO possibly being as slow as 100, maybe more

commonly 400. The grounding would probably in most cases be asphalt or concrete, or sometimes

something like dirt or grass.

[zack_zoll]

<p>Good analogy with musical instruments, Q.G. I'm a guitarist myself, and I can tell you that one of the best-known electric guitars for sustain is the Gibson Les Paul. The Paul has a solid maple top, which is a VERY dense wood. That top allows the strings to resonate for a VERY long time, since you're effectively 'moving' more of the guitar. The back part of the guitar is mahogany; it's much lighter, and doesn't affect the sound as much since it isn't on the string side. I also own a Les Paul where the top is also mahogany. It sustains much less, since you're 'moving' the guitar less every time you play a note.</p>

<p>BUT! When I refinished it, I used a much thinner coating of lacquer, and now it sustains longer than it did before. Why? Lacquer is harder and stiffer than wood - that's why it's used as a protective coat. The extra stiffness prevents the guitar top from resonating, meaning that it has less energy to 'feed back' to to the strings. So if you had a maple-topped Les Paul with a fixed bridge, and you didn't finish it at all, it would sustain longer than anything else out there. The only reason that they <em>don't</em> do this is that not finishing a guitar makes it extremely prone to damage, and all your sweat will collect in the wood and make it really ugly after just a month or two.</p>

<p>Okay, now to bring it back to tripods :)</p>

<p>First off, heavier is better. Newton's first law of motion: objects at rest tend to stay at rest. If the tripod has more mass, then it will take more vibrations/wind/etc. to make it move. It will probably vibrate more when it does move, but if the wind is bad enough to shake a heavy, stable object with relatively little surface area, then you should probably be inside anyway.</p>

<p><em>Stiffness</em> is a double-edged sword. A stiffer tripod is less likely to move. But when it <em>does</em> move, it will move more. If you have an ultra-stiff tripod, you basically have the camera set on the ground. Any vibration from the ground will go right up into the camera. If you're walking around while the shutter is open, a stiff tripod will be more likely to cause camera movement. If your camera causes vibrations (mirror slap, etc.), the tripod will not absorb those.</p>

<p>As for rubber feet vs. spikes, let me give you another music analogy. Many high-end speakers come with (or are sold alongside) hard metal spiked feet that sit on top of hard plastic discs. The purpose of this is to isolate the speaker from the floor; any vibrations (sounds) that the speaker produces stay in the speaker cabinet, rather than getting transferred to the floor. Aficionados claim this makes the speakers sound better.</p>

<p>If a speaker <em>wants</em> to vibrate, and your oblige it by putting spiky feet on it, then one would assume that since the camera doesn't want to vibrate, the best thing to do would be to use rubber feet. A lot of tripods have rubber feet that screw down to expose spiky feet. This is really useful if you're using the tripod somewhere soft, like on dirt of a carpet. But if you're on a hard surface, or if you have to pick one, you're better off with rubber feet.</p>

[Ed_Ingold]

<p>If the surface is even moderately unyielding, like a sidewalk or even wooden floor, vibrations generated by the camera would have to shake enough to make a perfectly rigid tripod skip into the air.</p>

<p>Of course, nothing is perfectly rigid, but there are various degrees. A good, if subjective, comparison is to attach a long lens and tap a leg about 1/3rd down from the top and observe the magnitude of vibrations through the viewfinder, and how rapidly they dampen with time. Try this on several tripods, on a show room floor for example.</p>

<p>With Hasselblad, vibration from the flapping mirror, or even a focal plane shutter is enough to take the edge off of many photos, expecially in the critical 1 to 1/15 second range. Shooting digital with an Hasselbad can be an humbling experience until you polish your technique.</p>

<p>Rubber leg tips are usually pretty firm. The only springy one's I've encountered are the bulbous rubber caps used to cover the spikes on some aluminum Gitzo tripods. There was much more flex in the legs themselves than in the rubber tips.</p>

<p>Newton wrote three laws. In this case it is the second that applies. A body will accelerate on application of force inversely proportional to its mass. More mass means less displacement, but it will still move.</p>

[q.g._de_bakker]

