Wooden field camera in humid weather

Discussion in 'Large Format' started by pierre_kervella|3, Sep 5, 2002.

  1. Recently, I went for a trip to the hawaiian islands with my Ebony
    SW45 field camera (made of ebony wood). The landscapes
    were really beautiful, especially the rain forest and the volcano.

    As expected, in the heights above Kona (Big Island), the weather
    was extremely humid, and pretty warm (25-30 C degrees). In
    these conditions, after one or two days, the camera focusing
    became almost impossible with the front standard (very hard),
    while it was still fine with the rear one.

    I tried to lubricate the rail very slightly with silicon/teflon grease,
    but this did not help much. The problem was that the camera did
    not really dry up during the night. Nethertheless, I would have
    expected that ebony would react better to high humidity weather
    than other woods, but this is apparently not really true. Also, the
    SW45 is a non-folding camera, probably less sensitive to this
    effect than folding field cameras.

    So my question is the following: would you know how to prevent
    the "inflation" of wood with humidity ? Some kind of wax applied
    before going to humid regions maybe ? Putting the camera in an
    air-tight plastic bag after each exposure ? I was also thinking of
    using an air dryer, but I fear it is not very efficient...

    Thank you for your help :)
     
  2. Tough one. Wood by it's very nature loves water. It is designed to suck in water! I'm not sure how one would prevent "inflation". Wax might work, but do you want wax on your camera? (I dunno if it is an issue I don't have any cameras with exposed wood, but wax is wax and it can get ALL over the place). For overnight drying, your best bet might be a sealed bag with silca gel packs in it. They will at least suck OUT the water and you won't have to worry about heat damage from a hair dryer or anything like that. Storage in a container with silica gel should also help lessen the effects of humidity when you are using the camera (although how practical this is, I dunno).

    Personally I think that if the company didn't seal the wood, you should avoid doing so. But that is just me. I figure they know what they are doing and I'm an idiot (or so my girlfriend tells me....).
     
  3. I would contact Ebony directly, I would expect that they would give you the best answer.
     
  4. All wood swells when it absorbs moisture. Anybody that has wooden doors and windows knows this all too well. If one piece is fitted within another it can bind up and not move when it swells. <p>
    There are things that can be done to minimize the swelling problem during manufacture. First is a design that will allow for the expansion. Make the parts loose enough to begin with so that when they swell they will still move. The second is to coat or seal the wood after fabrication so that moisture penetration is minimized.<p>
    It could be that neither of these methods is possible in your case. Certainly a call to the manufacturer is in order as suggested. It just could also be that it is not suitable for use in that kind of environment.
     
  5. Hwta did they used to do to the old "Tropical" model wood field cameras?
     
  6. If any wooden camera should be able to cope with high humidity is should be an Ebony. (Considering Ebony being a very pricey camera, the camera should really be able to cope with these kinds of situations. I really wouldn't mind owning one of these gems though.) It's probably a matter of the tolerances being slighly tight, which should be easily resolved with either Ebony or the reseller.
     
  7. Pierre: I have experienced this with wood cameras other than Ebony. The cure was storing the camera in your bag with a small dessicant unit. (One of those you can recharge in the oven, aluminum frame, they cost a couple bucks from Light Impressions and many other sources.) It is more effective and the dessicant will last longer if the camera is in a plastic bag, with the dessicant. With a loose fitting bag like they give you at trade shows for pamphlets this is less of a hassle than it sounds. Put the metal dessicant unit in a cloth bag so it won't scratch the camera. This did the trick. Since the camera needs several hours to expand again after you take it out of the bag, it will be fine when you need to use it. If you won't be near an oven to recharge the thing (takes about 3 hours at 240 degrees F), then pack a few dry extras in tupperware and rotate them during the trip. (My Canham MQC seems strangely immune to this effect, for some reason.)
     
  8. I suspect the problem may be with ebony, or this particular Ebony. I am in South Florida, than which there are few places more humid, at least in summer. Certainly it is more humid here than in Hawaii, and I have been over many of the islands, including the heights above Kona. I am now on my fourth wood camera over the years, and I have never had a problem such as you describe. Not even close. None of them worked any differently from the one metal camera I had. But all of them (three different makes) have been cherrywood.
     
  9. Pierre,

    I second the motion to contact Ebony. I have an SV45U, and hike with it in East Tennessee and the Blue Ridge, and it doesn't get much more humid than here. Mornings in the dog days are almost consistently 100 percent RH and since mid-June, it's been 75-85 percent RH. I have noticed mine gets a little tight when extending the bellows for long lenses or close focusing, requiring loosening the lock knobs a little more. But it's never failed to focus smoothly after the locking knobs were loose enough.

    If you haven't checked, make sure the locking knobs don't need loosening more when it gets tight.

    Thanks!

