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Messages - jrista

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1321
Animal Kingdom / Re: Show your Bird Portraits
« on: December 27, 2013, 10:03:50 PM »
Scarlet Macaw, Disney's Animal Kingdom
(6D, 24-105 @ 1/125, f8, ISO800,105,  about 1:1 crop)

Beautiful. Love that detail! Reds are a bit bright...might try using some selective color editing to pull them down a bit, without otherwise adversely affecting the rest of the image.

1322
EOS Bodies - For Stills / Re: The Unthinkable: Swapped out 5D3 for 6D
« on: December 27, 2013, 10:02:52 PM »

It really depends on the number of pixels in the area of the frame filled. The pros I follow generally fill the frame exactly right, regardless of the sensor used.

And what constitutes filling the frame "exactly right"?  You mean filling the frame with 90% bird?

It isn't so much a matter of percent. It is a matter of composition. Pros have the skill to utilize at least 90% of their frame, it not even 100%, for the composition they want. That does not necessarily mean the bird itself will be 90% of the frame. That doesn't really matter in the end. What matters in the end is that you utilize the majority of the pixels on the sensor. Then, pretty much regardless of output size, your image will have less noise/more DR.

Sometimes "filling the frame" means the bird fills 40%, and some negative space and maybe a counter object or two are included. You usually leave a little bit of space for cropping/straitening, but that isn't usually significant. Other times, "filling the frame" might mean the just bird's head is 80% of the frame, with the appropriate amount of negative space around it for appealing composition. Either way, there is little cropping, so your maximizing the potential of the sensor, minimizing noise, etc.

As for the full frame vs. crop sensor comparison of DOF, that's not really what I was discussing, as I know the DOF is shallower with a full frame.  I just meant that if you filled the frame with the bird, the DOF is still pretty shallow at 600mm, even with a crop camera.

Yeah, generally true.

As for not understanding what I meant, I'll try to clarify (though I'm sure you'll find a way to say I'm wrong).  As a bird becomes larger in the FOV, the accuracy of the focus needs to be that much finer, mostly due to the shallower plane of focus relative to the size of the FOV (besides the larger number of pixels that are defining what is sharp detail and what is out of focus).  If there is a pronounced focus inaccuracy when the bird is small in the field of view, yes that's more annoying and really unusable autofocus.  But correcting it to an adequate degree is easier to do, than to correct an autofocus issue that is effectively millimeters deep in the plane of focus...as I assume the problem you're describing is.

The increase in subject size in the frame is often offset by increased detail, which provides a greater potential that the AF unit will find the necessary contrast to operate well. The bigger issue with wide swings in subject distance is AFMA...bummer of it is, AFMA really works for the focal length you tune it at. Much closer or much farther, and the AFMA setting is not going to be ideal. Puts a lot of pressure to make sure you AFMA at the most ideal "happy medium" point somewhere between your average far distance and average near distance...but it will never be perfect for all photos. So, even if you do manage to maintain good focus with a nice contrasty area of the bird, doesn't necessarily mean it will be sharp as a brand new razor.

1323
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 27, 2013, 09:52:42 PM »
Oh, by the way... if you have found this "official press release" and they did say that the "7D II will receive a new sensor" technically the sensor from the 70D put into the 7D II is a "new" sensor compared to the original 7D. You can't argue with them if they put in the dual pixel 70D sensor into the 7D, "oh but you said that the 7D II will receive a new sensor" they will say that is a new sensor.

No, no, no - Canon will not be quite SOOO cheap. Almost, but not quite. ;D

Even with my rather low expectation regarding Canon's innovative zest :-) - I do expect the 7D II (whatever it may be called) .. to be announced in 2014 to NOT have the 70D sensor .. but something "slightly improved" ... say 24 MP and 0.1 EV better DR ... and of course Dualpixel-AF and other "video Optimization" on board.  ;D

I am rather sure ... because otherwise even Canon could not possibly charge USD/€ 2500 for the 7D II (whatever its goin to be called) ... lol

Really? After 4 years... in terms of MP... the difference between 5D Mark II and the 5D Mark III is 1MP.
Even if you take into consideration, the 50D to 60D to 70D, the increments are relatively small max 2-3MP.
The Biggest surprise of them all was the 1Dx... it was an increase from the 1D, but a decrease from the 1Ds.

