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Messages - jrista

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1171
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 04:03:03 PM »
BTW.... I decided to try to take a picture of the space station passing overhead with my SX-50 (EVF)... I could not spot it....

 ;D ROFL!!  ;D

1172
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 02:45:52 PM »
NEED what OVFs offer...unlimited dynamic range

http://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm

Lets just put this one to rest. Your eyes do not have unlimited dynamic range, it's only about as good as your camera.
Modern cameras have much better night vision (ISO well above 1000).
Also, I have yet to hear a good argument for why looking at the environment with your eye through the lens helps you take a better picture.

Sorry, but I can see FAR more dynamic range with my eyes than my camera sees. Whether it is my brain blending "frames" to achieve it, or individual exposures...the mechanics of how don't matter. When people say 8-11 stops is similar to 10-14 stops, they are ignoring the fact that a stop is factor of two. It's a difference of 8 to 64 TIMES greater tonal range. My eyes see at a minimum 14 stops...from clouds to bark detail in the shadows, which is probably closer to 20 stops than 14 stops. It doesn't matter that my brain is "doing all the work" to blend the information the biological device that is my eye actually receives...I SEE it.

Now, I don't say my eye can see unlimited DR. However an optical viewfinder is not going to limit you further. The OVF itself is effectively unlimited when it comes to DR...so my eyes can operate at maximum capability when looking through an OVF. When it comes to shooting in lower light, with my eye to the viewfinder, being able to utilize the full 24 stop dynamic range potential of my eye...i.e. allow it to adjust to the dimmer light so I can clearly see my subject without noise for the purposes of framing and composition, regardless of whether my camera could see the same thing when read out at 60fps, is a huge boon. Jack up the gain on an EVF or Live View...and what do you get when it comes to darker scenes? Dark...with a lot of noise. This problem is even exacerbated further when doing something like astrophotography...you can't see the night sky in an EVF or on Live View. You might be able to see some of the much brighter low magnitude stars, but overall you can't compose. However I can look through an optical viewfinder and see everything as if I was looking right up at the sky without a camera in front of me. The dynamic range of the human eye is VASTLY superior to the dynamic range of a camera (and an EVF.)


1173
My first bird photos with the Tammy! Here is the very first shot taken. 5DIII, f/8 iso640, and 600mm, a greylag goose at Fowlmere in Cambridgeshire.

The AF is very reproducible (A1 servo), much, much better than the 100-400L on 7D and better than on the 5DIII.  The full-frame of the goose is reduced to 1200x800. The head is 100% crop.

Congrats! Detail looks great!

Have you tried any tracking for BIF yet? That was always a weak spot with the 100-400L and 7D IMO. It is so much better with the 600mm, but still not as good as the 5D III.

I love the Greylag Goose. Sometimes a few of them hang out here in Colorado. They tend to mate with Canada Goose, and you get some very interesting offspring. I actually need to head out to Duck Lake in City Park near Denver. This is about the time that the Cormorants and Greylags show up. The Cormorants nest every year on this island in Duck Lake...to the tune of a couple hundred (and plenty more when all the hatchlings come). It's still pretty cold, but I wonder if they are already here...

1174
I wasn't just thinking noise, I was thinking much better technique, a bigger magnification needs more support to have the same camera shake (even on the best tripods), any system aberrations are magnified more, AF becomes more critical etc etc.

The crop factor or additional magnification of smaller pixels compared to bigger ones entails at least the linear factor improvements in everything, AF, aberrations, noise, shutter speed, support etc etc.

I believe, very strongly, that is why the 1Dx has been so wholeheartedly embraced over the 1.3 crop 1D MkIV, a camera that was pretty much universally loved by everybody and had that all important sports "crop factor", even when the 1D MkIV has a much higher pixel density.

Oh I don't doubt it. I drool over 1D X IQ all the time. Despite how good the 1D IV was, there is still a clear difference between it's IQ and the 1D X IQ. The dynamic range of the 1D X (I don't mean the kind that gives you more editing latitude, I mean the reduction in photon shot noise at all levels) really can't be beat. Not unless you reduce pixel size even more.

