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danchan
5-May-2009, 22:43
Sorry if this has been covered before. I've been visiting here for the last couple years, devouring information, and I don't remember reading about the proper way to clean lenses.

I've been really careful with my lenses and have been using a Giotto bulb blower to blast off the dust that collects on the surfaces. I purchased some lens cleaner and some lens paper from Calumet but I don't want to jump in and touch the glass on my precious lenses without knowing what I'm doing.

What is the proper method for cleaning lenses?

Also, I see a couple specks of dust inside my favorite lens, a 135mm Sironar-S. Does this affect the image quality and if so, is there anything I can do about it?

Aender Brepsom
5-May-2009, 23:47
Blowing off the dust particles first is a very good idea. After that, I use a soft Lee Filters cleaning cloth for the glass.

A few dust specks inside are a very common thing with lenses. I have never seen any problem caused by these tiny specks. You may unscrew the cells from the shutter to see if the specks are on the glass surface facing the shutter and if so, clean them off the same way you would do for the other surfaces. If they are inside the cells, just leave them there and don't bother too much.

One last thing I do after cleaning a lens is to give another blow with the Giotto rocket to chase off any fibres from the cloth that might have gotten on the glass during the cleaning process.

Lee Christopher
6-May-2009, 04:29
OOPS! Double post. Apologies.

Lee Christopher
6-May-2009, 04:29
Hi,

I'm new here but not new to photography.

I hope to contribute if I am able to.

Blowing with a bulb blower first as mentioned by Aender, is a very good idea! For me it's crucial and a default step.

Personally, I would next use a clean lens brush or clean microfiber rolled up loosely to lightly 'swish' off any remaining vivible dust particles.

Most of the time, that's all that's needed. Where cleaning is concerned, slightly too little is often better than too much.

If there are grease marks, fingerprints and the like, my next gentle step is to brush my teeth (ok, I'm advocating extra caution here; usually, I don't), then use warm breath and a clean piece of chamois. Wiping always takes place in this sequence:

breath - wipe once - inspect -breath again if necessary - a new area of chamois wipe once - inspect.

Usually, that's it. Only in the most extreme of instances do I proceed to the next step.

If the grease mark is really bad, I use clean microfiber after the blowing and brushing stage with a modified solution of isopropyl alcohol and a lens cleaner made for Swaroski optics. I suspect this solution is nothing more than untinted and non-perfumed diluted dishwashing detergent or something similar with isopropyl alcohol!

Many other methods and schools of thought exist, but the above has worked for me for over 20 years, but if anyone sees error in the above methods, please do let me know - I am willing to learn.

CHEERS!

Edited to add: The above is for external surfaces. All lenses have dust in them, and a few tiny specks is usually harmless.

hmf
6-May-2009, 04:44
Volk Optics (www.volk.com) makes cleaning wipes called "Precision Optical Lens Cleaner" designed for use on their medical optics lenses. They come individually packaged like alchohol wipes, so are easy to store in your bag/pack. I find they clean well and leave no residue.

After blowing the lens surfaces clear, I will use one wipe to clean several lenses. Discard the wipe when you're done, so cleanliness of your cloth is not an issue.

Once or twice per year is about it for any lens. A speck or two on your lens surfaces will effect image quality much less than you think, and over-handling will eventually damage the AR coatings.

seabird
6-May-2009, 06:02
Nothing wrong with any of the advice given here, but if you want to see what a respected manufacturer says, look here:

http://www.schneideroptics.com/pdfs/whitepapers/lens_cleaning.pdf

Hope this helps

Bob Salomon
6-May-2009, 06:16
Nothing wrong with any of the advice given here, but if you want to see what a respected manufacturer says, look here:

http://www.schneideroptics.com/pdfs/whitepapers/lens_cleaning.pdf

Hope this helps

Forget that I am connected to Rodenstock.

I disagree strongly with the advice above. Never use a brush first. Always use air! Don't use canned air!!! Oil less compressed air or a good quality bulb blower are the only air sources you should use.

And if you do use a brush make sure you never touch the part of the bristles with your fingers as that will deposit oil on the bristles. Lastly, if you use a brush, make sure you shake it out to remove any particles that might be trapped in the bristles. Same with a micro fiber cloth.

Windex should never be used. A good lens cleaning fluid like ROR, Kodak, Giottos would be better.

Jeffrey Arthur
7-May-2009, 10:57
I have always had good results with the lens pen. I only use the brush on it most of the time but I can usually clean the lens if it is dirty with the pen if necessary and do not have to be too concerned with cleaning marks or scratches appearing ( if I have thoroughly dusted it off). I do not like the liquid cleaners for the most part because the residue really gets out of hand. If something is really serious I have used a bit of alcohol on a Kodak cleaning tissue but that would have to be major.

bvstaples
7-May-2009, 11:19
I follow most of the advise above. Start with air. I find the Giotto Rocket Bulb a good choice for air. As for brushes, I use a camel hair brush that's devoted to my lenses: that way I'm sure it stays clean and unspoiled.

