[Leica] Sensor cleaning revisited - smears after cleaning

[douglas.sharp at gmx.de (Douglas Sharp)]

Hi Geoff,

I have had the same problems with sensor cleaning.

There are a few things that can lead to it:

1) as you mentioned, touching some part of the camera other than the 
sensor with your swab.
2) not letting the fluid soak in long enough - 30 seconds at least
3) using too much fluid
4) grease from fingers on the swab (or the swab may have touched 
something before it was used on the sensor, did it rest on something 
while soaking up the fluid?)
5) a small but thick greasy stain on the sensor - can take up to 4 
passes to get rid of it
6) using the same swab for two or three wipes
7) grease spots from a dirty Arctic Butterfly brush or lenspen (had this 
lenspen problem, don't use them any more)

By the way, and this really happened to me with my Canon 300D, don't 
sneeze or cough while cleaning your sensor, it's just asking for trouble.
(And keep cats away from your desk when cleaning).

I have to clean my sensors about once every 2 weeks because we have a 
cement works just up the road from here - well known for discharging 
nano particle dust. We made the mistake of buying a black car - nuff said.

If it still applies to any of you - smoking is about the worst thing 
that can happen to sensors - the tar and micro-particles in the air just 
go looking for sensors and find their way into cameras even with lenses 
attached. The cool, metal or glass parts in cameras are perfect surfaces 
for any warmer airborne stuff to condense and precipitate on

Same applies if you keep or open your camera anywhere near the kitchen, 
fat droplets and water vapour will soon find your sensor.

Fact is that most of the dust and spots are almost invisible to the 
human eye, but still show up in your shots.

Sensor spots and stains are a "bu--er" to get rid of, but I suppose it's 
a down side of digital there had to be.

Cheers
Douglas

On 03.03.2010 03:07, Geoff Hopkinson wrote:
> I had a recent exchnge on and off list regarding cleaning the M9 sensor.
> When I just cleaned mine ( which has not had heavy use), I was dismayed to
> find that I had persistent streaks, some of which looked alarmingly like
> fine scratches.
> I was confident that I had been careful. I used the Arctic butterfly brush
> first to remove any loose dust and then did a careful wet pass with Visible
> Dust Plus. I only had 1.3x size swabs.
> The streaks remained after 3 separate cleaning cycles with new swabs each
> time.
> I repeated this all with the Dust Aid kit which uses swabs that you need to
> manually wind around the spatula and their fluid. Same result. My Leica
> dealer repeated this, same result.
> We could not budge the easily visible streaks although they were completely
> undetectable on test images at high magnification on a monitor.
>
> Today I repeated the dry clean folowed by a wet clean with the Eclipse type
> 3 (size) swab and their fluid. They no longer consider the E2 fluid
> necessary for tin oxide sensors and recommend their standard fluid for 
> every
> sensor.
> A single pass in each direction completely removed every trace of the
> streaks and I am a happy camper. I believe that the streaks I had were
> either traces of oil, possibly from the swab touching the surrounds of the
> sensor (shutter lubricant??), drying marks from the fluids used (qty?) or a
> combination of both.
>
> I note that the Eclipse fluid contains methanol.
> Visible Dust fluid does not and they state that methanol can damage the 
> seal
> of the covering bonded to the sensor.
> Leica recommends isopropyl alcohol.
> In any event I wanted to report my experiences. I'm sure that others will
> have had different experiences and views. Incidentally the Eclipse swabs
> actually cost even more here than the Visible Dust products so that should
> please those who considered I was skimping by trying the Dust aid swabs 
> when
> my Visible Dust ones (M8 size) ran out!
>
> Cheers
> Geoff
> http://www.pbase.com/hoppyman
>
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