Besides, if your spending $5000 to $7000 on a camera body, you probably already have or are easily able to get a $10,000+ supertelephoto lens and teleconverters to go along with it.

1175
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 01:23:49 PM »
Actually, that doesn't matter. You still face the problem, because Canon is a Japanese company, and most of their manufacturing occurs there. The Japanese regulate the economy within which the cameras you buy are built. You have to not only deal with their regulations, you have to pay for them too, if you buy cameras made in Japan. :P

So Japanese legislation forbids us to place more than ... what? ... two batteries in our cameras? I don't really understand this part of your argument. Sure, I'm all for removing certain hazardous chemicals from batteries, but said removal also removes it from batteries for use in "traditional" DSLR camera. Obviously I'm seriously missing something here ...  ???

Let me put it this way. While Canon might end up with more empty space inside of a 5D III camera body once they make it "mirrorless", they wouldn't necessarily be able to easily fill it with more battery. The likelihood that they keep using their current battery designs is very high, as redesigning the battery wouldn't only involve just the relatively small R&D cost to do so...but also the regulatory burden to make sure that whatever battery they designed conformed to Japanese regulatory specifications. It isn't just chemical makeup, those kinds of regulations usually rather inane and stupid, because it is a politician or his assistant drafting up the laws, neither of whom are ever engineers themselves, and they are basing their regulatory decisions based on not only insight they might glean from some short interviews with engineers, but also environmental lobbies and a whole host of other interests all tugging at each other. In the end you end up with ridiculous things like limitations on maximum amp-hour capacity, maximum physical size, etc. that really do nothing to solve any interested parties problems or concerns...instead it finds the least objectionable middle ground that results in the least amount of complaining from all interested parties...and totally gimps the consumer's options and capabilities. Even as it stands now, the 5D III batteries could be larger, as there are some decent space cavities inside the 5D III body...but they aren't, because of regulatory limitations.

Another example is the 30 minute limitation on video recording length. There is ABSOLUTELY ZERO reason to limit how long a video clip can be in a DSLR with video capability. It is most assuredly not a technological issue for DSLRs to stop recording at 29:59. The sole reason that limitation exists is because the EU and I think one other regulatory region require it, and as far as I gather, that regulation is based on lobbies from dedicated video recording device manufacturers for things like camcorders who wanted to squelch any legitimate competition from DSLRs (i.e. they were too weak to innovate and compete in an open market, so they went running to nanny government to lay on the spankings and send to their rooms on the only competition they have faced in a decade... :P)

Problem is, it's too difficult for manufacturers to build one model for the EU, one model for Japan, and another model without these inane limitations for the rest of the world. So they build one model that fits within the limitations of all the regulations of all the regulatory regions they sell their products in...and everyone regardless of their actual market ends up having to deal with regulations that don't even exist in their own country.

??

No dice. It's my idea and Canon (or Nikon) ain't gettin' it for free.  :-X

Er...whatever...

1176


The magnification that we've been talking about so far is relative magnification in terms of subject size to frame size. It doesn't really matter how big it is in real life in this context. In this context, magnification is referring to the change in relative subject size with a change in resolving power. The change in resolving power can either come from an increase or reduction in focal length, or an increase or reduction in pixel size. Either way, the subject is either magnified or reduced RELATIVE to some chosen reference point. Technically speaking, one need not necessarily involve a frame size...the frame could be infinite. The detail on the subject increases either way...the final images, when observed at 100% size, result in the subject imaged with an increased focal length or smaller pixels will be larger (this, magnified.)

Both definitions of magnification are valid. They just have different contexts within which they are valid.

If you enlarge a square more than another square you are changing the relative magnification. If you say my smaller square is as good scaled up as your bigger square we are not talking magnification, we are talking IQ.

The lens produces the magnification, pixels do not. If you are saying, we consider two different sized things as equal then again, that is not a question of magnification, it is a case of proving the two things are equal, I have proven to myself, and many others, the smaller thing is nowhere near as good as the bigger thing so the entire premise of the discussion is flawed.

All pixels are not equal, for a variety of reasons, it does not further the cause of anything to keep persisting in the crusade that they are.

