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Messages - jrista

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1366
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 17, 2014, 10:49:04 PM »
Your problem is that your thinking in terms of sky and frond, rather than waveform A and waveform B. If you decide to think of the problem as sky and fronds, then yes, you just have sky and fronds. You have to change your mode of thinking. It isn't sky and fronds interacting to produce...sky and fronds. It is waveform A and waveform B interacting to produce waveform AB' (which, yes, if you "imaged" waveform AB' you would have sky and fronds...but it would be sky and fronds in an entirely different and unique pattern that did not represent A or B distinctly...it would only represent aliases of A sky and fronds and B sky and fronds....does that make sense?)

I'm talking in terms of a general concept. As I said before, it depends on how you think about the problem. You can think of it as real-world objects, or you can think of it as something else...as discrete waveforms that interact. Generally speaking, of course...I am talking about moire in the abstract, not necessarily the specific. I was trying to demonstrate the concept at large.


Strictly speaking though those frond type and lines overlayed over lines moire patterns are not interfering waveforms though so the moire there really is not wave interference even in a general sense and it's something different (although there are direct similarities to what you'd get from a matched set of wave interferences, but it's different and you don't get the fringing and stuff and so on, you could 1:1 match the center point of the black parts and white parts or centers of the overlapped fronds and centers of the 'overlapped' sky parts to the very peaks and very troughs of matched interfering waveforms though).


They are a waveform, when "observed" as an image.You don't need a camera to think of things in different conceptual models...everything you see could be considered as represented in spatial waveform space. Technically speaking, rather than strictly speaking, everything in the universe exists with different representations in different conceptual models, and each one is valid. Anyway, this discussion has gone way off topic, so....


But the moire pattern isn't strictly a waveform interference pattern. I mean just go to the even simpler thick parallel black lines of slightly different spacing on transparencies and overlay them in various ways and look at the moire.  That's not classical waveform interference. The moire can be directly related in ways to waveform interference but a true waveform interference pattern of closest relation isn't the same.


The lines of your transparencies are part of a wave. The lines themselves, say black, are the "trough" of a wavelength, where as the transparency next to it is the crest. Moire occurs because you are overlaying two waveforms. Just because they are lines on a paper does not mean they cannot be modeled as a spatial frequency...a spatial frequency is exactly what they are. Thick black lines separated by thick bands of transparency is a wave of lower frequency, while thin black lines separated by thin bands of transparency are of higher frequency. This image from Norman Koren's site demonstrates:



Just a bunch of black and white lines, right? No, it's not...depending on how you model or observe the information, it is both lines, AND it is a wave. AND it's also a pattern. The red plot at the bottom models those lines differently than how we classically see them. ALL THREE representations (cage, wave, pattern) are correct and valid...simultaneously. Here is a visual example of moire in reality, caused by the interference of two parts of a monkey cage at a zoo (this moire has nothing to do with the sensor, as the patterns are all clearly much larger than sensor pixel size):



The monkey cage is no different than Norman's diagram...it simply exists in more dimensions rather than one. It all depends on how you decide to mentally and conceptually observe the information your eyes are seeing. Yes, it's just a monkey cage. But that cage's structure can be represented by a wave, as can the moire pattern produced by overlapping parts of the cage.

The nice thing about reducing all this stuff (despite the fact that it is very different real-world things like lines on transparency, monkey cages, pixels on a sensor, etc.) to waves is that you then have a single conceptual mental model with which to work with. ALL interference, therefor, is ultimately the same thing, can be modeled the same way, processed with the same mathematics, etc.

1367
Software & Accessories / Re: Adobe Lightroom for iPad Coming Soon
« on: January 17, 2014, 08:40:58 PM »
A yearly cost of $99 is WAY too much. Adobe has their pricing model jacked way up to 11, and they don't seem to realize it. The average cost of owning Adobe products in the past was a fraction of what it costs today for the average photographer and freelancer. While it maybe as cost effective for monstrous corporations, Adobe is seriously alienating their long term loyal individual customers with this inane pricing model. The per-app prices should be $3 - $5 per month, with maybe a few key apps like Photoshop at around $10 per month (simply because of the sheer volume of functionality they provide, which is indeed rather extensive).

