a7rii long exposure color noise - quick rudimentary test

[Jamooche]

 

Dear Singingsnapper

1. Instead of noise reduction I think it’s better to take a black image (same exposure with lens cap on) every 30 minutes and do the rest in post processing by substracting.

 

 

How would one go about doing this?  How do you do the subtraction?

[EDBR]

This is the easy way http://www.takegreatpictures.com/photo-tips/software-tips-and-techniques/dark-frame-subtraction-using-adobe-photoshop-br-by-chris-limone

 

More complete and but more difficult used by most of "real" astrophotographers with telescopes (not like me) who take stack several tens of pictures and stack everytghing http://www.clarkvision.com/articles/astrophotography.image.processing/

[weinhous]

This is the easy way http://www.takegreatpictures.com/photo-tips/software-tips-and-techniques/dark-frame-subtraction-using-adobe-photoshop-br-by-chris-limone

 

More complete and but more difficult used by most of "real" astrophotographers with telescopes (not like me) who take stack several tens of pictures and stack everytghing http://www.clarkvision.com/articles/astrophotography.image.processing/

 

Thanks for those two links !

[Jamooche]

Thanks for those two links !

x2.  Thanks!

[justaguy]

Well i was lucky enough to shoot with my friends a7rii this morning at a little waterfall near me after work for about an hour as i was really anxious to see the verdict on long exposures as thats what i do a lot of and already knew the 7rii was great for regular shots looking through my buddies files he shot last week but the main thing i was interested in was how it would handle long exposures. Well to my liking i was very excited after shooting several shots at 200 seconds. I even underexposed one of them on purpose at 200 sec f/8 with two stacked nd filters and it is superb!!!

I played with the raw file in lightroom and couldn't find any color noise and the resolution is spectacular, i feel like it produced identical results i would get with my d810 but in a much smaller package, with evf, and in body stabilization,,, making me think now!

If enough of you would like to have a play with the raw file yourselves give me a thumbs up and i will upload it to drop box...

cheers!

[Jamooche]

Well i was lucky enough to shoot with my friends a7rii this morning at a little waterfall near me after work for about an hour as i was really anxious to see the verdict on long exposures as thats what i do a lot of and already knew the 7rii was great for regular shots looking through my buddies files he shot last week but the main thing i was interested in was how it would handle long exposures. Well to my liking i was very excited after shooting several shots at 200 seconds. I even underexposed one of them on purpose at 200 sec f/8 with two stacked nd filters and it is superb!!!

I played with the raw file in lightroom and couldn't find any color noise and the resolution is spectacular, i feel like it produced identical results i would get with my d810 but in a much smaller package, with evf, and in body stabilization,,, making me think now!

If enough of you would like to have a play with the raw file yourselves give me a thumbs up and i will upload it to drop box...

cheers!

Settings?  Did you have NR turned on?  

[bbphoto]

Settings?  Did you have NR turned on?  

 

I second these inquiries. Still trying to figure out if some copies are producing hot pixels and some not! 

[barrakj]

I second these inquiries. Still trying to figure out if some copies are producing hot pixels and some not! 

Ill do another test today, this time I will switch it to bulb, leave it running for at least 1 minute, and also disable all NR.

[Mlenny]

If you turn LONG TIME NR in camera to OFF you get those hot pixels if exposure time exceeds 2-3-4 seconds and you open the raw in ACR LRCC 2015. I tried it the last days with 3 different 7RII cameras.. All the same result, you see those hot pixels if you pump up exposure by +2 +3 in LRCC and look at the image with 200%, then you recognize it immediately. They DISAPPEAR if you enable Long Exposure NR = On. Then they are gone, BUT you have to wait twice the time for the NR processing. A 25s shot will be a 50s shot then...

 

With Capture One it`s easier to remove them than with LR as there is a special 'hot pixel removal' setting in the NR Menue of Capture One. With LR is not that easy as of today, maybe there will be an ACR update.

[barrakj]

Sorry guys can't test it without a remote apparently, thought the smart phone app would let me use bulb mode but it limits shutter speed to "30. Ill test it once im back from my trip.

