BJL

Lives in United States United States
Joined on Dec 17, 2002

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Total: 418, showing: 81 – 100
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BJL: About sensor size and those who want a larger sensor like 4/3" (or Super 35mm):
1) Video shutter speeds are fairly low: about twice the frame rate, so 1/60s for 30fps and so on. So the desire for high usable ISO speeds for the sake of high shutter speeds is less of an issue here than with still cameras for action photography.
2) A lot of usage is likely to be telephoto, and then (as always) doubling sensor format size doubles the focal lengths needed, so the lenses are either vastly heavier or keep weigh comparable by having about double the minimum f-stop, and so need to be operated at four times the ISO speed: not much of a gain, so long as the 2/3" sensor has enough DR.
3) Extremely shallow DOF is rarely desirable for broadcast videography, as distinct from pre-planned cinematic photography.

In fact, some good (and expensive) movies have been shot on 2/3" sensors.

@Ed, I agree that different shutter angles and frame rates are sometimes used for video, but this camera is aimed at broadcast work (like TV studios), where I expect that it is going to be 30fps and standard shutter angle most or all of the time. Looking at other broadcast TV cameras, the sensor size range seems to be 1/2" to 1", with even some far more expensive models than this using three 1/2" sensors. For comparison, the sensor in this one seems to be a bit bigger than 2/3", slightly smaller than 1" format.

Link | Posted on Feb 10, 2018 at 17:25 UTC

About sensor size and those who want a larger sensor like 4/3" (or Super 35mm):
1) Video shutter speeds are fairly low: about twice the frame rate, so 1/60s for 30fps and so on. So the desire for high usable ISO speeds for the sake of high shutter speeds is less of an issue here than with still cameras for action photography.
2) A lot of usage is likely to be telephoto, and then (as always) doubling sensor format size doubles the focal lengths needed, so the lenses are either vastly heavier or keep weigh comparable by having about double the minimum f-stop, and so need to be operated at four times the ISO speed: not much of a gain, so long as the 2/3" sensor has enough DR.
3) Extremely shallow DOF is rarely desirable for broadcast videography, as distinct from pre-planned cinematic photography.

In fact, some good (and expensive) movies have been shot on 2/3" sensors.

Link | Posted on Feb 10, 2018 at 00:14 UTC as 32nd comment | 4 replies
In reply to:

virtualreality: It's time to ditch the "D". Are they actually selling any non-digital cameras?
Compressed font D7500, it doesn't look good, even on DSLR with huge real-estate.

I agree: the Nikon F6 is the only Film SLR still being _sold_ new (and probably none has been _manufactured_ for years) and I have been calling them FSLRs for years now. I doubt that many people would be confused by saying just SLR for the whole category; it is as if we still called automobiles "horseless carriages".

But as this whole SLR category in now starting to slowly follow FSLRs into the sunset, it is probably too late to bother with any renaming.

Link | Posted on Jan 23, 2018 at 22:20 UTC
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ilza: OK, so this is a “composite sensor” which reads information from 200,000,000 locations in the focal plane. What makes it it a 400MPix sensor?!

(Just for completeness: out of these 200MPix, 100% are read in G, 75% in R, and 75% in B.)

The first four measurements are at the same 100 million locations (10,000 by 10,000) and then the fifth and sixth readings are centered at different locations, straddling the previous locations, so 300 million locations in total, with 20,000 different horizontal locations and 20,000 vertical. After that, the use of 400 million output pixels is just the 20,000 X 20,000 rectangular array of output pixels needed to cover the 20,000 horizontal and 20,00 vertical positions.

Link | Posted on Jan 19, 2018 at 17:52 UTC
In reply to:

ilza: OK, so this is a “composite sensor” which reads information from 200,000,000 locations in the focal plane. What makes it it a 400MPix sensor?!

(Just for completeness: out of these 200MPix, 100% are read in G, 75% in R, and 75% in B.)

The sensor has 100 million _photosites_, and the shifting is used to make 600 million readings, used to produce 400 million _pixels_. The difference between "photosites" and "pixels" is important here, as it has been demonstrated by several previous multi-shot shifting sensor cameras that this process can give more real resolution/detail that the photosite count is capable of without multi-shot. (By the way, this success has also shown that fears of current lenses not being able to keep up with the resolution increases of new bodies are exaggerated.)

