Originally posted by Doundounba Hi all. Please see attached photo from yesterday, shooting outside in very bright conditions - no artistic merit in this shot, but it shows the problem most clearly. This spot is still visible today after asking the camera to do some "Dust Removal" a couple of times, and also with a different lens attached. The spot gets more diffuse at more open apertures (say F/2.8 or 3.5) and is more clearly formed around F/8 and onward. (I can even see it on the LCD if I look carefully.) The camera is an almost new K-01 with latest firmware.
Do I already need to learn how to clean the sensor or is there possibly a problem/malfunction with the sensor? Or am I missing anything?
Thanks for any help/suggestions.
My hunch is that it's dust on your sensor.
And it looks like a rather large "hairy" piece of dust at that!
I also know a lot of folks here have recommended using a "Rocket Blower" to remove dust. However, I've found that approach simply moves the dust around inside the camera...and it may even blow dust into other places where it will be even MORE of an irritant...such as between a pentaprism and a focusing screen.
Over the years, I've tried many different so-called "solutions" for sensor dust removal and I think I have
finally found one that works simply, quickly and effectively.
These days, I regularly remove dust from the sensors on all of my DSLRs using a thing called an
Arctic Butterfly. Indeed, I've learned that, compared to the cost (and hassle) of having a camera shop do it, along with my penchant for swapping lenses all the time...the thing paid for itself the
very first time I used it.
Unfortunately, as the rubber seals, gaskets and pieces of foam in these cameras age over time (along with the continual movement of air in and out of the camera with the use of zoom lenses) one can't help but have such stuff sucked into (or around) inside your camera, some of which eventually winds up on the sensor. I have also learned that this can happen even if you don't swap lenses all the time. For example, some dust showed up on the sensor of my brand new K-20 a while back even though up to that point I had
never swapped lenses on it!
The bottom line here is that dust WILL get onto your camera's sensor sooner or later....
regardless of how careful you are to keep it out.
I've also learned that the "sensor shake" feature on K-20D-era (and earlier) Pentax cameras may have been a great Madison Avenue selling point at the time, but is nigh on useless in practice. It simply doesn't work.
However, I now understand the newer Pentax cameras have an "ultrasonic" feature that shakes the dust off the sensor....and into a "catcher" of some sort. Call me a purist, but, just with the use of Rocket Blowers, this feature
still only moves the dust around inside the camera rather than getting it out completely!
The Butterfly thingie works by spinning the inserted brush (which gives it a static charge) outside the camera. Then, once you've removed the lens and activated your "mirror up" feature on the camera, as you pass the brush (gently) over the sensor and the dust is sucked up onto the brush because it's statically charged. You then spin the brush again (outside the camera). This gets rid of the collected dust off the brush as well as re-charging it. You can then repeat the process if you like. Usually, one or two spins and passes over the sensor are enough to get rid of the pesky stuff.
And, if you have any concerns about scratching your sensor with the brush...relax. The Arctic Butterfly brush is specifically manufactured for sensor cleaning and contains some VERY fine bristles, so there should be no worries about scratching your sensor with it.
The Arctic Butterfly is marketed by an outfit out in Canmore, Alberta, but is available in the USA via Amazon and most of the big US camera dealers such as B&H as well as Adorama. The outfit's name is Visible Dust. I also own their lighted Sensor Loupe that lights up the sensor to show you exactly where the dust is on the sensor before you clean it (and to show you when it's gone!).
Visible Dust also markets a line of liquid cleaners specifically manufactured to get rid of such things as oil smears and other more stubborn "goop" from sensors. But, as I said, most the time, it's simply a dust issue and it usually takes less than a minute or two (with a few swipes of my Arctic Butterfly) to get rid of it.
Here's a link to a You Tube Video that shows you how the Arctic Butterfly works:
Now if this all sounds like a paid advertisement for Visible Dust...it isn't. I'm simply a
very satisfied user of their products. And while their products may appear a bit pricey, the Arctic Butterfly is a really great product that is simple to use, VERY effective and a
whole lot less costly over time than having a camera shop continually remove the dust for you.
Needless to say, my Arctic Butterfly and Sensor Loupe now occupy a special place in my camera bag and go with me everywhere I go.