You're telling me that the 7D Mark II will have a whole 6MP difference between Mark I & II?
May be if they changed the name, but that won't make it a 7D mark II... its a different gear altogether.

€ 2500 for an APS-C??? Why??? Have you seen the prices of the 6D and even the 5D mark III, lately?

18 or 20 megapixels is now ancient history..... Just like when 10 was normal and then we all made the big jump to high megapixel cameras with 18 meg sensors, we will soon arrive at a time where 25 meg is the new 18

I don't think Canon got that memo when they released the 1Dx, SL1, EOS M, EOS M2, t5i, even the 6D and 70D has only 20.2.

I'm not complaining, 18MP is all I need.

Canon got the memo people were sending with the 1D X, 5D III and 6D: Fewer megapixels, better high ISO. That WAS the outcry before the D800. I asked for it (along with higher frame rate, which the 1D X delivers in spades.)

However, SINCE the D800, the memo being sent from Canon fans is different. They already got their low megapixel camera that kicks ass at high ISO. Now, they want something different. They want high MP...as many megapixels as they can get their hands on. And more dynamic range. Different messages, different times. Canon delivered, exquisitely, EXACTLY what their customers asked for with the last round of major upgrades. The low-end entry lebel rebels and whatnot don't matter...no one really gives a damn about them, they are unimportant in the grand scheme of things. The 70D is barely important, even, more of a stopgap to fill in the time till the 7D II release than anything, and a tool to showcase the fact that Canon is still innovating in the sensor realm. Consumers will buy the entry level and midrange camera models pretty much regardless, so their stats aren't nearly as important. The camera models that matter are the xD series models. The high end models. The models that have a FOUR YEAR cycle, rather than a one year cycle.

It is still early, rather quite early, for Canon to be releasing replacements for the 1D X, 5D III, and 6D. The 7D was released a bit after the 5D II, so it is no surprise it's coming would be later...however if Canon was indeed caught off guard with the onslaught of high megapixel parts from SoNikon, it is no surprise they require additional time to respond to the new demand, the demand for higher megapixels. The 7D II won't just be some mediocre half-assed upgrade. The 7D is a professional-grade part, Canon knows it's a popular line, Canon knows that simply "using the same old sensor" is just an insult to their customers, and Canon knows that to compete, they have to COMPETE. The chances are low that Canon won't do something very compelling with the 7D II. I also think the chances are relatively low that they will eliminate the 7D line...it's been wildly popular and an exceptionally good seller...seems highly doubtful Canon would do away with such a success.


1324
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 26, 2013, 07:11:03 PM »
What do you mean, you have to process them all?

This raises an interesting question..... Can you batch process images in Lightroom?

Answered my own question..... Yes, you can batch process images in Lightroom..... Kind of shoots the "increased workload with higher frame rates" argument in the foot....

Please see my previous answer. It isn't the actual processing. You can batch that, but at least in my case, after batch applying initial edits, each of my picks inevitably needs additional processing. Batch just reduces that part of the workload. The part of post processing that I am referring to, however, is not the editing, its the culling, organizing, etc.

1325
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 26, 2013, 07:09:25 PM »

I don't want anything more along the lines of "all cameras being video cams and stills being just single frames extracted from the video stream". No, no, no.


You're getting it wrong...
I'm sure, when you use your 7D it isn't always shooting 7-8fps...
If you have 24fps or higher... you just have more chances to capture the perfect moment.
E.g. when a lion pounces on a wilder beast or when a eagle grabs a trout from a river, when Beckam bends it.

People that own a 14fps 1DX.... do you wish for higher?
If so why?
If not, why is 14fps perfect or why not settle for less?

There is a point where you end up with too many frames. At 8fps, I get a LOT of frames. It is a lot of work to wade through them all in post. I imagine 12fps is even more heavy duty work to pick out the good ones and weed out the bad ones in post. Then you have to process them all, and while you can do some of that in bulk, you still have to fine tune each photo. At 24fps or higher, you would just have WAY too many frames to deal with. Not only is that going to use an immensely greater volume of disk space, but it would begin to exponentially increase your workload in post. I can't even imagine what 30 or 60 frames per second would be like...one fraction of a second would get you a dozen frames, a SHORT few-seconds would get you hundreds of frames. It's impractical to have that many frames to deal with in post.