Tim<br><br>Rubber feet do help. Everything that moves a little bit when pushed helps dissipate the energy. May sound a bit counter-intuitive, but allowing 'micro-movement' in many places will help reduce bigger movement in the place we would like to see no movement at all.<br><br><br>Zack,<br><br>To get this clear: a more resonant guitar will lead to less sustain. If lacquer (applied to seal the wood against its biggest enemy: moisture) makes it more rigid (which depending on what type of lacquer is used it could a bit, or a bit more.) It is exactly the stiffness of the lacquer layer that would perhaps help get more sustain, with the energy of the string having no place to go. So if there is a difference, an unfinished maple top will give you less sustain than a finished top. So if a fan of sustain, you did good applying lacquer to your Les Paul. (You didn't refinish an oldy, i hope? To refinish an 'unburst' Standard would be a crime! ;-) )<br>The bridge (and the tailpiece) of a Les Paul is anchored in the mahogany body, and it's not just the top that plays a role.<br>With stringed musical instruments we generally want the wood to resonate. It will have a great effect on the tone an instrument produces (so - on a side track - people looking to buy a Les Paul or other electric guitar: play it unplugged first, try different ones and find the one that sounds best unamplified already. No two pieces of wood are alike, and there will be a difference, no matter that they are all the same model costing the same money.) It does that in (small) part by that "feed back" to the strings you mention, altering how they vibrate. But that does reduce (!) sustain.<br><br><br>Edward,<br><br>Your assertion was that when rigid enough, we would not need mass. A rigid, mass-less tripod would readily jump up in the air even when you drop a small coin on the floor next to it. Unless, that floor has so much mass that it is left umoved by the impact of that coin. Wind, or any other force applied in any way to a perfectly rigid but mass-less tripod will make it move without much effort. Unless that perfectly rigid, but mass-less tripod is rigidly attached to something else. If that something else is perfectly rigid, but mass-less, it will make no difference at all. And so on, until you find a thing to tie the whole to that does have enough mass.<br><i>"A body"</i>, you write, <i>"will accelerate on application of force inversely proportional to its mass."</i> Rigidity is what turns a loose assembly of bodies into <i>"A [single] body"</i>. Fix that body to another rigid body, and do that very rigidly, and the result will again be <i>"A [single] body"</i>. Etc. The <i>"will accelerate on application of force inversely proportional to its mass"</i> part is the thing to worry about. It's mass that is the main working part of a tripod.<br><br><i>"More mass means less displacement, but it will still move."</i> is correct. So we need those little helpers that each move a little bit. Hard rubber tips are not as inflexible as metal ones, so absorb a bit more energy by flexing a tiny bit. Softer rubber tips do a bit more. Etc. Until (if we continue on this track) we have a tripod made of highly flexible material, that isn't evenable to stand up (literally) against the force of gravity. Then we would have wanted something that's a bit more rigid. ;-)

[zack_zoll]

<p>Q.G.<br>

I have some doubts about what you say about musical instruments. This is a tangent, so feel free to respond via PM is you think we're too off-track.</p>

<p>A more resonant guitar <em>may</em> lead to less sustain. It generally does, but this is because a more resonant guitar generally has less mass, and all parts are anchored less solidly to the guitar. This makes it a chicken-or-the-egg question. For instance, Gibson's ES100 series are hollowbodied electrics, and their ES300 series are hollowbodied electrics with a center block that the guitar's bridge is bolted to. The 300 series has more sustain ... but is this because the center block reduces resonance, or because the block gives the bridge something more solid to anchor to?</p>

<p>I can only use my refinished guitar as an example. When it had heavy lacquer, it sustained less than when it had light lacquer. It did also weigh a lot less after the refinish though, and I can't tell you what proportion of weight lost was due to lacquer, and what was due to the belly carve and sculpted heel that I put on it.</p>

<p>Most high-end guitars use lacquer, as it is softer than polyurethane, and settles into the wood after a few years. Fender (and others) use poly, since it is so much more durable. Fender also uses harder woods than Gibson and their instruments are lighter, but I can tell you that a maple-topped Les Paul will sustain longer than a Maple Fender Stratocaster with a solid tailpiece ... at least, it sustains longer than the one maple Strat I've used. It's not exactly a common version of the Strat, so I can't say I've played a lot of them :)</p>

<p>And no, I didn't refinish an expensive Les Paul :) I've had a green Double Cutaway Paul for about ten years now, and a couple years back I decided to put Burstbucker pickups into it. They go for about $300 a set. I had someone offer me a faded Les Paul mahogany for $450, which had those exact pickups in it already. It seemed like a no-brainer :) So I bought the Faded, put the pickups into the Double Cutaway, put the old pickups into the Faded, and then said 'what the hell?' and refinished the Faded. I figured it wasn't going to look any uglier than when I got it.</p>

