Author Topic: Sony a7R III: The Star Eater is No More  (Read 270 times)

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Mike

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Sony a7R III: The Star Eater is No More
« on: Nov 15, 2017, 22:02:20 »
Sony’s latest mirrorless cameras have incredible specs and glowing reviews, but astrophotographers have been complaining about a “star eater” issue in which stars are mistaken for noise and removed from long exposure photos. There’s some good news, though: it looks like the new Sony a7R III doesn’t have the “star eater” problem.

MORE......

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

MarkS

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Re: Sony a7R III: The Star Eater is No More
« Reply #1 on: Nov 16, 2017, 01:13:17 »
Unfortunately the reports give a misleading impression.

My examination of the raw files shows that the A7RIII has exactly the same spatial filtering as the A7RII v4.0

It's true that the stars aren't eaten in that example but that's because they have trailed slightly.  But you can't see the trailing at the scale the files are displayed.

Look at my FAQ on star eater here: http://www.markshelley.co.uk/Astronomy/SonyA7S/sonystareater.html  especially the section titled: Why are many night sky photographers unaffected?

Mark
« Last Edit: Nov 16, 2017, 15:01:16 by MarkS »

MarkS

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Re: Sony a7R III: The Star Eater is No More
« Reply #2 on: Nov 18, 2017, 13:58:43 »
I've written a page on how to recognise the spatial filtering that eats stars:
http://www.markshelley.co.uk/Astronomy/SonyA7S/diagnosingstareater.html

There's also a link to it on the left hand side of my main page:
http://www.markshelley.co.uk/Astronomy

Mark

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JohnP

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Re: Sony a7R III: The Star Eater is No More
« Reply #4 on: Nov 22, 2017, 08:25:21 »
:-( I guess at the end of the day the % of these camera's that Sony sell to astro-photographers is so small compared to the overall sales they don't give 'a teaspoon of Apple sauce' about it.... it would be so simple for them to remove the offending code or even add a line of code so there is a menu choice to switch the hot pixel reduction on or OFF... Would be so good if someone with the skills could 'hack' it...

Ps. I removed my offending code.... 😁
« Last Edit: Nov 23, 2017, 21:41:00 by JohnP »

Carole

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Re: Sony a7R III: The Star Eater is No More
« Reply #5 on: Nov 22, 2017, 10:35:04 »
Some right arrogant and ignorant replies on that article:

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If these alleged "serious" astrophotgraphers *really* cared about "single-pixel" stars and noise discrimination, they'd be using an equatorial mount, as well as stacking software and dark field removal algorithms, stacking multiple 3.2-sec exposures that are not affected by LENR.
Taking multiple exposures in quick succession is easy to do with mirrorless cameras that have a fully electronic, vibration-free shutter that doesn't need to be cocked by a motor.

If they don't even use an equatorial mount, then, the resulting star trails will necessarily be longer in spatial extent than a single pixel, and thus unlikely to be affected by a LENR that targets single hot pixels.

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As I said, nothing prevents these "astrophotographers" obsessing about "single-pixel" stars from stacking multiple 3.2-sec exposures, except their own laziness or incompetence.

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Too many stars as it is. Looks like a bunch of noise.

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If you're serious about shooting stars -you don't use a camera like a Sony, or Canon. You use a tool designed for the job.

Fay

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Re: Sony a7R III: The Star Eater is No More
« Reply #6 on: Nov 22, 2017, 19:01:38 »
we need our champion, Mark, to put him right!!   
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

MarkS

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Re: Sony a7R III: The Star Eater is No More
« Reply #7 on: Nov 24, 2017, 12:13:28 »
Yes there are plenty of ignorant and arrogant comments and trolling.   To be fair though, Sony's latest firmware means that the average user taking panoramic Milky Way shots on a tripod wont notice problems.
Ironically it affects those who invest the most in good equipment (sharp lenses and trackers) and expect to get the very best out of their camera.

Mark

Mike

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Re: Sony a7R III: The Star Eater is No More
« Reply #8 on: Nov 27, 2017, 08:53:54 »
This is so stupid. It would be literally a few extra lines of code to completely turn off all filtering and allow a pure raw image to be recorded. I am baffled why they will not do this when some other manufacturers have done so with theirs?!
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Apophis

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Re: Sony a7R III: The Star Eater is No More
« Reply #9 on: Nov 27, 2017, 11:24:56 »
Maybe forward this thread to Sony Support?
Roger
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