Lens Coating Query, Help Please

[MattKing]

It's unlikely, modern coatings are very hard and you'd easily spot damage it there was any.

It's not a modern camera eek! It's an Olympus RC 35 with a fixed 2.8 Zuiko lens, thanks!

is this the case with older lenses too? this particular camera is from 1970!

When it comes to lenses, methinks that you may have different definitions in mind for terms like "modern" and "older" than Ian does (or I do, for that matter).

When some of us talk about things being old, photographically speaking, there are often references to things like World Wars, and not always the second one.

 

[Thomas King]

When it comes to lenses, methinks that you may have different definitions in mind for terms like "modern" and "older" than Ian does (or I do, for that matter).

When some of us talk about things being old, photographically speaking, there are often references to things like World Wars, and not always the second one.

Oops! I'll note that for next time!

 

[Thomas King]

No, it impairs the ability of the cloth to absorb contaminates on the lens surface.
I throw mine in the washer with a load of permeate press and cotton shirts, Tide detergent without fabric softener, then air dry. They always clean like new.

Unless that chemical was lacquer thinner or similar don't worry. Chlorine bleach might harm the coating also as will scotch brite scouring pads.

Leave it and enjoy the camera!! The only thing they're good for is making pictures! But do put the filter on, preferably a multicoated one.

Hi, would you give the same answer if i told you that i'd been cleaning the lens too much? Only since i got it so two days but i have been wiping a lot not knowing the risks! if i don't do it from now on and use a uv filter instead should i be ok?

 

[shutterfinger]

Camera store sales people always recommend a UV filter because its an add on to the sale.
As you noted there are two schools of thought on this subject so choose the one that suits your needs as both are correct.

Any chemist want to refute my comments on the household cleaner?

 

[Thomas King]

Camera store sales people always recommend a UV filter because its an add on to the sale.
As you noted there are two schools of thought on this subject so choose the one that suits your needs as both are correct.

Any chemist want to refute my comments on the household cleaner?

Thanks, would you give the same answer (not to worry) if i told you that i'd been cleaning the lens too much? Only since i got it so two days but i have been wiping a lot not knowing the risks! if i don't do it from now on and use a uv filter instead should i be ok?

 

[Poisson Du Jour]

Thanks, would you give the same answer (not to worry) if i told you that i'd been cleaning the lens too much? Only since i got it so two days but i have been wiping a lot not knowing the risks! if i don't do it from now on and use a uv filter instead should i be ok?

A lens — any lens on any camera, should never be attacked with excessive zeal and enthusiasm in the absence of experience. Many lenses can indeed be scratched by people with limited skill or experience in cleaning, also filters! How would you manage cleaning a $700 B+W KSM circular polariser? Or a $6,000 lens? Even the best of us seek professional advice for these things (it is true that some lenses can be scratched by the humble tissue!), or at the very least, use a very, very fine microfibre cloth and extreme caution. For you though, the best advice is to leave the lens alone, and put on a filter to provide protection. Even a light smear or smudge on the lens is most unlikely to have any effect on the image.

 

[Thomas King]

A lens — any lens on any camera, should never be attacked with excessive zeal and enthusiasm in the absence of experience. Many lenses can indeed be scratched by people with limited skill or experience in cleaning, also filters! How would you manage cleaning a $700 B+W KSM circular polariser? Or a $6,000 lens? Even the best of us seek professional advice for these things (it is true that some lenses can be scratched by the humble tissue!), or at the very least, use a very, very fine microfibre cloth and extreme caution. For you though, the best advice is to leave the lens alone, and put on a filter to provide protection. Even a light smear or smudge on the lens is most unlikely to have any effect on the image.

Thanks for this, i'll more more careful in future. But am i ok in the meantime? Do i have anything to worry about in terms of lens damage?

 

[shutterfinger]

But am i ok in the meantime? Do i have anything to worry about in terms of lens damage?

You have destroyed it! Send it to E. von Hoegth or myself for disposal.

Serious answer, likely not, once the lens is clear further wiping is unnecessary.

 

[Thomas King]

You have destroyed it! Send it to E. von Hoegth or myself for disposal.

Serious answer, likely not, once the lens is clear further wiping is unnecessary.

ok but now ONE last question... would you give the same answer if i told you that i'd been cleaning the lens too much? Only since i got it so two days but i have been wiping a lot not knowing the risks! if i don't do it from now on and use a uv filter instead should i be ok? sorry for worrying so much!

 

[shutterfinger]

ok but now ONE last question... would you give the same answer if i told you that i'd been cleaning the lens too much? Only since i got it so two days but i have been wiping a lot not knowing the risks! if i don't do it from now on and use a uv filter instead should i be ok? sorry for worrying so much!

