malcolm82

malcolm82

Lives in United Kingdom United Kingdom
Joined on Sep 17, 2005

Comments

Total: 187, showing: 21 – 40
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In reply to:

toughluck: In terms of DOF, it's a 50/9 equivalent, so good luck trying to get meaningful defocusing. It should have been f/1.2 or f/0.9 for the size -- while it would still have poor defocusing control, it would have been much better.

Also: Why is the lens and the bodies so huge? Sony just released RX1 which, lens included, is thinner than this lens is long. Not to mention huge N1 bodies.

"You can use medium format lens on 35mm camera without light loss (you are just cropping the centre part of the imaging circle), but You cannot do the same in opposite direction."
You are cropping the lens which means you are losing light obviously... What do you think is happening to all that light not hitting the small sensor? It is not being put to very good use is it?

Direct link | Posted on Sep 14, 2012 at 06:49 UTC
In reply to:

toughluck: In terms of DOF, it's a 50/9 equivalent, so good luck trying to get meaningful defocusing. It should have been f/1.2 or f/0.9 for the size -- while it would still have poor defocusing control, it would have been much better.

Also: Why is the lens and the bodies so huge? Sony just released RX1 which, lens included, is thinner than this lens is long. Not to mention huge N1 bodies.

I did not ask any question. I was illustrating equivalence by pointing out that not only are small format lenses equivalent to higher F larger format lenses but they are actual higher F lenses when used on the larger formats as a macro lens. Equivalence is about total exposure or amount of light captured and not light density which is irrelevant.

Direct link | Posted on Sep 14, 2012 at 06:44 UTC
In reply to:

toughluck: In terms of DOF, it's a 50/9 equivalent, so good luck trying to get meaningful defocusing. It should have been f/1.2 or f/0.9 for the size -- while it would still have poor defocusing control, it would have been much better.

Also: Why is the lens and the bodies so huge? Sony just released RX1 which, lens included, is thinner than this lens is long. Not to mention huge N1 bodies.

This lens would make a great macro lens when used reversed on a 5x4 large format camera. It would be an F/17 and image a 12.8x9.6mm area with the same image quality as you get using this lens on the 1 system for normal photography.

Direct link | Posted on Sep 13, 2012 at 22:51 UTC
In reply to:

toughluck: In terms of DOF, it's a 50/9 equivalent, so good luck trying to get meaningful defocusing. It should have been f/1.2 or f/0.9 for the size -- while it would still have poor defocusing control, it would have been much better.

Also: Why is the lens and the bodies so huge? Sony just released RX1 which, lens included, is thinner than this lens is long. Not to mention huge N1 bodies.

Not only is this lens equivalent to 50mm f/4.9 but you can actually use this exact lens on a full frame sensor with the exit pupil of the lens 2.7x the distance from the sensor surface as it is on a nikon 1 body. This will give you a 50mm f/4.9 macro lens. So does the lens magically capture more light by using it on a smaller sensor?

Direct link | Posted on Sep 13, 2012 at 22:42 UTC
In reply to:

Jan Kritzinger: My only complaint is that the lens is slightly bulky for the body form factor - give us a 23/2.8 APS-C RX10 the size of the RX100, for $1k! Come on Sony, Do it!

A 23/2 lens for aps-c can easily fit in the RX100, I am sure it could be made significantly smaller actually, so why would you want a 2.8?
The only reason this RX1 is so big is because the lens is not retractable, it could be less than 50mm in depth with a retractable lens.

Direct link | Posted on Sep 12, 2012 at 17:53 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

Exactly. Cy Cheze do you always keep your eyes fixed exactly on the center of your display?

Direct link | Posted on Aug 3, 2012 at 15:49 UTC
In reply to:

AndyGM: This is a good summary of the work NHK have done:

http://www.nhk.or.jp/strl/english/aboutstrl1/r1-1-1.htm

Figure 2 is very interesting, it is demonstrating the results of 2 "perception tests" they have carried out using 8K displays.

The 2 perceptions they have tested are "sense of realness" and "sense of being there". If you sit closer to the screen, it fills more of your field of view so your sense of being there goes up, but you might start to be able to see the pixels in the image, so your sense of realness goes down.

