A7RII LONG EXPOSURE IMAGE

[Guy Mancuso]

Okay here are the details . Shot with the A7RII after a rain storm about 3 in the morning. Lower lights are from a porch light and I lit the foreground trees with my iPhone. Yea its good for something.

Batis 25mm at F7.1 ISO 1250 for 1min and 28 sec. = 78 seconds

I had LE NR OFF.

Yes there are some hot pixels and I was able to reduce that in C1 with single pixel slider and color noise. But you folks can play all you want and see what you come up with.

Really the end of day question as a Raw shooter NR ON or OFF

Here is the raw. Fair warning do not use the image for commercial gain, Im very good at tracking you down. LOL


https://www.hightail.com/download/bXBieEVRQ3RFd2NaQ2NUQw

 

[Guy Mancuso]

My bad it was 88 seconds

 

[Vivek]

Guy, Hotpixels or just noise? Do they occur at the same position every time or move around?

 

[Guy Mancuso]

Guy, Hotpixels or just noise? Do they occur at the same position every time or move around?

I think its just noise. They are slightly different in another shot but Ill double check

 

[Guy Mancuso]

Guy, Hotpixels or just noise? Do they occur at the same position every time or move around?

I think its just noise. They are slightly different in another shot but Ill double check

Here are both files

https://www.hightail.com/download/bXBieEVRQ3Q3N0JMWE1UQw

 

[Stuart Richardson]

Does it take a dark frame? That's what most of the cameras I have used have done (Leica S, M9, Nikon D3 etc), and it seems a very effective tool for eliminating this problem. As it is now, I don't think I would use it for long exposures, as the results I get out of the S are extremely clean by comparison. But I think if they did a darkframe it would improve things dramatically. Or perhaps there is something else that Leica and Nikon are doing to tame this single pixel noise? Other than that, it looks like it has a great deal of potential...the results are still sharp and have good color. I know you were pushing it, but think you would get a cleaner file if you opened up the lens a bit and lowered the ISO...or just decreased the total exposure time.

 

[Guy Mancuso]

Turn LE NR on and it does a dark frame. Question is how aggressive it is to clean. A test I need to do.

Not sure I would use ISO 1250 for this htype of work. Rather I go lower open up a touch and maybe do focus stacking to get DOF back. I did it to push it to the limits or beyond. I want to try NR as well and see how aggressive it is without killing detail.

 

[spence]

Stuart,

The problem with doing a dark frame (turning on LENR) with the A7RII is that it drops from 13-bit, to 12-bit, precision.

At that point, with low ISO, you're giving away many of the sensor advantages, and might as well be shooting with an APS-C sensor.

It's a significant tradeoff, and one of the inexplicable compromises Sony requires with this sensor which leaves one scratching one's head.

 

[Viramati]

Stuart,

The problem with doing a dark frame (turning on LENR) with the A7RII is that it drops from 13-bit, to 12-bit, precision.

At that point, with low ISO, you're giving away many of the sensor advantages, and might as well be shooting with an APS-C sensor.

It's a significant tradeoff, and one of the inexplicable compromises Sony requires with this sensor which leaves one scratching one's head.

I seldom do long exposures so not much of an issue for me.
Question: Am I right in thinking though that it only goes to 12-bit with NR on if you use bulb mode and go above 30 seconds?

 

[Stuart Richardson]

Ha, ok...well, now I get it. That whole compressed RAW thing is very strange to me...especially when you need a 64gb card to use the nice video codec anyway, so it is not usually like space is at a premium on the capture side. It's one of those totally inexplicable choices...Leica did that with the T in forcing you to use DNG plus Jpeg. There was no way you could turn off the in camera jpeg, and no explanation as to why a camera aimed at least partially at serious photographers would omit that option!