Put the lens cap on and sit the camera in a safe place.
When the film gets there load a roll and go ask the camera, it will tell you the truth.
Download a copy of the instruction manual if you need one at http://www.butkus.org/chinon/olympus.htm

 

[shutterfinger]

Set the camera to Manual mode. Set the aperture to f2.8, set the focus to indicate infinity on the lens. Look through the viewfinder at an object/target at least 1524 meters away and verify that the rangefinder indicates an "in focus" condition. Refer to the instruction manual if necessary. Now set the focus to 25 feet/7.62 meters and measure from the film plane (the rear of the hot shoe/camera back) to a target and verify the viewfinder indicates correct focus. Repeat this test for 15 feet/4.572 meters, 10 feet/3 meters, and 6 feet/1.8 meters.
If the rangefinder does not indicate correct focus at the measured distance ± a few centimeters then have the camera serviced as pictures taken will likely be out of focus/ focused on some other object in the scene than the one you focused on.

 

[jim10219]

Here’s my method for cleaning lenses. Always use a blower to clean the lens. That way you don’t drag dust particles across the lens and scratch it. If the blower won’t do it, then use a lens brush. Make sure to keep the lens brush clean, and never touch the bristles. Use the blower to clean the brush, or soak it in isopropyl alcohol if nessary (like if you get skin oil on it). Always the purest isopropyl alcohol you can find, cause the other stuff has water and water can leave droplets. If the brush and blower won’t clean it, then move on to the microfiber cleaning cloth. Always use a separate section of the cleaning cloth, so you don’t spread the contamination. When it’s time to clean the cloth, just wash it in a cup with water and a drop of laundry detergent (I use dye and perfume free for sensitive skin), ring it out, and hang to dry. Don’t use fabric softener, cause that stuff will leave a film. If the microfiber cloth alone won’t do it, use a microfiber cloth with isopropyl alcohol or lens cleaning solution.

That’s the order, and it works pretty well for me. Also, I’ll say don’t sweat a few tiny dust particles. I find they rarely make a difference in the real world. The more you get into photography, the less you worry about dust and scratches. I also don’t use filters for protection. Lens caps do a better job, and cheap filters can add flare and be harder to clean than lenses. Multicoated filters aren’t cheap, and I can’t afford to buy a new one for every lens I own. But if the trade off is worth it to you, then go for it. The reason the filter debate continues to rage on is because either method is equally valid. Neither is right or wrong.

 

[BrianVS]

Get a good air blower. That will get dust/grit off of it.
Unless you get oil/grease on the lens, you should only have to clean the lens with paper or a cloth when haze builds up on it. That can be years.

I normally keep filters on a lens. I have 80 year old coated lenses, coating in great condition. I use eye-glass cleaner when necessary, with a Q-Tip, sometimes wrapped in Tiffen lens cleaning paper. I've had lenses that look like wax paper when received. Most cleaned up perfectly.

This lens is 90 years old.

Carl zeiss Jena 4cm F1.4 Biotar by fiftyonepointsix, on Flickr

The "tarnish" on the lens acts like a coating. Fragile! The lens was almost opaque when received.

 

[Thomas King]

Get a good air blower. That will get dust/grit off of it.
Unless you get oil/grease on the lens, you should only have to clean the lens with paper or a cloth when haze builds up on it. That can be years.

I normally keep filters on a lens. I have 80 year old coated lenses, coating in great condition. I use eye-glass cleaner when necessary, with a Q-Tip, sometimes wrapped in Tiffen lens cleaning paper. I've had lenses that look like wax paper when received. Most cleaned up perfectly.

This lens is 90 years old.

The "tarnish" on the lens acts like a coating. Fragile! The lens was almost opaque when received.

Thanks for this, is it safe to say i haven't done any damage by over-cleaning in these first couple of days. camera has now been put away and will not be touched again until i go out and shoot!

 

[OlyMan]

Hi Thomas if you're still debating whether to protect the lens with a filter and you're wondering where to buy such an odd size (43.5mm I think), remember the more plentiful Olympus Trip uses the same thread. A quick search of UK ebay for "trip 35 filter" shows new ones for sale for £3.99. If you're concerned a cheap filter will degrade the image, then pretend it's a lens cap and unscrew it when you shoot. Speaking of which, a lens cap wouldn't go amiss either if you don't have one, again searching for 'Olympus Trip Lens Cap" will return more results. Don't bother with the original friction-fit Olympus lens cap: most are too loose by now and fall of in a breeze. Look for one which clips on.

 

[Thomas King]

Hi Thomas if you're still debating whether to protect the lens with a filter and you're wondering where to buy such an odd size (43.5mm I think), remember the more plentiful Olympus Trip uses the same thread. A quick search of UK ebay for "trip 35 filter" shows new ones for sale for £3.99. If you're concerned a cheap filter will degrade the image, then pretend it's a lens cap and unscrew it when you shoot. Speaking of which, a lens cap wouldn't go amiss either if you don't have one, again searching for 'Olympus Trip Lens Cap" will return more results. Don't bother with the original friction-fit Olympus lens cap: most are too loose by now and fall of in a breeze. Look for one which clips on.

