Cleaning Objective Dust (1 Viewer)

[eronald]

So I carry my Ultravid HD with no objective covers under my jacket every day.
I have a raincatcher, so the oculars stay fairly clean.

Unsurprisingly, dust accumulates on the objectives.

I just want to get rid of the dust - not clean the lenses.

Advice?

PS. I know how to *clean* my lenses. This is a case of *not* wanting to use that process. I want to do as little as possible.


Edmund

 

[nkbj]

I use the same rubber blower ball as I use for blowing dust of camera lenses and sensor. Try searching for "rocket blower".

 

[Troubador]

I use a soft brush and gently apply the tips of the bristles to the lens in a sweeping motion with the bino angled down towards the floor so there is a good chance dislodged particles just fall away. Dislodged dust and other particles are sometimes removed from the objective but instead of falling away they land on the inside of the objective barrel, between the lens and the rim of the opening, so I always take care to flick this area with the brush as the last thing I do to ensure all of the particles are removed. A rubber blower can certainly help but some particles seem to stick to the coating and need dislodging with a brush any way. Probably a mix of these two techniques is a good idea.

Lee

 

[yarrellii]

Funny stupid thing that happened to me using a soft brush (I share it so that it does not happen to any other forum members).

So I had this little soft brush to get rid of the bigger dust/debris particles before (or sometimes instead of, as the OP intends) actually cleaning the objective lenses. Everything went well until a certain moment where I started to notice that the glass would get worse after tinkering with the brush. It turned out that, without noticing it, once I had used the brush while the objective had a little droplet of a greasy substance, and from that point on, the moment I used the brush, I simply covered the poor glass with a thin layer of grease. Lovely, innit?
Lesson learned.

 

[Apochromat]

The Clean Binocular

Short answer:
Get a GIOTTOS Rocket Dust Blower Size AA1900 (any other China- made dust blower, such as used in some cleaning kits is useless). Blow it off.

Long answer:
Optical companies know that most customers (e.g hunters) are not willed or able to properly clean a binocular/ spotting scope or any other product. So some offer little things/gizmos (e.g. cloths, blowers, brushes) to allow for easy "cleaning" that is better than using a piece of rough kitchen paper. Or the tip of the tie. As demonstrated here: https://www.youtube.com/watch?v=yii7G3p5Sic (at 1:58).

Also, it is easy to over"clean"a bin etc. by affecting the outer hard coated anti-reflex-layers of optical surfaces with those microfiber cleaning cloths supplied also by the big three names. They are dangerous IMHO or make it even worse than before. Why? Because a normal/ untrained person usually applies way too much pressure on the lens surfaces also when using the cloth.

The cleaning depends on whether the lens surface is treated with a Lotus-effect-layer such as LOTUTEC, SWAROCLEAN or AQUADURA or not, like on an older ZEISS DIALYT 10x40 T*P B GA.

Assume that we are cleaning such a treated outer lens surface:
If we are just talking about some dust particles (sand grains, pollen, skin particles, soil particles etc.) the traditional way is to use that famous soft brush. I am always warning to use the brush/ I am against it totally, as it will often apply oily/ greasy residues from former "cleanings" onto the lens surface. At worst it can scratch the lens surface too. Just blow the loose particles off with the LARGE GIOTTOS AA 1900 dust blower. Also a few and occasional rain drops will disappear now.

If some small residues from liquids (e.g. evaporated water droplets) are on the objective or eyepiece surface and as such that they will disturb the image quality the method I use is as follows:

First we have to make our own cotton swap cleaners: Get a wooden stick. Bamboo sticks (as used for barbecue), elder wood sticks (available from handicraft work retail shops; they can be pointed with an unused pencil sharpener). Have a small volume of tap water aside. Use KERMA OPHTALMOLOGICAL COTTON WOOL only (PZN-04751039, see here: https://kerma.de/wp-content/uploads/2016/10/Augenwatte.pdf). Wet the tip of the wooden stick so that the cotton fibers will attach more easily. Form a cotton swap as shown here: https://applications.zeiss.com/C125792900358A3F/0/3C1DAE76330E42F7C12579EC0028F56B/$FILE/50-1-0025_the_clean_microscope_e.pdf). Apply a very generous amount of cotton stepwise on the wooden stick. Make sure that the wooden tip of the stick is safely and fully covered by generous amounts of cotton fibers. Otherwise the lens will get scratched easily.

