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Messages - jrista

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1036
EOS Bodies - For Stills / Re: 7d2 IQ thoughts.
« on: June 12, 2014, 07:30:25 PM »
Here is some interesting research on Quad Pixel tech from a couple of guys at Aptina. Read about it and let me know if you think it might open up the discussion a bit more. The future demands for HDR video and the computational techniques being discussed in this work by Gordon Wan, Xiangli Li, Gennadiy Agranov, Marc Levoy and Mark Horowitz.

https://graphics.stanford.edu/papers/gordon-multibucket-jssc12.pdf

That concept seems really interesting!
I've had thoughts about why no one seem to have adopted something similar to a logarithmic amplifier. That was something I saw in certain radar equipment, where one typically sent out a few kW, and expected to get signal back that were only some fW (10-15W). However, you couldn't be sure on the returning signals strength, so the receivers had to cope with signals that were several magnitudes greater - without frying the entire array of discrete components/transistors/tubes.

In short, that "problem" were solved with stages of amplifiers that, when saturated, automatically opened up for the next stage to take care of the signal handling without ever hitting any ceilings, or frying any components.

In sensors you would've the problem of miniaturising this concept and making some 20 million photon receivers behave identical, but all that counts in the end is counting photons. Every pixel is there for the sole purpose of counting the number of photons that hits it (preferably coming in from the lens). And you don't want to fill your buckets.
Since most of us take our shots in temperatures above 0K, we always have to deal with thermal noise. A logarithmic approach to handling our combinations of signal + noise wouldn't be bad.


Sorry for sidestepping the original idea of this thread.

What your talking about is a photomultiplier. That is actually a very different concept still, and is neither similar to the multi-bucket pixels nor DPAF. :P

Photomultipliers do use mult-stage amplifiers to significantly amplify extremely low signals by a significant magnitude, without requiring ultra-specialized amplifiers that can do so without frying themselves. But that's just a more complicated means of amplifying a weak signal. It doesn't actually improve the signal strength itself, so it can neither reduce noise, nor support something like HDR.

The multi-bucket pixel concept in that paper effectively embeds analog memory into the pixel. Global shutter sensors already do this, but they only have a single memory (when the exposure is done, every pixel's charge is immediately pushed to it's memory at once, the pixels are reset, then the memory can be read out in the background while the next exposure occurs.) Multi-bucket memory allows charge to be pushed to memory more than once, which expands the dynamic range by N times. At the point of read, the charge stored in each bucket is then binned as the pixels are read out.

That is significantly different than a photomultiplier, as instead of amplifying the signal (which also amplifies the noise, and does not actually improve the quality of the signal itself), it allows longer exposures combined with multiple "memory pushes" to literally enhance the quality of the signal itself WITHOUT amplification. THAT....that is what is so intriguing about the multibucket concept. ;)

1037
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 12, 2014, 07:20:11 PM »
As a matter of interest, would an expectation of relatively clean image quality at ISO 1600 be unrealistic for a crop body?
One man's clean is another man's filthy. It's best to speak in comparative terms. For me, if the 7D-II's ISO 3200 image looks as good as the 6D's ISO 6400 image then I'd be very happy with it.
I hear you on that.

As a birder, I dial in ISO 400 on my 500D but just like the 7D, anything over 400 leads to very obvious noise.
Anything over ISO 800, the images become somewhat and probably poorly described as rough.
Useable ISO 3200 would be a very worthwhile reason to buy this camera.

It's not going to happen, though. I agree, the most usable ISO stops somewhere around ISO 800 to ISO 1600 (depends on the specific copy, and to some degree temperature). The 7D has 41% Q.E. already. To DOUBLE sensitivity (or reduce noise by 50%), the 7D II would need 82% Q.E. Sony recently released the ICX694 CCD sensors for astrophotography. Those are cooled CCDs, about -35 to -40 degrees C delta T, and those get "only" get 77% Q.E. (which, BTW, is actually VERY high...the prior generation usually got somewhere between 45% - 59% Q.E. most of the time, with the exception of a couple high end ones without anti-blooming circuits that get 90%.) On top of that, they have the lowest read noise of any of the available astro CCDs on the market at the moment, at 0.003e-/px/s (the prior generation of CCD sensors had around 0.02e-/px/s, an order of magnitude MORE). DSLR sensors, at room temperature, has more on the order of 0.5e-/ps/s, another order of magnitude more.

