Sensor cleaning

[pbertner]

Especially pertinent to Macro work, I haven't had a problem with sensor dust until I've started shooting at 10X.

I know the traditional methods of cleaning ie. Blower, clean wipes, sensor brush.
My problem lies in that the blower doesn't remove all the dust specks, the wet clean wipes in addition to being expensive leave spots in the corners unless your technique is impeccable. Sensor brush can also spread the dust rather than remove it. And I've found that after several cleanings a sensorklear pen kind of frays leaving more debris behind than it removes.

Lately I've been doing what I'm sure no one would recommend. Instead of using a hurricane blower I've been blowing the good old fashioned way. This condenses on the sensor as a fog. Then I use the sensorklear pen. The humidity on the sensor ensures that the debris that usually is left behind by the pen clings to the pen much better. After a thorough wiping in this manner I'll use one sensorklear wet wipe to go over the sensor. I've found this method to be remarkably effective.

Now I'm just curious to hear from those that have an intimate knowledge of the workings of cameras if this poses any potential hazards to the sensor or camera in general. I don't see it proving more of a problem than the general humidity of the rainforests in which I usually work.

All comments and opinions are welcome,
Paul

[SONYNUT]

I don't know what the big deal is

[rjlittlefield]

I've moved this to Technical as it seemed out of place in Nature Photography, even with SONYNUT's illustrative addition.

Paul, I agree with your judgment. Unless you're seriously ill or about to be, there shouldn't be anything in breath condensate that's not on the approved-for-sensors list. Even small drops of liquid saliva should be harmless to the coating, and whatever gets left behind will come off clean with a wet swab.

--Rik

[ChrisRaper]

It sounds like a fairly benign way to clean the sensor - I will give it a try when I have to do a clean My only thoughts would be perhaps to make sure that the inner workings dry completely before putting the lens back on - your breath will coat all of the surfaces with humidity. Perhaps leaving the body overnight in a tupperware box with some silica gel bags would make sure that all residual humidity had been sucked out?

[seta666]

I allways recomend sensor-film http://www.sensor-film.com/
It look scary but if you follows the instruction is very safe and removes all dust, doen not just put it to the sides.
The trick is to paint the whole sensor with the product, wait half an hour an redo the borders and corners as the product shrinks a bit whle it dries
I do it once every 1/2 months for a thorough clean
There are two kind of products, for older sensors and newer ones with fluoride coatings
The only con it has is that it takes around 3 hours
Regards
Javier

[ChrisR]

I feel like I'm hounding Javier about this , but it pertains to a problem I had:
If you get oily smears on your sensor, which is apparently quite common as lubricants can migrate from within the camera, Sensor film makes them worse.

[Craig Gerard]

http://www.copperhillimages.com/index.php?pr=tutorials

http://bythom.com/cleaning.htm

http://www.cleaningdigitalcameras.com/methods.html

There are 'levels' of cleaning as outlined in Thom Hogan's article and different approaches are required for particular contaminants.

The links above provide a reasonable range of opinions and technique in regard to various products and should be read with some discretion.



Craig

[abpho]

The actual sensor is protected by the hot mirror. A piece of glass used to block UV and IR light.

I have heard others saying it is a bad idea to breath on a lens to clean it. But I hot much better results doing that versus using an actual lens cleaning solution. The solution left greasy streaks where the moist breath method left the lens sparkling clean.

Sensor film sounds scary. If I knew that the hot mirror was completely sealed around the edges and no liquid could ooze into any small crevasses I might think about it. UPDATE: WOW! Up to two hours the mirror has to stay up!!!! Does a battery last that long?

I find that trying to get descent information out of anyone regarding sensor cleanings to be a pain in the buttocks. Some camera manufacturers tell you to send the camera in for cleaning. No one will tell you what to use on your specific sensor. No one wants the liability. I ended up going with a blower, the arctic brush, and disposable wet wipes. All three methods have their place.

[Chris S.]

And here http://photomacrography.net/forum/viewt ... 2964#82964 . Not necessary to read the entire thread, but my post, and Charlie's post six entries above it, say some important things not covered at the three sites Craig listed, nor anywhere else I've seen on the Web. One point is that it is very difficult to clean off dust that you can't see. With the naked eye, the small stuff is invisible. Even with a sensor loupe, the really small stuff is invisible. This really small stuff might not be noticed by the average photographer, but to a photomacrographer, it can be a deal breaker. I couldn't clean a sensor without a dissecting scope, and Charlie, in his post, said much the same thing.

And there are sins of commission, as well as ommission, at those sites. The Copperhill site seems to be pushing their own "SensorSwipe" product. It might be a nice product, but they are mixing information with advertising without drawing clear boundaries between. And they use false logic in condemning adhesive products for all cleaning. As Chris R. pointed out, if there is grease on the sensor, only a wet cleaning will remove it. And lube on the sensor is very, very common for the first few cleanings. Perhaps with some cameras, it continues after that, though in my experience, it's ceased to be a big issue after a while. At this point--or in any cleaning after the grease is removed--adhesive methods can be very useful. Javier uses Sensor Film, Charlie uses removeable glue dots, and I use tape. Having something adhesive in the tool kit is a big help for things like textile fibers.

