Hacker News Reader

Comment by SomeHacker44 | Hacker News Reader

Photographers think of "RAW" as the unmodified original data from the image sensor. It is raw in the sense that no further processing has been applied yet to make a human viewable image (or whatever you want to do with it). It would need to be demosaic'd, adjusted for lens distortion, have dynamic range and gamma adjustments, and other things to make a nice image for humans to view.

View on HN

> Photographers think of "RAW" as the unmodified original data from the image sensor. It is raw in the sense that no further processing has been applied yet to make a human viewable image (or whatever you want to do with it). It would need to be demosaic'd, adjusted for lens distortion, have dynamic range and gamma adjustments, and other things to make a nice image for humans to view.

Yes, but even besides that, image sensors only capture a part of the spectrum.

Is a combination image from 3 different spectrums (let's say UV/X-Ray/Visible) raw or no? Is it less or more raw than individual images?

That's what my comment was about.

The “raw” data in so-called “raw” image formats in not unprocessed data from the image sensor. The camera will already have done processing on the data, it’s just not fully processed.

If it was indeed raw data off the sensor, you’d see all kinds of “bad” things such as dead pixels. And camera vendors (obviously?) don’t want you to see that.

> The “raw” data in so-called “raw” image formats in not unprocessed data from the image sensor.

RAW images are completely un-demosaiced and otherwise unprocessed sensor data, dead or stuck pixels and all. It's the job of the RAW converter (whether performed in-camera or post-capture) to hide those in the conversion to a standard color space.

Manufacturers are now blurring the meaning of RAW to be closer to what you imagine. For example, Apple's ProRAW images are demosaiced and heavily processed.

Reply on news.ycombinator.com