BJL

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

Comments

Total: 279, showing: 61 – 80
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In reply to:

falconeyes: Ok, the RWB Bayer CFA is real, I researched it a bit.

If anybody wonders how it can work, well, the green channel can be easily computed from white when already knowing the red and blue channels. However, there is a problem with increased color noise (because the color matrix now contains large negative factors -- the difference of two noisy signals is an even noisier one) and early saturation of the white pixels. At least, conventional demosaicsm applies with just a modified color matrix table. Converters should have no problem to support it.

I found a 2006 research paper where Samsung discusses their ideas related to the RWB Bayer CFA:

-> http://www.jsts.org/html/journal/journal_files/2006/12/08%28271-275%29.pdf

That reference proposes a method to avoid blown out white pixels: read the charge in each white pixel partway through the exposure and again at the end (without reset?) Then combine the two readings, or just extrapolate from the first one if the later one is blown out.

Link | Posted on Jul 31, 2015 at 14:25 UTC
In reply to:

joe6pack: 5mm for a sensor is thin?

What about the lenses? And the screen in the back? All that has to fit under 7mm.

5mm is the whole camera module height, from back of sensor to front of lens: that is the height that has been thinned down.

Link | Posted on Jul 31, 2015 at 14:13 UTC
On article The big beast: hands on with the Panasonic Lumix DMC-GX8 (1290 comments in total)
In reply to:

AbrasiveReducer: All this technology. But it seems that when they try to get the best quality from a compact camera it still ends up pretty big.

I agree with the above two replies: as a telephoto photography enthusiast, I like bodies just big enough to provide a good handgrip (also comfortable for carrying the camera one-handed with a long lens attached) and controls that are not too small, too few or too close together.

The smaller format size advantage comes in the shorter focal length _lenses_ need for a given telephoto reach. This is helped by having an abundant pixel count, to allow loose framing and cropping.

For those priorities, this new body, its 20MP 4/3" sensor, and the new 100-400 lens are very appealing. (I like the Olympus OMD EM1 in hand too, but have only tried it in shops so far.)

Link | Posted on Jul 16, 2015 at 20:02 UTC
On article Sony rides wave of US Mirrorless sales surge (727 comments in total)
In reply to:

BeaverTerror: Mirrorless is the official term now? So instead of choosing a term which describes the camera, they have moronically chosen a term describing what the camera does not have. One day DSLRS will be a nostalgic memory and we will still be stuck with "mirrorless". Same situation as clipless bicycle pedals.

Genius.

We have settled on "wireless" for computer networking connections that do not require wires, so I can see "mirrorless" (and its claim to reduce the bulk, vibration, shot-to-shot lag etc, that a flipping mirror and pentaprism add) staying around for a while.

Link | Posted on Jun 4, 2015 at 16:21 UTC
In reply to:

mosc: So, I have a question. This sensor is 0.64x crop correct? Are the lenses made specifically at that crop? It's awfully close to the old 6x4.5 film format. I'm wondering if the lenses cover the area of 6x4.5 or if they're specially made for this sensor size?

It is bizarre to described this as a "crop" of the smaller 36x24mm format. The 60MP and 80MP sensor options are 53.7 x 40.4mm, so 67mm diagonal, very slightly less than the 70mm diagonal of the 56x42mm so-called "645" film camera format. Despite the inaccurate name, "645" format was never 60x45mm,
and slide mounts knocked a few mm off that.

And yes, the lenses used are designed for that 70mm diagonal "645" format.

Link | Posted on Jun 2, 2015 at 18:59 UTC
In reply to:

Tungsten Nordstein: 'If successful the algorithm may have serious consequences for the flexible rubber lens hood market, though early indications suggest polarizing filter manufacturers will be safe for some time to come.'

I'm so glad the main concern here is for possible effects on industry and commerce rather than the implications for personal privacy.

Tungsten, this was obviously a joke -- at least to anyone who remembers that jokes were not always automatically followed by a smiley face.

Link | Posted on May 19, 2015 at 19:10 UTC
On article Panasonic Lumix DMC-G7 offers 4K video (130 comments in total)
In reply to:

mpgxsvcd: I am not seeing a lot to dislike about this camera. They would sell a lot more of these if they advertised them more and also sold them in stores like Best Buy right from day one. As it stands right now Canon will sell many times as many T6s/T6i cameras as Panasonic will sell G7 cameras.

That is also despite the fact that the Canon cameras had a significant defect in a large portion of their initial shipments(Which they addresses quickly), the T6s only does 5 FPS vs. the 7 FPS for the G7, The G7 is cheaper, and the G7 does 4K @ 30 FPS video vs just 1080p @ 30 FPS for the Canon cameras.

Panasonic’s issue is not that they don’t make great cameras. There issue is that not enough people even know they make cameras.