The "cleaningdigitalcameras.com" site has quite a few errors, but the following bit of rubbish warrants emphasis: ". . .you must take into consideration that standard medical grade methanol isn't nearly as clean as Eclipse™. Eclipse™ is refined Methanol with a specifications of 5ppm (parts per million) or less of contaminants, where as standard medical grade can have a specification of 500ppm or less of contaminants. This contaminant is what can leave a white film on the surface."

Nonsense! First, the phrase "standard medical grade methanol" is eye-popping, as methanol is a poison, not a standard medical supply. They might be thinking of hardware-store methanol (from the paint department)--and if so, it cleans sensors just fine. Or they might be thinking of drugstore isopropanol, which is a completely different chemical--but also works just fine for cleaning sensors. So does vodka from the liquor store. Their claim that "this contaminant is what can leave a white film on the surface" is misleading; the white film that many people see on their sensors, after an attempt at cleaning, is not from "contaminants" in the alcohol. It was already there as sensor gunk, got dissolved during the cleaning process, and redeposited as the alcohol dried. The fix is not to get purer alcohol, but to wipe up the alcohol before it dries.

To this end, claims that faster evaporation is always better aren't quite right--you certainly want something that evaporates if you get a stray drop into a nook or cranny, but not something that evaporates before you can swab it up. If my alcohol is evaporating too fast, I water it down a bit.

Cleaning a sensor is quite a bit like mopping a floor. People would laugh if I tried to sell them expensive, highly-purified water to fill their mopping bucket. "Oh, but my trademarked Voodoo Water has fewer contaminants than your tap water!" While perhaps true, it won't make much difference to your floor, because far, far more "contaminants" are already on that floor. The purpose of the water is to dissolve and suspend them so that you can suck the water--and the dirt--up with your mop.

Thom Hogan has changed his advice since the last time I read him on this subject. His current reliance on pre-moistened swabs would be very expensive to many of us macro folks. I carry a few for emergency cleanings in the field, but at $5 a throw, I would never use them for every day. The other day, I cleaned four sensors (two of my own, and two for a friend). Went through maybe 20 swabs? Since I redo my own with Pec pads, this is no big deal. But a hundred bucks? I can think of better things to do with that money.

[Craig Gerard]

Chris,

That's what I meant by "should be read with some discretion"

Working at the magnifications to which we are accustomed does present additional challenges with regard to effective sensor cleaning.

I couldn't bring myself to pay for more Photographic Solutions clean room prepared swabs @ $45.00 for 12 swabs, I couldn't pay that much for so little in return.

Notice also, how Copper Hill do not speak highly of the Dust-Aid products, yet Thom Hogan does mention them as appropriate. In the example on the Copper Hill website the Dust-Aid issue was more related to user error .i.e. using the wrong product for the particular contaminate.

I've recently purchased products from Copper Hill and Dust-Aid (Dust Aid Platinum and Sensor Swabs). Used my last Photographic Solutions Sensor Swabs last night.

Question: What location/room do you prefer to use when performing a sensor cleaning operation?



Craig

[Chris S.]

That's what I meant by "should be read with some discretion"

Hey, Craig, did you by chance add this comment to your post while I was typing? I was interrupted several times, so "typing" lasted a while. Regardless, my comments were not meant toward you, a champion at supplying good sources of information. These are, indeed, among the best of what's out there (that I've seen, anyway--but I've looked quite a bit) on this subject. What I was commenting on was the current, dismal, state of information on this subject. Perhaps we should start a FAQ.

Working at the magnifications to which we are accustomed does present additional challenges with regard to effective sensor cleaning.

Doesn't it, though? My dad is a photographer who never shoots macro--and in fact is likely to be chasing his grandaughter and be shooting wide open--so I don't have to be as fussy when I clean his camera's sensor. Perhaps that's why the professional cleanings I've seen have tended to be poor, in my opinion--clean enough for most people isn't clean enough for a high-magnification photographer.

Notice also, how Copper Hill do not speak highly of the Dust-Aid products, yet Thom Hogan does mention them as appropriate. In the example on the Copper Hill website the Dust-Aid issue was more related to user error .i.e. using the wrong product for the particular contaminate.

I thought the same thing about Copper Hill's disparagement of the Dust-Aid products--it's part of what I meant by "false logic." I was considering it a variation of the "straw man" fallacy.

I've recently purchased products from Copper Hill and Dust-Aid (Dust Aid Platinum and Sensor Swabs). Used my last Photographic Solutions Sensor Swabs last night.

I have a hodgepodge of sticks from various companies, covered with bits of Pec pad. I also like a pencil eraser covered with Pec pad for stubborn spots, and a McDonald's coffee stirrer covered with Pec pad for edges and corners. The pre-cut strips of Pec pad from Copper Hill seem attractive, in that my hand-cut ones do drop a few stray fibers here and there. I find these fibers very easy to get rid of, but not dropping them in the first place would have its merits. That said, Copper Hill's use of a fallacy in the attack a competitor--especially in a format that conflates education with marketing--makes my lips curl. Might be a nice product, but can I bring myself to order it?

