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NX1 exposure drift problem FIX

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EOSHD Pro Color for Sony cameras EOSHD Pro LOG for Sony CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

The two last firmwares have improved HD video, DOF, 4k DCI (not tested, if anyone can confirm ?) and fixed some bugs.
UHD is great in good light, better than GH4. But we really need control over noise reduction on low ISO. In low light or in dark areas of the image, some details are washed away, the GH4 is noiser but retain really more details.

 

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I'm on ver 1.4 with the NX-1 - I'm getting some serious drifting in exposure.  Other than checking my display auto-brightness setting and Framing guides, can you think of any reason?  Shot quite a bit in the bright noon sun yesterday and my footage is pretty bad even at 1/125 shutter and F/16 panning around.  I noticed the screen was flickering quite a bit as well; I'm sure it's just some setting I enabled by accident.  I do have the overexposure guide on.

Thoughts?

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Just did some tests.  Framing guides on/off had no ill effect for me.  Changing metering linked to spot focus didn't either.

However, changing metering to evaluative / spot metering AND having auto brightness on the display cured the problem for me with firmware 1.40.  Just an FYI.

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Just did some tests.  Framing guides on/off had no ill effect for me.  Changing metering linked to spot focus didn't either.

However, changing metering to evaluative / spot metering AND having auto brightness on the display cured the problem for me with firmware 1.40.  Just an FYI.

Think I've experienced something one of these days, too. Probably gonna happen everytime Samsung changes something major they don't have a full grip on (i.e.: almost everything). Still love what you can do with the DIS and vintage lenses, though. :p

Thanks for your input anyways!

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Question for you Agolex - are you on ver 1.4?  If so, put the display in "auto brightness" mode and the metering to "spot".  See if you can replicate the flickering / drifting.  Also I am using the 16-50 S lens with shutter and aperture set manually / Auto ISO.

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Auto ISO would change exposure as the scene changes, so that would be the source of your problem IMO. If you don't want exposure to change, you need to have ISO at a fixed value.

Also, if you are using autofocus and there is any sort of movement of the focus point, the field of view can change slightly, and that may alter your overall exposure.

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Question for you Agolex - are you on ver 1.4?  If so, put the display in "auto brightness" mode and the metering to "spot".  See if you can replicate the flickering / drifting.  Also I am using the 16-50 S lens with shutter and aperture set manually / Auto ISO.

I'm on 1.4, yeah. Sorry, but I have no time to test right now. It's no biggie, though, I'm not even sure anymore I had the issue, it might have been just the auto brightness of the display. Should have probably just shut up. :d

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Auto ISO would change exposure as the scene changes, so that would be the source of your problem IMO. If you don't want exposure to change, you need to have ISO at a fixed value.

Also, if you are using autofocus and there is any sort of movement of the focus point, the field of view can change slightly, and that may alter your overall exposure.

Tugela I realize this; been shooting for years.  I know the difference with fully manual mode ISO/EXP/Shutter locked.  I'm saying with metering set to SPOT and the display brightness set to "auto" I get very drastic / sudden exposure changes.  With the slightest movement.  Not so if I turn these both off.

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Here I am in August 2016, with all the latest firmware versions for my NX1 and lenses I own, at the end of life for both camera and support... and I still experience so many frustrating issues with this camera that can be otherwise so capable. I use it mostly for video in manual mode and manual iso mostly at UHD highest quality settings – and still have many occurrences of exposure drifting (mostly when panning) and focus hunting/breathing (depending on the lens). I can't always switch to manual focus in my work and manual focus can be difficult operate with some of the NX lenses. I've tried so many combinations of settings... I've set the Ael button to AFL and AEL which works better for me than touch focus. Maybe I should try more testing in aperture priority mode or look deeper into the settings – but I've had the camera for a year now and just have not found a way to use or reliably for the situations I need it to perform in.

I've read and tried tips and setting ideas on so many forums...

I end up going back to a Canon C100 for anything important even when I wish and want to use the NX1 instead. I don't want this to sound like a rant it's just this camera came so close to to doing everything I needed; it had such possibilities – and Samsung just gave up on it and its owners. I've never been so torn over camera as I have with the NX1.

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Focus changes with autofocus will happen with any camera.

Manual focus is pretty simple, if you compose in stills mode and then hit the record button. The focus by wire approach used in the S lenses allows for much more accurate fine focus adjustments than (for example, since I have them) Canon lenses.