That's why, with a 1D X, you have the handy option of configuring a "slow" burst rate that is lower than 12fps, because you don't necessarily always want so many frames for all kinds of action. Some action benefits from a larger separation between frames, rather than less, and fewer frames is easier to deal with in post. Unlimited frames is not really a good thing, it needlessly increases your workload with rapidly diminishing returns when you get around 20fps and higher.

What do you mean, you have to process them all?

See my reply to Don's last message.

If the 1D X has the option of slowing burst rate from 12fps, you think they won't slow it down from 24fps?
Even Magic Lantern allows you to increase and slow down fps... and thats in video mode... I can shoot from 1 or 2fps to all the way to 35fps at 1080p using FPS override.

I am saying that 24fps is beyond the level where most photographers would want to deal with the output. At 20fps and beyond, it's just too much data. There are plenty of times when I think I get too many shots with my 7D...I've spend a considerable amount of effort trying to hone my skill with the shutter button, in an attempt to reduce as much as possible the excess...at this point, I generally get 3-5 frames a burst, and I am generally able to get just the action sequences I want.

@Jrista specifically... you currently have the 7D, and you use the 600mm f/4 on it.
I'm sure the 600mm cost you a pretty penny. I've checked out your pictures (on your site), I'm sure you're happy with them, right?

I am satisfied with some of them. I'm a perfectonist, and in my opinion, I still have a long road ahead of me...

Why not upgrade to FF, instead of wasting your time with APS-C?
And, use extenders to give you that extra reach?

I fully intend to. Buying a $13,000 lens tends to drain you of excess funds for a while. ;)


@ Everyone else... Lets be real, look at canon history.... 7D to t2i to 60D to t3i to t4i to t5i... all had the same sensor.
70D comes out, new sensor.... what do you really think is going to be in 7D mark ii? A newer sensor from the 70D? Not a friggin chance....

Even if they took away the video mode, its still going to have 70D sensor in it... canon history shows that....
You're just wasting your breath complaining... if you're happy with the current 7D, stick with it.

You are conveniently ignoring what Canon themselves have explicitly said about the 7D II. It WILL get a new sensor, and possibly even a new name to go along with whatever "special" think they intend to do with it.

1326
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 26, 2013, 07:03:30 PM »
What do you mean, you have to process them all?

This raises an interesting question..... Can you batch process images in Lightroom?

You guys aren't quite understanding. You have to process them all...not necessarily manually tweak each and every image. You have to go through them all and pick keepers and rejects. Not every frame will be ideal. You have to FIND the ideal frames. You have to look at them at full size to identify which ones are ideal. Some frames may appeal ideal as a thumbnail, but end up obviously blurry when viewed at full size. There is no quick way to identify picks and rejects. THAT is a VERY time consuming process, and gets more and more time consuming as RAW image sizes get larger. Having 1-2 second bursts that result in 40-60 frames is insane. Not only would you need terrabyte sized memory cards, you would need tens of terrabytes of disk space to store everything, unless you don't keep the majority of your shots (personally, I keep as much as I can, and only literally delete obvious rejects...plainly out of focus, wildly motion blurred, etc.)

At 60fps, a 2 second burst is 120 frames. That's just a ludicrous amount of data, no matter how you look at it. I would be very happy with 10fps...8fps is sometimes just slightly too short on occasion, and a slightly higher frame rate would fix that. But I wouldn't ever want 20 or more...just far too much data to deal with, requiring a much greater expenditure in storage space across the board. Impractical.

Also, don't forget...keywording, metadata, and any other form of organization of your images. I tend to tune the keywords for and explicitly add metadata to each of the images I do not reject to improve searchability.

1327
EOS Bodies - For Stills / Re: The Unthinkable: Swapped out 5D3 for 6D
« on: December 26, 2013, 06:55:41 PM »
I had thought you already bought a 5D3 and were using it with your 600 ii.  Would drive me nuts I think!

I have used "a" 5D III with my 600 II, but I have not yet purchased a 5D III of my own yet. I can only absorb so much outflow in a year, and the lens sucked me dry. So...5D III is on hold until I have more cash flow and savings.