If Adobe sticks with these ludicrous prices, someone is going to realize there is a massive and growing population of potential consumers for high quality products in the photographic editing segment, and they are going to deliver the goods at a reasonable price, at a rather massive long term cost to Adobe's bottom line. There is no way Adobe makes enough off of the big corporate users to support their business model if they lose the majority of their individual customers...which really begs the question:

Why are they trying to suck us dry like this?

It really doesn't make sense...

1368
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 17, 2014, 04:57:46 PM »
Your problem is that your thinking in terms of sky and frond, rather than waveform A and waveform B. If you decide to think of the problem as sky and fronds, then yes, you just have sky and fronds. You have to change your mode of thinking. It isn't sky and fronds interacting to produce...sky and fronds. It is waveform A and waveform B interacting to produce waveform AB' (which, yes, if you "imaged" waveform AB' you would have sky and fronds...but it would be sky and fronds in an entirely different and unique pattern that did not represent A or B distinctly...it would only represent aliases of A sky and fronds and B sky and fronds....does that make sense?)

I'm talking in terms of a general concept. As I said before, it depends on how you think about the problem. You can think of it as real-world objects, or you can think of it as something else...as discrete waveforms that interact. Generally speaking, of course...I am talking about moire in the abstract, not necessarily the specific. I was trying to demonstrate the concept at large.

Strictly speaking though those frond type and lines overlayed over lines moire patterns are not interfering waveforms though so the moire there really is not wave interference even in a general sense and it's something different (although there are direct similarities to what you'd get from a matched set of wave interferences, but it's different and you don't get the fringing and stuff and so on, you could 1:1 match the center point of the black parts and white parts or centers of the overlapped fronds and centers of the 'overlapped' sky parts to the very peaks and very troughs of matched interfering waveforms though).

They are a waveform, when "observed" as an image.You don't need a camera to think of things in different conceptual models...everything you see could be considered as represented in spatial waveform space. Technically speaking, rather than strictly speaking, everything in the universe exists with different representations in different conceptual models, and each one is valid. Anyway, this discussion has gone way off topic, so....

1369
EOS Bodies / Re: Hybrid Viewfinder Coming To Canon DSLRs? [CR1]
« on: January 17, 2014, 12:55:30 PM »
Hi,
    I use the Kenko Pro 300 DGX 1.4x (blue dot version) on my 400mm F5.6L and 6D all the time and the bokeh look normal to me... focusing speed is only slightly slower. Anyway, bokeh is cause by the aperture blades, right? So the quality of the bokeh should be determine by the lens design.

   Have a nice day.

Boke is determined by the whole lens design, not just the number of blades in the aperture. The shape of the blur circle is ultimately determined by the number of blades, and whether they are rounded or not...but the QUALITY of the blur is determined by the quality of the lens design, it's glass, what kinds of aberrations it has, etc. It is quite clear that the Kenko design is not as high quality as the Canon design, as there are definitely differences in the quality of boke. Canon blur circles are much cleaner.

1370
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 17, 2014, 05:28:16 AM »
Quote
The fronds of a palm splayed against a bright sky can be observed as a wave. The fronds are the troughs, the sky are the crests. A complex wave can be used to describe that "oscillation" of light blue and dark green. Cross two palm fronds over each other, and you create an interference pattern.

But as I said way up above, just to start, when you have sky over sky you get just sky and when you have frond over frond you have just frond and when you have sky 'over' frond you have frond and when you have frond over sky you have frond.

Your problem is that your thinking in terms of sky and frond, rather than waveform A and waveform B. If you decide to think of the problem as sky and fronds, then yes, you just have sky and fronds. You have to change your mode of thinking. It isn't sky and fronds interacting to produce...sky and fronds. It is waveform A and waveform B interacting to produce waveform AB' (which, yes, if you "imaged" waveform AB' you would have sky and fronds...but it would be sky and fronds in an entirely different and unique pattern that did not represent A or B distinctly...it would only represent aliases of A sky and fronds and B sky and fronds....does that make sense?)