Link | Posted on Jan 18, 2018 at 17:32 UTC
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Mike Davis: Pixel-shifting increases pixel counts without increasing the sensor dimensions. The diameter of Airy disks at the sensor plane will not shrink for any given aperture and wavelength of light, just because you started pixel shifting to quadruple the number of captured MP.

Pixel-shifting is great for increasing the resolution in the final print without increasing the print dimensions, but if you try to increase enlargement factor, you'll be increasing the size of the Airy disks in the final print, unless you open the aperture proportionately, to compensate the increase in enlargement factor.

In other words, if you're happy with the print resolution you're getting with 100 MP from this size sensor, you'll have to open up two stops to make a print that's twice as large, for the same desired print resolution and viewing distance. How does shooting at f/4.8 (instead of f/9.6) to avoid inhibiting a desired print resolution of 5 lp/mm in a 360 dpi un-resampled print sound?

Yes, 400MP wil have somewhat limited DOF once the aperture is large enough to avoid excessive diffraction. Maybe that is why it is marketed for art reproduction: photographing essentially flat subjects.

But no, format size has got nothing do with this limitation. For example, doubling sensor and pixel size would allow doubling the Airy disk diameter and so doubling the usable f-stop, but due to the doubled focal length also involved, that would gives circles of confusion at the focal plane also of twice the diameter. So if images from two formats are printed at equal image size, the prints have equal sized Airy disks and circles of confusion: same diffraction effects, same OOF effects.

Link | Posted on Jan 17, 2018 at 20:34 UTC
In reply to:

evilmagicnut: I expect those percentages are percentage of units sold. I'd be interested to know what the Canon / Sony / Olympus mirrorless breakdown is when you start talking revenue.

For mirrorless, revenue probably moves up both Sony (with its 35mm format bodies) and Panasonic (with its main strength in higher end "video first" gear). Anyway, the MFT system as a whole probably holds first place amongst mirrorless systems by either ranking.

P. S. Why does this ranking not even publish market share percentage beyond third place?

Link | Posted on Jan 17, 2018 at 20:21 UTC
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toughluck: If Nikon has any sense, they will throw in one or two F-mount adapters for free with the camera. One for AF-S lenses only, the other for AF-S and screwdriver lenses.

I agree that there should be an adaptor, particularly for any 36x24mm format Z mount body — and I am sure there will be. But there will also be a lot of entry level customers using only Z-mount lenses, and increasing the price for them by including an unwanted adaptor with _every_ camera would be bad for sales. It might make sense to bundle the higher end 36x24mm format bodies with an adaptor

Link | Posted on Jan 16, 2018 at 18:03 UTC
In reply to:

toughluck: If Nikon has any sense, they will throw in one or two F-mount adapters for free with the camera. One for AF-S lenses only, the other for AF-S and screwdriver lenses.

There is no such thing as "free" here; just "included in the price whether you want it or not". That would be passing on part of the cost to customers who have no need for such adaptors.

Link | Posted on Jan 15, 2018 at 14:41 UTC
In reply to:

AlwaysLiveView: Nikon, FF is really only needed by a small segment of the high end market. Make your first mirror-free professional camera an aps-c, and make it the best camera you have ever made. Take the Samsung (what did Sam sing?) NX1 as the starting point, and just dazzle us with what a camera can be. You can do it, you’ve done it before, in the middle of the last century. I remember; yes I’m that old, but still snapping.

Agreed, and I strongly expect that there will be a "DX" format Z-mount body first, even if there is also an FX body at the same time. For one thing, the Z-mount lens system will surely be limited at first, so the easiest market is first-time entry-level ILC camera buyer who are happy to start with just a few of the initially available Z-mount lenses.

Link | Posted on Jan 15, 2018 at 14:37 UTC
In reply to:

NCB: There's nothing to prevent Nikon producing a short flange MC, + an adaptor, together with an F mount version for those who are interested in MC but also just want to keep on using F mount lenses. Overheads in doing so would be fairly small. Whether it's worthwhile is another matter. I suspect they'll just keep on producing DSLRs in parallel with MC.

