A7rii Hot pixels during long exposure.

Esstee said:

Graham Best said:

Esstee said:

Graham Best said:

Esstee said:

It looks as though the camera isn't applying long shutter NR
Which btw. all camera's do (automatically) as all sensors produce hot pixel noise in such conditions. Though the difference being, the A7R II may not address the noise automatically.

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With all the Sony cameras I've had, long exposure NR isn't performed "automatically", but is an option.

Edit:

All digital cameras do perform an automatic mapping of the sensor to remove hot pixels, usually monthly (and having nothing to do with long exposure NR). These hot pixels are normal to all sensors, and are a result of the manufacturing process. You might move your camera's date up to next month and see if you have any change.

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Most all camera's in existence perform long shutter NR to mitigate the noise created from the additional heat in the process. In most all systems, this is built-in and cannot be turned on or off.

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That's interesting but what does that have to do with Sony camera's long exposure NR or this thread? As I said, it's a menu option (camera menu, pg. 5 on the a7r) on Sony cameras.

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Because this would leave two options in my view:

1. the system is present but none functional (needs FW to correct)

2. the system can be toggle on or off by the user.

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Long exposure NR "works" by taking another exposure, equal in time to the first exposure but with the shutter closed. The procedure is the same in all cameras.

Ignorance is shared by all, and corrected by education. Arrogant ignorance is a character flaw.

Esstee said:

SQLGuy said:

It's 2. And the OP already stated that he doesn't want to use it, and has disabled it.

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Then I see no issue here whatsoever.
Either the user chooses to turn on long shutter NR so as to have what other camera's have or he doesn't and deals with the effects of heat alternatively. Which isn't all bad if/when you think of it as I find most RAW developers address hot pixels better than in camera systems to begin with.

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I'm guessing he's using some sort of RAW developer for the samples posted, and it did not address the noise.

I'm also guessing, or he may have even stated it, that the OP doesn't want to use LENR because of the resultant loss of DR (12 bits instead of the theoretical 14).

SQLGuy said:

I'm guessing he's using some sort of RAW developer for the samples posted, and it did not address the noise.

I'm also guessing, or he may have even stated it, that the OP doesn't want to use LENR because of the resultant loss of DR (12 bits instead of the theoretical 14).

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Makes sense.

I noticed that Camera Raw and LR don't do this. Whereas Raw Therapee and Capture One do a good job at removing the heat noise. Though without seeing, I can't comment on whether they do a better job than with the onboard system however.

PS. I'd love to see a test to contrast the advantages of 12 vs 14bit files in such cases. ie, whether it is worth the added work of post processing etc.

Maple888 said:

i would usually take multiple shots and then merge them together to average the noise out anyway.But for long timelapses its not ideal.

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Can you please give me more details on how you do this and under what conditions?

Thanks!

Graham Best said:

Esstee said:

Graham Best said:

Esstee said:

Graham Best said:

Esstee said:

It looks as though the camera isn't applying long shutter NR
Which btw. all camera's do (automatically) as all sensors produce hot pixel noise in such conditions. Though the difference being, the A7R II may not address the noise automatically.

Click to expand...

With all the Sony cameras I've had, long exposure NR isn't performed "automatically", but is an option.

Edit:

All digital cameras do perform an automatic mapping of the sensor to remove hot pixels, usually monthly (and having nothing to do with long exposure NR). These hot pixels are normal to all sensors, and are a result of the manufacturing process. You might move your camera's date up to next month and see if you have any change.

Click to expand...

Most all camera's in existence perform long shutter NR to mitigate the noise created from the additional heat in the process. In most all systems, this is built-in and cannot be turned on or off.

Click to expand...

That's interesting but what does that have to do with Sony camera's long exposure NR or this thread? As I said, it's a menu option (camera menu, pg. 5 on the a7r) on Sony cameras.

Click to expand...

Because this would leave two options in my view:

1. the system is present but none functional (needs FW to correct)

2. the system can be toggle on or off by the user.

Click to expand...

Long exposure NR "works" by taking another exposure, equal in time to the first exposure but with the shutter closed. The procedure is the same in all cameras.

Ignorance is shared by all, and corrected by education. Arrogant ignorance is a character flaw.

Click to expand...

Have you taken a long exposure with a Canon 5Diii? Because it does not take a dark frame after the exposure that is equal to the first shutter time.

The process varies and Sony's isn't the best by any means. A lot of trade offs with the Sony nap much so I have contemplated returning my a7Rii.
--
http://www.14fps.tv - My YouTube channel with a focus on Sony cameras.

FF Pro said:

Have you taken a long exposure with a Canon 5Diii? Because it does not take a dark frame after the exposure that is equal to the first shutter time.

The process varies and Sony's isn't the best by any means. A lot of trade offs with the Sony nap much so I have contemplated returning my a7Rii.

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Understandable. Though I'd add that I think most of the issues we've seen to date can be addressed in FW.