Q-Tips or readily made up cotton swaps for medical purposes are not recommended (treated with chemicals or having the wrong cotton fiber length for optical cleaning, too little amounts of cotton etc.). The expensive microfiber cleaning tools from e.g. TEXWIPE (albeit resulting in perfect cleaning results in the right hands) are also not suitable here as most people will apply too much force with them. Over long periods of time that will also affect the coatings. Bins have a long use time (20-30 years or longer).

Now VERY CAREFULLY ONLY (!!!) breathe on the glass surface. As a result you have a very even thin film of distilled water produced on the glass surface. Without any pressure (!!!) make circular movements with the cotton stick from center outwards on the lens surface. Replace the cotton and repeat a few times. It also helps to grip the bin with the other hand and rotate it during the cleaning movement slightly.

The inspection of the lens surface with an office desk lamp will tell you when the cleaning was to your like. Also the cleaning I do under such a lamp illumination.

Residues of finger prints are first removed with diluted dish washing liquid (1 drop, e.g. PRIL, FAIRY ULTRA (only the clear versions of such liquids) in 50 ml of warm tap water).

Residues of more greasy contamination have to be removed with organic liquids or sometimes strong organic solvents, but this would be another topic to talk about.

If the image looks good, don´t clean too much!

A strong and direct LED illumination into the optics will always reveal some small internal dust, coating imperfections or tiny air bubbles melted into the often very expensive glass material in bins and spotting scopes, which are unavoidable and do not affect image quality at all (except on optical planes conjugated to the image plane) if small in size and number.

"Optics are made to look through them, not at them", Ernst Abbe already said.

All the best
Michael

 

[Binastro]

Flicking a soft brush only transfers finger grease onto the brush, which over a short period will transfer to the lens being cleaned.

I use a high quality Swiss bulb with a two way valve. This is used by watchmakers

The Giotto Rocket blower mentioned above is also good, but many camera stores don't stock this, and sell lower quality high profit margin bulbs.

The main thing to have in mind is that grit scratches, so minimum force is needed and a careful look with a loupe unless one is short sighted and can see tiny detail.

I also use Kleenex white large tissue, making repeated corners that are only used once and then the tissue thrown away, using several tissues. Almost no force is used. Just pick up one piece of dust at a time.

Some of the old large lenses I have successfully cleaned were caked in years of grease, dirt and dust to a thick layer. I doubt that many or any binoculars are ever this bad.
The grease actually provided a protective layer and eventually the glass came up pristine. But these were usually uncoated lens from before 1950. The glass used then was simple and very tough.

Front objective elements of binoculars are usually inert hard glass, but rear eyepiece elements are sometimes soft. The coating on them is probably harder than the glass. But if this coating is scratched by careless users, or users who just don't care or don't know anything about optics, then there are problems. The rear eyepiece element can quickly become useless. Probably £100 plus to replace each rear eyepiece element if stocks are available. Often the binocular is a write off. There are also few top class repairers nowadays.

Impatience and too much force will lead to damaged optics. Sufficient time and minimum force are needed.
With grease it can be a problem. I use Baader Optical Wonder fluid, but this isn't available in the U.S.A. or Canada.
Sometimes the Baader fluid doesn't seem to work, but the next day the remaining grease seems to have evaporated.

B.

 

[Apochromat]

Giottos

The GIOTTOS air blower rocket is available from AMAZON worldwide. In Europe its around 15 - 20 EUR. In the US it is about the same (17 USD).

Solvents: "Wonder fluids" often make me wonder. And the supplier happy.

For non-Lotus-effect coatings (e.g. older ZEISS Dialyt bins):
To remove grease, oils etc. a mixture of spectroscopic grade 85% iso- Propanol with 15% super clean n- hexane works as well as ultra- pure ethanol. Also spectroscopic grade acetone is excellent, but I have no wish to test on my own bins whether the rubber or polymers used will be dissolved by the contact with it or not. Some of the Lotus-effect coatings do nevertheless not like solvents and these should therefore only be used when a real accident, e.g. contact with sticky resins from conifers, occurred.

