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kye

When are we getting electronic variable ND filters?

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Most cameras can be set to 1/50th shutter, a desirable aperture, and automatic ISO, which means that if the scene gets a little darker the camera compensates.  This is what machines are for.

Why haven't we got the same thing when we are at base ISO and it gets a little brighter?  Even if purely electronic variable NDs aren't up to optical standards, why isn't there a high quality variable ND in there with a little motor to wind it back and forwards?

Shutter speed and aperture are artistic controls and should be in the hands of the operator, ISO and ND filters are not creative, therefore they should be automated.

It doesn't seem like an insurmountable technical problem to me - what's the deal?

(or if it is, why don't we have dual-ISO cameras where the second ISO is something like 5?)

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5 hours ago, kye said:

Most cameras can be set to 1/50th shutter, a desirable aperture, and automatic ISO, which means that if the scene gets a little darker the camera compensates.  This is what machines are for.

Why haven't we got the same thing when we are at base ISO and it gets a little brighter?  Even if purely electronic variable NDs aren't up to optical standards, why isn't there a high quality variable ND in there with a little motor to wind it back and forwards?

Shutter speed and aperture are artistic controls and should be in the hands of the operator, ISO and ND filters are not creative, therefore they should be automated.

It doesn't seem like an insurmountable technical problem to me - what's the deal?

(or if it is, why don't we have dual-ISO cameras where the second ISO is something like 5?)

This has been available for a couple years now. Aputure makes such a ND. You can buy it at all the major retailers.

 

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Perhaps new sensor tech will go a long way to solve the limited ISO issue. 

I've also wondered why radically low ISO's have not been unavailable on cameras. Too lazy to look up why. Figure it must be some sort of limitation in the tech that probably could be solved, but not worth the effort. 

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Interesting @DBounce I hadn't seen that.  If there are patents involved then maybe that's the reason. :(

None of these are AUTO electronic variable ND..  maybe I should have put that in the thread title.

We have AUTO shutter speed (in aperture priority or P-mode), we have AUTO aperture (in shutter priority or P-mode), we have AUTO ISO.....   why no AUTO ND?

I can understand why camera don't have a dual ISO, I would imagine that costs more to implement, but cameras already have built-in NDs, so why Canon doesn't just buy Aputure and install them (or license the tech) doesn't make sense.  In terms of manufacturing, both solutions require optical-quality tinted glass, room between the lens and the sensor, a motor, and some kind of control mechanism, and being able to say "Built-in auto variable ND" even seems like better marketing than "Built-In ND Filters with Manual Controls".

I'm guessing that eventually we'll have a camera that uses AI to recognise skin tones in various lighting situations using a combination of face detect and clever keying, will do some analysis on the dynamic range of those skin tones, and will then adjust exposure to keep the normalised mean skin tone exposure at a set exposure level (and if you're lucky it will be user-specified in IRE), but why we have to wait for Artificial Intelligence to get AUTO ND seems completely stupid to me.

I want a camera that I can set to 1/50, f2.8 and auto exposure and then go point it at people running around in full sun, point it at the sun during sunset, point it at people watching the sunset with golden hour exploding all over their faces, and then point it at people sitting around having wine and talking through blue hour and into night with practicals and candlelight, AND HAVE THE CAMERA DO AUTO EXPOSURE THAT WHOLE TIME.  This is what I need for my home videos of friends and family etc, but I'm sure that the run-and-gun doc filmmakers working in sketchy situations in the jungle, or war-torn cities would also appreciate one less thing they need to worry about.  

The less time I'm thinking about exposure, the more time I'm thinking about composition, camera angle, zoom vs distance to subject, the psychology of directing people (and trying not to make people uncomfortable), shot selection and how it will end up being used in the edit, and balancing the need to get good footage vs being on time for dinner.

In summary, GRRRR.

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Its here: Sony FS5, Sony FS7 have as an option built in auto variable electronic ND continuous smooth. Does exactly what you want - set shutter, aperture, ISO, and exposure is set automatically. Choose your DOF and not worry about lighting conditions. Great for run and gun, doc, eng. No need for clickless aperture lenses.

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Note that some people feel variable NDs tend to harm the image more than high quality NDs would. 

I think I recall watching an interview at an expo after the FS5 came out, with an engineer explaining how it wasn't an easy feat and the struggles they had. 