I'm talking in terms of a general concept. As I said before, it depends on how you think about the problem. You can think of it as real-world objects, or you can think of it as something else...as discrete waveforms that interact. Generally speaking, of course...I am talking about moire in the abstract, not necessarily the specific. I was trying to demonstrate the concept at large.

(extra not totally relevant stuff:
It gets tricky as some types depends at the resolution they are plotted at since plotting the same 1 pixel wide function on a lo-res screen might cause moire of one sort and of a slightyl different pattern at a different res screen and not at a very high res screen since then the moire happens from the plot interacting with the sampling of the screen.

And some of the parallel lines of different frequencies might look like it goes black and white and gray from a distance but clearly nothing but pure black and pure white closer in (although you might still have a pattern where the thickness of the black and white varies, although if you plotted it at a much higher resolution but kept the thickness of the black lines always to one pixel it could go away in terms of any difference in thickness of black portions although the distance between those skinny black lines could form a pattern).)

I think your overcomplicating things. Moire is simply pattern interference. It isn't about things going black or white or gray. The question is...when you have the product of waveform A interfering with waveform B as new waveform AB'...if you sample AB', does it accurately representwaveform A distinctly, or waveform B distinctly, or something that technically isn't actually representative in either? The answer to that question is technically that every sampled point in AB', regardless of how many samples you take, represent AB'. They are aliases of A and B, as AB' is not an exact replica of either, it is the product of their interference. It is something entirely new, comprised of aliases from the originals (think about that...alias...in another context, an alias would be a different identity that represents someone, but isn't actually their real identity, right?) That's all moire is...aliasing as a result of pattern interference...be it in the real-world (as is the case with some of the feathers in my images) or the result of image interfering with sensor.

Anyway...it's time for bed for me...I really need some sleep (insomnia is kicking my ass lately... :\)

1371
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 17, 2014, 03:11:36 AM »
I know for a fact that LR uses a form of AHDD. DPP tends to produce sharper results, however it is more susceptible to aliasing. LR tends to produce really clean edges, but it also produces slightly softer results.


Hmm I've actually found that I can get more detail out of ACR than DPP (although I haven't used DPP since the convolution stuff, but barely at all) and ACR seems prone to created stair-stepped fine lines from some lenses.

ACR seems to be much more prone to color moire aliasing than DPP, but DPP seems to be much more prone to zipper artifacts. ACR is also prone to severe stair-stepping jaggies at times and it can be really bad at timed with say orange leaves against a blue sky. C1 avoid the stair-steps but seems prone to dotted line type artifacts (where a solid, fine line may turn into a dotted line or a line with spurious stray pixels hanging off or certain solid patterns turn into randomly dotted checkerboards). Each definitely has some issues.

I'm not saying that ACR can't get more detail...just that it's not quite as intrinsically sharp as DPP (without any adjustments beyond simply demosaicing.) The aliasing issue with DPP is pretty consistent, doesn't require any specific kind of scene...sharp edges are usually aliased a bit, regardless. In my experience, fine edges and lines with ACR are usually very clean and crisp, without the endemic jaggedness that occurs frequently in DPP. Sure, there are some difficult cases that fall outside the realm of normal for any algorithm, but AHDD is one of the better demosaicing algorithms, and DPP clearly does not seem to use it.

I wonder if we are not using different terms. Maybe we are meaning two different things by jaggedness. Maybe you are using that to refer to what zipper artifacts (like the jaggy teeth in a zipper) while I've been using it to refer to thin lines that look jaggy in the sense that they are stair-stepped and maybe we actually both agree?

There is aliasing, and there is moire. Moire is a form of aliasing, aliasing is not moire (it encompasses moire, other forms of aliasing.) I think you are just thinking about aliasing in general, which yes, is the stairstepping along sharp edges in the absence of AA. Moire is very specifically defined as the effect (a pattern) caused by interfering waveforms, which is a kind of aliasing (the aliases in a moire pattern are "fake" information generated by waveform interference, as each resolvable point does not represent real-world information.)

Moire exists outside of the world of digital cameras. Think of looking through two sets of railing, bird feathers overlapping and so on. If you're there looking at it with your own eyes, the moire is visible. Therefore this particular type of moire is not camera induced.