[bbphoto]

If you turn LONG TIME NR in camera to OFF you get those hot pixels if exposure time exceeds 2-3-4 seconds and you open the raw in ACR LRCC 2015. I tried it the last days with 3 different 7RII cameras.. All the same result, you see those hot pixels if you pump up exposure by +2 +3 in LRCC and look at the image with 200%, then you recognize it immediately. They DISAPPEAR if you enable Long Exposure NR = On. Then they are gone, BUT you have to wait twice the time for the NR processing. A 25s shot will be a 50s shot then...

 

With Capture One it`s easier to remove them than with LR as there is a special 'hot pixel removal' setting in the NR Menue of Capture One. With LR is not that easy as of today, maybe there will be an ACR update.

 

While it pleases me to hear you have tried 3 copies of the camera with same result (guessing you got the widespread confetti look like I did), I've still read in a couple of forums a couple of other users whose copies did not produce more than 5/6 hot/warm pixels under same ISO 100 25 second exposures w/o LENR. Not sure if they're for real or if there are copies that don't exhibit this issue actually out there.

[EDBR]

So finished some tests regarding the hot pixels

 

You will only see these pixels in the darker parts of the image !

 

 

1. The quality of my new A7r M2 is worse than the ones taken with A7s or A7r M1 (the A7s is out of focus, was a dark room but enough to see it's ok)

2. Doing the  “blank hot pixel procedure" didn't change anything on my 3 camera's regarding hot pixels. You can hear that it's working on powering off but for me no change, the color seems to change

3. Did the  "subtraction" method and this helped but not 100%, see part of the image : A7r M2 100% nl picture & dark subtraction applied

4. In camera noise reduction ( Long Exposure NR)  is OK but takes to much time, doubles the exposure time, prefer a dark subtraction, you can make several in between a series of shots

5. Noise reduction on High ISO is only for jpeg, not an option for me

6. Sony you should do something here !!!! 

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[EDBR]

Oeps don't see anything on the net, didn't include sRGB color management 

Lets try again

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[EDBR]

So the images can be downloaded from dropbox

 

https://dl.dropboxusercontent.com/u/16913829/A7%20Total%20image.jpg

 

A7r versus A7s

https://dl.dropboxusercontent.com/u/16913829/A7r%20M1%20versus%20A7S.jpg

 

A7r versus A7r M2

https://dl.dropboxusercontent.com/u/16913829/A7r%20versus%20A7r%20M2%20copy.jpg

 

https://dl.dropboxusercontent.com/u/16913829/A7r%20versus%20A7r%20M2%20other%20part%20b%20copy.jpg

 

With substraction

https://dl.dropboxusercontent.com/u/16913829/A7r%20M2%20100%25%20nl%20picture%20%26%20dark%20substraction%20copy.jpg

 

Hope this works because the images on the net seem almost normal

[stephenv2]

Are these Capture One or ACR? If you check earlier ACR appears to have issue with raws from A7RM2.

[EDBR]

It's done in Lightroom

 

And didn't try this, just make a black image jpeg.

 

So good news for astrophotographers they can make great pictures of stars with the lens cap in place.

They don't even need to go outside or stay the whole night up 

 

https://dl.dropboxusercontent.com/u/16913829/Sony%20Galaxy.JPG

[DavidCartagena]

As an owner of an a900 and previously an a700 and KM7D I would say that it's a normal behaviour on long exposures. Unless you turn on in camera Black frame subtraction aka LENR you will get this result. Why the a7MII dosent show this so much I don't know. And remember the a7r II is double the MP compared to the a7.

 

There is nothing wrong with the camera imho.

 

David

[EDBR]

Dear David

 

1. Black frame subtraction : difficult if you want to perform timelapse or multiple images to make a pano ( see joined image 7 or 8 images, A7s with 14mm Samyang f2.8 30sec 8000asa)

But yes it solves the problem. Never done this on my Canon gear, Fuji or A7s A7r m1 because no problem with these....with a new camera it should be better no ?

https://dl.dropboxusercontent.com/u/16913829/KENIA-88.jpg

 

2. And remember the a7r II is double the MP compared to the a7: Of this I'm very well aware. But did you look to the image A7m I versus A7m II and not that great difference in mpix https://dl.dropboxusercontent.com/u/16913829/A7r%20versus%20A7r%20M2%20copy.jpg

No problem huge there....