That said, I've made it my personal policy to never invest in new camera's until they've been thoroughly tested and debugged first. Which hold especially true for camera's sporting new tech.

The camera will automatically take a blank photo every so often Ayer you turn it off, and will map them out.

To manually trigger this process, set the date 2-3 months forwards, turn the camera off and you'll get the mapping shot. Then set the date back to today.

I had this on my a7r ii and they got mapped out this way.

Stupid autocorrect. That was after not Ayer

ncsakany said:

The camera will automatically take a blank photo every so often Ayer you turn it off, and will map them out.

To manually trigger this process, set the date 2-3 months forwards, turn the camera off and you'll get the mapping shot. Then set the date back to today.

I had this on my a7r ii and they got mapped out this way.

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Wow this is awesome info.

Hope someone can do a before/after using this method. - thx

Esstee said:

Wow this is awesome info.

Hope someone can do a before/after using this method. - thx

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Full-size crops. Make sure you click the 1:1 (100%) view option

ncsakany said:

Esstee said:

Wow this is awesome info.

Hope someone can do a before/after using this method. - thx

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Full-size crops. Make sure you click the 1:1 (100%) view option

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Excellent! Couldn't ask for better.
Just to confirm, these from the A7R II yes?

Yes

Astrophotographer 10 said:

That is definitely worse than a7R. I have never seen an a7R 30 second shot like that with that many hot pixels. I am a bit shocked. I thought it was supposed to be cleaner.

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...and yes, while it's worse, I've always had to use LENR on my A7R as well. It also produces an unacceptable file without LENR, at least by my standards. Ditto the D800, D800E and the D810 to an extent. The only camera/sensor that doesn't is the Sony 24mp in the RX1, A7 and D610. Annoying, but apparently a fact of life.

ncsakany said:

The camera will automatically take a blank photo every so often Ayer you turn it off, and will map them out.

To manually trigger this process, set the date 2-3 months forwards, turn the camera off and you'll get the mapping shot. Then set the date back to today.

I had this on my a7r ii and they got mapped out this way.

Click to expand...

I will try this later, i'm surprised this needs doing on such a new camera that has taken around 100 shots.Also it will be interesting to see how quickly this starts to come back into the shots for example if i start a 500 shot timelapse after say 300 shots would you start to see it reappearing.

Maple888 said:

ncsakany said:

The camera will automatically take a blank photo every so often Ayer you turn it off, and will map them out.

To manually trigger this process, set the date 2-3 months forwards, turn the camera off and you'll get the mapping shot. Then set the date back to today.

I had this on my a7r ii and they got mapped out this way.

Click to expand...

I will try this later, i'm surprised this needs doing on such a new camera that has taken around 100 shots.Also it will be interesting to see how quickly this starts to come back into the shots for example if i start a 500 shot timelapse after say 300 shots would you start to see it reappearing.

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My hunch is that on some cameras this step just wasn't performed at the factory prior to shipping stock to stores.

Esstee said:

FF Pro said:

Have you taken a long exposure with a Canon 5Diii? Because it does not take a dark frame after the exposure that is equal to the first shutter time.

The process varies and Sony's isn't the best by any means. A lot of trade offs with the Sony nap much so I have contemplated returning my a7Rii.

Click to expand...

Understandable. Though I'd add that I think most of the issues we've seen to date can be addressed in FW.

That said, I've made it my personal policy to never invest in new camera's until they've been thoroughly tested and debugged first. Which hold especially true for camera's sporting new tech.

Click to expand...

I should also add I don't believe this is only an a7Rii issue. I just posted a thread similar to this a few weeks back regarding my a7ii. I have never used LENR in camera and ALWAYS handled LENR in post processing. I have taken excellent photos with the a7ii without LENR and then all of a sudden I found an issue I could not correct for in Adobe Lightroom alone. The photo (in the thread below) was underexposed in a two main areas. I ended up having to blend two photos in Photoshop to get the noise out. First time in a long time I have had to do that.

a7ii noise in darks - http://www.dpreview.com/forums/thread/3881332

Sony is not Canon or Nikon. Firmware updates that address issues like this may or may not appear. Firmware updates may or may not fix legitimate issues we complain about or notice. It is Sony we are talking about and sometimes I believe Sony prefers releasing an updated body rather than a firmware update (a bit of sarcasm). If you wait to invest in Sony so they won't be buggy, keep waiting. I am a little perturbed at the Long Exposure caveats with the a7Rii.

Hi Maple888,

not sure what your point is, if any?

You have removed key EXIF data, such as Aperture - why?

Anyway:
- even assuming a relatively large aperture, needing 30secs at ISO 800 suggests this shot was done at somewhere around -6EV if not darker. That's the light level of a quarter moon, or an aurora borealis - not the moon or the aurora themselves, but the ambiant light generated by them.
- and as if this were not enough, you've cropped to just 1/18th of the total image, i.e. less than 1/4th in each dimension. And as if this were not enough, you're looking at it at 100%.

