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Showing posts with the label scanning

Vibration-Proof Scanning Setup: Is Yours Up to the Task?

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As I look at pictures of camera-scanning setups, I can't help but have a persistent worry: what if all of these weights on long poles are just pendulums waiting for a bump to start swinging. Of course, the manufacturers claim that their stands are as steady as rock, as stable as an Egyptian pyramid, as solid as gold bullions. However, I am not fully convinced. If I were to tell you that a camera on such a stand moving just 1/10 the thickness of a human hair during exposure would result in a loss of half the resolution, would you be concerned? So, in this article, I'll present my arguments and show you how to check and possibly secure your own scanning setup against vibrations. Blurring the edges Certainly, let's start from the basics and define what is meant by "blur".  Blurring on a camera occurs as a result of movement of the camera, subject, or both. Motion blur specifically refers to the streaking or smearing seen in the image due to this movement [1].   On th

Zen and the Art of Camera Scanning

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My article   Zen and the Art of Camera Scanning or The Brief History of Vlads Test Target  is now live on 35mmc.com

Type 120 Positive Test Target PO69

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Here is more details on new Type 120 Positive Test Target PO69. This is exact reversal of the Negative Test Target NG69.   The note from Vlad:  The reasons why I started offering the Positive Test Targets are as follows. Everyone who used negative targets while viewing images in the digital camera have encountered the strong hallo around target's bars and stars. That's because camera sensor averages the brightness of the scene and sets certain exposure values. Given that most of the image is almost black (in case of negative) the camera brings brightness up until black areas look gray. That means that transparent areas with bars and numbers are getting overexposed (they basically end up being in Zone 0) . That forces operator to manually step down camera to avoid those overexposures .  Still the halos remain the issue and interfere with the focusing. With positive targets the i ssue will go away - the sensor reads mostly transparent areas, the averaging will lead to whites bei