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08-13-2013, 02:17 AM   #2476
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QuoteOriginally posted by Uluru Quote
Let's play mathematics. How many years it would need for EVFs to match the resolution and frame rate of the good OVFs?
When I look down the VF of my K-5 or 5DMKII, I don't see much of that unlimited resolution. Why is that? I'll tell you why: There's focus screen, prism, mirror and VF optics in between the lens and my eye. Those parts can only subtract light from the path, they can never add any light. But moreover, the focus screen introduces a kind of grain to the image in the VF. The matte microprisms are responsible for that. That is why the OVF of my K-5 looks more like a miniature tv-screen, then the EVF on my NEX7. That is why to my eye the NEX actually seems to have a higher resolution, while technically that would be impossible.

Really, the only thing the OVF is unbeatable at is the speed, which comes in very handy for sports photography.


Last edited by Clavius; 08-13-2013 at 02:30 AM.
08-13-2013, 03:11 AM   #2477
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QuoteOriginally posted by Clavius Quote
Really, the only thing the OVF is unbeatable at is the speed, which comes in very handy for sports photography.
Yet TV cameras have recorded sports for ages *without any OVF*. How did they do that?

Of course, there is too much processing going on in our digital still cameras with Live View, causing lag. But that problem can and will be solved soon (if it's not solved already). And isn't it true that most, if not all, TV and film makers use EVS's 99,99% of the time now that they've gone mainly digital?

It's good to know that I'm VERY old-fashioned with regards to cameras and lenses. But even I am not entirely convinced of the virtues of an OVF because of its inherent drawbacks (and there are many: they show things sharp which simply aren't in focus, they need to be calibrated with the AF assembly and the sensor/film plane, etc. Try focusing a f/1.2 lens with a current OVF!). Despite the drawbacks of EVF's (power consumption and low resolution being perfect examples) I think it's just a matter of years before the last DSLR with OVF will be discontinued. Unless... they find a way to make the OVF like it was in the 70's. Truth be told, the OVF's of my Pentax MX and LX put ANY current DSLR to shame with regards to their sheer size and focusability.

So, my opinion is simple. OVF's must take a few steps backwards, and EVF's a few steps forward. Then both systems can be a perfect choice depending on the intended usage/user.
08-13-2013, 03:17 AM   #2478
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QuoteOriginally posted by Clavius Quote
When I look down the VF of my K-5 or 5DMKII, I don't see much of that unlimited resolution.
That is probably because you are limited by the resolution of your lens, also slower lenses make the grain on the ground glass stand out more. Bear in mind that physics puts finite limits on resolution, and the human eye can only resolve so much detail - and those limits change from person to person, age is also a factor.

Speed is going to be a limiting factor with EVFs - though I consider colour depth and dynamic range to be far more problematic. With DSLR sensors being 14-bit devices with a massive gamut, EVFs have bandwidth limitations to overcome when handling such huge amounts of data at high transmission rates. With an increase in bandwidth - there will be increased heat generated due to processor overhead and reduced battery life.

Last edited by Digitalis; 08-13-2013 at 03:29 AM.
08-13-2013, 03:22 AM   #2479
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QuoteOriginally posted by Digitalis Quote
That is probably because you are limited by the resolution of your lens...physics puts finite limits on resolution, and the human eye can only resolve so much detail - and those limits change from person to person, age is also a factor.
You make it sound as if a ground glass screen shows unlimited resolution, which simply is untrue. Most ground glass screens are coarse (though not always visible) and this puts a limit on visible resolution.

08-13-2013, 03:39 AM   #2480
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QuoteOriginally posted by Digitalis Quote
That is probably because you are limited by the resolution of your lens, also slower lenses make the grain on the ground glass stand out more. Bear in mind that physics puts finite limits on resolution, and the human eye can only resolve so much detail - and those limits change from person to person, age is also a factor.
It appears you picked just one line from my post to read an react on, whilst totally ignoring the rest.

It can't by my eyes, age lenses. If it was, then why does my NEX7 show much sharper - if not crystal clear- image, using the SAME lenses and the SAME eyes?
08-13-2013, 03:47 AM   #2481
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QuoteOriginally posted by Clavius Quote
It appears you picked just one line from my post to read an react on, whilst totally ignoring the rest
well you have done the same, and I was just highlighting the primary criticism you have of optical viewfinders* - for my work OVFs get the job done, especially with all the different formats I work with - you may think differently, and you are entitled to that.

*incidentally, the focusing screens used in modern DSLR cameras these days do not have microprisms on them - they are just simple Fresnel screens.
08-13-2013, 04:42 AM   #2482
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QuoteOriginally posted by Clavius Quote
It can't by my eyes, age lenses. If it was, then why does my NEX7 show much sharper - if not crystal clear- image, using the SAME lenses and the SAME eyes?
Because it applies sharpening?
08-13-2013, 05:52 AM   #2483
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Yeah, I saw that while I was riding and shooting the V1 in the Vermont woods. No matter, the camera performed like a champ, and now I'm contemplating a second body and more lenses. If anything, the deeper DOF works for the kind of travel photography that I do because it allows me to keep the subject in the context of its surroundings without having to stop down too much.

This one shot alone shows how good the V1's AF is:




There is OOF areas with the 1" sensor and the longer focal length, and there are many things that the camera could have misfocused on. But the V1 nailed it.