I'm not interested in doing such testing, but I'm ready to bet that many if not most cameras, under similar circumstances, might deliver comparably "poor" results. You say that your A7r does better - can you show a sample shot?

By the way, when doing long exposures people generally stay at ISO 100 - they amplify the ambient light by exposing longer, not by boosting the ISO. Even then, you say that Sony's long exposure NR does the job.

So I'm really not sure what you're trying to prove? That any camera used in a really unreasonable way, can deliver un-clean shots? Are you in the same camp as those people who do 30 seconds ISO 25'600 exposures with the lens cap on, and protest that the "result" is not perfectly black?

Maple888 said:

I was just testing the camera doing long exposures ready for a trip to Iceland and found i was getting these results. This seems to be a similar problem that people complained about when they upgraded from the Olympus OM-D E-M5 to the Olympus em1, the em1 had this hot pixel problem in the shots unless LE NR was set to on, where as the em5 was much cleaner without having to have the NR on.

I did shots at iso 800 with shutter speeds from 2 to 30 seconds and LE NR off and found that the problem starts to get bad at around 5s onwards.Turning LE NR on gave a clean file.I then did the same test with my A7r and found that it was no where near as bad.

This is a bit disappointing as i was planing to use this for night timelapses now you are able to power from usb.

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antoineb said:

Hi Maple888,

not sure what your point is, if any?

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Not sure what point your reply is

You have removed key EXIF data said:

Anyway:
- even assuming a relatively large aperture, needing 30secs at ISO 800 suggests this shot was done at somewhere around -6EV if not darker. That's the light level of a quarter moon, or an aurora borealis - not the moon or the aurora themselves, but the ambiant light generated by them.
- and as if this were not enough, you've cropped to just 1/18th of the total image, i.e. less than 1/4th in each dimension. And as if this were not enough, you're looking at it at 100%.

I'm not interested in doing such testing, but I'm ready to bet that many if not most cameras, under similar circumstances, might deliver comparably "poor" results. You say that your A7r does better - can you show a sample shot?

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yes i could but no need other people have already confirmed a7r doesnt show the same level of noise

antoineb said:

By the way, when doing long exposures people generally stay at ISO 100 - they amplify the ambient light by exposing longer, not by boosting the ISO. Even then, you say that Sony's long exposure NR does the job.

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Thanks for this info i didnt realize you could use iso 100 and expose for longer i am sure iso 100 works well for star trails.you would not use LE NR for time lapse

antoineb said:

So I'm really not sure what you're trying to prove? That any camera used in a really unreasonable way, can deliver un-clean shots? Are you in the same camp as those people who do 30 seconds ISO 25'600 exposures with the lens cap on, and protest that the "result" is not perfectly black?

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Used in a unreasonable way all the shots that i was looking at were iso 800-6400 and 8-30s exposures which are regularly used in night and star trail photography and time lapses. I was highlighting the problem as it looks like if you were thinking of this camera to use for time lapse at night then i might not be the best option.

antoineb said:

Maple888, post: 56287960, member: 524177"]


I was just testing the camera doing long exposures ready for a trip to Iceland and found i was getting these results. This seems to be a similar problem that people complained about when they upgraded from the Olympus OM-D E-M5 to the Olympus em1, the em1 had this hot pixel problem in the shots unless LE NR was set to on, where as the em5 was much cleaner without having to have the NR on.

I did shots at iso 800 with shutter speeds from 2 to 30 seconds and LE NR off and found that the problem starts to get bad at around 5s onwards.Turning LE NR on gave a clean file.I then did the same test with my A7r and found that it was no where near as bad.

This is a bit disappointing as i was planing to use this for night timelapses now you are able to power from usb.

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[/QUOTE]

Brilliant post! Well done.

Yes that makes sense. The hot pixel/dead pixel sensor map isn't updated. I've seen posts about how to trigger this on a Fuji or a Nikon. They all have a dead/hot pixel map which is subtracted from the image you take to clean it up. This is not specific to Sony and not a trait of the a7Rii.

As another poster pointed out chances are this step was missed in the factory. Later shipments are just as likely to have this corrected. At least its a minor thing even if annoying and more importantly not a bad trait of the a7Rii.

Greg.

Astrophotographer 10 said:

Brilliant post! Well done.

Yes that makes sense. The hot pixel/dead pixel sensor map isn't updated. I've seen posts about how to trigger this on a Fuji or a Nikon. They all have a dead/hot pixel map which is subtracted from the image you take to clean it up. This is not specific to Sony and not a trait of the a7Rii.

As another poster pointed out chances are this step was missed in the factory. Later shipments are just as likely to have this corrected. At least its a minor thing even if annoying and more importantly not a bad trait of the a7Rii.

Greg.

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Unfortunately this didn't seem to work for me I have tried it a couple of times and the camera defiantly does something as when you turn the camera off after moving the date forward you hear a mechanical click followed by a shutter release which you dont get simply by turning the camera off.