Cleaning a lens vs cleaning a filter - Completely different instructions!

Discussion in 'Medium Format' started by gerard_taillefer, Aug 21, 2001.

  1. (A) Excerpt from Fujis manual for GW690 III, GSW690 III and GW670 III
    Professional cameras:

    (I quote:)

    Cleaning the lens

    As mentioned earlier, scratches on the lens surface can reduce its
    sharpness far more than you would think. If the contrast of your
    picture seems somehow insufficient and it doesn’t look crisp enough,
    the cause is usually scratches on the lens surface.

    How to clean

    (1) First, blow off dust from the lens surface completely with an air
    blower.
    (2) Next, moisten a sheet of lens cleaning paper with plenty of Fuji
    lens cleaning fluid and wipe the lens gently with it in a circular
    motion. Always start from the center, then gradually move out to the
    edges.
    (3) Finally, after all contaminants have been removed, wipe off the
    remaining lens cleaning fluid with a dry sheet of lens cleaning
    paper. Again, start from the center in a circular motion, then move
    out to the edges.

    Caution:
    Breathing a mist on the lens surface then wiping it off with silicon
    cloth or other similar material is the worst thing you can do. Never
    do it because this is one of the main causes of scratches on camera
    lenses.

    (End of quote)

    (B) Now to the ”Cleaning your filters” instructions in the Hoya
    Filter Catalog:

    (I quote:)

    Due to their high precision, filters should always be handled with
    care and kept clean whenever possible. Filters should be cleaned
    gently with just a lens tissue or soft cotton cloth, such as Hoya’s
    Hi-Tech Microfibre cleaning cloth. Never use any chemicals, such as
    lens-cleaning fluid, on your filters, as these can damage the
    coatings. If any stubborn stains occur, these can usually be washed
    off with some clean water and a soft cotton cloth.

    (End of quote)

    Now, why so completely different cleaning instructions for modern
    lenses and filters? Can anyone tell me? I am curious to know.
     
  2. Different companies, different writers, different translators from
    Japanese.
     
  3. I have lenses and filters that are decades old and well used.I always used breath vapor and a SOFT cotton cloth to cleanthem, which was not too often, and they are pristine.
     
  4. The coating is different. I've fouind the Hoyas to have very soft coating - very easy to remove and scratch (especially super multicoated). Possibly they're also attacked by chemicals.

    Fuji's electron beam coating seems harder and I haven't had it scratch (I am more careful with the lens though).
     
  5. something i've learned over the years: clean your lenses as little as possible. use filters and let them take the punishment (and collect the dust). THE most important thing to remember if you MUST clean a lens is MAKE SURE ALL PARTICLES HAVE BEEN RMOVED BEFORE YOU APPLY EVEN GENTLE PRESSURE!! i always use compressed air first, followed by a very gentle sweep with a soft cloth, followed by application of lens fluid, and finally gentle wipes to clean and dry. a single grain of grit can ruin a coating. and i recommend strongly against lens tissue paper (too abrasive) and those "micropore" cloths (also too abrasive). use a nice soft absorbent lens cloth (pentax makes/markets a great one). GO SLOWLY!!!
     
  6. I work with lenses and lens testing at Hasselbald, so I've cleaned some lenses over the years. It's actually quite difficult to do well, so I have to agree with Roger: don't clean lenses unless you have to. (Which does not mean that you could leave your lenses dirty; that does of course reduce image contrast.)
    I don't know why Hoya recommend not to use lens cleaning fluid. It seems strange that it would be possible to damage coatings chemically without extraordinary stuff, but I can't say they are wrong. I do know, however, that some filter brands are really difficult to clean. For example it can be easy to get "drying marks".
    So, blow off the dirt, and clean with a good cloth or tissue. (Some tissues are not soft enough. Kleenex is quite OK(!).)
    Be CAREFUL not to get dirt or grease from the front (or rear) cover ring (or from below the ring) onto the lens surface.
    My favourite fluid is homebrewed: A mix of ether (20%) and ethanol (hope that's the correct name). We use "spectrographically clean" ethanol at 99.5%(!). This mix dries at a nice pace and takes care of most problems, with one big exception: fingerprints. For that you have to get something like acetone into the mix. And then you really have to be careful when you get close to the plastic front cover ring!
     
  7. Supposedly the best way to clean Hoya filters withought the sratchproof coating (which is all of them except the Super HMC, I think), is GENTLY with water and a tiny bit of soap. Of course, holding your $2,000 lens under running water is not recommended. I think one thing to keep in mind here is that manufacturers are telling you how to clean their own lenses, and in most cases they developed their own coatings so coatings accross brands are not necessarily identical. They know their own lenses because that's what they've tested. So instructions for cleaning from Leitz may not be the same as from Fuji. Any by the way, watch the canned air. Even held upright and at room temp, some canned air seems to leave a bit of residue on some coatings (this happened to me using Maxel air to blow off an RZ lens).
     
  8. The only way I've found to get a Hoya Super HMC filter perfectly clean (i.e., far cleaner than needed for photographic use) is to remove the glass from the mount (yes, you risk scratching it when removing the spring ring) and clean it under running water with a bit of mild soap (as other post says), then finish the job with breath and a microfiber cloth. I dislike the microfiber cloth and wouldn't touch my lenses with it, but it works perfectly for the filters. The Hoya coating seems subject to staining, chemical damage, and even excessive "polishing" while cleaning will damage it. Lens coatings are much more durable. The Hoya coating is technically excellent and since the filter is easily replaced I think they made a good choice in using it.

