Dirt or defect on the sensor?

[wjh31]

Ive just noticed a spot on my images. Ive attatched an image to demonstate the problem (far left, just above centre), picture has been heavily processed to emphasise the spot as its quite subtle. I only just noticed it, but looking back its been in pictures for atleast 2 months. The spot remains with either of my lenses, so i assume its something on the sensor, so is it dirt or a defect? And what's the best way to resolve it once it's been identified?

[Dave Humphries]

Hi Will,

So we shouldn't worry about the "fungus" and bigger, blurrier spots on the right then?

Since I know the word arctic always comes up in these queries sooner or later, I did a search on *arctic* which turned up these threads;
Help needed cleaning sensor on Canon 30D
Camera Bag and sensor cleaning products/solutions
Advice for dust on camera sensor
Arctic Butterfly Sensor/mirror cleaning kit / brush

Hope the above help, fortunately for me, I have no personal experience, but it looks quite sharp edged, possible a drip mark rather than a grain of crud.

I'm sure someone else will be along soon with something more relevant to your particular blob.
For example how to get the mirror locked up so you can look inside and see if it is visible on the sensor surface. (Need to be careful not to get more inside when doing this though)

Cheers,

[john w revie]

It's dust it is a common problem with slr cameras
try removing it with a puffer "do not breath onto your sensor" as this will leave spots.
john

[Amberglass]

If you google about camera sensor cleaning, you will find a myriad of suggestions and recommendations. I recommend using the "dry method" of cleaning the sensor and interior by use of rocket bulb blower and soft acrylic brush.

To check for sensor dust:

1. Set your aperture to the smallest that it will go on your particular lens.
2. Take a photo of the following choices of sky, hold up a white piece of paper to a light source, or bright interior wall.
3. Open the image on your image browser and you see how dirty your sensor is.
4. After cleaning, repeat image steps to see how clean the sensor is.

Cleaning method for sensor, focusing screen, filters, and lenses that I use and steps:

http://www.youtube.com/watch?v=ZRo7pJRkUhs
http://www.youtube.com/watch?v=Auuis...eature=channel
http://www.youtube.com/watch?v=YiyfkrPXiPs
http://www.youtube.com/watch?v=03EVT8igX1Q

I am not a fan of using sensor brushes, "wet method" (aka solutions), or use of adhesive cleaning because it could leave residue or damage the low pass filter covering the sensor. Oil from the mirror mechanism can get onto the sensor which you will end up "smearing" across the sensor while using these methods. The camera will then have to be sent in for service.

For really stubborn dust flecks, I use the Firefly cleaning system. It's very pricey but very worthwhile in my opinion if you need to clean your sensor a lot. You should clean your sensor at least once a week, or the night before your shoot.

http://www.youtube.com/watch?v=_3PM1ebJw1U

[arith]

The only thing I noticed about the 'dust' that may or may not be of interest is it's size and that it appears to be a perfect disc.

[wjh31]

Ok thanks. Cleaning i can figure out, i guess ill just have to get a blower and hope that's enough. I just wanted to make sure it was dirt rather than defective.

Edit: I just took a shot with the aperture shrunk down, and can see clearly the spec of dust. A blower shall be added to the shopping list!

[Amberglass]

Ok thanks. Cleaning i can figure out, i guess ill just have to get a blower and hope that's enough. I just wanted to make sure it was dirt rather than defective.

Edit: I just took a shot with the aperture shrunk down, and can see clearly the spec of dust. A blower shall be added to the shopping list!

Recommends a medium size rocket blower. Blowers by Giottos have filters on the intake end which prevents dust from being blown back on. Make sure that your battery are fully charged prior to cleaning. Do not set up camera up for Bulb mode for cleaning because the sensor will be active and will collect more dust.

http://www.bhphotovideo.com/c/produc...r_Blower_.html

[wjh31]

Since the subject is in mind, back when i was using compact cameras, i would get similar spots on images, if i wanted to revive them to pass on without a spot, is it possible to clean such spots from compacts?

[Amberglass]

Since the subject is in mind, back when i was using compact cameras, i would get similar spots on images, if i wanted to revive them to pass on without a spot, is it possible to clean such spots from compacts?

The dust spots would be more from the front glass element than actually the internal sensor. But yes, use a rocket blower first then apply a couple drops of alcohol on a micro clothe to clean the lens. Allow to dry and then blow off again before shutting off camera.

[wjh31]

The dust spots would be more from the front glass element than actually the internal sensor. But yes, use a rocket blower first then apply a couple drops of alcohol on a micro clothe to clean the lens. Allow to dry and then blow off again before shutting off camera.

I thought id checked and wiped down the front element but ill look again. Could a drop have dislodged a speck of dust onto the sensor maybe? Thanks

[Amberglass]

I thought id checked and wiped down the front element but ill look again. Could a drop have dislodged a speck of dust onto the sensor maybe? Thanks

Mostly likely you have a "dead pixel" on your sensor. You can try turning the camera off, taking the battery out and memory card out, and let it sit there 15 mins. Then marking sure you have a full charged battery, reload everything and turn it back on. Hopefully resetting the camera and rebooting the sensor to energize the dead pixel.

I'm talking about bridge cameras and P&Ss where the lens can not be switched out. The unit themselves are sealed, but yes, dust can get inside if the seals failed. The only other suggestion I would recommend is sending the camera in for service before passing it on.

See how much it costs before you send it in, because if it's an older P&S, a new one may be cheaper to get than having the old one serviced. Oh yeah, I hear you (sighs). I had to make a similar decision for my niece.