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wayn0i
24-08-2015, 10:30pm
So I keep seeing these dark spots on my longer exposure images, but only on long exposures? Ive had a look at the sensor and can't see any dust? Ive heard about shutter oil splatters but I don't really know the difference? Its easy to fix in PP but just time consuming and I'd rather not have to, any ideas

farmmax
24-08-2015, 10:52pm
The little spots in the sky to the left look like dust. You may have to clean the sensor.

mpb
24-08-2015, 10:53pm
Could be.
Have you tested against a bright plain background (say a clear sky) with small aperture, say f22? If it is dirt on the sensor it should show up in the same spots on each shot.
Its easy to clean the sensor and with some care and common sense relatively safe.

Mary Anne
24-08-2015, 11:09pm
I am another one who has been cleaning sensors on my cameras for years.
Plenty of Threads on here type Sensor Clean into Advance Search top of page on the right.. Lots to read there.

bricat
25-08-2015, 7:51am
If you are like me a bit unless it is straight forward I would rather pay and have it done. I look at it as to what damage I can cause should I be too heavy handed, unsteady or how exacting the task is. Compare this to the cost of a clean at the camera shop?? But if it was going to cost $200.00 I might try it myself. cheers Brian

Gazza
25-08-2015, 8:34am
Time for a clean I suspect ... there's a lot of cleanup work when ya look closer.

I've only circled a few, but you get the idea
119444

arthurking83
25-08-2015, 8:42am
If you are like me a bit unless it is straight forward I would rather pay and have it done. I look at it as to what damage I can cause should I be too heavy handed, unsteady or how exacting the task is......

While it's always possible to be too heavy handed or inexact with any type of work .. I believe that most people are sensible enough not to stuff it up.

That is, in the back of you're mind you have this understanding that the item you're dealing with, is a bit delicate. You're not going to approach it with the attitude that this is a well soiled toilet bowl and needs a good scrub.
In fact, the sensor filter stack isn't as delicate as you may think it is, and I've even been a bit 'heavy handed' with it on a few attempts.
Note tho that in this context 'heavy handed' is a relative term, the D800E has been infuriating compared to my other cameras to clean dust off, where it seems that the dust just drags itself across from one side to the other.
What would happen is that I'd start from the side of the sensor that was cleaner, so as to not drag dust across the sensor, but found that after the swipe, the area that was clean at the start was now dusty, and the side of the sensor that was dustier, was now clean.
Getting frustrated a bit with it(and far too many cleaning attempts later), I reckon I became a bit heavy handed by comparison to when I'd have started.
D800E is still looking fine after all that, and it gets dirty quickly and easily too ... which I've been trying to avoid doing again.

The wet cleaning method is easy and a safe enough process .. so one shouldn't fear it as a job to do.

The main thing to consider is that the dust is attracted to the sensor due to static charge(electricity). The longer you leave the dust statically attached to the sensor, the harder it is to clean it off.
The sensor's static charge seems to bake the dust spots more and more over time.

glennb
08-09-2015, 6:56pm
Yeah, looks like dust, to check it, set it f16 or higher if you can for 1 or 2 seconds(till good exposure) at a white pc screen and move the camera around for that 1 or 2 seconds. Then upload onto lightroom like you did to check for the spots. Oil spots will look dark in the middle with a dark ring around the outside. I find my D610 also attracts dust pretty easily too and also have decided to clean it my self as it was needing a clean regularly.

Cage
10-09-2015, 3:05pm
Yep, dust and lots of it.

Do you have your camera set to clean the sensor at start-up and shut down?

You could try a rocket blower and see how that goes but I'm tipping a proper clean is on the cards. I did my D600 and it got rid of the few bits of dust but not the oil spots. I was a bit edgy about doing it but it turned out OK.

Do as suggested above and take some shots of a plain light area (I used a blue sky and a white wall) at f22 and blow them up. If it's oil you'll see some colour around the spot. The oil spots are much darker that the dust spots.

enseth
10-09-2015, 4:26pm
As Arthur said, it's not that difficult. The wipes, both wet & dry, are readily available. I just get them off Ebay. They are not expensive. The other perhaps useful piece of advice I can offer is rather than the rocket blower (the rubber bulb blower thingy") is to go to an electronics shop (Jayco) and get yourself a can of air. I think it's called "Air Duster". I found that this gives a pretty good result for a quick clean, are easier to control and gives a better blast of air than the bulb type blower. One can last for ages.

arthurking83
10-09-2015, 4:37pm
..... The other perhaps useful piece of advice I can offer is rather than the rocket blower (the rubber bulb blower thingy") is to go to an electronics shop (Jayco) and get yourself a can of air. I think it's called "Air Duster". I found that this gives a pretty good result for a quick clean, are easier to control and gives a better blast of air than the bulb type blower. One can last for ages.


I recommend doing this too. The only caveat with canned air is that you must never shake the can before use!
It's probably a natural reaction to shake something like that to try to get more pressure or every last drop of <whatever> out of the container, but if you shake the can of air before use you risk getting propellant onto the area being blasted with air.
The propellant comes out as a white residue and can stick to the surfaces being sprayed.
It's harmless stuff, and if you get it onto the sensor, you definitely then need to do a wet clean to get it off properly.
(been there, done that .. and like I said it's harmless if you accidentally get some on anything.)

What I generally do is to give the can a small blast into thin air to clear the long straw nozzle of any settled dust before use. Then I spray around the mirror box area before getting the camera ready for the clean.
This moves a fair amount of dust out of the mirror box.
From that point on, you're ready to clean the sensor with a quick blast of air. I then close the camera up again after this quick blast, and then do a wet clean.

Very early on .. on my first few attempts to clean a sensor(D70s) .. I also tried the blower bulb type rocket blower device.
Sprayed more dust onto the sensor than was originally on it.

Now the rocket blower is only used to clean loose dust off lenses and filters .. but more so to clean out crud from my (PC)keyboards.