# Camera Sensor Cleaning Trainer How dust lands on a camera sensor, how to tell sensor spots from lens spots, and how to blow the sensor clean safely, with no contact\. By kbbkirl Topic: Computing, AI & Electronics [Open the interactive Jig](https://ask.jig.com/j/hSCaZvFuK9Wf) ## Transcript ### 1. Meet the camera This camera has its lens off, ready for a look inside\. Deep in the opening sits the image sensor, the chip that captures every photo\. You will learn how it gets dusty and how to clean it safely, without ever touching it\. Drag to turn the camera, and pinch or scroll to zoom\. This trainer teaches safe habits\. It is not a professional certification\. ### 2. The sensor and its cover glass The image sensor is a chip covered in millions of tiny light catchers\. A sealed sheet of glass, called the cover glass or filter, sits just in front of it\. Dust lands on that glass, not on the sensor itself, and casts a small shadow onto your photos\. A full\-frame sensor is about 36 by 24 mm, close to the size of a postage stamp\. ### 3. Where dust spots come from Dust drifts in whenever the lens is off, and moving parts can shed tiny flakes\. In a photo it shows as soft, dark spots\. They look sharpest at narrow apertures, such as f/11 to f/22, and on plain bright scenes like a clear sky\. At a wide aperture such as f/2\.8, the same dust usually blurs away\. ### 4. Sensor or lens? Photograph a plain white wall or clear sky at about f/11\. Then turn or change the lens and shoot again\. Spots that stay in exactly the same place are on the cover glass\. Spots that move or vanish are on the lens or a filter\. ### 5. Explore the parts Tap a glowing part on the cut\-away camera, or choose it in the side panel, to learn its name and job\. Each card also says whether you may touch it\. Switch between mirrorless and DSLR to see the parts that differ\. ### 6. DSLR mirror and shutter In a DSLR, a mirror tilted at 45 degrees bounces light up to the viewfinder\. For a photo, or in manual cleaning mode, the mirror flips up and the shutter curtains open to uncover the sensor\. The mirror and curtains are very thin\. Never touch them\. ### 7. Mirrorless stabilisation A mirrorless camera has no mirror, so the shutter and sensor sit close to the opening\. The sensor rides on a floating stabilisation platform, held by magnets, that shifts to cancel hand shake\. A poke can knock it out of line, so keep every tool outside the lens mount\. ### 8. Lens, mount and caps The lens mount is the metal ring that locks the lens on\. Its gold contacts carry signals, so keep them clean and dry\. Fit the body cap whenever no lens is attached, and the rear cap on the lens\. Change lenses quickly, with the opening facing down\. ### 9. Never touch these Never touch the cover glass, shutter curtains or mirror with fingers, brushes or tool tips\. Never use canned air or sprays: the cold propellant can leave marks and the blast can push dirt in\. Avoid blowers with bristles, which can scratch\. Canon and Nikon both warn against sprays and brushes on the sensor\. ### 10. Prepare your workspace Work indoors in a clean, still room, away from fans, draughts and open windows\. Charge the battery fully first, because the camera must not lose power mid\-clean\. Lay out a hand blower, the body cap and a clean mat, and wash and dry your hands\. Verify in the manufacturer's cleaning instructions for the exact camera model\. ### 11. Choose the right tool Pick a tool to see whether it is safe\. A plain rubber hand blower is the first choice\. Canned air and blowers with brushes are on the unsafe list\. Swabs and fluid are only for the last resort, if the manual allows them\. ### 12. When to get professional help Stop and book a service centre if a smudge or oily mark survives the blower, if you see a scratch, or if the shutter or mirror looks bent or loose\. Stop too if the battery ran out during cleaning\. Canon and Nikon recommend their service centres for any contact cleaning\. ### 13. Blower clean: mirrorless First run the camera's built\-in sensor clean, which shakes dust off the glass\. Then use the cleaning mode and hold the camera with its opening facing down\. Give a few firm puffs from a hand blower, keeping the tip outside the lens mount\. Switch off and refit the cap straight away\. Some cameras keep the shutter open only in cleaning mode\. Verify in the manufacturer's cleaning instructions for the exact camera model\. ### 14. Blower clean: DSLR On a DSLR, choose manual cleaning in the menu: the mirror locks up and the shutter opens\. Puff with the camera facing down and the tip outside the mount\. Then switch off, so the shutter closes and the mirror drops\. Fit the lens only once the mirror is fully down\. Canon warns never to switch off or open the battery or card door while still cleaning\. ### 15. Wet clean: last resort If a mark stays after blowing, the safest choice is a service centre\. Where the manual allows wet cleaning, use a fresh swab sized to the sensor, with the recommended fluid\. Make one slow, light pass across the cover glass, then use a new swab\. Never press, scrub or reuse a swab\. General practice, not manufacturer\-endorsed, and it may affect your warranty\. Verify in the manufacturer's cleaning instructions for the exact camera model\. ### 16. Reassemble and test Switch off, check that the mirror is fully down on a DSLR, and refit the lens or body cap\. Take a new test shot of a plain bright surface at about f/11 and view it at full size\. If spots remain, blow gently again or get professional help\. ### 17. Practice: find the part Tap the lens mount on the camera, or choose it in the side panel\. If you are unsure, the side panel shows a hint\. Try again as often as you like\. ### 18. Practice: pick the tool You are about to do a first, non\-contact clean\. Which tool should you pick up? Choose one below and read the feedback\. ### 19. Practice: put steps in order Which order is right for a blower clean? A: charge battery, lens off, cleaning mode, puff facing down, switch off, cap on\. B: lens off, puff facing up, charge battery, cap on\. C: cleaning mode, wipe with a cloth, cap on\. ### 20. Practice: diagnose the spots You change lenses and photograph a white wall again\. The dark spots have moved to new places in the frame\. Where is the dirt? ### 21. Practice: unsafe moment Halfway through a blower clean, the camera beeps for low battery while the blower is near the mount\. What should you do first? ### 22. Assessment: how it works Ten questions, one at a time, mixing parts on the 3D camera, step order and multiple choice\. Your first answer to each question counts\. You need 8 out of 10 to pass, and safety\-critical mistakes are flagged separately\. ### 23. Question 1 of 10 Tap the shutter curtains on the cut\-away camera, or choose them in the side panel\. ### 24. Question 2 of 10 Where does sensor dust actually sit? ### 25. Question 3 of 10 Dark spots stay in exactly the same place after you change lenses\. What is dirty? ### 26. Question 4 of 10 Which tool is safe for a first, non\-contact clean? ### 27. Question 5 of 10 Which order is right for a DSLR blower clean? A: lens off, manual cleaning mode, puff facing down, switch off, mirror down, cap on\. B: lens off, puff, cleaning mode, fit the lens while the mirror is up\. C: switch off, wipe the mirror, cap on\. ### 28. Question 6 of 10 Tap the reflex mirror of the DSLR, or choose it in the side panel\. ### 29. Question 7 of 10 The low\-battery beeper sounds while you are cleaning\. What do you do? ### 30. Question 8 of 10 An oily smudge is still there after a few gentle blower cleans\. What next? ### 31. Question 9 of 10 Tap the stabilisation system in the cut\-away mirrorless camera, or choose it in the side panel\. ### 32. Question 10 of 10 On a DSLR, when may you refit the lens after cleaning? ### 33. Your results The side panel shows your score out of 10, your result and any topics to review\. Safety\-critical mistakes are listed on their own\. You can retake the assessment at any time\. ### 34. Sign\-off record After a pass with no safety\-critical errors, confirm the safety checks: battery charged, tools outside the mount, nothing touched, mirror down and cap fitted\. The side panel then shows a record for the learner name, date, camera model, score and assessor signature\. Completing this simulator is not a professional certification\.