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2 hours ago, markr041 said:

Its here: Sony FS5, Sony FS7 have as an option built in auto variable electronic ND continuous smooth. Does exactly what you want - set shutter, aperture, ISO, and exposure is set automatically. Choose your DOF and not worry about lighting conditions. Great for run and gun, doc, eng. No need for clickless aperture lenses.

Excellent - thanks for letting me know.  In my case it's not the fact it's in the FS5 and FS7 which are both too large and expensive for me, but that it's been done and there's hope for trickle-down.

1 hour ago, IronFilm said:

Note that some people feel variable NDs tend to harm the image more than high quality NDs would. 

I think I recall watching an interview at an expo after the FS5 came out, with an engineer explaining how it wasn't an easy feat and the struggles they had. 

I suspected this.  I once bought a cheap variable ND from eBay and when I got it it worked well at minor attenuation, but when you started to really make it dark it got these strange banding interference patterns, which I suspected were due to imperfections in the alignment of the two coatings.  To get this to a level that is below what a 4k 16bit RAW (or higher) sensor can resolve would be no mean feat, so I was anticipating that the tech would likely be done some other way (LCD perhaps) but that it would be difficult to get up to quality standards.

Thanks guys, that answers my question :)

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On 2/15/2018 at 1:25 AM, kye said:

...Even if purely electronic variable NDs aren't up to optical standards, why isn't there a high quality variable ND in there with a little motor to wind it back and forwards?...It doesn't seem like an insurmountable technical problem to me - what's the deal?

In the mirrorless ILC form factor at APS-C size and above, it is a difficult technical and price problem.

Technical: No ND can go to zero attenuation while in place. To avoid losing a stop in low light, the ND must mechanically retract, slide or rotate out of the optical path. This is easier with small sensors since the optical path is smaller, so the mechanism is smaller.

A box-shaped camcorder has space for a large, even APS-C-size ND to slide in and out of the optical path. On the FS7 it slides vertically: https://photos.smugmug.com/photos/i-k7Zrm9Z/0/135323b7/L/i-k7Zrm9Z-L.jpg

There is no place for such machinery in the typical mirrorless ILC camera. That said, in theory if a DSLR was modified for mirrorless operation the space occupied by the former pentaprism might contain a variable ND mechanism. I think Dave Dugdale did a video speculating on this.

Economic: hybrid cameras are intended for both still and video use, and typically tilted toward stills. A high-quality, large-diameter internal variable ND would be expensive, yet mostly the video users would benefit. In theory the mfg could make two different versions, one with ND and one without, but that would reduce economy of scale in manufacturing.

Yet another option is an OEM designed variable ND "throttle" adapter. It would eliminate the ND-per-lens issue and avoid problems with the lens hood fitting over the screw-in ND filter. But this still has the issue of requiring removal every time you switch to high ISO shooting. 

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6 hours ago, IronFilm said:

Note that some people feel variable NDs tend to harm the image more than high quality NDs would. 

I think I recall watching an interview at an expo after the FS5 came out, with an engineer explaining how it wasn't an easy feat and the struggles they had. 

Where is the evidence of electronic variable ND's harming the image?  The FS5 and FS7 are principally used by pro videographers, and this feature has been available a long time. I have never heard about the electronic ND having any adverse effect - who are the "some people" who "feel" it harms the image? Pro videographers would certainly care and report about this. I have never seen any discussion of image degradation in any reviews, and I have read many. Give the link to any source.

This is typical internet bad behavior that leads to the propagation of nonsense. On the other hand, if you got a source that is credible and share it, that is very helpful indeed for the many users of this technology (who are according to you blind to the "harm" being done).

It is true that the electronic ND cannot go to zero light attenuation; it must be mechanically removed (and can be with just a turn of a knob). The ND can also be pre-set to a particular value like any ND using that knob.

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4 hours ago, joema said:

Economic: hybrid cameras are intended for both still and video use, and typically tilted toward stills. A high-quality, large-diameter internal variable ND would be expensive, yet mostly the video users would benefit. In theory the mfg could make two different versions, one with ND and one without, but that would reduce economy of scale in manufacturing.


In a future GHx it might not make sense to have a built in ND, but in a GHxS model which is almost exclusively targeted at video shooters? Would be excellent!

 

 

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