The slight jitter that causes those misses is also present in the 7D's 19pt AF system...it just doesn't sit still between shots...even if the subject is already locked, there is pretty much ALWAYS movement, ever so slight, between every frame.

Of what mode are you talking about - servo af or one-shot with continuous fps?

What I experience on both the 6d and 60d with a thinner dof like on the 100L is that when you re-af at the same point w/o camera movement, the lens will often choose a slightly different focus... and lensrentals says it's even better to af somewhere completely else first as this gives more exact results than slight af corrections.

Either, in the case of the 7D, but it is more pronounced with Servo. This isn't a DOF problem. It happens with all my lenses, wide open or stopped down considerably. I had the problem with my 600/4II when stopped down to f/8 just the other day. For such a long lens like that, DOF is pretty small when you get close enough to a bird to be "frame filling", and even at f/8, the jitter can still result in slight softening of detail that isn't exactly at the plane of focus. I like the 7D, but the AF jitter is the single largest IQ drawback of the camera.

All of my lens are properly AFMAed as well. I've used manual techniques as well as FoCal to calibrate each of my lenses. Even shifting AFMA about 2-3 notches results in a visible change with the 600mm lens, so when the lens is that sharp, slight changes in the focal plane can mean visible changes elsewhere, unless you are downsampling by 2x or more. (When downsampling, it is never really a problem, but I generally print 24x36 and larger, so it really matters.)

For filling the frame with a bird at 600mm on the 7D, I could definitely see how even slightly closed to f/8, the plane of focus is extremely shallow, and thus your autofocus will vary on what it focuses on, and with the accuracy of that focus.  You're usually trying to get the eye of the bird in sharpest focus, I assume?  Plumage is important too, but less so than the eye, isn't it?

An APS-C at f/8 will have a deeper DOF than FF at f/8, for an identically framed subject. So in that sense, APS-C is actually better for DOF. The problem is most definitely not the depth of field, though...the 7D AF system has an uncontrolled jitter, such that it always adjusts every inter-frame period, even if it does not need to. For a stationary subject at a good distance with plenty of DOF, the actual plane of focus WILL shift around your intended focus point if you simply hold the AF button down and let it do it's thing. After a while, it will settle, so long as you do not take a picture. When you are doing AI servo and tracking a subject or taking multiple frames in sequence, ever frame the camera will perform AF, and even if the subject has not moved, the plane of focus will change...ever so slightly, but often just enough to be noticeable and sometimes enough to kill that frame.


However, if you're not filling the frame with a bird...like say especially if the bird is 1/4 the width of the frame or smaller, then in my opinion most of any focus problem, however minute, is easier to deal with and identify the cause.  I guess that's obvious.

Hmm, not sure I understand... The smaller the bird is in the frame, the more pronounced any issue is, including missfocus...the fewer pixels you have on subject, the more magnified things like missfocus, camera shake, optical aberrations, etc. will be, relative to the subject.

In my opinion you can get pro quality images of birds by only filling the frame where the bird is a max of 1/3 the width (or height) of the image, but admittedly I'm not the birding expert.  I've seen plenty of great images that were cropped about this much, though.

It really depends on the number of pixels in the area of the frame filled. The pros I follow generally fill the frame exactly right, regardless of the sensor used.

1328
EOS Bodies / Re: Canon Dual-Scale Column-Parallel ADC Patent
« on: December 26, 2013, 06:41:50 PM »
The patent is old and probably conceptually invalid due to prior-art. And I'm pretty surprised about the confusion about what it does, as it's fairly straight-forward and easy to read.

What Canon patented here is a specific implementation, not a method, of a two-stage pre-selection of AD reference voltage.

As the signal is presented to the AD section, the absolute voltage is first presented to a comparator circuit. In the "determination period" the comparator sets the AD ramp signal to either a high (fast) reference ramp, or a low (slow) reference ramp.

If the signal is (was) lower than the comparator set point, then the AD works with a slower ramp and after that it scales the result down numerically by a factor of [high ramp] / [low ramp]. This enables a "slower" readout of weak signals, something which offsets the crappy (noisy) AD converters base level noise for low-level signals. Signals stronger than the comparator set point will be digitized with lower precision, but in strong signals that inaccuracy is totally dominated by photon shot noise.

