Does sensor need cleaning?

[richfx]

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I've taken appr. 2,500 photos since receiving my M9 in January. I noticed several very small dark spots along the side of images after test shots of a bright sky with several lenses stopped all the way down weeks ago, but I haven't see any spots in other shots since, even those stopped down. Today out of curiosity I visually examined the sensor (after using a rocket air blower) - no loupe or magnifying glass, but under very good light, including an LED headlamp (which didn't seem to help). It looked spotless. My question is whether one needs magnification in examining and, when required, cleaning the M9's sensor in order to see and safely remove dirt, dust, oil, etc.

Thanks,

Rich

[msk2193]

Rich,

 

Put a lens on f/11-16 or so, out of focus and point into a bright light source then take a photo. If there are spots on the sensor they will show when viewing the file on screen. Remember the spots will be on the opposite side of the location of the image!

[k-hawinkler]

This reference may be of interest http://www.l-camera-forum.com/leica-forum/leica-m9-forum/114998-m9-ultimate-sensor-cleaning-device.html

[Ario Arioldi]

f you cannot see spots on your pics there is no need to clean the sensor.

Cheers,

Ario

[RSL]

Rich,

 

Put a lens on f/11-16 or so, out of focus and point into a bright light source then take a photo. If there are spots on the sensor they will show when viewing the file on screen. Remember the spots will be on the opposite side of the location of the image!

 

If you see a spot on the upper left side of a test image, when you look at the sensor from the front of the camera the debris that made the spot will be on the lower left side of the sensor. For a serious check, stop down to f/16, crank the focus down to the nearest point (defocus), and shoot a bright blue sky. Bring the result into Photoshop and use auto levels. If there's dirt there, you're going to see it. Looking at the sensor with the naked eye isn't going to tell you anything worthwhile. Even examining the sensor with a loupe won''t necessarily show all the crud.

 

Ario's essentially correct, but with one caveat: If you've been shooting at, say f/4 with no problems and you suddenly switch to f/16, you may see dirt you never saw before. It's worth testing from time to time so you know what's there.

[Ario Arioldi]

If you see a spot on the upper left side of a test image, when you look at the sensor from the front of the camera the debris that made the spot will be on the lower left side of the sensor. For a serious check, stop down to f/16, crank the focus down to the nearest point (defocus), and shoot a bright blue sky. Bring the result into Photoshop and use auto levels. If there's dirt there, you're going to see it. Looking at the sensor with the naked eye isn't going to tell you anything worthwhile. Even examining the sensor with a loupe won''t necessarily show all the crud.

 

Ario's essentially correct, but with one caveat: If you've been shooting at, say f/4 with no problems and you suddenly switch to f/16, you may see dirt you never saw before. It's worth testing from time to time so you know what's there.

This is true, but then This is the case in which you see spots on the real life pics.

BTW, with M lens it is not a reccomended practice to close down to F/16, where diffraction will negagatively affect the quality.

Cheers,

Ario

[RSL]

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This is true, but then This is the case in which you see spots on the real life pics.

BTW, with M lens it is not a reccomended practice to close down to F/16, where diffraction will negagatively affect the quality.

Cheers,

Ario

 

True, Ario, but when you're shooting a blank sky with a defocussed lens, sharpness in the sky isn't exactly your first priority. What you want sharp is the crud on the sensor. In this case the smaller the hole the sharper the crud.

[richfx]

Thank you all. I reshot bright sky today with my 50mm Summilux ASPH at f/16 completely defocused. Here are the results. There is a small spot at top left corner and seven or eight close to right edge, almost all from midpoint down (I know the actual spots on sensor are 180 degrees reversed). To me, these appear very minor, and they don't seem any different from those taken appr. 1,000 actuations ago. Do they warrant a dry cleaning with DLC SensorVu Cleaner now?

Rich

[digitalfx]

That's your call...personally I would wait.

 

Can you even see these in real prints??

[RSL]

Rich, I agree with digitalfix. Have you tried blowing the crud off? Try a couple puffs at the middle of the right side of your sensor as you look at it from the front of the camera. If that doesn't solve the problem, I'd ignore it for now -- unless you're planning to do a lot of shooting at f/16.

[250swb]

If you've already used a Rocket Blower Rich then if you didn't have much dust you will now. Its not very good at removing dust, and if you haven't cleaned your sensor yet you will most likely have oil on it anyway which will require a proper wet clean.

 

There is no time like the present to do a clean. Its all very well listening to the mantra that "with M lens it is not a recomended practice to close down to F/16", but there are balances to be made and if you do need the increased DOF you should feel free to use f16, and you don't want to be hamstrung by the knowledge that if you do you will show up all that dust. So no, leaving it there because you only shoot wide open isn't good enough ;-)

 

Steve

[Ario Arioldi]

If you've already used a Rocket Blower Rich then if you didn't have much dust you will now. Its not very good at removing dust, and if you haven't cleaned your sensor yet you will most likely have oil on it anyway which will require a proper wet clean.

 

There is no time like the present to do a clean. Its all very well listening to the mantra that "with M lens it is not a recomended practice to close down to F/16", but there are balances to be made and if you do need the increased DOF you should feel free to use f16, and you don't want to be hamstrung by the knowledge that if you do you will show up all that dust. So no, leaving it there because you only shoot wide open isn't good enough ;-)

 

Steve

Steve,

it is not a mantra, its "optics".

Cheers,

Ario

[viramati]

Personally I find the rocket blower usually gets most of the dust off but I always give the chamber a good blowing out before opening the shutter as otherwise you will just be blowing more stuff in. Have also become very wary about using the arctic butterfly as it is really easy to pick up oil from the edges or sides and smear it on the sensor

[250swb]

Steve,

it is not a mantra, its "optics".

Cheers,

Ario

 

Blind obedience to lens charts and the fact that f16 is not as good as f5.6 is not a good excuse to avoid cleaning dust off a sensor. f16 is there to be used if it needs to be used and not ignored because of some slight degradation of the image. It is rare, perhaps impossible, to find a good photograph that solely relies on pixel peeping and ulitmate IQ for its impact.

 

Steve

[Ecar]

Unlikely that these spots would bother you at smaller apertures. I'd just use the clone tool if they are visible - and clean the sensor only when it gets noticeably worse. Just MHO.

[richfx]

Thank you all for your learned advice and suggestions. Think I will hold off for now, as I've read that dry and wet cleanings can exacerbate existing dust, dirt and oil spots and move it all around. Right now, the spots are quite minor and hardly visible. I'll start with a dry clean when appropriate and move onto a wet clean as required.

Rich