It very well can be. It's not intrinsically there, if the eye sees it, it would only see it at certain particular scales of distance.

Moire is the result of pattern interference. It doesn't really matter the scale, the effect is scaleable. If you have two crosshatch lattices in your yard, and you were able to line them up relative to each other, the two would create a moire pattern. All that is necessary for moire is for patterns with similar frequencies to interact and interfere with each other. Palm fronds crossing over each other, two nets overlayed on top of each other, bird feathers crossing over each other...all of these create moire. Moire is a consequences of waves in nature (no, not water waves), waveforms interacting and interfering to produce an entirely different "output" waveform that does not resemble any of the originals.

Moire doesn't come from light wave super positioning and interference. That doesn't even make sense, since you can print out large thick lines on a piece of paper and create it, that is pattern frequency and scale interaction and it's all positive additive.

I never said moire came from light waves at all. It comes from WAVES. Waves exist in all kinds of spatial media, it implicitly has nothing specifically to do with just light.

OK, well when you said not water waves and so on I thought you meant light waves, my mistake.

But it almost sounds like you are at least trying to say that these spatial moire patterns are simply coming from interfering wave patterns? Or maybe that is not what you mean to say?



And yeah well it can both be there intrinsically or not, depending, but not all moire on feathers and stuff is intrinsic, I'd guess that most moire in photographs isn't coming from something intrinsic in the scenes, although it could be.

It depends on how you look at things. Waves are everywhere. They don't just exist as sound or light or as longitudinal and transverse waves in water. Waves are mathematical. They define things that oscillate. EVERYTHING oscillates.

Atoms vibrate. That's oscillation. That's a wave. It doesn't "look" like a sine wave of you sit there and observe an atom vibrating, but when you plot the position of the atom in a given dimension over time, you DO have a sine wave (with some amplitude, frequency, and phase.)

Wind is a wave. If you think about it, wind occurs in blasts or pulses. Even the lightest breeze is a sine wave of some form or another. This can be seen when a breeze moves through a playground...just look at the swings. They don't all move in unison...they move as though they were attached to a string that someone was sending pulses down, like when you attach a string to a doorknob, take one end in your hand, and move your hand side to side. (Wind is actually also one of the primary causes for waves in water...the sine wave formation of water waves is often given rise to by the sine wave oscillation of air moving across it.)

The fronds of a palm splayed against a bright sky can be observed as a wave. The fronds are the troughs, the sky are the crests. A complex wave can be used to describe that "oscillation" of light blue and dark green. Cross two palm fronds over each other, and you create an interference pattern.

Same thing goes for the feathers of a bird. Each barb is a wave crest, and the space between them is a trough. Overlay multiple feathers on top of each other, and you have a complex moire pattern.

The vibrating of the compressor in your refrigerator that you feel in the hardwood floor via your feet...that's a wave. Blinking light...the blinking, not the light, is a wave (and, of course, the light itself is a wave.) Waves are everywhere. Even the complex detail of a photograph is produced by waves...two dimensional waves, in this case, described by a Fourier series (very complex system of waves in a multitude of frequencies that interfere to produce a complex non-random result), which is why we can end up with moire when the SPATIAL waveform (not the light waves, but spatial waves) of the image resolved by a lens interfere with the ordered spatial grid of an image sensor.

Waves. More than just light, sound, and water. ;)

1372
Animal Kingdom / Re: Show your Bird Portraits
« on: January 16, 2014, 08:26:06 PM »
Great comments jrista.  So you'd say my subjects are a little underexposed I take it.  Yes, the posibilities are great with some creativity as you've suggested.  Again, thanks for the encouragement!

Jack

Aye, underexposed a bit. You should ETTR, expose to the right. In just about every exposure except those of overall low-key scenes that only contain darker tones, your histogram should always reach about half-way to two-thirds into the rightmost vertical bar. If your image is higher key, then the bulk of your histogram will bunch up towards the right (but, it shouldn't actually ride up the right hand edge unless you are purposely blowing some highlights, like the sky).

