111 replies to this topic

[xonefs]

Thank you Mark. I truly never thought I would see the day when Sony removed this. Exciting times. Now I only wish they would update it in firmware of some of older cameras but not expecting much there. 

 

What program/methodology did you use to create the first graphs analyzing the dark frames? I would like to try replicating it. 

[sharkmelley]

My methodology is not very clever.  I wrote a PixInsight script to dump out all unique pairs of pixel_value & max_neighbour_value to flat files then used a Python script to read in those flat files and plot them. 

[gregbradley]

You are too modest Mark.

 

That is good news about another let model Sony no longer doing star eater.

 

I just updated the firmware of my Sony A7R3 yesterday. I hope to take some images with it and I'll post the result.

 

Greg.

[Whereisclearsky]

Using Sony A6400 with Tamron lens gave me the worst concentring rings I've ever seen, would stay away from Sony lol.

[Digitaliz.se]

I think it has to do with the lens more than it has to do with the camera.

 

/Stefan

 

Using Sony A6400 with Tamron lens gave me the worst concentring rings I've ever seen, would stay away from Sony lol.

[FrankieT]

You are too modest Mark.

 

That is good news about another let model Sony no longer doing star eater.

 

I just updated the firmware of my Sony A7R3 yesterday. I hope to take some images with it and I'll post the result.

 

Greg.

+1

 

It's promising that Sony has listened to critical feed back and seems to have improved their product for astro. I hope that Nikon follows their lead.

[Whereisclearsky]

I think it has to do with the lens more than it has to do with the camera.

 

/Stefan

Sigma lenses gave me rings too, but the one from Tamron was like the ring from hell.

[whwang]

It's the camera, not the lens.

[Digitaliz.se]

Yepp, it's the lens. Some are worse than others.

 

Sigma lenses gave me rings too, but the one from Tamron was like the ring from hell.

 

 

Defintly not. I use several Sony cameras with both lens and telescopes. It's not the camera that causes the rings.... Unless you have activated lens corrections in camera. These can cause issues too.
 

It's the camera, not the lens.

[sharkmelley]

The coloured concentric polygons are generated by in-camera processing. See:
https://www.markshel...d_polygons.html
Sony has even patented the methodology that generates them!

[Digitaliz.se]

So it is the lens after all that causes the camera to missbehave. Just use a telescope, or an lens that has no electronic connections, or a lens that is not supported by the camera. 

 

"Conclusion

For lenses recognised by the camera firmware, the Sony lens corrections are still applied to the raw image data even when lens corrections are disabled in the camera menu. This is potentially a big problem for deep-sky astrophotograpy, causing concentric coloured poygons to appear in the background. The good news is that the lens corrections are not applied for (non-electronic) legacy lenses nor for directly-attached telescopes."

 

 

The coloured concentric polygons are generated by in-camera processing. See:
https://www.markshel...d_polygons.html
Sony has even patented the methodology that generates them!

[whwang]

The logic cannot be simpler than this:

 

If you think it’s the lens, then what you should do is to write to the lens manufacture(s) to ask them to correct the problem.  Good luck to you.

 

I think it’s the camera, so I will use my connection to Sony to urge Sony to correct the problem.  

Edited by whwang, 16 January 2024 - 08:47 AM.

[whwang]

Earlier Mark got a raw file from me and confirmed that there is no detectable damage to the stars (post #18).  That was taken through a lens.  I wanted to double check this with real deep-sky images taken with a good scope.  So I borrowed a A7R5 again from Sony Taiwan.  I was lucky to get some good clear nights last week.  This is the image I got:

 

Other than that the camera is unmodified, I cannot tell the difference between A7R5 and other verified good cameras (e.g., hacked D800, Pentax 645z).  The stars look perfectly normal, sharp, and tight.  Even the photometry (in PI's PCC or SPCC) looks quite fine.  So I think we can now confidently say that there is no longer star eater problem on A7R5.

 

One and half year ago I made some test shots with A1 and A7R4.  Unlike the A7R5 case here, they still showed signs of star eater.  So the change of how Sony cameras deal with hot pixels must be some recent thing.

Edited by whwang, 16 January 2024 - 09:02 AM.

[Digitaliz.se]

i have no problems with star eater as well on any of my Sony cameras.

 

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[whwang]

Good for you.  I mean it.  Not sensitive to problems is actually a bless.  Sometimes I hate myself in the sense that I can't unseen problems after I see them.

 

When I looked at the three images you just showed, I see dark centers in many stars in the left one and the middle one.  I see green stars in the right one.  These are typical symptoms of star eater, and the end results of stacked images would be soft stars and/or a green tint in many stars.  A7R5 does not have any of these, and this is great news for Sony users.  I always hesitate to recommend Sony cameras to people.  A7R5 can get my full endorsement if it also doesn't have the color concentric ring problem.  I am testing this now using Mark's recipe.  Stay tuned.

[Digitaliz.se]

I usually identify these problems as Chromatic Aberration. They appear on my cooled astrocamera as well.

 

/Stefan

 

Good for you.  I mean it.  Not sensitive to problems is actually a bless.  Sometimes I hate myself in the sense that I can't unseen problems after I see them.

 

When I looked at the three images you just showed, I see dark centers in many stars in the left one and the middle one.  I see green stars in the right one.  These are typical symptoms of star eater, and the end results of stacked images would be soft stars and/or a green tint in many stars.  A7R5 does not have any of these, and this is great news for Sony users.  I always hesitate to recommend Sony cameras to people.  A7R5 can get my full endorsement if it also doesn't have the color concentric ring problem.  I am testing this now using Mark's recipe.  Stay tuned.