@neez: "Actually hard drives are downsizing because they are switching from optical drives to SSD."
No one is being forced to abandon a larger hard drive in favor of a smaller SSD, and people who want to store a lot of video, photos and such can easily opt for a large capacity, or an SSD/HD combo. With Macs at least there is also the option of a fusion drive: basically a larger capacity hard drive combined transparently with a smaller capacity SSD, keeping the stuff that benefits most from speed on the SSD part.

So, no: there is not the slightest sign of a trend towards people have less access to large storage capacity on their personal computers if they want it!

Link | Posted on May 18, 2015 at 22:17 UTC
On article Panasonic Lumix DMC-G7 offers 4K video (130 comments in total)
In reply to:

mpgxsvcd: I am not seeing a lot to dislike about this camera. They would sell a lot more of these if they advertised them more and also sold them in stores like Best Buy right from day one. As it stands right now Canon will sell many times as many T6s/T6i cameras as Panasonic will sell G7 cameras.

That is also despite the fact that the Canon cameras had a significant defect in a large portion of their initial shipments(Which they addresses quickly), the T6s only does 5 FPS vs. the 7 FPS for the G7, The G7 is cheaper, and the G7 does 4K @ 30 FPS video vs just 1080p @ 30 FPS for the Canon cameras.

Panasonic’s issue is not that they don’t make great cameras. There issue is that not enough people even know they make cameras.

@neez says that "less than 1% of the population owns 4k TV's or 4k monitors, so 4k is useless to most people. Plus most people buy laptops ..."
Apart from the trend to ever cheaper 4K TV's, those laptops along the desktop computers that lots of people also still buy are already moving to screen resolutions beyond the 1920x1080 of HD TV, so 4K video will already look better on many computer screens, which is where many of us watch videos these days. Those computers are also acquiring ever more and cheaper mass storage, both onboard and with the option of external drives for those with big photo/video collections, so the "not enough storage space for higher definition images" fails, as it has repeatedly.

Link | Posted on May 18, 2015 at 16:19 UTC
In reply to:

J A C S: The 8mm is about 10% longer than the Canon 15mm, the same width and a few grams lighter only. More expensive and collects less light.

Similarly, the 7-14 is 23mm longer than the Canon 8-15; width and weight about the same, 1 stop less light, same price.

What happened to the portability of the m43 system?

"Cheaper - no. There are FF bodies for ~$1,200" and there are MFT bodies with EVF for $450 (E-M10). Or are you for some reason comparing the cheapest, superseded, end-of-life model in one format to the most expensive in another?

Link | Posted on May 13, 2015 at 02:04 UTC
On article Hands-on with new Olympus PRO 8mm and 7-14mm lenses (296 comments in total)
In reply to:

alatchin: Every time I read equivalence pop in such as the f 3.5 comment about the fisheye, you should always add "which in turn makes the ff biddy own like a m43s body. Otherwise you are just being misleading with only half the information... The half that makes a ff Ensor like a cure all for less light... Which is only true if you have a large physical aperture, not an equivalent aperture.

Every statement about f-stop equivalency should say something like "this f/1.8 MFT lens is 'equivalent' to a f/3.6 lens of twice the focal length used in 35mm format AT FOUR TIMES THE ISO SPEED", just case people forget to consider _that_ change into noise and IQ comparisons.

Link | Posted on May 13, 2015 at 01:53 UTC
In reply to:

snapa: Now, if they can only update the 3.5 year old sensor, they will really have something worthy of consideration. Changing body material, colors, firmware updates is nice, but... a new improved sensor would be even better, IMHO.

@mosc: why are you obsessed with limiting MFT resolution to what its slowest lens can handle at its slowest f-stop? And when you say "There is plenty of f2.8 m43 glass, it's just very expensive and large", you are thinking only of zoom lenses; there are plenty of MFT _prime_ lenses of f/2.8 or faster that are not particularly expensive and far from large: I love my 60/2.8 macro.

Link | Posted on May 13, 2015 at 01:45 UTC
In reply to:

nikkornikon: They Need to, Like Fuji...to Step away from 16mp. It is time to move on. When 24mp is truly old...16 seems freaking ancient.

@mosc, i agree; I am not really suggesting going to 80MP for the sake of the f/2.8 lenses! I am just saying that many existing MFT lenses can give a resolution/detail advantage from sensors going significantly beyond the current 16MP. I am a fan of the idea of mid-speed f/4 or f/2.8-f/4 zoom lenses, and if the diffraction limit the useful resolution from f/4 is about 40MP (as for the equivalent f/8 in 35mm), then other factors will probably set a limit between 16MP and than 40MP. Frankly, i would use 20MP+ mainly to crop for more telephoto reach than the lenses I prefer to carry.