Thanks for this info... I have looked on Tripman which seem to have some good filters for the Olympus Trip for around £15. I already have a lens cap so I think i'll invest in a good filter too. I'm just worried that I have been cleaning and fiddling with the lens too much. I have been wiping with a soft microfiber cloth gently a few times but now I know i'm not supposed to do that! Will I have caused any cleaning marks or damage to the lens? I think a UV filter would save me from my own stupidity. Looking forward to your response!

 

[Nodda Duma]

As a lens designer who has handled countless optics in and out of the optical shop, I will say the advice on minimizing cleaning applies to professionals as well. If you clean your optics daily, the coatings will not last like you believe -- even with the type of cleaning methods that would be employed on million-dollar optics.

Cleaning is not the only way to damage coatings. Exposure to the elements through normal use during outdoor photography can risk coating damage. Finally, unless you keep it in a vault, there is always the risk of damage in an accident.

My professional recommendation: Use a protective filter!

All good advice for amateur or beginner, most pros only use filters when they are required.

My lens will degrade from cleaning in 200+ years if cleaned daily because I use good cleaning practices.
A UV or skylight filter is not a necessity!

an op

 

[AgX]

as said above:
Filters under circumstances may degrade image quality.

With standard means as loupes, I could not yet detect harm done by my cleaning. Though some day I shall do some eleborate test with a microscope.
(All my lenses I bought used. And most of them are filthy, to the degree of being useless. Thus at least with my first cleaning they only can become better...)

 

[Nodda Duma]

as said above:
Filters under circumstances may degrade image quality.

With standard means as loupes, I could not yet detect harm done by my cleaning. Though some day I shall do some eleborate test with a microscope.
(All my lenses I bought used. And most of them are filthy, to the degree of being useless. Thus at least with my first cleaning they only can become better...)

Coatings suffer physical damage during cleaning in a process similar to (but not as fast working as) optical polishing: with a cleaning session, you wipe away a few Angstroms off the top layer of the coating material. Over several cleaning sessions, this will cause a shift in the spectral transmission characteristics that can be revealed in measurements with a scatterometer or spectrophotometer. As cleaning continues, transmission is reduced. The outer layer will also thin out, and if wiped completely away, the softer inner coating layers (on multilayer coatings) will be exposed to humidity which will cause damage including the potential for delamination. That's how I've seen coating failure proceed due to over-cleaning.

 

[AgX]

So far I did extensive tests based on visual examination. And I did not experience any variation in reflection.
But nevertheless you may be right.

But still I would like to see the effect in the image of just the front coating gone complety.

 

[AgX]

And what about the protective filter being cleaned?
The adverse effect of cleaning than just would be transferred to that filter and furthermore two unfavourable reflective planes introduced.

And why then did the lens industry not offer optically better protective filters? Best customised for the very lens. Regarding them as consumables would mean an extra business for them.

 

[Ian Grant]

When it comes to lenses, methinks that you may have different definitions in mind for terms like "modern" and "older" than Ian does (or I do, for that matter).

When some of us talk about things being old, photographically speaking, there are often references to things like World Wars, and not always the second one.

Well caught.

Yes my concept of old and modern differs, old can mean uncoated pre-WWII lenses in shutters or even older brass lenses. By modern coatings I mean hard coatings, not the early post WWII Kodak and other US bloomed lenses. The coatings used by CZJ 1938 onwards were much harder and seem resistant to cleaning scratches (if cleaned carefully), to me they are modern coated lenses..

It's not just the coatings though some optical glass is very significantly softer than others, classic examples are the Novar, Domiplan, Summar, all used the same Schott glass for their front element.

As others have said keep cleaning to a minimum, a brush or blower helps.

Ian

 

[AgX]

Another approach is:

"Use always a protective filter, unless..."

...you are in a calm situation with nothing to affect the lens and when you are not bothered to take the filter off, put it aside and later on again.

 

[Nodda Duma]

Another approach is:

"Use always a protective filter, unless..."

...you are in a calm situation with nothing to affect the lens and when you are not bothered to take the filter off, put it aside and later on again.

That's what I tend to do, and I was kind of anal about choosing a filter.

For work, I specify the coatings so they will survive specified environmental conditions. When the front coating inevitably becomes damaged in the field, the mechanical engineer and I ensure the assembly design accommodates depot-level (or factory level) replacement of the front optic. Repair support is pretty standard fare, but obviously it's a different world than the consumer market.

 

[MattKing]

I'm just worried that I have been cleaning and fiddling with the lens too much.

Why are you worrying about what you have already done?
Blow any loose dust or dirt off of the lens, put a protective filter on it, load some film and then enjoy your camera.
I'll bet that it will give you lots of great results.
If you want to spend some productive energy, learn as much as you can from the manual, read up on some of the techniques about holding the camera, using a rangefinder, dealing with complex lighting situations and composing through a rangefinder window.
But most importantly, have some fun!