 

3. Maybe it's a software isue that has to be solved, it's like the body & soft doesn't take in acount the remapping (every mounth "auto" action and tested, by changing the date, but no difference)

[Mlenny]

Hi David,

 

as i`m a newbie to the Sony Sensor World I don`t have that comparison. Anyway I own the D810 & 5DSR together, had the D800, 5D MKIII.. so within Nikon/Canon since 2004 beginning with the D1X and 1Ds. This just as a background. I really like the Sony A7RII BUT I did`t expect that behavior with Long Time Exposures and In Camera NR = OFF - as on ANY other Camera (see list above) I had switched of Long Time Exposure = OFF. Of course you see some minor slight pixels there too, but we are talking about maybe 3-4 to sum it up. But not about a whole Galaxy full of Hot Pixel Stars. I`m NOT complaining about the Camera itself, JUST about the RAW file it produces at exposures >1-2-3s with Long Time Exposure set to OFF. I hope there might be a firmware fix as soon as possible... Otherwise the Sony A7RII will be just a Daylight - Sunset - Sunrise Camera, but NOT suitable for Timelapses or longer Exposures (e.g. Waterfalls - Water smoothing longer exposures or Flatten the waves of the sea etc. etc.).

 

A fix is right now using Capture One Sony - there you can remove the Hotpixels easily, but i wanna stick with LR/PS workflow, so it`s a detour I don`t like....

[Singingsnapper]

Hi David,

 

as i`m a newbie to the Sony Sensor World I don`t have that comparison. Anyway I own the D810 & 5DSR together, had the D800, 5D MKIII.. so within Nikon/Canon since 2004 beginning with the D1X and 1Ds. This just as a background. I really like the Sony A7RII BUT I did`t expect that behavior with Long Time Exposures and In Camera NR = OFF - as on ANY other Camera (see list above) I had switched of Long Time Exposure = OFF. Of course you see some minor slight pixels there too, but we are talking about maybe 3-4 to sum it up. But not about a whole Galaxy full of Hot Pixel Stars. I`m NOT complaining about the Camera itself, JUST about the RAW file it produces at exposures >1-2-3s with Long Time Exposure set to OFF. I hope there might be a firmware fix as soon as possible... Otherwise the Sony A7RII will be just a Daylight - Sunset - Sunrise Camera, but NOT suitable for Timelapses or longer Exposures (e.g. Waterfalls - Water smoothing longer exposures or Flatten the waves of the sea etc. etc.).

 

A fix is right now using Capture One Sony - there you can remove the Hotpixels easily, but i wanna stick with LR/PS workflow, so it`s a detour I don`t like....

I don't have this issue and have been doing exposures of over 3 mins.  If you have Dfine, there is a hot pixels element to the filter that removes it all.  I had hot pies on both my D800 and D800E and also my Pentax 645Z.  Not large and circular, but small and lots of them.  

 

PS I hope you don't carry all your systems all at the same time!

[DavidCartagena]

Dear David

 

1. Black frame subtraction : difficult if you want to perform timelapse or multiple images to make a pano ( see joined image 7 or 8 images, A7s with 14mm Samyang f2.8 30sec 8000asa)

But yes it solves the problem. Never done this on my Canon gear, Fuji or A7s A7r m1 because no problem with these....with a new camera it should be better no ?

https://dl.dropboxusercontent.com/u/16913829/KENIA-88.jpg

 

2. And remember the a7r II is double the MP compared to the a7: Of this I'm very well aware. But did you look to the image A7m I versus A7m II and not that great difference in mpix https://dl.dropboxusercontent.com/u/16913829/A7r%20versus%20A7r%20M2%20copy.jpg

No problem huge there....