The F-mount version will be a kit consisting of the Z-mount body plus a Z-to-F adaptor. For those who do not like adaptors and the lens choice flexibility that they offer, Nikon could offer a service in which the adaptor is welded or glued to the body before shipping.

(Yes, I am sure that Nikon will also continue to produce F-mount DSLR bodies and lenses for some years.)

Link | Posted on Jan 15, 2018 at 14:34 UTC
In reply to:

CosminMunteanu: Hehe, most Nikon lenses have mechanical aperture coupling with the body. A simple adapter would not be enough to control the aperture through the body like is the case for canon AF EF lenses (on Canon M-EF, Sony E or m4/3 mount cameras). I do not know if there is a EF to X Fuji AF able adapter.

@SantaFeBill: your are right; I had the lens-body compatibility problems back-to-front.
Anyway, a good Z-F adaptor would require mechanical pass-through for the lever that stops the lens down to taking aperture. That could add a bit to the cost, but I do not see it as a major obstacle.

(On the other hand, I am fairly sure that there will not be an in-body AF motor, cutting off the earlier AF lenses that require one.)

Link | Posted on Jan 15, 2018 at 14:29 UTC
In reply to:

cosinaphile: the only limitations to lens design are achieved by embedding the sensor deeper into the camera, the shallower to sensor to flange distance the more options exist especially for wide angle lenses that have always challenged the depth of the typical dslr with its 20 +mm mirror box .... typically the best wides called for mirror locklup to circumvent this limitation .

it makes zero sense to retain the f mount for a new mirrorless ... current
dslr lenses can never work directly on the camera mount or no mount due to being too close ...if anything it would cause confusion for current nikon users unwilling to wrap their heads around the technology of mirrorless camera and lenses

however if is nikon is wise they will sell the camera with an adapter to simulate the mirrorbox distance and perfect electronic compatability with their lens lineup

I do not think most Nikon users will be confused: Z-mount cameras will work with Z-mount lenses; using F mount lenses on them will require an adaptor. It is the same as with using Canon EF or EF-S SLR lenses on its EOS-M mirrorless bodies, Sony/Minolta A-mount lenses on Sony's mirrorless E-mount bodies, or Four Thirds SLR lenses on Micro Four Thirds bodies.

Link | Posted on Jan 14, 2018 at 04:32 UTC
In reply to:

CosminMunteanu: Hehe, most Nikon lenses have mechanical aperture coupling with the body. A simple adapter would not be enough to control the aperture through the body like is the case for canon AF EF lenses (on Canon M-EF, Sony E or m4/3 mount cameras). I do not know if there is a EF to X Fuji AF able adapter.

Already, all current and recent Nikon DSLR bodies only work fully with lenses that have electronic aperture control (indicated by an "E" after the aperture in the lens name). This means most Nikon lenses from the last five years. So yes, many older lenses ("G" and before) will not be usable, but those lenses are already out in the cold with recent Nikon DSLRs.

Link | Posted on Jan 14, 2018 at 04:19 UTC
In reply to:

anticipation_of: So Kodak is a zombie brand now. Just a name and logo that anybody with a few bucks can license and slap on their crap to help it stand out among the sea of generic, no-name garbage on Amazon. Or among the sea of me-too cryptocurrency grifters, it would seem. Sad to see the tattered remains of such an iconic organization being paraded around like this. It’s undignified.

Richard: correct me if you know otherwise, but AFAIK:
(1) The motion picture film business was retained entirely by Eastman Kodak.
(2) There is no evidence that Kodak Alaris has acquired any film development or manufacturing assets: it is purely an intermediary between the film manufacturer and the market.
So I am quite confident that the new 8mm Ektachrome movie film, along with _all_ Kodak branded film, is both developed and manufactured by Eastman Kodak.

Link | Posted on Jan 13, 2018 at 19:33 UTC
In reply to:

BJL: I can see one reason for this variable aperture: for adequate DOF in extreme close-ups ("macro"). f/1.5 on a 1/2.55" sensor [as in the S8] has DOF like f/10 in 36x24mm format, which is usually plenty, but not always enough for some macro shots. And phone-cameras can be rather good at those.