    Steve
     
  10. Here's something that may be relevant. I saw this, written by Scott Lawson, on the Camera Review web site. It is taken from his review of the Ebony SV45U2:
    "I don't know if anyone else has done this, but I put a light coating of Minwax floor paste wax on the camera back, where the film holders are inserted. I waxed any area where the film holders contact, and I have to say that inserting and removing film holders is now almost a religous experience (OK, so maybe that's a bit of a stretch). Just make sure you don't get any wax on the focusing screen. Use the wax as instructed on the can, and buff with a cloth. I'm not sure how long the wax will actually last in use, but so far I haven't had to rewax it. If you decide to do this, use a good, hard floor paste wax (Bowling Alley or Butcher's wax would probably be best). I wouldn't wax the rest of the body, however, as it would probably make it difficult to hold onto. Ebony does recommend a light coat of linseed oil on the wood from time to time. I plan to use tung oil instead, which is a better grade of oil to use on fine wood. I think it's really used to keep the wood from drying out, and gives it a protective coating. Ebony also recommends a good leather cream for the leather bellows, to keep it supple. This is really good sense for any leather bellows."
    ...
    "I would like to make a correction. Ebony doesn't use linseed oil- they use a product made by Watco (much better than linseed oil). I'm not sure what it is exactly, but Watco does make quite a variety of fine wood preservatives and oils."
     
  11. Folks,

    While we're on the subject, Watco's oil finish is called Danish oil. They also have a rejuvenating oil for oil-finished wood (which cleans well, but doesn't leave a sheen like lemon oil, which also cleans well - they both float dirt out of the grain and remove general gom). Follow the instructions on the can. You can get it here:

    http://www.cornerhardware.com/hardware/Paint_Supplies/Wood_Finishing/Oil_Finishes_Natural-960.html

    The wax may help, try Briwax or Myland's paste wax, (or a candle) but get the product without the toluene solvent - both Briwax and Myland's make a kinder, gentler wax with mineral spirits instead. I'd fear the toluene on my Ebony.

    Thanks!

    Steve
     
  12. </i>Italics off?
     
  13. Tung oil? Tung oil?
    I dont know what the rest of you think but I would not get tung oil within 10 feet of my Gandolfi! I usually put furniture wax on my camera every six months, Keeps the wood fromm drying out too much, or getting too much moisture, keeps the original look of the camera. Tung oil will leave a shiny surface imposible to remove. I use Howard Feed 'n Wax and so far it has worked great.
     
  14. In general, I agree with the previous suggestions to contact Ebony, and at least consider their recommendations. Someone mentioned that Ebony recommended Watco's Danish Oil. That is actually an oil and varnish blend, and probably a decent choice for water vapor protection.

    I'm not an expert on wood finishes, but I researched it a bit when I was trying to decide how to finish my Bender 8x10. A good and very comprehensive book on the subject of wood finishes is "Understanding Wood Finishing, How to Select and Apply the Right Finish" by Bob Flexner, published by Rodale Press. I found my copy at the Home Depot a couple of years ago.

    Concerning tung oil, you should know that many products advertised as tung oil are actually oil/varnish blends, or what is referred to as a wiping varnish (varnish thinned with mineral spirits to wiping consistency). Some products with tung oil in the name may contain some actual oil from the Chinese tung tree, but unless the packaging on any "oil" product states that it is 100% pure tung or linseed oil, it probably isn't.

    Neither wax, pure tung oil, or pure linseed oil, will give you much protection from water or water vapor. Wax provides the least protection from water vapor, although it is an excellent anti-abrasion finish. The downside with wax is that you have to apply it much more frequently than other finishes. Many pure oil products will tend to darken the color of the wood quite a bit. They also take a long time to cure, often measured in days, and take a number of coats to achieve an even finish. Aside from the idea of using wax to ease film holder insertion and removal, wax and pure oil products aren't especially useful for use with wooden cameras.

    You could use a polymerized tung or linseed oil instead if you want more water vapor protection. These tend to produce glossy, fast drying, hard surfaces that can show cracks if you apply too thick. They are said to be expensive. I don't know that I've ever seen wood finished with this type of oil. They supposedly produce fairly thick coats, so may not be a good choice for a camera if tolerances are already pretty tight.

    For good water protection with minimal color change, consider products like Zar Wipe-on Tung Oil finish, or Hope's tung oil, etc. Many of these type products have "tung oil" in the name, but they are really just thinned varnishes. Varnishes are made by cooking oils with resins (for example, polyurethane). The varnish is thinned with mineral spirits to wiping consistency. Thinning reduces the water protective attributes somewhat over straight varnish, but makes it easy to apply in thin coats, which would be a plus for application to all the little nooks and crannies of a typical wood field camera. You can find these type finishes in satin or gloss formulations. They dry in a few hours and don't change the wood color much.

    Another option, perhaps not quite as good as a wiping varnish from a water vapor protection perspective, but still pretty similar, are oil/varnish blends like Watco's Danish Oil, Minwax Tung Oil, Behr Tung Oil, and so forth. These are similar to wiping varnishes, in that they consist mainly of thinned varnish, but they also have some straight oil added. They cure more slowly than wiping varnish because of the added oil, can be applied in very thin coats, and usually produce a soft, satin finish unless built up in several layers.