If you want to learn exposure from the absolute best, buy Art Morris' book "The Art of Bird Photography". His chapter on exposure explains it better than anything I've ever read, anywhere. His techniques for pre-setting exposure before you actually start taking pictures are exquisite. After reading his book (even after just reading that one chapter), you'll have a whole new idea of how photography works.

(NOTE: You want to buy the original BOOK, not the eBook. The newer eBook has some good content, but it is the old classic book that actually has the good information on exposure. At the moment, to my knowledge, the only place you can buy this book is on Art Morris' web store.)

1373
Animal Kingdom / Re: Show your Bird Portraits
« on: January 16, 2014, 07:44:12 PM »
Skatol, a friend and I just sat on the deck for 1/2 an hour talking and got lots of shots.  Now I'm thinking I'd like some different backdrops so I guess that's the downside of this approach.  And the results tend to look a little "sanitized".  If it's sunny tomorrow I'll try the bare 300.  However, so far there are only 4 models that are volunteering for the shoot, so this could get a little boring in the long term! ;)

Guess prospective models will need to be paid more! 

Jack

Backdrops aren't a downside, they are the upside. Your setups should be mobile. Move them to wherever you want them, with whatever kind of backgrounds you need!! You can even create backgrounds by setting up things at a distance behind (and even in front of) your setup. When it comes to bird setup photography, the possibilities are almost infinite.

Regarding your shots. Looks like you are exposing for the sky. Don't do that. ;P Expose for the bird. It's ok if the sky is blown, the sky isn't your subject.

1374
Animal Kingdom / Re: Show your Bird Portraits
« on: January 16, 2014, 07:38:24 PM »
First day of trickery.  They love my stump! ;)

I chose 300 X1.4 and 1250th and ISO 800  F5.6 typical

Jack

Very cool.  Think I'll have to try something like this.  At least my wife wouldn't have to worry about me being away from home all weekend.

Don't forget, you can create setups out in nature as well. I get a small selection of Colorado's 400+ bird species in my yard. I have to go elsewhere to photograph a greater species diversity. Alan Murphy has a bunch of tricks for setups in nature as well. I keep meaning to try a setup to get some good photographs of the local Pheasants (which are notoriously difficult to photograph as they are always hiding in the grass and brambles.)

1375
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 16, 2014, 07:29:44 PM »
I know for a fact that LR uses a form of AHDD. DPP tends to produce sharper results, however it is more susceptible to aliasing. LR tends to produce really clean edges, but it also produces slightly softer results.


Hmm I've actually found that I can get more detail out of ACR than DPP (although I haven't used DPP since the convolution stuff, but barely at all) and ACR seems prone to created stair-stepped fine lines from some lenses.

ACR seems to be much more prone to color moire aliasing than DPP, but DPP seems to be much more prone to zipper artifacts. ACR is also prone to severe stair-stepping jaggies at times and it can be really bad at timed with say orange leaves against a blue sky. C1 avoid the stair-steps but seems prone to dotted line type artifacts (where a solid, fine line may turn into a dotted line or a line with spurious stray pixels hanging off or certain solid patterns turn into randomly dotted checkerboards). Each definitely has some issues.

I'm not saying that ACR can't get more detail...just that it's not quite as intrinsically sharp as DPP (without any adjustments beyond simply demosaicing.) The aliasing issue with DPP is pretty consistent, doesn't require any specific kind of scene...sharp edges are usually aliased a bit, regardless. In my experience, fine edges and lines with ACR are usually very clean and crisp, without the endemic jaggedness that occurs frequently in DPP. Sure, there are some difficult cases that fall outside the realm of normal for any algorithm, but AHDD is one of the better demosaicing algorithms, and DPP clearly does not seem to use it.

1376
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 16, 2014, 07:25:36 PM »
Moire exists outside of the world of digital cameras. Think of looking through two sets of railing, bird feathers overlapping and so on. If you're there looking at it with your own eyes, the moire is visible. Therefore this particular type of moire is not camera induced.

It very well can be. It's not intrinsically there, if the eye sees it, it would only see it at certain particular scales of distance.