The sense of being there stops scaling linearly at about 70deg FOV, this is a point of diminishing returns. This is also roughly where the 2 lines cross (where the sum of both perceptions is at a maximum). This corresponds with a viewing position somewhere between 1 and 1.5 times the picture height. I will leave it to Randomoneh to work out how many Pixels/deg this is, but its still more than enough for most people to not see individual pixels.

"OK, the work done by NHK is answering those that say human eyesight is 30 CPD (aka 60 pixels per degree), so any screen that provides more than that is a waste."

The reason that this is false is because a display with 60 pixels per degree can only display 60 lines per degree if the lines are exactly aligned with the pixel grid, if they are not they can disappear completely. Even if you have 600 pixels per degree there will still be a drop in contrast for 60 lines per degree displayed but with exact contrast compensation (or sharpening) 120 pixels per degree can be enough to consistently accurately display 60 lines per degree.

Direct link | Posted on Aug 3, 2012 at 15:28 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

@Randomoneh
I found a few articles and also saved a PDF. :)
It is close to my own estimates, what Apple calls retina looks very good but is still obviously lacking for small detail, 1.5x retina can be indistinguishable from perfect on most images while 2x retina given proper sharpening can be perfect on nearly anything in practice. 7680x4320 approximately meets the 1.5x point for a 28mm equiv 75° field of view which is why i consider that a minimum for a truly high quality display for a decent field of view. Too bad 3840x2160 is yet to be released...

Direct link | Posted on Aug 2, 2012 at 02:52 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

Thanks.
I just found you on this forum:
http://forums.macrumors.com/archive/index.php/t-1380708.html

small internet :)

Direct link | Posted on Aug 1, 2012 at 22:26 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

@KitHB
I found something about that bbc research you mentioned:
http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP169.pdf
I wish this stuff was common knowledge among so called video 'experts'.

The picture at the bottom shows how bad 50fps still is, i see this blurring all the time on 50fps broadcasts on eurosport and bbc.

Direct link | Posted on Aug 1, 2012 at 21:36 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

Yes you are right, and because of this i think that for 90° fov and bigger flat displays get quite absurd and a curved one would be much more suitable. Personally I am looking to use 75° diagonal fov as my standard view for a flat display when they are good enough which would match the diagonal fov of a 28mm full frame lens.
For a 100" display that is a viewing distance of 64.7" so it is not really realistic to expect more any time soon both because of the size and limited resolution.

Direct link | Posted on Aug 1, 2012 at 20:57 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

@KitHB
What did you think about the reactions to the 48fps used in The Hobbit? I also read some discussion somewhere about which frame rate would be the future of cinema: 48fps vs 60fps. It is really sad to see.

I am hoping to get a 7680x4320p300 display very soon. Anything lower is just no good.

Direct link | Posted on Aug 1, 2012 at 20:44 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

@KitHB
I agree and I consider higher frame rates to be more important than higher resolution especially for current display sizes and because of the very low frame rates used. Depth of field limitations will also prevent getting the full benefit from very high resolutions.

However I do not agree that 300fps is high enough. Motion blur at that speed will still cause a very obvious reduction in resolution. To achieve perfect sharpness on moving subjects the motion blur caused by both the exposure time and the display hold time needs to be reduced to about the size of a single pixel. For 8k displays when panning at 1 display width per 2 seconds this means 1/4000th exposure time and display time which means that with continuous capture and display we will need 4000fps. Capturing at a much slower frame rate with this same high shutter speed and strobing the display can achieve almost the same result but has limitations which mean that eventually these very high frame rates will be used.

Direct link | Posted on Aug 1, 2012 at 20:35 UTC
In reply to:

malcolm82: From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

@mister_roboto
You only see a 60° field of view? That is very narrow, most of us see over 180° and it is actually possible to rotate your head to look around too.

For a 90°+ field of view a flat display with uniform pixel density would need about 4 times the pixel resolution of these displays or 15360x8640 to be good enough in the center of the field of view.

Imax classic theaters have approximately this field of view for the middle seating position:

http://www.lfexaminer.com/20090522a.htm

“The high-resolution picture is used in conjunction with a large screen and carefully organized audience seating to ensure that minimum and maximum viewing angles lie between 60° to 120° horizontally and 40° to 80° vertically for the farthest and nearest spectators respectively. The intent is to create an illusion of ‘being there,’ rather than present a ‘normal’ motion picture through a well-defined window.