 

3. Maybe it's a software isue that has to be solved, it's like the body & soft doesn't take in acount the remapping (every mounth "auto" action and tested, by changing the date, but no difference)

Hi.

 

I didn't see the MkI and MkII comp. But I believe you.

 

I agree that it makes Panos at night and startrails somewhat difficult but not impossible. Make your own darkframes and then shoot.

 

But honestly I think you have to live with it. I don't think it's a fault and I don't think Sony will fix it.

 

David

[DavidCartagena]

Hi David,

 

as i`m a newbie to the Sony Sensor World I don`t have that comparison. Anyway I own the D810 & 5DSR together, had the D800, 5D MKIII.. so within Nikon/Canon since 2004 beginning with the D1X and 1Ds. This just as a background. I really like the Sony A7RII BUT I did`t expect that behavior with Long Time Exposures and In Camera NR = OFF - as on ANY other Camera (see list above) I had switched of Long Time Exposure = OFF. Of course you see some minor slight pixels there too, but we are talking about maybe 3-4 to sum it up. But not about a whole Galaxy full of Hot Pixel Stars. I`m NOT complaining about the Camera itself, JUST about the RAW file it produces at exposures >1-2-3s with Long Time Exposure set to OFF. I hope there might be a firmware fix as soon as possible... Otherwise the Sony A7RII will be just a Daylight - Sunset - Sunrise Camera, but NOT suitable for Timelapses or longer Exposures (e.g. Waterfalls - Water smoothing longer exposures or Flatten the waves of the sea etc. etc.).

 

A fix is right now using Capture One Sony - there you can remove the Hotpixels easily, but i wanna stick with LR/PS workflow, so it`s a detour I don`t like....

It's funny because every time I read a Astrophotography tutorial or just a long exposure tuto they often mention that you should turn off LENR. But I assure you it's not possible to shoot my a900 without BFST / LENR either in camera or manual.

 

Anyway I would rather have a larger DR than using a Canon sensor If I should choose. Regarding Nikon there is only one thing to say. They make better use of the Sony sensor! Too bad for Sony.

 

I will make a test shot tonight with my good old a900 so you can compare it to the a7rII.

 

 

David

[justaguy]

Settings?  Did you have NR turned on?  

 

 

I second these inquiries. Still trying to figure out if some copies are producing hot pixels and some not! 

Sorry for the late reply, Work comes before i can play LOL..

after reading all the hype on the color noise problem on here i went back through the 8 or so shots i got to take with his a7rii yesterday and did find a little bit of color noise in the darkest areas of the shadows and mind you i shot this underexposed by about a stop to a stop and a half and cranked up the shadow slider in lightroom and looked at it at 100% and found some of the color noise. The one shot was shot at f/8 iso 100 at 199seconds and yeah i forgot to turn off steady shot so some of that noise could have been from the magnetizer?

The second shot i took at 15 second exposure and could not find any noise whatsoever on that one.

Oh and noise reduction set to off in camera!

[justaguy]

It's funny because every time I read a Astrophotography tutorial or just a long exposure tuto they often mention that you should turn off LENR. But I assure you it's not possible to shoot my a900 without BFST / LENR either in camera or manual.

 

Anyway I would rather have a larger DR than using a Canon sensor If I should choose. Regarding Nikon there is only one thing to say. They make better use of the Sony sensor! Too bad for Sony.

 

I will make a test shot tonight with my good old a900 so you can compare it to the a7rII.

 

 

David

i have to agree 100% with you on Nikon making better use of Sony sensors!

I love the form factor, EVF, wifi, of the sony a7 series bodies, Sony should have took the A7rii and let nikon sprinkle their magic dust inside it before shipping it to buyers LOL..

[justaguy]

Here is the link to the raw file if you all want to have a play with it!

Remember this was shot at f/8 iso 100 at 199 seconds. I forgot to turn off steady shot so it was active which could play a part in magnetic noise (heat build up around sensor)?

This was using the 28-70mm kit lens. I have another shot at 30 second exposure and i could not find any trace of color noise and will upload that one too 

 

https://www.dropbox.com/s/jzvfvophp8htt22/_DSC9492.ARW?dl=0