There is just no way Canon is going to achieve 82% Q.E. in any respect (not unless they have some seriously amazing patents they are hiding away somewhere), and there is little chance they will be reducing dark current noise by any significant degree. That means that the 7D II won't have anywhere near a factor of two improvement in high ISO noise. That means it won't even be that much more usable at ISO 1600, let alone ISO 3200.

If you really NEED usable high ISO, you need to move to a larger sensor. Total light gathering capacity is ultimately what matters for high ISO...and FF sensors simply have more, always will have more.

1038
Animal Kingdom / Re: Lizards
« on: June 12, 2014, 01:46:38 AM »
Here one from last year - lizard is being fed a live grub.

Jpeg with ISO 10000, EF100 f2.8, 1/1000, 5D3.

Wow. ISO 10000 f/2.8? That must have been ONE DARK scene...!

1039
Animal Kingdom / Re: A new take on BIF
« on: June 12, 2014, 12:33:11 AM »
Congrats on getting the shot. Couldn't have been easy. I've seen Bat in Flight shots in video before, but usually they are well lit with artificial lighting.

1040
Animal Kingdom / Re: Your best animal shots!
« on: June 12, 2014, 12:29:07 AM »
Sad Eyes

Yellow Eyed Penquin

Kaikoura Seal

Capuchin

Tuatara


WOW. These are STUNNING. Absolutely love the color, and the subjects and composition are excellent.

1041
Animal Kingdom / Re: Show your Bird Portraits
« on: June 12, 2014, 12:26:55 AM »
Juvenile Northern Rough-winged Swallow, catching its breath.  I was pretty astonished by this bird, I was standing at an overlook above a small lake when the bird landed just a few feet away from me on the fence railing.  It was plainly very out of breath and it sat there for a couple of minutes while it got its breathing under control.  My guess is that it is newly fledged and that it is just learning the ropes of being a swallow.

Canon 5Diii, 400DO, ISO 320, f6.3 @ 1/800, aperture preferred setting.

Great shot! Poor little guy, he does look beat. Wonderful detail, though.

1042
Animal Kingdom / Re: Lizards
« on: June 12, 2014, 12:26:22 AM »
Wonderful shots, guys! Really amazing detail. Lizards are intriguing subjects, what with their scaly and colorful skin. Looking forward to more!

1043
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 12, 2014, 12:18:34 AM »
I rarely switch modes in the middle of a shoot. I pick one for the scene, and keep it there for most of the shoot. I have accidentally moved the mode selection on my older bodies. I'd welcome this EOS-1 set-up.

Besides, is it easier to take your eye out of the viewfinder to switch modes than it is to hit the button and spin the dial while still keeping your subject in the viewfinder? We all shoot different. I think it would take a day to get used to, and you might not want to go back.

The mode dial thing really comes into play with custom user modes. With bird photography, you often have to switch modes quickly, when say an Egret or Heron goes from happily hunting fish to flying off in a start because someone decided to stomp up to the edge of the pond and oogle all the birds that WHERE there a moment before with their woefully inadequate binos, then you need to switch to a mode tuned for flight photography in a heartbeat.

With the 7D, I was able to do that just by tightly pressing my index finger to the mode file and rolling. I pretty much always had my eye away from the VF for that, but it was still on the bird, sighting in so I could get the flight shots. The 7D was always a pain for flight, at least with the 600, so I rarely ever got any good shots. The large frame of the 5D III is excellent, however now with the mode dial lock, I have to take my eye off the bird to enter the custom mode. I'm now working on configuring my alternative AF mode so I can reconfigure that one button to an AF setup better suited for BIF, and I think that will do the trick (and possibly even be better than my 7D was.)

Anyway...there ARE reasons to quickly change camera modes. More configurability, and the option of toggling subsets of the camera system into different modes, would actually make for a more flexible setup. I like where Canon has started going with the 5D III...it'll be very interesting to see how much configurability the 7D II has.

1044
Photography Technique / Re: technique for hand held larger lens
« on: June 12, 2014, 12:07:57 AM »
Check out the third photo on this page (of Arthur Morris) - that's how I hold my lenses, if they have feet. 

Me, too, except I try not to stick my tongue out like that.   :P

Ah! But you see, the tongue is part of the whole Morris Special Technique. It acts like a wind sensor, giving you early cues as to direction and strength, allowing you to preemptively combat wind pressure. Besides, it makes you look like a goofball, so the birds won't be afraid. :D You GOTTA stick the tongue out! :P

1045
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 12, 2014, 12:00:32 AM »
I think touch screens will have a lofty place among entry level cameras and mirrorless cameras. When it comes to professional grade cameras...I don't really think that touch screens are going to be all that important.