P. S. Pixel sizes that give too much noise at high ISO speeds do not worry me either: so long as a "high res. low ISO" sensor can give nice highly detailed images at low to moderate ISO speeds, then higher ISO speeds can be handled by trading some of that resolution for noise control by downsampling or other noise reduction strategies, or there can be different models for people with different priorities.

Link | Posted on May 13, 2015 at 01:35 UTC
In reply to:

nikkornikon: They Need to, Like Fuji...to Step away from 16mp. It is time to move on. When 24mp is truly old...16 seems freaking ancient.

@ mosc: if as you say "F2.1 16mp 1/2.33" is not diffraction limited", then with the 4/3" format being over 3x larger, neither is f/6.3 16MP in 4/3", and so nor is f/5 24MP or f/2.8 80MP in 4/3" format -- the MP count for a similar level of diffraction effect goes up as the square of the f-stop and the square of the linear format size.

There is a bunch bunch of MFT lenses (including most MFT primes) offering f/2.8 or faster, and for them 16MP is a very long way from the point where a further increase in pixel count will stop giving further increase in detail due to diffraction effects when used wide open. And when these lenses need to be stopped down beyond f/2.8 for more DOF (the same DOF needs that require higher than f/5.6 in 35mm format), the diffraction limit for equal DOF sets the same MP limit for any format, due to the higher f-stop needed for equal DOF in a larger format.

Give as much resolution as the best lenses can handle, I say.

Link | Posted on May 13, 2015 at 00:11 UTC
In reply to:

nikkornikon: They Need to, Like Fuji...to Step away from 16mp. It is time to move on. When 24mp is truly old...16 seems freaking ancient.

@ 5inchfloppy: people have been saying that 4/3" format is at its limit since the original 5MP E-1 model! Meanwhile there are smaller 1" format sensors at 20MP in some Sony cameras and 18MP in some Nikon One models.

Diffraction is far from being a limy at 16MP for the faster MFT lenses. and why should bodies be limited to what benefits the slowest kit zooms?

Link | Posted on May 12, 2015 at 16:39 UTC
In reply to:

Ace of Sevens: So this is aimed at filmmakers, but has no 24 fps option?

It has all the usual frame rates from 23.98 to 60; the article only mentions 30FPS as the maximum with global shutter.

Link | Posted on Apr 14, 2015 at 20:22 UTC
In reply to:

M Jesper: I'm European, what's a 5lbs? ^.^

@Richard Butler: how about the sensor diagonal in mm? This is also used in the sensor industry, as in "diagonal 11mm" for type 2/3" format; see the Sony product list at http://www.datasheetcatalog.com/sony/44/

This conveys the information that most people want: a single number measure of (linear) sensor size, and in the units used by all but three nations in the world, plus many scientifically literate people in those three nations too.

(Some might complain about the different sensor shapes that can have the same diagonal length, but weirdness like 1/3.2" is no better on that score.)

Link | Posted on Mar 4, 2015 at 22:21 UTC
In reply to:

M Jesper: I'm European, what's a 5lbs? ^.^

@Rickard Hansson That gap from yard to miles is bizarre, but the US has a solution, in the form of two new units of measure often used in the news media: the "school bus" (about 20 meters) and the "football field" (about 100 meters.) I preferred the old-style chains and furlongs.

But its; not just the USA: last time I checked, Liberia and Myanmar were the other two official users of the old British style measures.

Link | Posted on Feb 27, 2015 at 17:50 UTC
In reply to:

Zvonimir Tosic: Interestingly, Pentax representative said that they have already experimented with sensor shift technology to achieve same goal as this, now advertised by Olympus (and Hassy in the past). But, Pentax admits, the result is a large size dataset, plenty of megapickles, but the quality of the picture does not improve.
So instead of delivering that — which obviously is not difficult — they would rather focus how to make native resolution even better.

Which is interesting, as it better sheds light on what Olympus really wants to achieve: a perception that their small cameras (which are indeed limited by sensor size and performance worse that others), are also competitors when it comes to large image sizes.

HowAboutRAW: I was not disagreeing with what you said; my post just happened to appear after yours, but I was commenting on the thread as a whole.

Raist3D: I agree with your defense of Pentax as having made some innovations in the realm of IBIS: for example, using the IBIS motors as an optional moiré avoidance tool, in place of a low pass filter, is cool! But the early IBIS models from those two companies being mentioned mainly reflect that Olympus and Pentax both followed the IBIS lead of Konica-Minolta at about the same time, a years or two after K-M pioneered IBIS, so I would not get to excited about claiming either O or P as the great innovator on the basis of those 2006-2007 models.

Link | Posted on Feb 17, 2015 at 16:16 UTC
Total: 279, showing: 61 – 80
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