<p>It's much more comfortable to play, so the Double Cutaway has been in the case for a year or two now. I thought about selling it since I'm not really using it, but it was a special edition, and it's really not replaceable. Since the only way I could obtain another one would be by going to the Gibson Custom Shop and paying them what I would pay for a decent used car, I decided to just keep it.</p>

<p>After doing a slight resculpt on the body, I applied the lacquer French style, rubbing it into the body, rather than spraying it on. It was a lot more work, and it's not nearly as protective (since the lacquer is <em>in</em> the wood, and not<em> on</em> the wood), but it does ring much truer.</p>

<p>Mass and stiffness both play a part. But they fight each other. For starters, very few things with a lot of mass and density are very stiff. The densest (common) elements on the periodic table are mostly soft metals. So you need to pick one. If you compare two guitars with a lot of mass, one stiffer than the other, the less stiff guitar will sustain more, but not on every note. If you play hard enough for the body to vibrate, it will 'feed back' to the strings, assuming everything is solidly anchored. The vibration of the body causes the strings to continue to vibrate as well. If you play lightly, a stiffer guitar will absorb less vibration, causing the strings to sustain longer. Then there's the matter of your hand absorbing vibration ... in both cases you, the player, are reducing sustain by holding down the strings on the guitar. A more resonant guitar will 'fight' this by introducing its own vibrations, while a stiffer guitar will not.</p>

<p>Going back to tripods. Finally :)</p>

<p>A stiffer tripod will be much more likely to show movement from small vibrations, such as mirror slap, or people walking by. But a larger vibration (say, if an 18 wheeler drives past) will cause some movement, and then stop. A less stiff tripod will continue to vibrate longer after the truck passes by. But in the case of tripods, this is easily avoided by paying attention to what is going on around you.</p>

<p>I got no way to connect 'holding the strings' to 'using a tripod', sorry. You probably shouldn't be touching your tripod while the shutter is open :P</p>

[q.g._de_bakker]

<i>"[...] but is this because the center block reduces resonance, or because the block gives the bridge something more solid to anchor to?"</i><br><br>The solid block will be less likely to resonate than a thing arch-top table. More inert. So less energy will be transferred from the strings to the guitar, hence longer sustain.<br>The bridge and tailpiece are fixed about equally well to both that block and a thin table. There is no play to speak off, not a matter of a loose bridge taking energy away by rattling. It still is easier, of course, to break a bidge out of a thin table than out of a solid body/centre block. The difference will thus be down to the 'give' in the material, which is less in such a solid block of wood.<br>So both/it's one and the same.<br><br>Though interesting (i like to tinker with guitars myself, am looking at a number of instruments in various states of construction right now - we all need hobbies, don't we?) i agree we should turn this back onto tripods.<br>Les Pauls, about the heaviest solid bodies, do indeed have a longer sustain than fixed bridge Strats, despite the bulk of the wood they are made of (mahogany) is indeed soft. The hard maple cap will help. But being heavy does most of it (some argue the set neck helps too, but i'm not sure it does). The much lighter SG, also mahogany, has a noticeably shorter sustain.<br>Equally, a massive tripod will reflect most of the vibrations that originate in the camera that's fixed on top of it back into the camera. A small mirror weighing something in the region meassured in tens of grams, flapping up violently is not going to shake a 5 kg tripod.<br>And that's both good (mostly) and bad. Good, because that same tripod will be equally unimpressed by anything that it is standing on, or might be pushing against it as long as the differences in mass, or force to mass relation is the same. The more mass a tripod hass, the harder it is to shake. That's the good bit: mass <i>is</i> the main working part of tripods.<br>The bad thing is that about sustain. The energy released inside the camera and shaking it will have no place to go, unless we give it some place to go.<br>Fluid heads are very good in absorbing that unwanted energy. Regular heads are no way near as good, but can be better as they are if we don't tighten every screw as tight as we can. A set friction ball head is better than one that has to be, and thus is, locked down tight. Just as (back to guitars... sorry!) a tremolo bridge is bad for sustain.<br><br>And now we're back on guitars... ;-) stiffer guitars will always have longer sustain. Feed back of vibrations into a string = energy first taken away from the string = dampening = shorter sustain. If all of that energy would be fed back into the string, there would be no loss. But there is no world in which there will be no loss. So the more resonant/less stiff the guitar, i.e. the more energy is dissipated into parts of the guitar other than the strings, the shorter (!) the sustain.<br>(Not on every note, because as you know the resonant properties of the guitar body are - despite, in accoustic guitars at least, much effort is put into making an instrument that 'sings' at all frequencies/notes - not the same across the scale.)<br>But we would not want a guitar that has infinite sustain. It's timbre would be terrible, i think.<br><br>The hand on the bridge of a guitar (bad playing position anyway, i think, both because it will slightly detune the guitar and - more improtatly - you get a richer tone picking nearer the neck), absorbing energy, is not a signal to the guitar to start fighting that. Whether a guitar is more, or less resonant, putting your hand there has only one result: it just dampens the string, taking away the high frequencies first.<br>There is an equivalent, a way to connect the hand on the bridge to using a tripod: it's holding your hand on the camera. It will indeed help a lot in reducing vibrations, again the higher frequency ones most. But you must be careful indeed not to be the cause of extra vibrations. Yet it does indeed work, for the same reason you shouldn't (unless you are after that effect, of course) put the hand on the bridge or fret too loosely.<br><br>In short: stiffness in tripods is necessary to keep the thing up, but apart from that only helps transmit vibrations undampened. We could do with a bit less of that.<br>Mass reduces the chance that external vibrations are passed on to the thing on top of the tripod. But it does the same to vibrations that originate in the thingy on top of it.<br>Less stifness helps reduce that latter thingy, while it also helps reduce the transmission of external vibrations.<br>Flexibility and stiffness combined will lead to resonance. Which is good because it takes away energy, but bad when it feeds that energy back into/channels it to the thing we want to hold still. We do not want tripods to 'sing', don't want them to be like the tone bars of a vibraphone, but as floppy/sloppy as they can be while still holding the stuff we put on them.<br>And/but most of all we want them to be massive. They must have lots of mass. Really lots of it.

