Saturday, March 30, 2013


What is lens dust and should I even worry about it? Maybe. Small amounts of dust and flecks are a very common issue for all lenses. A small amount of dust will have no effect on a lens' performance. Older lenses will always have some dust.

Inspecting Lens For Dust
Looking at the front or objective element of the lens, you can typically see some dust particles in all lenses.  To check closer, remove any filters and clean the front element of the objective lens. Looking straight into the lens from the lens' front, and look for dust. Then inspect the lens holding it at a slight angle and you may see more dust behind the front glass element.

Use a LED flashlight and with the camera iris open as far as possible (smallest f number possible), shine it looking again from the front side of the lens. A darkened room will help. While changing the angle, look for more dust. You will most likely see some dust perhaps only on one element.

If you find dust, and you most likely will, there is no cause for alarm. The dust typically does not cause any problems during filming. The reason is the dust is NOT located within any areas where the dust can have any real, noticeable effects. 

How Lenses Gather Dust
How does dust get inside a lens? Every time a lens is focused in and out, it “breathes”. The physical length on the lens is slightly changed and the resulting change compresses (pushes air out) or draws (pulls air in) air into the lens. 

It is during this lens "breathing" than the lens tends to "inhale dust particles". Dust can enter the lens as most lens to not have tight seals. If lenses were completely sealed to air entry, the lens would compress the air and hinder focusing.

What To Do With Lens Dust
You have notice some dust in your lenses. What should you do? Usually the fix is to "do nothing". Don’t be concerned  about it. You can minimize dust problems by storing your lenses properly and doing routine cleaning on a regular basis. 

Can I Remove Lens Dust Myself?
Don't try to remove internal dust youself. If the dust shows on finished film you basically, have 2 options: 1) have the dust cleaned by a professional or 2) replace the lens. If you decide to have the lens cleaned by a professional, get an estimate first. The cost to clean the lens may be more than the replacement cost. 

Some people think they can "blow the dust out" with compressed air. This does not work. More likely you will drive even more dust in to the lens body. Best bet is to leave it alone unless is presents a problem and then have it either professionally cleaned or replace it.

If it is a Bolex made Switar or Yvar lens, you may be able to find somebody to clean it. Maybe not. There is more to cleaning a lens than just unscrewing a few things and dusting off the elements. Some lenses need to be re-collimated. A fancy word for realigned, and it requires expensive equipment. 

Some other lenses such as Elgeet, Wolensak and others, are designed to easily come apart to be cleaned. A warning to those who would take a chance and work on their own lenses:

Be sure if you do this yourself that you note the order of the elements and the direction (in or out) of the curved part(s) of the element. Some lens elements look flat but are actually curved slightly. If you put element in backwards,  the lens will not function correctly. 

You may leave a fingerprint on the lens element. Be sure to clean it. Fingers have both acid and oil on them and can actually etch the glass rendering the lens useless. Lens parts and screws are very, very tiny easy to loose and very difficult to find. For a lens cleaning solution, the best is made by Pancro. You can mail-order it here:


Minimizing Dust And Fungus
Shooting in relatively clean environments, properly storing your gear in a cool, dry place and take care of it by performing regular cleaning and maintenance is the best way to eliminate fungus and minimize the amount of dust that ends up on and in your gear. 

If you are in a high humidity environment, consider using anti-moisture packets. Do a Google search on "moisture absorber packets".

High moisture will contribute to fungus. Fungus typically looks like a light-ish white to dark black, wispy fine hairs in a small spot or as a black "dot". Depends on the type of fungi in the area where the lens used to live. If the fungus is on the inside of the objective lens, it can usually, but not always, be cleaned off.

If the spot is small, and/or located on the outer edge of any lens element, it typically will not show or affect the film's quality. 

It depends on the lens involved and location of the elements. Fungus left to its own devices over a long period of time can permanently damage a lens' coating. If fungus is on an element that has been coated, cleaning the fungus may remove some or all of the coating. Any doubt? Don't clean it.

Haze is a grayish appearing coating. It is formed from storage in a high temperature environment and the chemicals of the lubricant are "off-gassed" and reform onto the lens element surfaces.  Haze may look smoky or oily. Haze can be cleaned.

If a scratch is big enough to see, chances are it may show as a bright line on finished film. Unless you want the look, the lens is not usable if its on finished film. No fix - replace. Small, fine scratches near the outer edges of the front element can be ignored if they don't show in finished film. 

Very fine scratches aka, "cleaning marks" are probably not a concern. If you are buying from eBay, ask about seller's return policy and bid lower on the lens. If it films ok, you got a deal. If not, return it.

Tuesday, March 5, 2013


  • Air blower (Never canned air!)
  • Camel-hair brush
  • Lens tissue or micro-fiber cloth
  • Methyl alcohol or Ethel alcohol

The surface of most camera’s lens has a coating designed to maximize contrast, color saturation as well as minimize flare. These coatings can be scratched easily when cleaning a lens, so it’s a good idea to pay attention.

If dust is the only problem, use a camel hair brush. Avoid using pressurized canned air. Canned air can actually blow dirt INTO the lens. Use a brush first will avoid scratching the lens surface.

