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Nikon makes firmware for astronauts to block cosmic rays in photos

petapixel.com

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Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#31

Post by dekhn »

davidmurdoch wrote: post #25
malfist wrote: post #19

Earlier quoted context omitted.

Dark frame subtraction cannot remove cosmic rays. It removes things the camera sees in the dark at the time of dark frame capture. This is things like dead pixels, hot pixels and amp glow. If a cosmic ray was removed by a dark frame, two cosmic rays would have had to happen, one during dark frame and one during the actual capture. They'd have had to be the same intensity and hit the same pixels. This is probably neve…

What's the freezer thing about?

there are several sources of pixel noise, some of which are temperature dependent. Making the sensor cold reduces the temperature-dependent pixel noise background.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#32

Post by riversflow »

yakubin wrote: post #28
lakpan wrote: post #23

Earlier quoted context omitted.

So, wait. The camera can fix dead pixels but only does so once a month? Dead pixels are dead easy to detect by the sensor, why don’t they do it immediately? Way to ruin a bunch of photos between cleanups…

Every photo taken shortens the life of a sensor.

To add to this, with those particular cameras(it’s the frame I shoot on), you’re encouraged by the form factor and ergonomics to turn them off when idle to get the most out of the smallish battery, they boot in like 1s. A battery is good for ~350 shutter pulls, I don’t want to use one of those every time I think about taking a picture.

Also, a dead pixel is not a ruined photo, it’s a minor inconvenience in editing at worst. And every photo I take on a FF is getting edited, the gorgeous RAW output is what I’m there for.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#34

Post by sudosysgen »

lakpan wrote: post #23
sudosysgen wrote: post #3

Earlier quoted context omitted.

If you use a Sony A7 series camera, every month, the camera will take a picture upon shutting it off, which it uses to remove dead pixels/hot pixels - you can hear it, actually. If ever you have a pixel die or get stuck, you can also manually set the date a couple months ahead and turn it off - it will most likely be fixed when it turns back on.

So, wait. The camera can fix dead pixels but only does so once a month? Dead pixels are dead easy to detect by the sensor, why don’t they do it immediately? Way to ruin a bunch of photos between cleanups…

Sometime dead pixels are not a fully on-off affair, so taking a dark frame is really needed, and you don't want to be doing that too often because then the camera is not usable then.

It sucks, but it is what it is, and it's not too difficult to batch remove dead pixels - if you even notice them.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#35

Post by sudosysgen »

yakubin wrote: post #29
sudosysgen wrote: post #3

Earlier quoted context omitted.

If you use a Sony A7 series camera, every month, the camera will take a picture upon shutting it off, which it uses to remove dead pixels/hot pixels - you can hear it, actually. If ever you have a pixel die or get stuck, you can also manually set the date a couple months ahead and turn it off - it will most likely be fixed when it turns back on.

Does it affect RAW photos or only JPEGs?

It affects RAW photos, too. You also have similar artifacts sometime from on-sensor phase detection pixels.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#36

Post by sudosysgen »

yakubin wrote: post #28
lakpan wrote: post #23

Earlier quoted context omitted.

So, wait. The camera can fix dead pixels but only does so once a month? Dead pixels are dead easy to detect by the sensor, why don’t they do it immediately? Way to ruin a bunch of photos between cleanups…

Every photo taken shortens the life of a sensor.

That's not really true, it's only a problem for the shutter. The sensor doesn't really break.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#37

Post by sudosysgen »

causi wrote: post #17

I wish there was good software for hot pixel removal in normal digital cameras. Sure you can photoshop pictures one by one, but if you have the same set of bad pixels on every shot and need to remove them in batches? Nothing will do that as far as I know.

If you use Lightroom, make a 1 pixel patch around the hot pixels, and then copy/paste the edits. Basically every other image editing software is also going to allow a similar workflow.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#38

Post by yakubin »

sudosysgen wrote: post #36
yakubin wrote: post #28

Earlier quoted context omitted.

Every photo taken shortens the life of a sensor.

That's not really true, it's only a problem for the shutter. The sensor doesn't really break.

You’re right. I misremembered. The term is “shutter life”. Same result though.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#39

Post by wtallis »

yakubin wrote: post #38
sudosysgen wrote: post #36

Earlier quoted context omitted.

That's not really true, it's only a problem for the shutter. The sensor doesn't really break.

You’re right. I misremembered. The term is “shutter life”. Same result though.

Not the same result: we're talking about taking a picture without opening the shutter.

Re: Nikon makes firmware for astronauts to block cosmic rays in photos

#40

Post by [deleted] »

yakubin wrote: post #28
lakpan wrote: post #23

Earlier quoted context omitted.

So, wait. The camera can fix dead pixels but only does so once a month? Dead pixels are dead easy to detect by the sensor, why don’t they do it immediately? Way to ruin a bunch of photos between cleanups…

Every photo taken shortens the life of a sensor.

[deleted]
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