[whwang]

So everything is the lens?  That's an interesting way of looking at things.

 

Anyway, it's not like you can do anything to improve it except for post processing.  Lens or the camera, the problem is already there the moment the images were taken.  

 

To me, it's still important to properly identify the root of the problem, so I know what to avoid in my next purchase.

[Digitaliz.se]

Everything is not about the lens, but the article you referred to stated that this was a lens issue which didn’t happen if you used the cameras a as a ”real” DSO camera, meaning using a telescope. The issue starts when the camera can identify the lens and uses its algorithm on it. You can deal with the ring problems in post, but that is not optimal of course.
The color around the stars are CA and is always caused by the lens/telecope.

The Star eater issue is however another matter. When using a non high resolution camera (like Sony A7S) with a  wideangle lens in a lightpolluted area, the stars will suffer greatly. Increasing the S/N ratio is a good way to handle problem. And I totally agree that identifying the root problem is important, but the most imortant to know is how to deal with problem.

 

So everything is the lens?  That's an interesting way of looking at things.

 

Anyway, it's not like you can do anything to improve it except for post processing.  Lens or the camera, the problem is already there the moment the images were taken.  

 

To me, it's still important to properly identify the root of the problem, so I know what to avoid in my next purchase.

[gregbradley]

I wonder if some of the other latest Sony models are good now.

 

It would also be good if Sony provided a firmware update for earlier models to implement this no star eater.

 

Greg.

[gregbradley]

That means the Sony A7r5 is now the ultimate nightscaping camera. That 61mp sensor is the best current CMOS sensor in dedicated astro cameras.

 

I predict it would also mean Nikon and Fuji who also have had star eater probably won't suffer from it anymore as the star eater, I assume,, is performed on-sensor and is not something Nikon or Fuji developed.

 

Greg.

Edited by gregbradley, 16 January 2024 - 04:45 PM.

[FrankieT]

I predict it would also mean Nikon and Fuji who also have had star eater probably won't suffer from it anymore as the star eater, I assume,, is performed on-sensor and is not something Nikon or Fuji developed.

Spatial filtering (aka Star Eater) is performed off-sensor. Nikon, Sony and I presume Fuji all use independent algorithms. For example, the Nikon Z6/II uses the same sensor as the Sony A7III but exhibits different spatial filtering characteristics. Nikon uses a filtering algorithm that causes less damage to stars in its more recent products. See Mark's in depth analysis here:

 

https://www.markshel...ng.html#NikonZ6

 

and here:

 

https://www.markshel...areater_v2.html

[erictheastrojunkie]

That means the Sony A7r5 is now the ultimate nightscaping camera. That 61mp sensor is the best current CMOS sensor in dedicated astro cameras.

 

I predict it would also mean Nikon and Fuji who also have had star eater probably won't suffer from it anymore as the star eater, I assume,, is performed on-sensor and is not something Nikon or Fuji developed.

 

Greg.

Fwiw the same sensor is in the Sigma FpL, there are pros and cons to both cameras, but I'd give the edge to the FpL ever so slightly in that the camera is smaller, lighter, with no IBIS, a passive heat reduction/heat sink to cool the body, and no evidence of star eater (not to mention dng output rather than Sony files. But if course the Sigma has no articulating screen and a few other features, plus no real great software control support, although there's a new driver supported by NINA available. 

[cometguy]

Definitely noticeable on a recently purchased A7iii.   You can see here the difference between a stretched 3.2 sec and 4.0 sec exposure.  At 4 seconds some additional filtering kicks in that tends to flatten out faint stars as well as smearing the background noise.   I think its perfectly OK for its intended use (comets, nightscapes, meteors, aurora, thunderstorms, etc).   Has anyone tried the A7CR?

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Edited by cometguy, 16 January 2024 - 09:47 PM.

[whwang]

Fwiw the same sensor is in the Sigma FpL, there are pros and cons to both cameras, but I'd give the edge to the FpL ever so slightly in that the camera is smaller, lighter, with no IBIS, a passive heat reduction/heat sink to cool the body, and no evidence of star eater (not to mention dng output rather than Sony files. But if course the Sigma has no articulating screen and a few other features, plus no real great software control support, although there's a new driver supported by NINA available. 

I like your analyses.  Indeed both have their pros and cons.  What you mentioned are also my concerns if one day I am to choose the two.

 

Let me throw in another point: the small lens mount of Sony.  The E mount was originally developed for APS-C cameras (NEX). Later Sony put a full-frame sensor behind the mount.  I guess Sony was not serious about this product and did not expect it to be such a big hit.  Anyway, the result is that if you put the camera behind a telescope with large focal ratio (>5), you will see severe vignetting in the corners.  It can be so severe that even flat-field correction does not really work in the extreme corners.  So if you plan to use a Sony E-mount FF camera on a telescope, you need to factor this in.  It's not a problem on lenses, as the light path from lenses is completely different.

Edited by whwang, 16 January 2024 - 10:08 PM.

[gregbradley]

I haven't used my Sony cameras directly on a scope so that is not something I knew of.

 

Sony also arguably has the best selection of lenses suitable for nightscaping. The Loxia 21 2.8, GM 24 1.4 and quite a few others.

 

Canon has fewer options.

 

Greg.