Think about what you are saying.

Can you set a 600 RT without ever taking your eye off the viewfinder? Select flash groups? Adjust flash A:B C balance while looking through the viewfinder?

And, with that new 5DIII can you set tracking sensitivity or accelerate or decelerate your tracking through the viewfinder?

Setting tracking with a touch screen -- now that alone would be worth it.

First, I never said touch screens weren't useful. Just that they won't be the most important feature of an action-oriented camera like the 7D II.

Regarding flash...no, however I have never really needed flash for my bird and wildlife photography. I don't think flash is used all that much with sports either. Flash also quickly becomes useless in high frame rate photography, since even with high end Eneloop fast cycle batteries, the flash still can't keep up.

So whether you can control flash or not is moot. It's unimportant in the high speed action photography context.

As for AF, the 5D III brings AMAZING button customizability. It actually allows you to configure the "AF Stop" button to alternative behaviors, one of which is "Switch to registered AF function". You can register your own AF function, and switch between it and the main AF function, with the press of a button. So, while you don't have 100% complete control over every aspect of the AF system from individual buttons, you can do what you stated, change tracking sensitivity, acceleration, etc. without moving your eye from the VF.

I suspect that functionality will only get more refined in future generations of Canon pro-level DSLRs. And regardless...even if you can tweak those settings on a touch screen, you still have to take your eye away from the VF, which is worse than what I can do now with my 5D III.

Yikes! You're starting to sound like Sella or Dilbert. You don't use flash so there's no reason for Canon to make it easier for others?

*Sigh* Very low blow, man. And uncalled for. And I repeat myself:

Quote
First, I never said touch screens weren't useful. Just that they won't be the most important feature of an action-oriented camera like the 7D II.

^-- That is not something Dilbert would say. He refuses to acknowledge any point other than his own. I have acknowledge your point. I NEVER said touch screens weren't useful. Nor did I say they shouldn't add one to the 7D II. I only said that it won't be the most important feature of an ACTION-ORIENTED camera like the 7D II. My prior reply to Don explained why I believe that. Do you read?  ::)

And, of course, you can customize your autofocus settings and add them as a custom functions. But in order to do that, you still have to go through the old-fashioned menu and dial and button setting procedures. It's just so much easier and more intuitive to change and adjust any setting with a touch and swipe system than a scroll and press system. You can still set a custom function, but you can do it much more quickly and intuitively with a touch and swipe.

Your still completely ignoring what I've said, assuming you even read it. What your talking about has nothing to do with what I was talking about. AT ALL. WHATSOEVER.

I was simply comparing the usefulness of a touch screen as a primary mode of camera operation, based on what Don originally said. I HAVE NEVER ONCE made ANY argument that Canon SHOULD NOT add a touch screen to the 7D II. That IS NOT MY POINT. I'm sure it will probably have one, but that is entirely irrelevant to the point I was trying to make. You've inferred something from my posts that is not there.

And once again, why would anyone think that adding a touch system is somehow going to mean taking away buttons or wheels? It augments, does not replace, the existing system.

Again, that is not my argument, I never said Canon shouldn't add a touch screen. ??? Go re-read what I wrote, maybe a few times, and once you understand it, then we can have a discussion.  ??? ??? ???

1046
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 11, 2014, 11:04:24 PM »
I think touch screens will have a lofty place among entry level cameras and mirrorless cameras. When it comes to professional grade cameras...I don't really think that touch screens are going to be all that important.

Think about what you are saying.

Can you set a 600 RT without ever taking your eye off the viewfinder? Select flash groups? Adjust flash A:B C balance while looking through the viewfinder?

And, with that new 5DIII can you set tracking sensitivity or accelerate or decelerate your tracking through the viewfinder?

Setting tracking with a touch screen -- now that alone would be worth it.

First, I never said touch screens weren't useful. Just that they won't be the most important feature of an action-oriented camera like the 7D II.

Regarding flash...no, however I have never really needed flash for my bird and wildlife photography. I don't think flash is used all that much with sports either. Flash also quickly becomes useless in high frame rate photography, since even with high end Eneloop fast cycle batteries, the flash still can't keep up.

So whether you can control flash or not is moot. It's unimportant in the high speed action photography context.