A few other possibilities have already been mentioned, like wanting a lower shutter speed in some bright light scenarios. (Is there a flash sync speed limit with phone-cameras?)

DWinter: my OP in this subthread entirely about DOF, and why the S9 might want to stop down from f/1.5 for the sake of adequate DOF. No need to reopen the entire aperture ratio/ISO speed/exposure speed/focal length/FOV equivalence can of worms!

Link | Posted on Jan 13, 2018 at 19:26 UTC
In reply to:

SantaFeBill: IF this turns out to be true, Nikon IMHO has just again shot itself in the proverbial location.
This would mean that, to use F-mount lenses on the new camera, an adapter would have to have optics to somehow compensate for the longer focal flange distance that F-mount lenses are designed for.
Such an adapter would 1) add weight, how much depends on how complex the formula has to be; 2) likely degrade image quality, again how much depends on the complexity of the design - but the more complex, to help image quality, the more weight.
One great strength of Nikon has been keeping the F-mount compatibility. With a slight modification, I can use lenses on my Nikon DSLRs that I bought in the 1960s, if I choose to do so.
For Nikon to break this would, I believe, be a very serious mistake. I'm not going to buy a Nikon mirrorless if that means I have to start buying lenses all over again.

About Z mount having different contacts: unless we for some reason assume gross incompetence and/or evil without any evidence, it seems most likely that Nikon will do what Olympus, Panasonic and Sony have done: add contacts to support new features while maintaining support for the contacts and signaling used by existing modern F-mount lenses when adaptor mounted.

Link | Posted on Jan 12, 2018 at 20:22 UTC
In reply to:

anticipation_of: So Kodak is a zombie brand now. Just a name and logo that anybody with a few bucks can license and slap on their crap to help it stand out among the sea of generic, no-name garbage on Amazon. Or among the sea of me-too cryptocurrency grifters, it would seem. Sad to see the tattered remains of such an iconic organization being paraded around like this. It’s undignified.

Richard: maybe, but since Eastman Kodak still makes motion picture film (at least for now!) my understanding is that it simply kept that manufacturing facility for both of these closely-related product lines, and that the still films produced are all "Eastman Kodak" designs. AFAIK there has not been a new "Kodak Alaris" film introduced. Even the new, slightly updated, Ektachrome revival is being produced for motion (8mm) as well as stills, so it is almost certainly designed by Eastman Kodak.

That is, both the design and the manufacturing of these films are by Eastman Kodak: that is the quality guarantee that I was alluding to.

Link | Posted on Jan 12, 2018 at 20:18 UTC
In reply to:

tinternaut: Doesn’t a very short flange distance make it harder to design lenses that are sharp across the frame?

No, because for one thing any optical design that works with a longer flange depth can also be used with a shorter one: the lens body just protrudes further behind the rear lens element. So "shallower" only adds options in lens design. The same is true about it being wider than the F mount.

Link | Posted on Jan 12, 2018 at 20:07 UTC
In reply to:

SantaFeBill: IF this turns out to be true, Nikon IMHO has just again shot itself in the proverbial location.
This would mean that, to use F-mount lenses on the new camera, an adapter would have to have optics to somehow compensate for the longer focal flange distance that F-mount lenses are designed for.
Such an adapter would 1) add weight, how much depends on how complex the formula has to be; 2) likely degrade image quality, again how much depends on the complexity of the design - but the more complex, to help image quality, the more weight.
One great strength of Nikon has been keeping the F-mount compatibility. With a slight modification, I can use lenses on my Nikon DSLRs that I bought in the 1960s, if I choose to do so.
For Nikon to break this would, I believe, be a very serious mistake. I'm not going to buy a Nikon mirrorless if that means I have to start buying lenses all over again.

It is the other way around: like every previous case of a new mirrorless mount, it has a shorter flange depth than the maker's previous SLR mount and that means that an adaptor just needs to hold legacy SLR lenses the extra distance from the sensor (and pass through electrical signals). In this case, a "Z to F" adaptor would be about 29mm deep.

Link | Posted on Jan 12, 2018 at 20:00 UTC
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