I have never had exposure drifting happen in manual mode. It can happen in an auto mode, because then the camera is actively compensating for whatever is at the metering point.

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I don't know if this is connected but I'm getting micro exposure changes when I zoom in and out with the kit lens. If doesn't really make sense, is this normal? I set the aperture to f/5.6, shutter speed 1/60 and manual focus. How do you explain this change in exposure while zooming? If the lens maximum aperture is 5.6 why and how does it get darker/brighter?
IIRC it also happens with the 18-200, is this a "bug" of electronically controlled lenses?

 

Edit: it doesn't happen in still mode so it's a software issue...

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On ‎8‎/‎6‎/‎2016 at 6:48 AM, sandro said:

I don't know if this is connected but I'm getting micro exposure changes when I zoom in and out with the kit lens. If doesn't really make sense, is this normal? I set the aperture to f/5.6, shutter speed 1/60 and manual focus. How do you explain this change in exposure while zooming? If the lens maximum aperture is 5.6 why and how does it get darker/brighter?
IIRC it also happens with the 18-200, is this a "bug" of electronically controlled lenses?

 

Edit: it doesn't happen in still mode so it's a software issue...

The aperture adjusts as you zoom to get the correct amount of light for a particular f value, since your angle of view changes. This does not happen immediately since it is controlled electronically. It happens in stills mode as well, you just don't notice it because by the time you take your picture the adjustment has been made.

One of the prices you pay for a purely electronic lens. They likely all do it, not matter what manufacturer makes them. The only ones that won't are those that adjust the aperture mechanically through direct gearing to the zoom.

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12 hours ago, tugela said:

The aperture adjusts as you zoom to get the correct amount of light for a particular f value, since your angle of view changes. This does not happen immediately since it is controlled electronically. It happens in stills mode as well, you just don't notice it because by the time you take your picture the adjustment has been made.

One of the prices you pay for a purely electronic lens. They likely all do it, not matter what manufacturer makes them. The only ones that won't are those that adjust the aperture mechanically through direct gearing to the zoom.

I meant I don't see in still live view. It's almost unbelievable that even the $1500 S lenses basically make zooming during video useless due to these shifts.

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16 hours ago, sandro said:

I meant I don't see in still live view. It's almost unbelievable that even the $1500 S lenses basically make zooming during video useless due to these shifts.

Buried in one the 80-page threads here is a discussion about exposure change during zooming. Tugela is right, all electronic and some manual lenses do this. My takeaway from that whole discussion was that a lens that doesn't do this is a very expensive cinema lens. 

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18 hours ago, sandro said:

I meant I don't see in still live view. It's almost unbelievable that even the $1500 S lenses basically make zooming during video useless due to these shifts.

The reason you don't see it in live view in stills mode is because the aperture is wide open all the time. In video it is stopped down to the set value, and that is when the adjustments are made. With an electronic lens this is done independently. A true cine lens will have mechanical gearing to do it, but that is a more expensive option. Consequently modern electronic lenses designed primarily for stills just use the independent control. If it is really an issue for you then try using an old mechanical lens, although you will of course lose autofocus.

There was a thread about two months ago discussing this very issue, that you participated in, so you should know all of this already.

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So, even if I am using my 18-200 lens in the manual setting with fixed ISO, the aperture still changes? I have plenty of lenses that get darker as you zoom in despite aperture settings, but I'm seeing flickering exposure changes when panning and other strange behavior which should not happen when using the Manual setting...

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Yes, because the physical aperture size for F4 (for example) at 18mm is different from that at 200mm. The camera needs to adjust as you change the aperture, even if you have constant ISO selected, because it needs to increase aperture as the focal length increases to keep the amount of light hitting the sensor the same due to the narrower field of view.

Flickering exposure changes should not happen if you are fully manual. There are two reasons why it may be happening (1) you have something in auto mode that you don't know about; or (2) in very detailed areas (typically vegetation) you get micro-aliasing that will appear as rapid exposure changes when you pan. The solution to (2) is to reduce your resolution in some way, such as minimizing the sharpening. Sharpening artifacts are pretty minimal on an NX1, but they will aggravate the situation described, so if you are going to be panning it is best to drop sharpening way down. Incidentally, the flickering may not be apparent on all viewing devices since some (especially TVs) may introduce their own internal sharpening, which of course will make the problem manifest itself again.

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