M240 sensor corrosion

[islaloha]

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Hi everyone,

I just bought a M240 and after first check it seems there are some marks on the photos. I started to freak out because it reminded me of my old M9P... Tho the sensor looks ok, no visible marks on it.

Here is a photo of the screen after the "dust detection". The marks look quite big, what do you think ? 

 

Thank you for your help 

 

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[jdlaing]

So clean the sensor.

[marchyman]

So far all I've had to do to get rid of similar dust spots is to blow them out using a rocket blower.  Some will say I'm only moving the dust around and not really solving the problem.  Perhaps.   I've done this three times in three years.  It only takes a minute or two.  Because it's so easy it is the first thing I do when I notice a spot in an image.   The third time I did this the spot did not go away... it was on the lens!

[farnz]

On 2/5/2019 at 11:51 PM, Ipanemaguy said:

Beware of lasers such as in concert lightshows, scientific equipment and automotive distance sensors. The laser will burn the lensor because of sudden localized temperatures.

This is nonsense I'm afraid.  Firstly the Class of laser (to BS EN 60825 in Europe) allowed to be used in light shows cannot deliver the level of thermal shock that you're suggesting (if it did then there would be a large number of people with retinal damage) at every concert.  

Secondly, the divergence of the coherent light from the laser's ferule (~barrel) will mean that the spot (Mode Field Diameter) delivered at the sensor will be significantly larger than the MFD leaving the laser and, since it's an Inverse Square Law function, if the spot is twice as big at the sensor then it's power is a quarter of that leaving the sensor.  

Thirdly, the diameter at the laser will be in the micron (micrometres) range so it won't take much for it to double or treble in size, particularly as the beam has to travel through all the lens elements to get to the sensor and each of those elements is designed to modify light rays (an therefore laser beams).  

Fourthly, the inherent dust in the atmosphere will weaken, reflect, and diffract the beam before it even reaches the lens elements.

Consider this myth debunked by a Senior Engineer in the long distance telecommunications field that uses powerful lasers.  If you want to burn your sensor with a laser you need to have the sensor very close to the laser source and the laser needs to capable of delivering several Watts of power; exhibition lasers have a tiny fraction of this capability.

Pete.

[sblutter]

After a long trip my sensor was pretty dirty so I did a wet clean - but some sticky bits(!?) were still there even after a 2nd go.  I went after them with foam cleaning swabs:

https://www.amazon.com/ABN-Foam-Cleaning-Swab-50-Pack/dp/B075MNNV91/ref=asc_df_B075MNNV91/?tag=hyprod-20&linkCode=df0&hvadid=343830699321&hvpos=1o3&hvnetw=g&hvrand=11669879158763711981&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9021731&hvtargid=pla-727862146499&psc=1&tag=&ref=&adgrpid=68719107505&hvpone=&hvptwo=&hvadid=343830699321&hvpos=1o3&hvnetw=g&hvrand=11669879158763711981&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9021731&hvtargid=pla-727862146499

with a drop of cleaning solution which worked very well (don't over wet!) but there were some dust bits I was just chasing around and not removing them.  I wanted it as near to perfect as possible & get tired to fixing the spots in Photoshop - I print all 'finals'. 

I decided to break a Jaap rule and very carefully went after them with a can of compressed air, after bleeding off gas and moisture 1st.  From about 12" away, using pretty soft bursts that I judged too weak to damage the sensor - I got them all off.  Note:  Do NOT shake the can and keep it upright.

Will it stay that clean?  Never, but it was satisfying and now a week later dust detection is still 100% clear.  If you try it, be super careful & do so at your own risk.  The rocket blower isn't strong enough for bits that are stuck on.

[Peter Kilmister]

Dust and fungus are perpetual hazards. Change lenses in a bathroom to avoid these two major causes of spots on the sensor.

I also have a "Heath Robinson" solution that @jaapv dislikes. @jaapv knows his way around Leica cameras better than most of us and I accept his criticism of my technique, even though it works well.

Go into a fairly dust free environment, such as a bathroom. Place a vacuum cleaner outside the room but with the extension hose inside the room. Cover the hose with muslin. Get your beautiful assistant to switch on the vacuum cleaner and use its suction to remove the rubbish contained inside the sensor area.

Works every time! It is a near simulation of a clean room technique.

[tjh1023]

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Hi all this has gone farther then I anticipated. to me it looks like dust on the sensor, I am now a proud owner of the M10, sold the 240. I am extremely pleased with the m10 the vf is bigger and brighter my aging eyes love it.

 

Tim

[tjh1023]

On 5/24/2019 at 2:14 AM, islaloha said:

Hi everyone,

I just bought a M240 and after first check it seems there are some marks on the photos. I started to freak out because it reminded me of my old M9P... Tho the sensor looks ok, no visible marks on it.

Here is a photo of the screen after the "dust detection". The marks look quite big, what do you think ? 

 

Thank you for your help 

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

This is from Leica usa in New Jersey, I went there personally and was very impressed. hold the camera with the lens mount facing down  at about a 45 degree angle, and use a rocket blower or some thing similar, blow from top of camera towards the bottom, there is actually a dust collector there. If you really need to clean it more the Leica guys use photographic solutions eclipse cleaner, I got pec pads to use with this (they have good reviews).