For LOTUTEC, SWAROCLEAN, AQUADUR:
What is also excellent for grease removal (but its slight residues must afterwards be removed with the aqueous cleaning method I described in my first answer) are the CARL ZEISS sealed cleaner wipes for eyeglass cleaning/ general use in cleaning optical surfaces. They stay as they are for long periods of time and are also available easily and everywhere in Europe and the US/ Canada. They are inexpensive and come in a nice box, 30 pieces each. They will not affect the Lotus-effect coatings.

Thanks
Michael

 

[eronald]

Hi All,

Thank you very much for these helpful replies. Let me clarify again, I just want to remove dust that accumulates every day on the objectives. After a couple of days unprotected, the objectives are literally covered. I don't want the lenses sparkling - I know how to do that, and I want to not do it, I want the daily dust to get lost specifically from the objectives.

I've washed the dust off - lightly soapy water, finger - and that seems no-risk, but my experiences in the past with photo lenses are that brushes accumulate dirt and are themselves abrasive, and a big bulb can turn into a sandblaster and actually damage a lens.

I'm not being finicky about clean lenses, I want the dust gone, not a totally clean lens. I want to avoid damage. Do this daily for a few years and I will have repeated the process a thousand times, that's a lot of cycles.


Edmund

 

[Apochromat]

Hi All,

Thank you very much for these helpful replies. Let me clarify again, I just want to remove dust that accumulates every day on the objectives. After a couple of days unprotected, the objectives are literally covered. I don't want the lenses sparkling - I know how to do that, and I want to not do it, I want the daily dust to get lost specifically from the objectives.

I've washed the dust off - lightly soapy water, finger - and that seems no-risk, but my experiences in the past with photo lenses are that brushes accumulate dirt and are themselves abrasive, and a big bulb can turn into a sandblaster and actually damage a lens.

I'm not being finicky about clean lenses, I want the dust gone, not a totally clean lens. I want to avoid damage. Do this daily for a few years and I will have repeated the process a thousand times, that's a lot of cycles.


Edmund

Hi Edmund,
I wrote the first short answer for you, the longer one for people interested in this topic more in general.
Thanks
Michael

 

[eronald]

Hi Edmund,
I wrote the first short answer for you, the longer one for people interested in this topic more in general.
Thanks
Michael

Michael yes, I will order a big Giotto Rocket, I need one anyway. Let's see whether anyone here has another trick.

I'm actually surprised I get so much dust on the Ultravid,

Edmund

 

[[email protected]]

https://www.amazon.com/Giottos-AA1900-Rocket-Blaster-Large/dp/B00017LSPI

 

[Binastro]

Hi Edmund.
Personally, in your situation I would use some kind of quick every ready case.

I carried My Minolta SRT 303B and 101s in every ready cases with a strap around my neck.
After ten years of daily use these cameras looked almost as new. At the annual free Minolta tests, the Minolta guys were amazed how clean the cameras were. They looked almost new. The shutter speeds were slightly off and they adjusted them. They were used down to minus 35C.

I have seen professional Nikon camera men with truly awful looking cameras. I don't think that this is necessary even for professionals.

I could get a photo in about one second. I would drop the front of the case. The close fit lens cap was just dropped down into the lower part of the case. This rubber cap had both inner and outer surfaces that gripped the lens. No stupid grip that has to be squeezed.
The camera was preset for aperture and speed and focus time was almost instant.
Modern cameras are not nearly as fast, although they claim to be.

If an every ready case is available for binoculars then it should also take one second to use.
I don't think it is necessary to get optics dirty.

If the binocular really has to be uncovered, I would consider multicoated clear filters if the binocular has threads. At least some of the Canon IS binoculars have these. There is then some problem with ghosting, but filters can be cleaned and replaced as necessary.
I think that Kowa spotting scopes have front and rear threads.

Regards,
B.

P.S.
Are there any fake Giotto bulbs being sold?

 

[Apochromat]

The Original GIOTTOS comes in a fitting and sliding plastic packing with the ads printed on the removable cardboard back. You can store it inside. I think it is not very likely that fakes of this product are around.
Thanks
Michael

 

[WJC]

So I carry my Ultravid HD with no objective covers under my jacket every day.
I have a raincatcher, so the oculars stay fairly clean.