If there are other elements on the lens, then I go to the use of liquids, and I make my own. I mix a pint of distilled water with a pint of 91% isopropyl alcohol, and to this combination I add two drops of unscented Ivory dish detergent. I use the Ivory because it's the purest of the commercial soaps, and you want only detergent, no scents or other additives. It may seem ridiculous to buy a whole bottle for two drops, but in the end it's worth the couple of bucks. For a total of about four bucks I can make a quart of cleaning fluid, which will last me, well, probably the rest of my life. I keep it in a glass stoppered bottle.

To clean the lens with the liquid, I use lens tissue. I wet the tissue, then clean from center outward. Once the liquid has loosened and removed the gunk, I use dry tissues to dry the lens, again going from center outward. I apply almost no pressure when wiping the lenses, letting the agent and tissue do the work. I use this process to clean off telescopic eyepieces I use for public star parties, where mascara and other eye make-up, along with other gunk from the masses, end up on my lenses, and it works well. It works extremely well on camera lenses.

As a final step, I use a CO2 snow gun to take the last bits of dirt and lint off the lens, but these guns are expensive and one must know how to use them, otherwise they are ineffective.

BVS

Eric Woodbury
7-May-2009, 13:16
Good advice. But when I'm in a remote spot and I've got to get the pic taken or lose it, I blow off the big chunks with my mouth, steam the lens with my breath, and wipe it with my shirt tale, usually a tshirt that has been washed a 1000 times. Sounds horrible, I know.

Generally, I try not to clean lenses, just keep them clean.

rdenney
7-May-2009, 14:52
Forget that I am connected to Rodenstock.

I disagree strongly with the advice above. Never use a brush first. Always use air! Don't use canned air!!! Oil less compressed air or a good quality bulb blower are the only air sources you should use.

And if you do use a brush make sure you never touch the part of the bristles with your fingers as that will deposit oil on the bristles. Lastly, if you use a brush, make sure you shake it out to remove any particles that might be trapped in the bristles. Same with a micro fiber cloth.

Windex should never be used. A good lens cleaning fluid like ROR, Kodak, Giottos would be better.

I agree with the Schneider paper, and with Bob's amendments. That is exactly what I do. The main point worth noting in Schneider's paper is to never wipe glass with the same tissue twice.

But there is another statement in Schneider's paper I caution against, and that's cleaning often. I don't think I've cleaned my most used lenses more than a dozen times in their lives, and I've owned some of them for many decades. I would rather shoot through a bit of dust than be obsessive about cleaning. Every time you clean a lens, you run a risk. That risk should be balanced against the reward.

A bit of dust inside the lens will have no effect on the image. Don't worry about it.

Also, dust is less of a problem with a well-shaded lens.

Rick "prevention is better than the cure" Denney

Brian Ellis
10-May-2009, 08:05
What's supposed to be wrong with just blowing on the lens yourself as a first step (as opposed to using a blower), making sure there's no spittle on your lips of course? I own the Rocket blower someone else mentioned and the force of the air it puts out doesn't seem anywhere close to what I can do myself without the blower.

Bob Salomon
10-May-2009, 09:07
What's supposed to be wrong with just blowing on the lens yourself as a first step (as opposed to using a blower), making sure there's no spittle on your lips of course? I own the Rocket blower someone else mentioned and the force of the air it puts out doesn't seem anywhere close to what I can do myself without the blower.

Fortunately, the Rocket Blaster can't put moisture on the lens accidently. Blowing directly on the lens can.

Peter K
10-May-2009, 09:33
Fortunately, the Rocket Blaster can't put moisture on the lens accidently. Blowing directly on the lens can.
There is nothing wrong with "freshly distilled water" by breathing on the lens. This is a reciepe I've got from a former Carl Zeiss employee.

Merg Ross
10-May-2009, 09:52
First, be certain that your lens needs to be cleaned! A little dust on an element is not going to adversely affect the result. Just be careful with handling lenses, and use filters for protection whenever possible. I have never used anything other than air for cleaning my large format lenses; all were were purchased new, some over forty years ago, and the glass looks pristine.

However, it depends on where one photographs, and some folks may need more than just air to get the job done.

Michael Gordon
10-May-2009, 11:04
I use my mouth and my t-shirt (sometimes a microfiber cloth). Crude, yes, but my lenses are just fine. I don't partake in treating tools like museum pieces.

Best just not to clean them unless you've got serious chunks or oil smears on the elements.

Jim C.
10-May-2009, 11:48
Don't use canned air!!! Oil less compressed air or a good quality bulb blower are the only air sources you should use.



Just curious as to why you don't recommend using canned air such as Dust Off ?

Is it the risk of blowing out some of the liquid which is very cold ?

Bob Salomon
10-May-2009, 13:38
Just curious as to why you don't recommend using canned air such as Dust Off ?

Is it the risk of blowing out some of the liquid which is very cold ?

Yes, also the problems of breathing the fumes and carrying a compressed gas when you travel. Also, canned air becomes very expensive over time.