Moire is the result of pattern interference. It doesn't really matter the scale, the effect is scaleable. If you have two crosshatch lattices in your yard, and you were able to line them up relative to each other, the two would create a moire pattern. All that is necessary for moire is for patterns with similar frequencies to interact and interfere with each other. Palm fronds crossing over each other, two nets overlayed on top of each other, bird feathers crossing over each other...all of these create moire. Moire is a consequences of waves in nature (no, not water waves), waveforms interacting and interfering to produce an entirely different "output" waveform that does not resemble any of the originals.

Moire doesn't come from light wave super positioning and interference. That doesn't even make sense, since you can print out large thick lines on a piece of paper and create it, that is pattern frequency and scale interaction and it's all positive additive.

I never said moire came from light waves at all. It comes from WAVES. Waves exist in all kinds of spatial media, it implicitly has nothing specifically to do with just light.

And I mean you can photograph some suit with one sensor from one distance and if the scale is right you get nasty interference but then move the camera back or forward and it changes or goes away so it's not like you can say the suit had some intrinsic moire. It was the combination of the pattern from the suit projected onto the sensor at specific distance that did it. So in that sense it is not intrinsic or scalable. I mean you have created the moire in the captured image maybe it's sort of scalable at that point within reason.

Moire can be created by patterns in the image interfering with the pattern of the sensor, obviously. That's why we have AA filters. Certainly, you can move closer or farther from your subject, and change the moire effect created, assuming you have that option given the composition your aiming for. That is just one means of creating moire, though. Moire does not need a sensor to occur...any repeating waveforms with the right frequencies that can interfere with each other will produce moire. You can plainly see it with your own eyes, without the existence of a camera, in countless real-world situations. If you photograph such a thing, the moire will be in your photo, in that case not as a consequence of interference with the sensor, but simply because it existed in the real world.

In the case of my bird photos, there are a few spots of moire, because it existed in reality, not as interference with the sensor array.

1377
EOS Bodies / Re: Canon 7D - Vertical Banding Noise
« on: January 16, 2014, 04:02:33 PM »
Not good. Looks like one of the readout channels on the sensor has gone bad.

At least one. The 7D has eight channels...looks like maybe two of them went out, given the spacing of the missing columns.

1378
EOS Bodies / Re: 7D Mark II on Cameraegg
« on: January 16, 2014, 03:58:23 PM »
I am hoping the 7D2 is to the 7D, as the 5D3 was to the 5D2 and is compelling enough to make me want to upgrade. I am specifically looking and hoping for a sizable improvements in DN, High ISO Performance and the 5D3 AF system or similar.
I am so disappointed with the 7d by today's standards that any improvement will be worth the upgrade.  Just show me where to sign...

The problem Canon has with the 7DII is that it will certainly rob sales from the 1Dx. If 10 fps @ 18mp with 61 point AF is true then it really will be a 1.6x cropped 1Dx. I suspect that Canon will leave the IQ much the same as the 70D, it's got to hold back on something for this camera.
Naturally we all want a camera with less video compromises (the 7D has a really strong AA filter), far better noise handling threashold and a DR to match the current Sony Exmore CMOS sensors. But I seriously doubt that Canon will invest in sensor tech for this camera and I think they will brin in the new tech for the 1Dx replacement or it's high MP cousin.
I don't think  the 7D II rob sales from the DX. I've been saving for the 1 DX for many months now and on the verge of the getting one. I did have a fleeting thought maybe I wait for the 7D II I can then purchase that along with the 5D Mark III. I'm thinking maybe I can have the best of the both worlds but I held that 1DX again and felt the solid build. There's no doubt I'm getting the DX. The 1 DX and 7DII will cater to two different markets IMHO...

I occasionally wonder if I will be hit with the 1dx bug.  My logic in the past has been... if you have the money and your lenses are really good, the logical step is to improve your body. 

But there are also times when I use my daughter's old xti and I think... this generations old body can get me wow photos too... so why do I have a $3000 body and by extension, why would I ever need an $8000 body.

And I know the answer... because I can't use the xti all the time with a tripod in ideal light.  But it does still bother me just a little. 