Unsurprisingly, dust accumulates on the objectives.

I just want to get rid of the dust - not clean the lenses.

Advice?

PS. I know how to *clean* my lenses. This is a case of *not* wanting to use that process. I want to do as little as possible.


Edmund

Just a related thought. :cat:

Bill

 

[fazalmajid]

The small Giotto blower doesn't do much good, the big one is just OK.

I use a quick burst of canned air on mine. Not long enough that liquid propellant starts coming through. Camel's hair brushes also work very well (specially the ones that look like a lipstick so you can protect them from dust when not in use.

 

[eronald]

Just a related thought. :cat:

Bill

Bill,

I agree entirely. Random crud on the objective is no real bother as it is far from the focal plane. But when the dust looks like it could be the start of a decent blanket it does start adding to veiling glare. My objectives really accumulate dry dust - maybe it's an electrostatic effect.

I never had such dust on my camera lenses. For a period of my life I was a fashion photographer. I very rarely cleaned my lenses. As you point out, crud on the front of a tele hardly matters. However, filters can be catastrophic, I stopped using them when Canon and I finally figured out that an autofocus issue I had with a Canon 85 1.2 lens was due to the protection filter - which happened to be a Canon product (!).

Interestingly, dirt next to the oculars is a very real and -to-me- totally unexpected issue. I had a white dash that kept floating in my eyes today while using the binos with eyecups extended. On inspection, it turned out to be a white fiber *entirely on the opaque edge zone* of an ocular, next to but well away from the lens. Way away from the optical path. I couldn't believe it.

Cleaning of a user glass at a service center or retailer is done ONCE on an instrument and so any method that results in decent cleaning is of little consequence if it works and doesn't impact the state of the lenses. However user cleaning eg. of the oculars will be done hundreds of times over the life of an instrument eg. 50 times a year for ten years = 500x, so the method employed by an enduser for a regular cleaning should be much more gentle, considerably less abrasive and more risk free, than the one employed by an expert for service. I don't want to notice that the coating has been sanded off my lens in a couple of years, and that the culprit happens to be me

Edmund

PS. My local Zeiss retailer told he cleans the lenses of his display instruments every day. I guess that's why they invented "demo" sales

 

[John A Roberts]

Specifically re dust removal:

I’m also a fan of using the Giotto large blower, while holding the lens facing downward
However, as many small particles are only attached to a lens surface by static charge I also use an anti-static gun, both before and after the blower
While not essential, anti-stating makes the job easier (where I live, humidity is low for much of the year. Static may not be the same concern in more humid localities)

Oldsters and Hipsters will know that an anti-static gun is analogue era technology, for use on vinyl records
They were most commonly marketed under the Zerostat brand (and are again available though expensive)
If you can find one tucked away in an unused vinyl collection, or can pick up a used one cheaply, give it a try

With lens cleaning we always need to keep a sense of proportion,
as Bill and others have indicated many times, especially with objective lenses, a significant amount of specks on the surface will usually have an insignificant effect on performance


John

 

[Pileatus]

So I carry my Ultravid HD with no objective covers under my jacket every day.
I have a raincatcher, so the oculars stay fairly clean.

Unsurprisingly, dust accumulates on the objectives.

I just want to get rid of the dust - not clean the lenses.

Advice?

PS. I know how to *clean* my lenses. This is a case of *not* wanting to use that process. I want to do as little as possible.


Edmund

Lungs and a camel hair brush have served me fine for a few decades. Any dust that doesn't go easily requires a formal cleaning.

 

[eronald]

Specifically re dust removal:


With lens cleaning we always need to keep a sense of proportion,
as Bill and others have indicated many times, especially with objective lenses, a significant amount of specks on the surface will usually have an insignificant effect on performance


John

I guess I'm going to repeat that to myself.


Edmund

 

[John A Roberts]

Edmund

Having over the years done more harm than good to a few camera lenses with over insistent cleaning, I'm very cautious in this regard
('I'll just get rid of this last speck so it'll be perfectly clean' . . . and instead a permanent blemish!)
- with lens cleaning it's often the case that 'the perfect is the enemy of the good'

John