As for AF, the 5D III brings AMAZING button customizability. It actually allows you to configure the "AF Stop" button to alternative behaviors, one of which is "Switch to registered AF function". You can register your own AF function, and switch between it and the main AF function, with the press of a button. So, while you don't have 100% complete control over every aspect of the AF system from individual buttons, you can do what you stated, change tracking sensitivity, acceleration, etc. without moving your eye from the VF.

I suspect that functionality will only get more refined in future generations of Canon pro-level DSLRs. And regardless...even if you can tweak those settings on a touch screen, you still have to take your eye away from the VF, which is worse than what I can do now with my 5D III.

1047
...
The D800/E are the best still cameras as far as dynamic range goes. That makes the difference 2.27 stops at best, or 2 1/4 stops.
...
The D600/610 are a little better than the D800/E in terms of screen DR.

Indeed, you are right.

1048
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 11, 2014, 09:38:30 PM »
Yes.... the touch screen is a game changer... either use it like a 1DX or tap the screen.... as touchscreens mature it will be interesting to see what happens.

Maybe, it depends. Personally, I'm the kind of shooter that doesn't like to take the camera away from my eye if I can avoid it. You can easily miss the best action that way. (I just did recently, testing my new 5D III...snowy egret fluffed up as I was fiddling with something on the camera...when I had my eye AWAY from the VF!! BAH!) I like a camera that has LOTS of buttons that allow me to directly access LOTS of things, combined with a viewfinder that displays enough information to allow me to configure everything about the camera, mode, exposure, AF, metering, etc. all from my near-permanent viewpoint through the viewfinder.

Button layout plays a BIG role here, as does the number of buttons and how configurable each one is. This is one of the areas I think Canon EXCELS at, and one of the few primary reasons I've stuck with the brand. Canon ergonomics are superb.

Touch screens...well, they are very intriguing, and certainly make using P&S style cameras, like say the EOS M, easier and more convenient. But, they really don't do squat to help me configure my camera on the fly without ever removing my eye from the viewfinder. By definition, touch screens require that I remove my eye from the VF and touch the LCD screen on the back. Not only that, I have to take my eye off the subject to use a touch screen. Not very good for action shooters, who have to keep their eyes on the scene/subject at all times and be ready, at all times, to press the shutter button when the action occurs.

Buttons and a good VF HUD are essential for what I do. For the most common things, I barely even have to think...changing exposure, selecting AF points, etc. are largely autonomic, procedural memory and a tiny fraction of my mind take care of them when I need to (most of the time). I have to think a bit more to do other things, say lock autoexposure (if I'm using an auto mode), because I don't do it as often, but I can still do it without taking my eye away from the VF with lots and lots of buttons. I would actually prefer to have buttons rather than a dial for mode selection...the dial is actually difficult to use, even more so these days, like with the 5D III which has the mode dial lock button...it's basically a two-hand requirement to change modes now. (I like that in one sense...now I'm not changing modes accidentally, which occurred far too often with the 7D...but now I can't simply roll my left finger along the dial to change modes...)

Anyway...I think touch screens will have a lofty place among entry level cameras and mirrorless cameras. When it comes to professional grade cameras...I don't really think that touch screens are going to be all that important. They introduce a highly disruptive workflow for changing camera settings, one that is not conducive to action shooting at all (and, since this is the 7D II were talking about...action is basically what it's designed for.)

1049
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 11, 2014, 09:25:26 PM »
Can somebody explain to me HOW lack of a mode dial is a good thing? I've never really understood the button system on the 1D line. To me it seems to be a lot slower to switch modes like this.

Dials are difficult to seal. You can't REALLY seal a rotating component...there is always going to be the open joint where the seal meets the shaft of the dial.

Buttons, on the other hand, can be completely sealed. You place the button on the outside of the seal, the electronics that activate on "press" inside the seal, and everything is good.

The 1D X uses buttons to meet it's weather sealing grade...which is quite a bit higher than the current 7D. If weather sealing is important (and if you shoot sports or any other kind of action, it's plenty common to shoot in the rain or other wet weather), then the 7D II moving to a button-only system is actually a rather welcome thing.

1050
Animal Kingdom / Re: Show your Bird Portraits
« on: June 11, 2014, 05:44:46 PM »
Here's one of a juvenile Bald Eagle in Alaska last summer.  Still don't have a 5D, but it was great to use the GPS function on my 6D to plot every shot I took up and down the Inside Passage.  This one was taken at the Anan Bear Observatory.

That's a big bird! Interesting pose, too...you can kind of see the birds inexperience.

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