    I used Minwax Tung Oil on my Bender, and the results were very pleasing. I had to wait at least a day between each of the four coats I applied. My cherry wood Bender has a smooth and satiny feel, an elegant subdued glow, and a lovely color. On a previously finished surface, I very much doubt that you'd see any significant color change, particular on a dark colored finish like all the Ebony's that I've seen have.

    I don't think you should feel reluctant to apply a varnish type finish to the existing finish on your Ebony. It probably has a varnish finish anyway, and the varnish finishes will give you better water vapor protection than wax. Just don't overdo it.
     
  15. I bought an Ebony 45S some months ago and it gradually stiffened up over the first 3-4 weeks, to the extent that I had great difficulty in moving the standards. Application of Briwax made little difference. So I obtained a Phillips size 0 screwdriver and backed off slightly on the screws in the titanium strips which hold the standard carriers. Problem solved.

    Later on I told Matt at Robert White what I had done and he replied as follows (I hope that he doesn't mind me quoting him):

    "You did the right thing when the camera got stiff. People never believe me but this kind of adjustment can be necessary...they always want a new camera. Ebony is obviously a natural material and expands and contracts depending on the conditions...all wooden cameras do but either are built to lower tolerances or are caked in varnish to alleviate the problem. Ebony is an extremely stable wood but some adjustment is sometimes needed...a fraction of a turn is all that is needed and if you take it to the Arctic you will probably have to tighten them again."
     
  16. Matt (at Robert White) is right!! The small screws on the titanium plates/guide rails are infinitely adjustable with a small jewellers screwdriver (cross-head or Phillips) and this solves any sticking problem. I've learned that it really does pay off to carry a small tool kit in my bag! I take a lens spanner, screwdriver, tape and spare cable release!
     
  17. My other hobby is making guitars and I did some research into oil finishes a while ago. Here's my comments:-

    1) Danish oil contains Tung Oil as one of it's main components If applied properly and well wiped off after application both Tung Oil and Danish oil will give an excellent sheen rather than a shine and then high quality wax polish can be applied (again following the instructions) to achieve the required level of shine.

    2) both these oils cope well with sweaty hands and 'normal' humidity variations but not extreme variations.

    3) In the old days 'Tropical' versions of the classic wooden designs were usually made from Teak because it copes extremely well with humidity variations - they even used it for ships decks because of it's stability when exposed to sea water.

    4) Ebony and Rosewood are often used for guitar fretboards and other string instrument fingerboards. They are very stable and hard but they are porous and usually need a little lemon oil or other proprietary oils from time to time. Talking to a violin maker, he recommended Almond oil as even better for violins.

    5)I have tried Almond oil and if applied properly it leaves very little residue and is well absorbed on a violin so if it is good enough for your Stradavarius it is probably good enough for your Ebony.

    6) Applying oil finishes takes time, care and patience - on the guitars I've made I have applied Teak oil, Linseed oil, Tung Oil, Gun Stock Oil (called TruOil) and Almond oil but the key thing is to take time and do it properly - lots of elbow effort, sometimes over several weeks.

    7)If you apply oil finishes in a cold but damp winter they do not work as well as in a warm dry atmosphere - it takes even more patience to get a good result

    In conclusion, I agree the Robert White point about making minor adjustments but I think all wooden cameras (even Teak) need a little feeding from time to time especially if your travels take you from very dry to very humid.
     
  18. Thank you very much for your answers. This forum is really a
    mine of knowledge !

    Following the advice of Aaron, I contacted Ebony directly, and
    here is the answer from Ian Wilson (representative from Ebony, I
    quote him here with his permission):

    "(...) the remedy is simple: all Ebony cameras have two metal
    baseplates, one on each side of the camera bed. The wooden
    rails to which the front and back standards are attached slide
    underneath these baseplates. The baseplates are attached to
    the bed by small phillips screws, 4, 6 or 7 on each side,
    depending on the model. If the front focus knob is stiff, loosen
    the front two screws on each side (4 altogether) by a small
    amount - a few degrees is usually all that is required. Similarly, if
    the back focus knob is stiff, loosen the back four screws. On the
    other hand if the focus knobs feel a bit loose, the same screws
    need to be tightened slightly.

    In case you were wondering, by the way, all wooden cameras
    are liable to suffer from this problem, however Ebony are the
    only cameras which allow the problem to be resolved so easily.
    (...) In fact Ebony believe that the type of construction materials
    they use, together with the way they are treated and the way they
    are put together, make their cameras harder-wearing and better
    suited to changing climatic conditions than all-metal cameras."

    And about the use of silica dessicant:

    "As far as care of the camera in humid conditions is concerned,
    Ebony agrees that wiping moisture from the camera and placing
    it overnight in an airtight bag with a sachet of silica crystals is a
    good idea. Ebony also recommends rubbing the wooden parts
    of their cameras with candlewax from time to time to improve
    their water-resistance. "

    I did not know this possibility on the Ebony camera to adjust the
    pressure of the rail guides ! This changes a lot the problem...
    With this possibility, I tend to agree with Ebony that their wooden
    cameras are well suited to extreme weather, especially with a
    carbon fiber tripod (I think in particular to deep cold). I would
    certainly not exchange my Ebony for another camera ! :)

    Thanks again for your help !
     

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