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08-13-2013, 02:34 PM   #2491
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QuoteOriginally posted by goubejp Quote
The "fly by wire" in aircrafts has no mechanical backup. And if it fails the aircraft crashes, since the aircraft cannot be driven anymore. Since this system is used in civil aircrafts (beginning with Airbus A320 back in 1987) I have no knowledge that a failure of the system was the cause of a crash
The fly-by-wire system was identified as a contributing factor in the Air France A330 crash in the Atlantic Ocean. The pilot and first officer had input opposite corrective pitch commands without knowing what the other was doing. Wouldn't have happened with a standard yoke control.

BTW, my daughter is a private pilot and my son-in-law is a commercial aircraft pilot. Yes, they really look forward through the windscreen to take off, land, and for all ground movements. In fact, they absolutely have to be able to see the runway to land the plane.

08-13-2013, 02:34 PM   #2492
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But it has built-in redundancy, and it's made and maintained at other standards, than general consumer ones; even so, it's not failproof. I wasn't talking about it anyway.
Since you mentioned the A320, according to Wiki there are about 50 incidents in which it's electronic instrument display system failed - just for this plane. Of course, this is factored in during pilots training and even aircraft design; most essential instruments being redundant.

Last edited by Kunzite; 08-13-2013 at 02:42 PM.
08-13-2013, 07:09 PM   #2493
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QuoteOriginally posted by Asahiflex Quote
Yet TV cameras have recorded sports for ages *without any OVF*. How did they do that?
Real time? I don't think so. If I am tracking a flying bird, what I see in the viewfinder has to be instantaneous. Any lag means that the viewfinder is showing me what happened a short time ago, and I miss the shot.

This is a real technical challenge. In live view mode on my K5 manual focus is a chore due to the delay between updates. In the viewfinder, I turn the ring until it gets sharp then stop, maybe back up to make sure I haven't overshot. In live view the delay makes it certain I've overshot. I know the K5 updates are slow, and the latest evf's are quicker, but it illustrates the challenge. If it isn't close to instantaneous, it will cause a problem.

Whether the latest evf's are slow enough to cause a problem I don't know. But it is a real issue. I wouldn't buy one unless I could see whether there is any delay.
08-13-2013, 10:23 PM   #2494
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On the subject of EVFs Michael Reichmann of the Luminous landscape reviewed the Sony DEV-50 which is representative of the current generation of digital binoculars, in this review the biggest complaint about these digital binoculars were:

" ...users need to accept that looking at a video screen, even a beautiful high-res 2.3M dot pair of OLED eyepiece screens, is not as clear nor as bright as looking through a pair of decent optical binoculars."

And that is about a pair of digital binoculars - that use small sensors, and have dedicated video hardware (and also still photography feature). His other complaint was on the short battery life of the device, and that the battery has to be charged while it is inside the device.

I won't be throwing away my Carl Zeiss binoculars anytime soon.


Last edited by Digitalis; 08-13-2013 at 10:28 PM.
08-13-2013, 11:16 PM   #2495
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QuoteOriginally posted by Kunzite Quote
Because it applies sharpening?
How does an image get from the main sensor to the viewing screen in an EVF?

Is there something like conventional demosaicing (raw conversion); is there sharpening and/or other effects/filtering; is there even a JPEG (but not file) stage?
08-13-2013, 11:35 PM   #2496
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QuoteOriginally posted by IchabodCrane Quote
The fly-by-wire system was identified as a contributing factor in the Air France A330 crash in the Atlantic Ocean. The pilot and first officer had input opposite corrective pitch commands without knowing what the other was doing. Wouldn't have happened with a standard yoke control.

BTW, my daughter is a private pilot and my son-in-law is a commercial aircraft pilot. Yes, they really look forward through the windscreen to take off, land, and for all ground movements. In fact, they absolutely have to be able to see the runway to land the plane.
Isn't that the one where the person in the right hand seat was operating a mini side-yoke with his right hand, not observed by others in the cockpit? (A consequence of the Airbus side-yoke). I thought he "simply" kept it pulled back the whole time, (forcing the plane into a nose-up attitude, when they really needed nose-down for speed), rather than having input anything that the computer was acting upon? (I saw a reconstruction on TV based on the retrieved "black"-box recorder).

A difference between the cockpit of a plane and an EVF is that (I think) even the most modern cockpit isn't displaying the scene in front of the aircraft electronically. That view has to be obtained directly. (The thought of the pilot having no direct view, only an electronic view, in an aircraft is a bit scary to me as a passenger! If the power fails, there would no longer be any view! The consequences of a power failure in a camera are insignificant in comparison).
08-13-2013, 11:49 PM   #2497
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QuoteOriginally posted by Barry Pearson Quote
How does an image get from the main sensor to the viewing screen in an EVF?