    On lens tissue, there are several varieties. The very soft and almost fluffy Kodak tissue is great. There are also some flat and hard tissues that I wouldn't use. Kleenex and similar products leave residues and you can't guarantee that they are particulate free. Never liked microfiber as it tends to shed liquid and will scratch as well as anything if used dry and any abrasive particles are present. Questar ($$$) used to specify that their telescopes be cleaned with cotton balls- works well, but leaves lots of fibers. Lacking decent lens tissue, clean washed cotton t-shirt material is pretty good. Zeiss makes a good lens cleaner for fragile coatings- available from Anacortes Telescope & Wild Bird (360) 588-9000 for just a few bucks, probably easy to get elsewhere too.
     
  9. The American Cinematographer's Manual recommends fogging the lens with your breath before wiping, as the safest way to add some moisture when cleaning those super-expensive lenses on the Panavision and Arriflex cameras Hollywood uses.
     
  10. Spearhead

    Spearhead Moderator

    I ran into a guy on an Architectural Digest assignment and he was cleaning his Zeiss lenses with his shirt tail.

    I blow off the dust with a bulb blower and don't bother unless something gets on them. I haven't seen any effects at 20x24 so I'm sure not going to worry about it.

    I have seen a lot of lenses with obvious cleaning marks though...
     
  11. gerard - I imagine different manufacturers use different coatings, which require different cleaning methods to insure the integrity of their coatings. this thread, and others like them reminds me of a workshop I attended - I borrowed a filter from the photographer running the workshop - - it was filthy - - WAY more dirty than i had ever put on a lens before. I used it, and the photos taken with it were fine. I pointed out its condition to the instructor, and he didn't seem overly concerned, but did manage to clean it somewhat with his t-shirt before returning it sans case to his camera bag, all the while commenting on how paying more attention to composition and less to lens cleaning was the route to better photos.
    Prior to this experience I had been a regular lens/filter cleaner, somewhat obsessive, having the usual collection of fluids, microfibrecloths, etc.
    Now I use a clean terry cloth, my breath, and a little caution, and haven't had a problem in five years since my conversion to carelessness.
    before you next decide to clean your lens, take a flashlight and aim it down one end of your lens while looking down the other - you'll be amazed at the amount of dirt, paint chips, air bubbles, etc. that happily live in your lenses that you're probably unaware of, have no way of cleaning, and do not affect image quality.
     
  12. doubtless the architectural digest guy didn't own the gear he was using.
     
  13. The cleaning of photographic glass seems loosely linked to voodoo rituals -- everyone has his own!

    I noticed some bias against microfiber cloths, so I thought I'd jump in with my opinion. I think the bad rap comes from the way I've seen folks store these cloths; usually loose somewhere in the camera bag. Would you use a photo cleaning tissue that had dropped into the dirt? Of course not.

    I've sold hundreds of large, coarse weave, general purpose microfiber cloths. They excel at cleaning virtually anything, without chemicals or soap. Mirrors, windows, greasy stovetops, eyeglasses, chrome, buggy windshields, calculators, computers, painted surfaces, etc. I even clean my entire automobile with a 14" cloth and about a quart of water. It even removes road tar from behind the wheels!

    I use a separate (very clean) one for cleaning my camera glass. I even clean front-surface mirrors with it, and have never scratched anything. But then, I don't drop it in the dirt, and after using it a few times, I clean it with soapy water and rinse it thoroughly.

    Microfiber cloths are made of polyester and sometimes polyamide (whatever that is -- I'm no chemist). Mine are 85%/15%. Other than that, they contain no chemicals and they are very soft and absorbent.

    If a microfiber cloth scratches something, it's because you've let some abrasive foreign substance lodge in it. It probably just needs cleaning. After doing that, keep it clean and barely damp by storing it in its own little ZipLoc bag.

    More tips: Use a camel-hair brush first to knock off any gritties (so they don't get into the cloth). Make sure your hands are reasonably clean before using the cloth. DO NOT EVEN CONSIDER laying the cloth on any surface that is not totally clean! Use one side of the cloth today, the other side tomorrow, then clean and rinse it. (Hint: if your cloth has no label or other identifying mark, use a needle and thread to sew a single stitch into it, long on one side, short on the other, so you can identify which side you last used.) Microfiber cloths are not magic, but given the same care you give your body every day, a single cloth will serve you well for years.
     
  14. "take a flashlight and aim it down
    one end of your lens while looking down the other - you'll be
    amazed at the
    amount of dirt, paint chips, air bubbles, etc. that happily live in
    your lenses
    that you're probably unaware of"

    I did that to my lenses and it is a scary sight!
     
  15. I clean my lenses with and without filters the same way. I once wrecked the coating on an expensive multi-coated internal polarizing filter with cleaning paper so now I use only clean Tiger Cloths.

    http://www.kinetronics.com/cgi-local/SoftCart.100.exe/online-store/scstore/tiger.html?L+scstore+jclv4348ffd9b9d9+1182456316
     

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