If you use higher quality AD converters or a slower bitrate conversion this two stage setup is not necessary. Often slower reads are implemented by higher parallelism, using more AD converters per image. This is what Sony's Exmor, or indeed any other of the five big one's on-sensor AD conversions. They use the "slow ramp" for all pixels, all the time, anyway.

Thanks for the explanation! Basically what it sounded like, but I couldn't figure out the exact mechanism by which they reduced noise. Slower readout for lower signals makes total sense. Sorry, I was reading a rather poor translation from japanese...god awful ass-backwards sentences and funky wording.

1329
Animal Kingdom / Re: Show your Bird Portraits
« on: December 26, 2013, 06:38:47 PM »
Canon 7D 400mm L f5.6

That is rather phenomenal. You must have been pretty close, to get that perspective that clearly.

1330
Animal Kingdom / Re: Show your Bird Portraits
« on: December 26, 2013, 06:37:59 PM »
Killdeer



Beautiful. Love the contrast. The shading is interesting, too.

1331
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 26, 2013, 11:23:44 AM »

I don't want anything more along the lines of "all cameras being video cams and stills being just single frames extracted from the video stream". No, no, no.


You're getting it wrong...
I'm sure, when you use your 7D it isn't always shooting 7-8fps...
If you have 24fps or higher... you just have more chances to capture the perfect moment.
E.g. when a lion pounces on a wilder beast or when a eagle grabs a trout from a river, when Beckam bends it.

People that own a 14fps 1DX.... do you wish for higher?
If so why?
If not, why is 14fps perfect or why not settle for less?

There is a point where you end up with too many frames. At 8fps, I get a LOT of frames. It is a lot of work to wade through them all in post. I imagine 12fps is even more heavy duty work to pick out the good ones and weed out the bad ones in post. Then you have to process them all, and while you can do some of that in bulk, you still have to fine tune each photo. At 24fps or higher, you would just have WAY too many frames to deal with. Not only is that going to use an immensely greater volume of disk space, but it would begin to exponentially increase your workload in post. I can't even imagine what 30 or 60 frames per second would be like...one fraction of a second would get you a dozen frames, a SHORT few-seconds would get you hundreds of frames. It's impractical to have that many frames to deal with in post.

That's why, with a 1D X, you have the handy option of configuring a "slow" burst rate that is lower than 12fps, because you don't necessarily always want so many frames for all kinds of action. Some action benefits from a larger separation between frames, rather than less, and fewer frames is easier to deal with in post. Unlimited frames is not really a good thing, it needlessly increases your workload with rapidly diminishing returns when you get around 20fps and higher.

1332
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 25, 2013, 01:22:47 PM »
exposure time should remain completely under (stills) phtotographer's discrete control.

Oh, it would be, under what I was describing.  You'd set your exposure time, and then in post, you could control which adjacent subframes get merged in and which ones don't (including using just the single subframe).  When viewed in-camera, it could either make an educated guess or show you just the single subframe, depending on user preference.

That means the results are entirely arbitrary. You aren't doing exposure at all, your simply ripping out a bunch of  frames agnostic if an explicit exposure time. I think that is even conceptually more difficult for most photographers to grasp (not to mention MASSIVELY wasteful of space). Again, it could theoretically allow you to have infinite DR, but it would make photography very difficult, rather than very easy (and it's never been easier than it is today.)

Exposure control needs to be under photographer control. You can't arbitrarily take a photograph and then decide exposure in post...you could massively underexpose if a majority of the frames ended up "unusable" once you got it all onto a computer. This isn't an argument about an option for improving sensor sensitivity or dynamic range, it is a discussion about redesigning the entire way we do photography, which I think is out of context.

I don't see why setting exposure time with single shot HDR is such a hard thing to grasp. If the camera just tells you the longest exposure of the group, and you already set how many shots per group and the difference in exposure per shot, everything is a known quantity.
All we need is an "HDR" slot on the mode dial.

We weren't originally talking about HDR. We were talking about sensor performance, and how to improve it (at a fundamental technical level, abstract of any actual specific use case.)

