Dust removal by correlation in image set without reference

pierre5018 · September 10, 2020, 2:11am

suggestion: Photolab compares pictures in a user-selected set of images. The feature detects dust by correlation, where dust is the signal to be found and each actual image is considered as noise. This process could find the noise without a reference image.

This would be followed by batch cleaning of the whole set.

Ralf_Brinkmann · September 11, 2020, 10:50am

Good idea!

Perfrode · December 8, 2020, 10:37am

Spot on suggestion! I have also addressed this in a new post. We need to keep the pressure on the DXO team so we get what we want, n’est pas?! Oui oui!

Perfrode · December 8, 2020, 9:49am

( has this been suggested before, or is there already such a function… )

PL4 should have an Automatic Spot Detect and Removal tool.

Sensor spots are not uncommon. To manually remove these spots takes a long time, and is almost impossible to perfect. You always miss a spot… If DXO looks at two or more different pictures taken with the same camera that has been taken at the almost same time, it should be possible to detect common pixels / spots. These common pixels / spots are most likely sensor spots. Have them highlighted, flashing red or a contrast color to whatever is in the background, ask “remove all spots”? Or you can click on the ones you want to remove, or keep. It should also be possible to take a picture of a white / neutral paper to use as “spot reference”. PL4 can use this to speed up and perfect the process of detecting spots, and what are spots and maybe not. PL4 should also be able to detect spots without comparing photos, by analyzing each picture and detect what is most likely a spot. Maybe this is difficult.

Such a tool will also tell the user when it is time to clean the sensor. PL4 may suggest when it is time. When the sensor has been cleaned, take a picture of a white paper again. PL4 will then tell you if the cleaning is good or not. PL4 can also keep track of when more spots has collected on the sensor, and give you a “heads up”. “Sensor spot detected”, “New sensor spot detected”, flashing on the photo. A green, yellow, red sensor status. Meaning: Green, “toutes est bon”, your sensor is basically clean, and PL4 can easily detect and remove spots, spotlessly. “Yellow”, PL is using a lot of resources to detect spots. Some spots may not be detected and some may not be removed properly, “Sensor cleaning recommended”. “Red”, PL4 is unable to detect most spots, what are spots and what not, spots detected are not removed effectively. ie, “Clean your camera NOW, and next time, don’t change lenses in a sand-storm…, Sil vous plait!”

pierre5018 · December 8, 2020, 10:24am