Here's a little more of the story:

What Blog is This?: Go Figure (The Continuing Adventures of the Nikon V1)

At this point, I see no reason to take the K-5 on trips. I miss the stellar usability and the awesome files and the level and other things, but the little V1 is the right compromise of features and liabilities right now. And here's my attempt to bring this thread back on track...

I hope the K-3 has AF as good as the V1 and good video too. That may put Pentax back in my bag on trips like this.

08-13-2013, 06:01 AM   #2484
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QuoteOriginally posted by Kunzite Quote
Glass cockpits... aren't those some sort of optical viewfinders?
A friend of a friend took me for a ride in his four person plane. My very first reaction upon sitting in the passenger seat was, "The instruments and dashboard are so big that I can't see out of the front of the plane!" Yes there was a window on front, but all you could see was stuff 30 degrees above horizontal; it was nothing like being in a car. The pilot did look out the side window from time to time, but it was quite clear that he was flying by instruments and looking out the side window for visual confirmation of what the instruments and traffic control were telling him.
08-13-2013, 06:19 AM   #2485
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QuoteOriginally posted by johnmflores Quote
A friend of a friend took me for a ride in his four person plane. My very first reaction upon sitting in the passenger seat was, "The instruments and dashboard are so big that I can't see out of the front of the plane!" Yes there was a window on front, but all you could see was stuff 30 degrees above horizontal; it was nothing like being in a car. The pilot did look out the side window from time to time, but it was quite clear that he was flying by instruments and looking out the side window for visual confirmation of what the instruments and traffic control were telling him.
Right but is it because the plane has a 'OVF of some kind' (e.g. a window but with lots of instruments in the way) or because doing othetrwise would break the standard placement for such (or all) planes, useability contraints or safety considerations (that all instruments must exist in hard, real and not only on a screen).

I for one would really be nervous if I had to fly a plane or ride a car which has NO mechanical instruments and only 'computerized' ones.
It'd be funny to see people drive with an electronic steering wheel. In fact, if it wasn't dangerous, It'd be hilarious.
Maybe one day. Why not, but now? ROTFLMAO.
08-13-2013, 06:24 AM   #2486
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30 degrees is a lot, assuming that the plane's position was pretty much horizontal. Was it a tail wheel plane, by chance?
I'm not trying to build yet another bad analogy with the camera viewfinders; there are too many differences (for example, we don't need as many instruments, nor do we shoot by instruments ). But as long as there will be a pilot inside, the cockpit's "optical viewfinder" will stay.
08-13-2013, 07:22 AM   #2487
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QuoteOriginally posted by thibs Quote
Right but is it because the plane has a 'OVF of some kind' (e.g. a window but with lots of instruments in the way) or because doing othetrwise would break the standard placement for such (or all) planes, useability contraints or safety considerations (that all instruments must exist in hard, real and not only on a screen).
I'm no pilot so maybe someone else with real knowledge can contribute.

QuoteQuote:
I for one would really be nervous if I had to fly a plane or ride a car which has NO mechanical instruments and only 'computerized' ones.
It'd be funny to see people drive with an electronic steering wheel. In fact, if it wasn't dangerous, It'd be hilarious.
Maybe one day. Why not, but now? ROTFLMAO.
We're already there:

Take a Look Inside the First Steer-by-Wire Car | Autopia | Wired.com

Most cars these days have electric-assisted steering vs. the older hydraulic assist because electric systems are lighter and cheaper. And more and more motorcycles have ride-by-wire throttles where the twist grip is simply a potentiometer. The signals from the potentiometer get sent to the bike's computer, which then decides based on a number of factors - speed, riding mode, etc - how to convert that to engine power.
08-13-2013, 07:25 AM   #2488
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QuoteOriginally posted by Kunzite Quote
30 degrees is a lot, assuming that the plane's position was pretty much horizontal. Was it a tail wheel plane, by chance?
I'm not trying to build yet another bad analogy with the camera viewfinders; there are too many differences (for example, we don't need as many instruments, nor do we shoot by instruments ). But as long as there will be a pilot inside, the cockpit's "optical viewfinder" will stay.
This was a number of years ago but yes I think it was a tail wheel plane. I do remember being in the air and not being able to see over the instruments.
08-13-2013, 09:41 AM   #2489
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Even that Infinity prototype has a backup mechanical link to the wheels. It has to, as electric systems can fail (and by the way, this happened with planes)

The electric power steering is just an electric motor assisting the mechanical steering system; it might be cheaper and less power hungry, but the car makers are struggling to make one which isn't bland and uninspiring.
The "throttle by wire" system is indeed electrical, very reliable despite claims to the contrary, and its failure is not usually a safety issue as the engine would go idling. It's not just a potentiometer, that would fail; instead, dual HAL effect sensors are used (with a mechanism to detect failures).
My car has both systems; and by the way - it's a Toyota, a brand unfairly bashed for an accelerator pedal issue. During the long fight to prove them guilty no matter what, the only way to make the accelerator's electric system misbehave was sabotage.

About that plane, I doubt all of them are that bad. OTOH, there's only so much space to put all the instruments...

Of course, this has nothing to do with camera viewfinders.

Last edited by Kunzite; 08-13-2013 at 09:48 AM.
08-13-2013, 02:15 PM   #2490
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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
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