For smudges and fingerprints, take use  a soft micro-fiber cloth, Kimwipe, or a piece of lens tissue (folded, not bunched up), breathe onto the lens surface (never dry-clean a lens) and gently wipe the lens surface in a circular motion. Repeat if needed using a fresh piece of lens tissue or clean portion of the micro fiber cloth. 

If this doesn’t work, spray a Kimwipe with Pancro cleaning solution or try dampening the tissue or cloth with a few drops of methanol (wood alcohol) or alcohol based lens-cleaning fluid and then, very gently, wipe the lens in a circular motion.

If the lens if filthy, repeat the procedure. Do not press hard down on the lens. Let the tissue and the solution do the work. The best of all possible wet cleaning solutions, in my opinion, is "Pancro". I use Kimwipes with Pancro.

Pancro is available from several sources. All are mail-order. It is used by all of Hollywood's best Assistant Camera Operators to clean lenses. It not cheap, either. About $16 for 4 fluid ounces, plus S&H. Pancro advertises that they are the best. Their users say the same thing. Got valuable lenses? Use Pancro. You can find Pancro here:

                "Pancro Lens cleaning Fluid was judged the hands down best
                  lens cleaning solution at the Camera Assistant Olympics a few 
                  years back. It is considered the absolute best product in its field  
                  and is the first choice by most Camera Assistants world-wide. 
                  Made in USA."

Never apply alcohol or lens-cleaning fluids directly onto the lens surface. It can leak into the lens (if unsealed), wick up, and streak the objective (front) lens on the inside. Apply any wet cleaning solution to the cleaning cloth or lens paper, first. Then do the cleaning. Some people like to fold the tissue flat. I prefer to bunch it up and apply the least amount of pressure possible letting the paper and the solution do the work.

If necessary in a pinch, you can use a t-shirt or other cotton shirt or similar cotton-based material. Don't use facial tissue, paper towels, or polyester-based materials. A good photographer will always have a clean, cotton handkerchief with them for emergencies.


If their is a negligible amount of foreign contaminates on the lens and it is not going to affect film image quality and you do not have the proper cleaning gear, then consider waiting.

A few bits of dust floating between lens inner elements, or stuck to elements will have little, if any, visible impact on the sharpness levels of your photographs. Ignore it. Almost all lenses have some degree of dust internally. If you can't see it in the viewfinder; is won't be in the picture. If you see what appears to be dust in the viewfinder in a Bolex Reflex series camera, it most likely is on the reflex viewfinder and it won't show in the footage.

Monday, March 4, 2013


The procedure is called "Checking The Galvanometer Adjustment" and is in every Bolex 8mm manual except for:

            Reflex series, P1, 2 & P3, & all Bolex Super 8 cameras

Bolex 8mm "double run" 8mm camera with the letter L or LA in the model designation can be adjusted. This includes Bolex D8l, D8LA, C8L, etc.  If there is no L or LA, such as with B8 model, it means there is no metering system. This procedure is shown in all Bolex 8MM "Double run" printed camera manuals that have a light meter.

Step 1) Carefully pull out the clear plastic dial on the front of the light meter until it engages the chrome center piece. As long as you hold the dial out, the inner dial marker with the black triangle, will engage the inner dial and it can be turned.  While holding the dial out, turn the dial until the inner black triangle lines up with the outer black triangle on the outer dial.

Step 2) Holding the camera as you would for filming, note the relative position of the black meter needle and the red meter pointer. The black needle should be directly behind the red pointer. If it is, the meter is calibrated correctly.

Step 3) If the meter is not calibrated correctly, use a  small screwdriver such as a: Wiha 260 / 1,5 x 40mm screwdriver or equivalent. This screwdriver is available at

I bought mine as a set from the above link. About $27.00 + S&H. You can find the screwdrivers in sets and individually at better hardware stores.

Step 4) Insert the screwdriver tip into the hole located on the top of the meter case near the shutter plate of the left, top side of the meter. Turn screw slowly in either direction until the needle and the indicator are lined up.

Done. If you turn the screw and the needle will not turn anymore, and indicators don't line up, try the other direction. Do not force the adjustment screw when it become "tight". It the meter cannot be adjusted correctly, either the selenium cell or the meter is bad. There are no internal adjustments in these cameras. In this case, both the meter and cell will have to be replaced as a "matched pair" from a donor camera.

All the meters are the same within the same series of cameras. D8L meters will fit a B8L camera as it is the same series. Later series of Bolex D8LA meters will fit C8LA, etc. LA series meters will not fit non-LA cameras. If you have a LA series camera, you will use a LA series camera as a donor. If you have a bad selenium cell or meter (needle), you will need to change BOTH as a matched pair. This is delicate work. New meters are not available. You'll need to buy a donor camera. Be sure the meter works.

Remember, the meter is designed for 25 and 40 ASA. Your will NOT find theses ASA speeds for sale anywhere. Typically you'll find ASA 100, 200 or 400. Maybe B&W film at a higher than 400 ASA. You will need to close the iris or use a neutral filter if the shutter control can't cover the difference in the calculated exposure index.

An external meter such as a Sekonic L-398 is recommended. See blog on metering with Ektachrome here: