iStockphoto - Stock Photography Training Manual

4.0 Quality Standards

4.10 Sensor Spots & Hot Pixels

Sensor spots happen when various tiny bits of dirt and dust enter your camera body and find their way to the sensor. If you change your lenses frequently or work in dusty environments, manual sensor cleaning becomes a routine.

Skies and frame corners are particularly vulnerable, and the more you close down your lens, the more visible any dust on your sensor becomes. Watch for these spots when you edit your files – they are easy to remove. We don't want to see any dust spots on the images you submit.

Unacceptable:

Hot pixels may show up on an image if the sensor has overheated. This may happen during a long exposure. Sometimes a single pixel in your sensor may become completely dead and won't record any data at all, causing a single dead spot to always appear in the same place in your images. These dead pixels aren't a huge issue – a few of them out of the millions in your sensor will naturally die over the years. Learn where they are and always remember to edit them out before you upload.

Unacceptable:

Tips:

  • Clean dust off your sensor regularly, as often as your workflow, location, and environment require. Some people do it once a week, some once a year. Some people do it themselves, some give their camera to a local shop. Many cameras include a sensor mapping feature, that lets you teach the camera to find new dust spots and hide them, requiring less frequent cleaning.
  • Be very, very careful if you are cleaning your sensor yourself. It is possible to damage the AA filter or the sensor itself.
  • Review your images carefully at 100% corner to corner, especially with big depth of field shots. Dust spots and hot pixels are easy to find and remove – there really is no excuse for having them.
  • For “hot and noisy” pixels caused by long exposures, carefully spot-use a de-noise application, either in-camera or during editing.
  • For long exposures, try your camera's 'long exposure' or 'dark frame subtraction' noise reduction. This should remove almost all noise with no reduction in quality. The downside is it will double your exposure time.

Previous | Next

Contents

1.0 iStockphoto's Standards

2.0 Account Information

3.0 Image Requirements

4.0 Quality Standards

5.0 Film Scans

6.0 Title, Description & Keywords

7.0 Legal Requirements

8.0 Model & Property Releases

9.0 Editorial Use Only Images

10.0 Prohibited Uses

FAQs

Not a member?Join
Buy iStock Credits