[Rob F.]

<p>LFI (some of you may remember it as <em>Leica Fotografie International)</em> published the results of an experiment in which various shake tests were done on heavy tripods light ones, carbon ones, and non-carbon. They used a light beam projected from the tripod to a wall target to register how well or poorly the tripod coped with floor shock and shutter-button presses. They also simulated wind effects by hanging a swinging weight under the tripods.They concluded that while a carbon tripod was better than a metal one of equal weight, a heavier metal tripod could outperform a lighter carbon fiber one.</p>

<p>It's the January 2006 (1/2006) issue of LFI. The author is Kai Hamann. " . . . we noted the total horizontal and vertical oscillation in arc-seconds (1 degree = 60 arc minutes = 3600 arc seconds)." (p. 28.) They reported that the Berlebach Report 2022 (ash wood, 2.9 kg.) had the least oscillation at 1760 arc-seconds.</p>

<p>Next was the Giottos MT 8170, Carbon-fibre, 2.6kg., with 1910 arc-seconds. The Manfrotto 055 ProB, aluminum, 2.6kg., measured 2290. Manfrotto 055MF3 Mag Fiber, (carbon Fiber) 1.9Kg., came in at 2550. Gitzo G1257LVL, Carbon Fibre, 1.6kg., measured 3080 arc-seconds.</p>

<p>So, where the tripods were equal weight, eg. the Giottos MT 8170 and Manfrotto 055 ProB, carbon fiber was better. The Manfrotto 055MF3 And the Gitzo G1257LVL were both carbon fiber, and the heavier Manfrotto won. </p>

<p>The heavy wooden Berlebach beat them all. And the mid-weight Berlebach Report 8023 (ash) edged out the Giottos MT 9160 (aluminum), 2020 to 2050, though both weighed 2.7kg. So it seems that the material counts most when both tripods are of equal weight.</p>

<p>That would seem to be consistent with higher mass being important for reducing vibration (all other things being equal). It is what I believe. If I want the highest image quality, I use my Manfrotto 3221 in preference to the lighter 3001, or my even lighter Gitzo. I also will use the 3221 for the Hasselblad, and the D700, in the belief that a heavy tripod makes sense with a heavy camera. I'm more likely to use the 3001 or the Gitzo with a Nikon FE2 or a Leica M6. I think it makes sense to avoid top-heaviness by using a lighter camera and a smaller ball head with lighter tripods. Something about a heavy weight atop a light support suggests instability.</p>

<p> </p>

[Rob F.]