If you don't mind me asking, what does the 1dx bring to the table that a 5d mkiii can't provide?  I know the specs, but I'm just curious what you value to be worth the extra cash?
Sure, I want to be able to expand into sports & wild life photography. Don't get me wrong the 5D Mark III is a great camera and it will handle most of my needs but it just doesn't have the blazing fps. I pondered this for countless months and I won't be purchasing aonther body for a while after this one. I currently own a 5D Mark II.

The 7Ds AF system has an intrinsic jitter that negates a lot of it's FPS advantage. Even when locked onto a subject, there are small changes in the actual AF position every single frame, which can kill that "one best frame". Overall, the keeper rate with the current 7D falls around 4-5 per second, at best. The 5D III has a vastly superior AF system, putting it in the same bucket, and possibly even beating the 7D with a consistent 5-6 keepers per second (it's AF system rarely misses and doesn't seem to jitter.)

Unless Canon actually puts a better AF system in the 7D, and guarantees that whatever AF system they do put in it doesn't have that jitter, the extra FPS isn't going to be all that much of a lead over the 5D III.

1379
Animal Kingdom / Re: Show your Bird Portraits
« on: January 16, 2014, 01:14:11 AM »
Jack, Thanks!  If I had stopped shooting to take the 1.4X off, I might have gotten everything in the frame.  Was really concerned that the required movements would cause the hawk to fly off but after it was over, I believe it might have been possible.

I say stick with your instincts in the field. Hindsight doesn't tell you as much as having that in-person presence does. I've often been in the same situation, thinking I could have taken off the TC...but usually, the birds I photograph just don't sit still for long, and taking the time to switch the TC in the middle of photographing an interesting sequence usually results in losing the moment.

1380
EOS Bodies / Re: Hybrid Viewfinder Coming To Canon DSLRs? [CR1]
« on: January 16, 2014, 01:12:35 AM »

It's a Bower. I think it's the same generic brand as Rokinon/Samyang.

It may not be the Bower TC that causes the IQ loss. I mean, it will cause some, but the 100-400 sucks even with the EF 1.4x III (which it doesn't even function properly with), and while it functions properly with the much-loved Kenko Teleplus Pro 300 GDX 1.4x TC, the IQ still sucks (a little bit more than the Canon 1.4x, but the differences aren't huge.) I think it's just that the old 100-400mm lens design was built in the film era, at the early dawn of the digital era, and the bar for quality wasn't as high back then. It is most definitely a softish camera at f/5.6 and f/6.3, and only really starts to sharpen up by f/7.1 and f/8. With a TC, you would be at f/11, which imposes a significant hit on either shutter speed (which increases softness from camera shake) or ISO (which packs on the noise, especially on a 7D).

It is possible that your $80 Bower TC is just fine, and that it just doesn't pair well with 100-400 (because, well, NO TC pairs well with that lens. :D )
There's probably something to do with the age of the 100-400 and its dislike of TCs, but I've tried the Bower TC on my old 28-135, and the TC definitely degraded the sharpness there too.  Maybe I got a bad copy.  I imagine the Kenko brand is a tad better than Bower.  I hear the Bower/Rokinon/Samyang conglomerate makes fairly good lenses, so maybe they just don't make good teleconverters.  It's probably very difficult to optimize a teleconverter for a bunch of very different lenses.

The Kenko is decent, but it is definitely not as good as the Canon TCs. It allows just barely visible improvements when attached vs. when not attached. Subjects are definitely larger in the frame, but you don't get the same kind of increase in overall detail as with a Canon TC.

Something else I've noticed with the Kenko TC...boke circles look TERRIBLE. They have this funky warped star effect which just looks rather bad, so I don't really use it much anymore. It's great though, for people who want f/8 AF on camera bodies, like the 7D, that don't normally support it (so the boke issue just doesn't matter in those cases). It does allow f/8 AF, and in good light, even the 100-400 will focus automatically, albeit slowly.

If you have a good lens, and a body that supports AF at the smaller apertures, get a Canon TC. No question they offer better quality. If you have a body that does not support f/8 AF and you need it (probably best with the 400/5.6 L prime), the Kenko is the best bet. (Actually, the Kenko MC4 seems to produce better IQ overall than the Kenko Pro 300 DGX, so I actually recommend getting that one...I simply couldn't find one for sale when I bought mine.)

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