Archphoto
10-May-2009, 14:34
I use a very soft brush at times to get the dust of, even better are the anti-static ones used for old vynil records and for negatives.
I clean my lenses when ever needed and that is once a year or so.

Peter

Joe Smigiel
10-May-2009, 16:26
Astronomers recommend Collodion USP and a little embedded cheesecloth (http://www.webari.com/oldscope/atspages/techtips.htm).

;)

Peter K
10-May-2009, 22:10
Astronomers recommend Collodion USP and a little embedded cheesecloth (http://www.webari.com/oldscope/atspages/techtips.htm).

;)
... and peel off the MC-layer together with the dirt :D

Peter K

danchan
10-May-2009, 22:49
These are all great recommendations! I've been really careful with my lenses, putting in the extra effort to keep them clean in the field. The lenses are almost two years old now, and I've only ever used the bulb blower to clean them, but after coming back from a trip to China, there is dust on the lenses that just won't come off with the Giotto.

I like the idea of using some sort of microfiber cloth without solution to just very lightly "swish" off the dust. Using cleaner solution to me seems more "invasive" and potentially risky. I'll leave the lens cleaner solutions for future fingerprints and smudges. Is there a particular type/brand of microfiber cloth that works well for anyone? I just did a quick search and apparently, 3M makes a Microfiber Lens Cleaning Cloth.

Peter K
10-May-2009, 23:18
I like the idea of using some sort of microfiber cloth without solution to just very lightly "swish" off the dust.
Never wipe your lens with a dry cloth! Here (http://www.zeiss.de/c12567a8003b58b9/Contents-Frame/68749d96531e950bc12571010050d10e) you can get a lens cleaning kit. But for "normal" dirt on the lens an often washed cotton fabric like an old t-shirt and "freshly distilled water" made by breathing on the lens surface is the best.

Peter K

Doremus Scudder
11-May-2009, 05:29
The advice about minimizing cleaning is very good, and a good argument for lens caps.

However, cleaning, especially when working at the coast, etc. is often needed, and needed immediately due to the corrosive nature of salt spray, etc. This means working in the field; salt spray needs to be cleaned off quickly.

I carry a camel's hair lipstick brush, dedicated to lens cleaning and never touched with fingers, an assortment of microfiber cloths, and a small spray bottle of lens cleaner (methanol and distilled water). For clean-ups where there is no visible dust, just a bit of distilled water from the breath and wiping with the microfiber cloth is needed. When there are particulates, some careful blowing with the mouth and the lipstick brush come into play. When there are fingerprints or cloudy deposits from salt spray, the lens cleaner gets added to the mix. I keep another well-washed cotton bandana for cleaning the barrels, etc.

A word about microfiber cloths. Years ago, when they were first being introduced as lens-cleaning cloths, a sales rep came by the camera store I was working in and was trying to sell them. He maintained that they would not scratch. Being skeptical as I am, I took his sample cloth and rubbed the hell out of a Kodak gel filter, trying my best to get some visible damage. Surprisingly, there were no scratches, even after repeated attempts. That sold me, and that is what I've been using ever since. I surmise that the weave traps any particulates that may still be on the lens surface and keeps them away from the lens itself.

Best,

Doremus Scudder

Struan Gray
11-May-2009, 06:51
You can improvise a brush with a lens tissue by rolling it up and tearing the roll in half. Ordinary paper towels can also be used, but they will produce more lint - they're still better than a shirt tail.

If you don't feel like cooking up your own collodion there used to be a commercial polymer called "Opticlean" which you spray on, allow to dry and then peel off. It was being sold by Caliope in the UK (www.caliope.co.uk) but their website seems defunct right now.

There are other low-tack polymers available if you want to experiment by yourself. Dow Corning make a "Sylgard 184 Elastomer" which can be cast onto surfaces and peeled off with no residue. WARNING: I've only used this for storing and immobilising small semiconductor pieces - I would use it on one of my lenses without a second thought, but if it leaves *your* lens looking like a piece of sea glass (http://images.google.se/images?hl=sv&q=sea%20glass) don't blame me.

This kind of film is much better than any brush, but there's a startup cost or effort that puts off most photographers.

The danger of a brush or wipe, any brush or wipe, is that the dust you are trying to wipe off will scratch the lens. Where I live, a fine quartz-rich dust blows off the surrounding farmland and settles on everything. I've tried microfiber, clean-room tissues and brand spanking new brushes and all of them can trap dust and scrape it across the optical surface, leaving a scratch behind it. That said, I don't usually use the polymer casting method to clean my lenses - but I do blow them off carefully with dry nitrogen before letting any kind of brush or wipe near them.

Charlie Strack
15-May-2009, 16:34
NEVER apply lens cleaning fluid directly to the lens; always put a drop or two on the cleaning tissue, and use that to wipe the lens. If the fluid is applied to the lens, it can run down the side of the lens element, and onto the back of the element, and then dry (and leave a spot).