I’ve recently started noticing some dust specks in the photos from my DSLR which are starting to bug me. In fact I’ve never actually seen my camera’s sensor completely clean as they often come preloaded with dust from the factory.
I’ve made some attempts at cleaning the sensor (it’s actually the low-pass filter infront of the sensor, but I’m just gonna call the whole thing ‘the sensor’) but haven’t had much luck. Anyone who has tried poking around in a $1000+ camera with various cleaning implements will know how stressful this process can be.
I’m not going into the detail of cleaning a sensor, and I’m going to pretend you already know all the risks and considerations to make when touching the sensor with ‘anything’. No; today I’m going to talk about this nifty goo I found called Sensor Film. I struggled to find many reviews of this stuff while I was researching it but found it intriguing enough to give it a go. Hopefully my experience here will help others.
Sensor film is a polymer that you paint onto the sensor with a small soft brush. Once it has dried you peel it off and hopefully take all the dust on your sensor with it. The advantage is that you never put any pressure on the sensor, and never rub anything against it so the risk of scratching is negligible. You also have the chance to clean out the mirror chamber with a blower/vacuum while the sensor is protected under the polymer.
The consistency is much like honey and it is very easy to apply it to the sensor. It does have a tendency to draw out long ‘tails’ (just like real honey) that you need to prevent before you move the brush near the camera. If you don’t, you’ll end up leaving little spider webs around your mirror chamber which is probably a bad thing. It’s well behaved on the sensor and goes where you tell it to, but it’s still a delicate operation to cover the sensor without getting too close to the edge. I have a Canon 600D which has a fluoride coated low-pass filter, so naturally I’m using the fluoride variant of Sensor Film. The film was also nice enough to even itself out after sitting for minute, so I only needed to make sure there was enough goo and not worry too much about how evenly I spread it.
After the sensor is covered you have to let it dry which may take up to 3 hours according to the manufacturer. They also recommend you leave the shutter open the whole time so make sure you have a fresh battery. They never actually state how to tell if the film has dried, but I found mine dry to the touch after about an hour. Also about the closest you ever want you finger to get to the sensor :P.
To remove the film, you need to attach a small paper tab. There is a piece of paper for this included with the Sensor Film; I don’t know what’s special about it, but if you keep it with the bottle of goo there should be enough for all your cleaning needs. Cutting the tab is easy, but be sure to make it an appropriate length. It’s very easy to over estimate the length you need which will lead you to make a mess of attaching it. The tab is simply glued to the film with a small amount of Sensor Film.
My first attempt at this tab failed. The paper de-laminated as I tried to pull the film off the sensor. I suspect it may not have been close enough to the edge of the film, or the strip of paper I used was too thin. After cutting another strip and a very stressful 30 minute wait for it to dry again I managed to peel the film off without an issue. The force required was quite reasonable, and certainly didn’t feel like there was a risk of damaging the filter.
The results were impressive. Almost all the specks, including the largest ones were gone. There were still a few remaining that were not present in the before shot. These may have landed in the time it took me to attach a lens and close the shutter. There was one large blob in the corner, which on close inspection was a small piece of lint. It wouldn’t budge with a gentle breeze so I made the foolish decision to move it with the brush. This left a comically large smear on the sensor and caused my palm to connect with my face.
After staring at the smear in a new test shot, I decided to start the process again. This would allow me to maybe clear the rest of those specks, test Sensor Film on a nasty smear and see how repeatable the process was. With the justification out of the way, I set about painting my sensor again (after swapping batteries of course).
This time I tried for a smoother coating, avoiding or removing air bubbles as I could. The practice helped and I was much quicker at coating the sensor. It was fairly warm in the space I was working so the film dried quickly. I would’ve finished under an hour, but I had the same issue with the first paper tab delaminating.
After peeling this one off and taking a test shot all I could think was WTF?! The sensor was pretty much perfect except for one giant chunk just off center. There were also a couple of very minor spots that were consistent across all my test shots, and obviously impervious to Sensor Film. The smear from last time had mercifully vanished without a trace.
The big chunk prompted a third attempt. This time I decided to lay the film on pretty thick. This is the best way to avoid any voids made by brush strokes or bubbles. The film doesn’t seem flow out of the area you apply it to, but does smooth itself out pretty well. Getting the edges thick takes a bit of technique. The process is more about gently pushing the film into the areas you want it rather than brushing it on to the surface.
After peeling this third film off (first time!) and taking a test shot I was relieved to finally have a clean sensor. There was still one stubborn spot, but it was not significant enough to worry about.
In conclusion I’m going to be pretty generous to Sensor Film. While it takes more practice than advertised it did a remarkable job cleaning my sensor. I’m sure the number of applications can be minimised by taking more care and having a little more experience with how the stuff works. Most other methods of sensor cleaning I’m aware of also require multiple attempts; the big difference with Sensor Film is how stress free each attempt is. Even after painting my sensor three times I never felt like I may have done any damage, at least after I successfully peeled the first film off :P.
I would recommend Sensor Film. It’s just as tedious and frustrating as any other method out there, but it does keep the heart rate to a minimum while cleaning. When you’re done, the results are as good as you can expect. Just take your time and apply it and make a nice thick film.
And for those who are curious: here is what the world looks like through a layer of Sensor Film.