Is there something like conventional demosaicing (raw conversion); is there sharpening and/or other effects/filtering; is there even a JPEG (but not file) stage?
Yes, there has to be a demosaicing step but I doubt they would be using JPEG internally (it would just add extra compression/decompression steps, with no real benefits). Processing the live stream is definitely possible, for example they are applying white balance to it.
I had a monitor (a cheap Samsung model) on which the sharpening was introducing annoying artifacts; fortunately it could be turned down from the menus.
08-14-2013, 12:20 AM   #2498
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QuoteOriginally posted by Digitalis Quote
On the subject of EVFs Michael Reichmann of the Luminous landscape reviewed the Sony DEV-50 which is representative of the current generation of digital binoculars, in this review the biggest complaint about these digital binoculars were:

" ...users need to accept that looking at a video screen, even a beautiful high-res 2.3M dot pair of OLED eyepiece screens, is not as clear nor as bright as looking through a pair of decent optical binoculars."

And that is about a pair of digital binoculars - that use small sensors, and have dedicated video hardware (and also still photography feature). His other complaint was on the short battery life of the device, and that the battery has to be charged while it is inside the device.

I won't be throwing away my Carl Zeiss binoculars anytime soon.
Ok, now we're comparing cameras, airplanes and binoculars. Three completely different tools. That's a bit wonky, to put pollitely. It does bring a good point to the surface though.

The primary function of a pair of binoculars is enlarging a far away image and displaying it to the user as best as possible. The experience of that viewing is very important as it is the main feature. In that respect: I have no idea what electronic displays are doing in a pair of binoculars? I guess someone somewhere had to try it.

Now the primary function of a camera is something very different: Surprise - surprise! It's capturing images. The VF or LCD display is merely there to assist the user in capturing those images. And here is where the EVF is doing a much better job then the OVF. It displays during video recording, displays focus peaking, displays zooming during focussing, better low light performance, and can display a large customizable collection of other helpfull information. (Especially with Pentax excellent backwards compatibility the EVF should be very highly appreciated.) Moreover, with an EVF, there's no need for a bouncing mirror that hammers the IQ out of those images.

What I'm saying is, if the viewing experience is so very important to someone that they are prepared to sacrifice image capturing functionality and quality for that, then they are better off with a pair of optical binoculars instead of a camera.

08-14-2013, 12:37 AM   #2499
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QuoteOriginally posted by Clavius Quote
The VF or LCD display is merely there to assist the user in capturing those images. And here is where the EVF is doing a much better job then the OVF
I think you're missing the point - Michael Reichmann, a highly skilled photographer who is also quite knowlegable on photographic optics is complaining that the current generation EVFs aren't as bright and clear as an optical pair of binoculars would be. Clavius, you seem to be suggesting that EVF's are better than Optical viewing systems - but with this current sony product: a pair of electronic binoculars this is clearly not the case.

You seem to be more concerned with how many gadgets and manual focusing aids you can display on the cameras EVF rather than the actual usefulness of the display in rendering the scene to be captured. I personally prefer un-clutterd OVFs. There were some SLR cameras in the late 90's that had LED light shows going on in the viewfinder that were far to distracting ( for me). Also bear in mind that mirror vibrations aren't as detrimental to image quality as you suggest.They are able to be controlled, also shutter mechanisms introduce vibrations as well.

Last edited by Digitalis; 08-14-2013 at 12:44 AM.
08-14-2013, 01:52 AM   #2500
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QuoteOriginally posted by Digitalis Quote
You seem to be more concerned with how many gadgets and manual focusing aids you can display on the cameras EVF rather than the actual usefulness of the display in rendering the scene to be captured.
Actually, I'm MORE concerned with the latter. In my opinion, EVF and LCD's render the scene more correctly. OVFs are prone to being out of sync with the lens focus, in other words, they need to be calibrated. Moreover the size seems less, even though some cameras are claimed to have 100% viewfinders. And then there's the small size and lack of brightness of the OVF, which cannot be larger or brighter then the given format.

Peering down the same lenses through the NEX7 gives me a much better impression of the scene to be captured. Larger, brighter, more accurate, never prone to calibration issues, no figetting with after market focussing screens and shims. (Which often only result in dusty screens and/or VF optics.)

[SARC]
And don't get me started on how well the OVF renders during video mode.
[/SARC]

There's a serious note to that last sarcastic line though. I'm more and more confronted with clients asking me to do video, regardless of the fact that I in no way advertise or offer that service. Video is not my interest at all, but I can't keep saying no to clients. I've not a few now and the clients are very happy with the results. But being able to do both with the same body and same set of lenses would be magic.


QuoteOriginally posted by Digitalis Quote
I personally prefer un-clutterd OVFs. There were some SLR cameras in the late 90's that had LED light shows going on in the viewfinder that were far to distracting ( for me). Also bear in mind that mirror vibrations aren't as detrimental to image quality as you suggest.They are able to be controlled, also shutter mechanisms introduce vibrations as well.
Agree 100%: this is all very personal. A is better for you, B is better for me, C will be better for who knows who. It's human nature.