Question: What location/room do you prefer to use when performing a sensor cleaning operation?

Here at home, a bar separates the kitchen from the living/dining area. The kitchen is very well lit, and this light shines on the bar. The bar chairs are of a height I find comfortable for work like this. Additionally, the bar is very solid, and provides a good support for my dissecting scope. So that is where I clean sensors.

But there is a downside, as airborne dust falls into the sensor even as I work. I've had thoughts of building something that resembles the fume hoods used in laboratories, but in reverse--a box, with lights, a window, a hole for my hands, etc. A fan would pull air in through a HEPA filter, and the air would exit around my hands. Not a clean room, but a clean(ish) box. This is, of course, not an original idea--it was well known years ago when I knocked a similar box together for handling petri dishes of agar, which are easily contaminated.

Meanwhile, my current final step is to blow the sensor well with a Giotto blower while holding the camera facing downward, and putting a body cap on the camera before turning it upright. The fresh-fallen dust tends to be rather loose and fairly tractable to this approach.

Cheers,

--Chris

[Harold Gough]

Especially pertinent to Macro work, I haven't had a problem with sensor dust until I've started shooting at 10X.

Why should that be so? The sensor doesn't know what magnification you are using. Surely, at the sensor, an image is an image, whatever the subject, lens, etc.

Harold

[Craig Gerard]

Chris,

I did edit that post just before Mischa responded, but before your post. My post was originally much longer; but I reduced it somewhat.

The three links were added to counter the claims made in some of the individual articles and to provide a broader overview of product 'pros and 'cons' in an attempt to achieve a practical balance of opinion and discern a methodical practice.

The links to various sensor cleaning approaches were also added due to the title of the thread, for the benefit of current and future readers searching for such information and to compliment the methods mentioned by Paul and Javier. The link you added to a more detailed discussion is also a valuable inclusion.

I'm of the opinion that a device such as the NRD Firefly Sensor Cleaner has a role to play in removing dust from inside the camera and as a consequence non-welded dust from the sensor (low pass filter). It may also be more efficient than a standalone rocket blower as a final step after a liquid swab and could also be used on the rear of lenses and exterior of the camera body prior to a lens change? I can't get my hands on such a device.....is anyone using the NRD Firefly Sensor Cleaner? It is cheaper to buy it direct from the NRD website (US Residents Only) ($125.00) than it is to purchase from Adorama ($159.95).

Here is a brief, impartial review.
http://photography-on-the.net/forum/sho ... p?t=874817

and another link:
http://www.ppmag.com/web-exclusives/201 ... refly.html

and a link to a video I added to another post somewhere:
http://youtu.be/ZCc8x0V9nCA



Craig

[Chris S.]

Craig, this makes sense. Since I hadn't participated in this thread until my post, I didn't get email updates. So when I responded to you, I was unaware of Mischa's post and your updates. Your post was interesting to me, so I responded to perhaps the earliest version of it. And Mischa is right!

But this is moot--your links and comments, as always, add value. Your post provided perspective, and gave me a chance to rail against the widespread misinformation regarding sensor cleaning that is current on the Web. I'm beginning to draft a FAQ on sensor cleaning (thanks, Rik, for the urging). Will show you and others a draft for comments and edits before posting.

I feel--strongly--that those of us who have cleaned quite a few sensors should share our experiences, and aggressively deflate marketing puffery. Sensor cleaning is only a little more mysterious than washing dishes, washing hands, or mopping floors, despite all the nitwittery promulgated on the Internet. There are simple, inexpensive, protocols that lead to a squeaky clean sensor. This forum is the place to make those methods clear.

Cheers,

--Chris

[Chris S.]

Especially pertinent to Macro work, I haven't had a problem with sensor dust until I've started shooting at 10X.

Why should that be so? The sensor doesn't know what magnification you are using. Surely, at the sensor, an image is an image, whatever the subject, lens, etc.

Harold, I was hoping that one of the many members of this forum whose grasp of optics exceeds mine would respond. But in the meantime, I'll give it a shot.

Empirically, as magnification increases, so does the the clarity of sensor dust in our images. I've definitely seen this--a 4x lens is vastly more tolerant of sensor grunge than, say, a 60x or 100x objective. As I understand it, as we increase magnification, we tend to decrease nominal aperture--effectively, we move closer to having a point light source. And a point light source is very effective at imaging sensor dust.

I once attended a lecture by the late, and truly great, Harold Edgerton--aka "Papa Flash." I don't recall if it came up during his lecture, or in our conversation afterward, that he had made useful images of bacteria by placing them on a piece of film and hitting them with a flash placed far enough away to act as a point light source. It struck me as a very cool way of imaging bacteria. But as we increase magnification, we are unfortunately doing much the same thing with sensor dust--moving toward a point light source that images the dust very acutely.

Those more erudite in optics will hopefully correct my errors in this explanation. But this may be a decent "horse sense" way of looking at it.

Cheers,

--Chris