1333
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 25, 2013, 04:43:35 AM »
As a side note, since it would take an increase to 82% Q.E. for the 7D II to gain a true ONE stop improvement in high ISO performance, we can never hope to see a true two stop improvement. The 7D II, nor any successor, nor any new pro-grade APS-C line of cameras from Canon or anyone else, will ever perform as well as a FF sensor that has larger pixels. So long as the average pixel size for FF sensors remains larger than the average pixel size for APS-C sensors, FF sensors will always perform better at high ISO. Nothing we can do about that...its just physics.

Well, there are a few tricks that Canon could do.  For example, if a camera used a series of fast exposures, the camera could do motion vector analysis on various parts of the image, then add them programmatically after compensating for camera and subject motion, resulting in roughly the same image as you'd get with the shorter shot length (blur-wise), but with the SNR of the longer shot length.  However, that's way beyond the realm of sensor tech.  :)

How would that work with a selectable shutter speed, though? I mean, if I as the photographer chose a 1/1250s shutter speed, a single exposure that long is going to be better than multiple separate exposures blended together. You'll lose light in the interframe time as well, so gain would have to be higher...

You're assuming a mechanical shutter.  Consider a vertically stacked sensor that can push its value down to a buffer deeper in the silicon or, for simplicity, an interline transfer design.  You can then sample the image with no rolling shutter (bette for video) and no delay between shots.  If a mechanical shutter is desirable for some reason, open it before the first frame and close it at the end.

It matters not whether the shutter is mechanical or electronic. What matters is that the PHOTOGRAPHER selects the EXPOSURE TIME (shutter speed). Shutter speed is shutter speed, regardless of whether the shutter is mechanical or electronic. If the photographer chooses a 1/2000th shutter speed, then that is AS LONG AS the camera can expose. Trying to make a better exposure by taking several short exposures within that 1/2000th window is likely impossible. At the very least, there is going to be some lag time for read or "ship the charge off to a buffer" between each partial exposure. That lag time is going to cost you light. Because shutter speed is a user selectable quantity of time, gathering light for that total time is the best we can do.

Other way around.  The user typically chooses an exposure time with the primary goal of avoiding blur from camera or subject motion.  If the user allows the camera to do so, however, the camera could use a much longer exposure than what the user selected, dicing that long exposure up into pieces of the user-specified length, and compensating for motion to approximate an exposure of the user-chosen duration while gaining increased accuracy in portions of the image that did not change significantly or exhibited only trivial transformation, such as shifting one way or the other, similar to the way MPEG compression reduces data rate by describing portions of one frame in terms of adjacent frames.

BTW, with an electronic shutter, there should be very little (if any) gap between frames.  Some CCDs with electronic shutters can dump hundreds or even thousands of frames per second, which means that the gap can't be much more than single-digit or perhaps double-digit microseconds, either of which would almost certainly be completely ignorable.

As far as I can tell, the hard part is not the sensor side; it's being able to dump ten times as many RAW-sized images to the flash card so that such post-processing would even be possible.  It's almost certainly infeasible right now, but I'd expect it to be pretty easy to do in just a few years.  It could be substantially longer before cameras would have fast enough CPUs to do that sort of processing internally, of course.  Alternatively, it might be possible sooner with the use of some sort of perverse RAW-MPEG encoding in which each subsequent frame in the set is described relative to the first, but the compute power required would be... considerable.

As an added bonus, with an electronic shutter, the camera could examine a few shots before and after the moment when the user presses the shutter like an iPhone does, choosing the least smeared, and defaulting to using that one as the base frame for correction purposes.  Whether shots taken before the lens fully focuses are useful or not is a different question, but I figure that by the time we see something like I'm describing, we'll probably also have light-field sensors that will make those shots almost usable....  Or not.  Hard to say.

This sounds conceptually along the same lines as lytro...capture as much information in an exposure as possible, and deal with everything else in post. It is an interesting idea, but it is actually a fairly significant shift from how photographers thing about things now. I am not so sure how viable allowing the camera to control the actual exposure time really is.