Direct link | Posted on Aug 1, 2012 at 20:15 UTC

From Engadget:
"Ultimately, there's plenty of reason to believe the BBC's project head, Tim Plyming, when he says that "8K is the maximum the human eye can understand" and that "it's the end of the resolution story.""

That's only true for a field of view equivalent to about 40mm (or about 55-60° diagonal). For ultra wide angle viewing we need much higher.

Direct link | Posted on Aug 1, 2012 at 17:53 UTC as 19th comment | 18 replies
On Just Posted: Nokia 808 PureView Review article (210 comments in total)
In reply to:

Simon97: Interesting technology. I can see this combine with perhaps a 2 or 3x zoom lens so that pixel count does not need to be reduced as much with zooming and lens quality not sacrificed as well. The images here are much better than the current crop of 16mp compacts that are just atrocious.

Dynamic range is my only concern. It won't be adopted by serious shooters with that highlight clipping issue.

The prime lens is the reason it can have image quality this good in this size, a zoom lens would ruin it.

Direct link | Posted on Jul 31, 2012 at 01:24 UTC
In reply to:

acid592: Some members wrote as if f value is related to sensor size (if i understand right). I think f 1.4 always gets in more light than f 1.8 independent of the sensor size. Right?

Yes it is the combination of ISO and sensor area that determines the image quality, not ISO on its own. The RX100 sensor collects roughly the same amount of light at ISO 350 as the LX7's active sensor area does at ISO 100.

Direct link | Posted on Jul 31, 2012 at 01:14 UTC
In reply to:

Tom Goodman: Smaller sensor. Forget about it. Faster lens. How often does anyone really need that? Go on, count the number of shots you've done in the last month that needed the faster lens. It isn't going to give you DOF flexibility either.

"Keeping ISO at 100 offers no significant advantage over bumping it up to 200 0r 250 and forces you to use apertures that are not optimal."

This is true for larger sensors of m43 and above but not for the sensor size of this camera so i agree with Michael_13 that being able to shoot wide open to keep iso as low as possible is crucial on compacts. Of course as you say the quality benefit is lost if the lens loses resolution wide open.

Keep in mind that this lens wide open is only F7 equivalent, it is still a very small aperture which cannot be considered the same as F1.4 on full frame.

Direct link | Posted on Jul 22, 2012 at 02:50 UTC
In reply to:

malcolm82: Again with a horrible F1.4 lens.
A camera this size with a normal zoom should have an aps-c sensor with a lens of around F3.5-5.6 such as the standard zooms on interchangeable lens camera's.

Just look at the size of the panasonic powerzoom lens:
http://www.dpreview.com/previews/panasonic_x_14-42_3p5-5p6/2

Its total length looks about 32mm so it can easily collapse in a camera size much smaller than this one.

A micro four thirds sensor would be ok for a camera this size with a 5x zoom lens or for a much smaller camera with shorter zoom range but for this size with 3-4x zoom it really should be aps-c.

Ill quote professor999:

"HowaboutRAW,

In fact, each time someone disagrees with you you move the goalposts. I throw cold water on your hypothesis and you scramble to find another which will hold water."

Direct link | Posted on Jul 21, 2012 at 23:55 UTC
In reply to:

malcolm82: Again with a horrible F1.4 lens.
A camera this size with a normal zoom should have an aps-c sensor with a lens of around F3.5-5.6 such as the standard zooms on interchangeable lens camera's.

Just look at the size of the panasonic powerzoom lens:
http://www.dpreview.com/previews/panasonic_x_14-42_3p5-5p6/2

Its total length looks about 32mm so it can easily collapse in a camera size much smaller than this one.

A micro four thirds sensor would be ok for a camera this size with a 5x zoom lens or for a much smaller camera with shorter zoom range but for this size with 3-4x zoom it really should be aps-c.

"And a second preposterous claim by you: That F1.4 lenses are horrible."

What exactly was my first preposterous claim again? The one that you imagined i made?

Direct link | Posted on Jul 21, 2012 at 23:51 UTC
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