<p>A similar argument goes on among audiophiles. Some believe that a vinyl record should be supported on a resilient mat, like rubber; while others feel the mat should be more rigid. I used to work as a technician in an audio store that made turntable mats out of glass! The idea was to transmit the vibration to a solid, high-mass substrate, rather than letting them bounce around in the vinyl.</p>

<p>Wife is calling. More later . . .</p>

[fotografz]

<p>Here is an interesting little tripod stability test to try if you have a digital camera, or digital back.</p>

<p>For many years I shot sequential stop action still photos that were then animated on a motion editing machine. These had to be pin-registered perfectly matching backgrounds with only the actors with-in the scene moving frame-to-frame. The finished product was used for test TV commercials before the full blown one was shot for real.</p>

<p>Each still frame was layered on top of the previous shot in Photoshop, where you could turn each layer on and off to see the action sequence, and to also make sure there was no movement in the inanimate part of the scene. We found out quite quickly that a locked down tripod with a lot of mass had to be used. We finally ended up with a Gitzo G500 and a massive Manfrotto Proball 469. </p>

<p> </p>

[Rob F.]

<p>Getting back to what I was going to say about this topic within the audio realm. The current thinking is to rigidly ground items like speakers, CD players, and even amplifiers, rather than to place them on a shock absorbing medium, such as a foam pad, or the like. One buys conical shaped metal feet (one brand is called "tiptoes") to place underneath these components. Placed under speakers, the pointed tip penetrates the carpet to make connection with the wood or concrete floor. Under a CD player, the tiptoes are thought to improve sound quality by making a more solid connection to the shelf underneath. Then there's the Blu-Tac crowd, who stick their speakers down to their stands with sticky stuff that is resilient rather than sticky.</p>

<p>Record turntables are another matter. Most have the platter, motor, and tonearm on springs, to isolate from room vibration that might cause feedback. That's a bit like having rubber feet on a tripod. When it comes to what to put the whole turntable on, there are two distinct camps. Me, I put the turntable unit on a marble slab, which sets on a heavy particle board cabinet, which in turn sits on a carpet over the concrete basement floor. That conforms to the "let's make it nice and rigid" theory.</p>

<p>Enter an English turntable, Linn Sondek. Their platter is suspended on springs, just like practically everyone else's. But then they want you place the turntable unit on a "flimsy" (I'm pretty sure that's the word they use: "flimsy") table--not on a nice strong solid one. I dunno why, but it sounds like Q.G.'s ideal tripod--perhaps the flimsy table absorbs vibration, iin a similar way. Come to think of it, I wonder why Linn doesn't sell its own high-priced flimsy table--a missed opportunity, as they do get top dollar for their stuff. Well, maybe they do have one.</p>

<p>Not sure what my point is, other than that audiophiles are fond of these debates, even more so than photographers!</p>

[david_smith35]

<p>Using mirror lock up and a cable release will contribute more to a sharp image than worrying about how heavy your tripod is.</p>

[paul_loveteck]

<p>I support David: mirror lock-up, cable release are way more important than weight of the tripod.<br>

Then, unfortunately, there is a point most people and most studies forget: what is important is how much the camera vibrates DURING THE TIME the shutter is open. The amount of vibration before and after is irrelevant to the quality of your picture.<br>

Some tripods will be very good for short exposures (1/125s for example) and poor for long exposures. A light tripod transmitting efficiently the initial vibration to the ground will be much better than a heavy monster at 1/250s. If you pause 10 seconds, it's a very different story.<br>

Regarding turntables, I was part of a small team which "discovered" by accident that a turntable which was resting on three nails (we did not have anything else at hand) produced amazingly clean sounds. After a year or two of experimenting, that became the cones most high end tables and other hi-fi equipment have been using since! The turntable became the Goldmund (for those who know). Although the complete math study has never been done, it seems that a sharp point like contact with the "ground" is the best way to dissipate micro-vibrations from the environment to the ground.<br>

One of my projects has been to mount my tripod on nails and see how well (or bad) it would do. (Of course, on solid ground as nails on sand would not do any good!). So far, I never found the time to try and my Hasselblad's have not been nailed. . .</p>