In my case, I expect to know exactly how long the shutter is. It isn't just about compensating for or eliminating subject motion blur, it is more about compensating for camera shake (yes, even with IS or on a tripod.) If a photographer expects an exposure to be a known tiny fraction of a second, but the camera decides it will be a much larger fraction of a second, the likelihood of the camera user moving the camera themselves in a detrimentally significant way is very real. The camera, rather than the photographer, now determines how long the shutter is "open" (mechanical or electronic), rather than the photographer, and that is a hidden quantity...the photographer doesn't know, and assuming there was some kind of feedback mechanism to allow them to know, it is still a very different way of performing photography, and the chance for human error is very real and significant.

While the idea could, theoretically, allow for infinite dynamic range, I think it would require retraining photographers to think differently...and that is never an easy thing to do.

1334
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 24, 2013, 01:00:44 PM »
As a side note, since it would take an increase to 82% Q.E. for the 7D II to gain a true ONE stop improvement in high ISO performance, we can never hope to see a true two stop improvement. The 7D II, nor any successor, nor any new pro-grade APS-C line of cameras from Canon or anyone else, will ever perform as well as a FF sensor that has larger pixels. So long as the average pixel size for FF sensors remains larger than the average pixel size for APS-C sensors, FF sensors will always perform better at high ISO. Nothing we can do about that...its just physics.

Well, there are a few tricks that Canon could do.  For example, if a camera used a series of fast exposures, the camera could do motion vector analysis on various parts of the image, then add them programmatically after compensating for camera and subject motion, resulting in roughly the same image as you'd get with the shorter shot length (blur-wise), but with the SNR of the longer shot length.  However, that's way beyond the realm of sensor tech.  :)

How would that work with a selectable shutter speed, though? I mean, if I as the photographer chose a 1/1250s shutter speed, a single exposure that long is going to be better than multiple separate exposures blended together. You'll lose light in the interframe time as well, so gain would have to be higher...

You're assuming a mechanical shutter.  Consider a vertically stacked sensor that can push its value down to a buffer deeper in the silicon or, for simplicity, an interline transfer design.  You can then sample the image with no rolling shutter (bette for video) and no delay between shots.  If a mechanical shutter is desirable for some reason, open it before the first frame and close it at the end.

It matters not whether the shutter is mechanical or electronic. What matters is that the PHOTOGRAPHER selects the EXPOSURE TIME (shutter speed). Shutter speed is shutter speed, regardless of whether the shutter is mechanical or electronic. If the photographer chooses a 1/2000th shutter speed, then that is AS LONG AS the camera can expose. Trying to make a better exposure by taking several short exposures within that 1/2000th window is likely impossible. At the very least, there is going to be some lag time for read or "ship the charge off to a buffer" between each partial exposure. That lag time is going to cost you light. Because shutter speed is a user selectable quantity of time, gathering light for that total time is the best we can do.

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EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 24, 2013, 04:09:28 AM »
Thanks for the shared enthusiasm, jrista.  My spirits aren't easily dampened.  I do like to make the best informed decisions and that means sifting through some threads with misinformation and using discretion.  It is usually possible to discern who really knows what they are talking about.  Of course there are always differing opinions and that's fine. 

Somehow I can't believe I could handle the 600 F4 handheld for more than a few seconds.  On the other hand the 300 is very manageable and that's important to me since I like to hike through the bush and have maximum mobility.

At any rate I'm understanding better why so many folk are waiting for the 7D upgrade.  Do you think trying my friends 70D with my 300 would represent something close to what I'll likely get with the 7D2?  That seems to be a pretty impressive camera.

Jack

Using the 70D will give you an idea of what it is like to work with a crop factor, and the current 19pt AF system. The pixel density is ok, 18mp, but the key thing is the 1.6x crop factor (which affects your FoV, and is a part of the added "reach"). You will most likely notice the drop in IQ...that old 18mp sensor is WAY past its age, and desperately needs to be replaced. It isn't anywhere as good as the 6D sensor.

You should also get a feel for the higher frame rate. That is one of the key areas that is improved, and it is really nice having a high burst rate. I don't know what the 70D buffer depth is, however on the 7D, I currently get ~35 frames before slowdown, which is another huge boon (especially for BIF).

So, anyway, yeah give the 70D a try. It'll give you an idea about a few things. The 7D II should really have a major boost to IQ, so you wont' get an idea about that, but the crop factor and frame rate will probably come as a bit of a surprise.

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