Facts are:
1. There is still no pro or prosumer -level ILC with a good EVF to choose.
2. Including the used market, there are now hundreds of different DSLR models to choose from. And they're not going anywhere soon.
3. The EVF-discussion comes up in MANY topics, not only here on PF, but on Canon and Nikon forums alike. So it appears that there's enough people that want one.

Last edited by Clavius; 08-14-2013 at 01:57 AM.
08-14-2013, 01:54 AM   #2501
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QuoteOriginally posted by Clavius Quote
I'm comparing the small dark VF of my K-5 and 5DMKII with the large and bright VF on my NEX7.
It might be large and bright, but I know for sure I wouldn't trade it for my K-5's OVF...
08-14-2013, 02:28 AM   #2502
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QuoteOriginally posted by Digitalis Quote
You seem to be more concerned with how many gadgets and manual focusing aids you can display on the cameras EVF rather than the actual usefulness of the display in rendering the scene to be captured. I personally prefer un-clutterd OVFs. There were some SLR cameras in the late 90's that had LED light shows going on in the viewfinder that were far to distracting ( for me). Also bear in mind that mirror vibrations aren't as detrimental to image quality as you suggest.They are able to be controlled, also shutter mechanisms introduce vibrations as well.
I would like two modes: uncluttered much of the time, but with an option to add extra information in a very easy way, for example by pressing an easy to use button.

When I look through the viewfinders of my Pentax film SLRs, from the SP500 to the Z1-p, I see a gradual increase in the amount of extra information combined with a gradual reduction in the size of the image itself. I guess the two are related - adding extra information around the image in my earlier cameras would stop me being able to see everything, so Pentax gradually changed the magnification accordingly.

This suggests that what I need is an image that is as large as I can see with spectacles, used for accurate framing, and an overlay onto that image (not around it) at the touch of a button. This isn't a stopper for OVFs - after all, they can overlay AF indicators. But I suspect it would be easier to achieve with EVFs.

(I know professional photographers who claim that even 2 seconds isn't enough for mirror-induced vibrations to cease. It appears to be enough for me).
08-14-2013, 03:15 AM   #2503
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QuoteOriginally posted by Kunzite Quote
Yes, there has to be a demosaicing step but I doubt they would be using JPEG internally (it would just add extra compression/decompression steps, with no real benefits). Processing the live stream is definitely possible, for example they are applying white balance to it.
That makes sense. (And presumably the feed from the main sensor has to be downsized to match the EVF screen?)

I was misled by (perhaps misinterpreted) "Why Moore's Law Applies to Photography". It says:
"High transistor densities translate directly into higher computing power onboard the camera. For JPEG quality, not just for JPEG output but also LCD preview in the field, live-view, electronic viewfinders and movie recording which are all dependent on the JPEG engine. This includes more sophisticated noise processing engines in all these modes."

"Using the JPEG engine" doesn't necessarily mean "using JPEG". There must be lots of functionality in that engine other than conformance to JPEG.

Last edited by Barry Pearson; 08-14-2013 at 03:26 AM.
08-14-2013, 03:46 AM   #2504
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QuoteOriginally posted by Barry Pearson Quote
Isn't that the one where the person in the right hand seat was operating a mini side-yoke with his right hand, not observed by others in the cockpit? (A consequence of the Airbus side-yoke). I thought he "simply" kept it pulled back the whole time, (forcing the plane into a nose-up attitude, when they really needed nose-down for speed), rather than having input anything that the computer was acting upon? (I saw a reconstruction on TV based on the retrieved "black"-box recorder).

A difference between the cockpit of a plane and an EVF is that (I think) even the most modern cockpit isn't displaying the scene in front of the aircraft electronically. That view has to be obtained directly. (The thought of the pilot having no direct view, only an electronic view, in an aircraft is a bit scary to me as a passenger! If the power fails, there would no longer be any view! The consequences of a power failure in a camera are insignificant in comparison).
IIRC, it was the other way around. The PIC (pilot in charge... left seat) was wrongly pulling up on his joy stick while the first officer (right seat) was correctly pushing down on his joy stick. All studies/reviews point to the FO having no idea that the PIC was inputing the wrong command.
08-14-2013, 03:48 AM   #2505
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QuoteOriginally posted by Clavius Quote
The EVF-discussion comes up in MANY topics, not only here on PF, but on Canon and Nikon forums alike. So it appears that there's enough people that want one.
Just because many people are talking about producing a high level EVF based camera body doesn't give the idea merit. Current EVF based Mirrorless cameras haven't been selling all that well...at least compared to traditional SLRs.

QuoteOriginally posted by Clavius Quote
OVFs are prone to being out of sync with the lens focus, in other words, they need to be calibrated.
I calibrate my own RF cameras and SLR cameras, I wet clean the sensor and clean the mirror box - I consider it part of the basic setup of a new camera when I buy it, especially when I plan to use manual focus lenses with it. As a working professional I consider it mandatory for all the cameras I buy.
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