Dust spots and mirrorless cameras go together like a Velcro fastening. One of the main downsides of the mirrorless camera system is the number of dust spots that the sensor attracts.
Last week, I was in a field in Tuscany taking a picture of sunflowers and mountains against a perfect azure sky. It was hot, and there was a warm breeze blowing around me. It was an almost ideal situation. I say “almost” because it was the warm breeze that I would later discover would ruin my image.
The image I was after was a bit of a cliché, but I knew that it would be suitable for social media and would be suited to stock image websites. The colours are bright, saturated and there would be enough room in the blue sky for a designer to add text if needed.
I only had one camera body with me (a Sony a7iii) and two lenses (a 16-35mm and a 70-200mm). I wanted to compress the mountain in the background to reduce its apparent distance, so I swapped out my 16-35mm lens for the 70-200mm lens. That’s where it all went wrong.
The choice of lens was correct, and it was necessary for me to swap the lenses over. However, it was wrong to swap out the lenses in the middle of the field while a warm breeze was blowing. I had already taken some shots of the sunflowers with the 16-35mm lens before deciding upon the photograph above. Taking these earlier shots meant that the camera’s sensor was now warm. In fact, it was probably scorching given that the air temperature was already 37C before I started taking photos. So, swapping out a lens in a field where pollen was being whipped around by a warm breeze was an oversight. Despite being careful and ensuring that I kept the camera body pointed downwards, enough dust to fill a Dyson managed to find its way into my camera and weld itself onto the hot sensor. All without me realising it.
Even as I reviewed the image, and subsequent photos, on the LCD screen, the dust bag was invisible to my old and knackered eyes. It wasn’t until I got home and viewed the image on my monitor that I realised I had 10,000,000 dust spots all over the perfect azure sky. Time for Photoshop and coffee. A full 15 minutes later and most of the dust spots had been removed. The dust spots weren’t removed well enough for me to upload the image to any stock website, but it was good enough for social media. Visit our Instagram page to see the repaired photo.
Conclusion
This is an easy one to conclude – don’t change lenses on a mirrorless camera in a field filled with summer pollen when there is a breeze blowing. Mirrorless cameras do not have a mirror in front of the sensor. So, as you remove the lens, the sensor is exposed to the millions of pollen particles blowing and spiralling in the breeze. Each and every one of those pollen particles will head straight for your camera’s sensor, and the heat of the sensor will ensure they get welded in place.
Dust spots and mirrorless cameras can be a chore and you will definitely need to learn how to clean your sensor.
Please can you give a lesson in how-to clean a mirrorless sensor please. I’ve no idea where to start. Thanks Sue
Please can you give a lesson in how-to clean a mirrorless sensor please. I have no idea where to start. Thanks.
you went with the A7iii then, how are you getting on with it?
Very interesting article and one I have not seen covered anywhere else. I have doubted my decision to start in photography with a mirrored DSLR. This helps to cement my decision. Even tho I know mirrorless will eventually reign supreme.
I wouldn’t worry about dust spots too much Douglas. Sensors are far easier to clean than many would have you believe. I have no doubt that any camera, whether it was mirror less or DSLR, would gather sensor spots in these conditions. I remember spending time cleaning my Nikon sensor after windy days out. Especially in the summer months.
Love it, Alistair. The hype is true.
Ah don’t say that! 😉 I really like my pentax, but some things about the A7iii (focusing mainly!) are really appealing!