The latest super tele comparisons are cropping. People are finding that cropping is a viable alternative to TC's and lesser quality longer lenses, something I have been saying against the grain for years. Straight pixels on the subject, the "pixels on duck" meme would have no rebutal for a 400 f2,8 IS MkII getting a sharper shot when cropped as a Tamron 150-600 shot at 600, but I'd bet a lot of money that it would.

Pixel density is a totally spurious, discredited, and fallacious argument. Pixel quality is, and always has been, king.

When you throw non-equal pixel quality into the mix, I totally agree. I think I stated a few times before "all else being equal", but you are indeed correct, smaller pixels are generally NOT equal.

In which case, I totally agree, a 600mm lens on bigger pixels trounces a 400mm lens on smaller pixels cropped.

(I was trying to keep noise out of the discussion though, as that would have just complicated the whole deal...however, seeing as I think the magnification vs. area argument is pretty much settled now, bring on the noise! :P)

Speaking of bigger pixels and less noise...it seems PhaseOne and Hassy finally did it. They put out new MF backs with Sony 50mp 44x33mm MF sensors, that still have 14 stops of photographic dynamic range...plus the increase in signal DR thanks to the larger pixels (which I think are around 5.3-5.5 microns...not as large as a 5D III or 1D X, but larger than any APS-C sensor, and certainly larger than the D800 pixels.) What I would give to have that kind of sensor with a 10fps frame rate, ISO up to 25600, and Canon's 61pt AF sensor! :P

1177
"Linear or transverse magnification — For real images, such as images projected on a screen, size means a linear dimension (measured, for example, in millimeters or inches)."

It's pretty clear that in this case magnification is linear ...  8)

Perhaps people are assuming different contexts. Your talking about a linear change in angular size. I don't dispute the definition of that.

I'm talking about a change in area, "total size", because it is the change in subject size relative to the AREA of the sensor that results in an increase in detail. Not a 2x increase in detail, a 4x increase in detail. In my previous example, the 400mm lens resolves the prairie dog at about 25% of the frame. The 800mm lens resolves the prairie dog at 100% of the frame. That is a 2x change in angular size, but a 4x change in total subject size (width and height).

1178
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 12:39:06 PM »
Well, as always, nothing is so simple.

I've found that most times "experts" refuse to see the obvious solution because it is too simple according to them. I've also found that most times solutions really are very simple. But that's just me ...  ;)

LOL. Well, at least your blissful in our ignorance. ;P

First, when it comes to batteries ...

Yes, in a hyper-regulated society ... glad I don't live in one.  :D

Actually, that doesn't matter. You still face the problem, because Canon is a Japanese company, and most of their manufacturing occurs there. The Japanese regulate the economy within which the cameras you buy are built. You have to not only deal with their regulations, you have to pay for them too, if you buy cameras made in Japan. :P

When it comes to EVFs ... Resolution in EVFs needs to be over 5000ppi in order for pixels to be invisible to the human eye at 1.25" eye relief for 20/20 vision. It needs to be over 12,000ppi in order for pixels to be invisible to the human eye at 1" eye relief for 20/10 vision. However, 12,000ppi is likely impossible, as the pixels would have to be so small, you would be filtering out red light ...

Actually, there's a very simple solution for this problem as stated by you ... only I don't work for Canon (or Nikon), so they can go figure it out for themselves ...  8)

??

1179
As an aside, pixel density has absolutely nothing to do with magnification, nothing, zero, nada. Initially magnification refers to how big the subject is on the sensor compared to its actual size in real life, subsequently it refers to the reproduction ratio, how big is it on screen or in print compared to how big it is in real life, neither of these have anything to do with pixel density.

That is one meaning of magnification in one context. There are multiple contexts within which the term magnification is valid. The magnification you've defined is optical magnification, but not the same kind of magnification we've been talking about so far. For your definition, "magnification" of the lens would be something like 0.15x, where an object a hundred feet away that may be five feet tall is reproduced at 12mm in size on the sensor. This is the kind of magnification that is sometimes published with lens specifications. That is indeed a valid definition of magnification, but it comes with a specific context.

The magnification that we've been talking about so far is relative magnification in terms of subject size to frame size. It doesn't really matter how big it is in real life in this context. In this context, magnification is referring to the change in relative subject size with a change in resolving power. The change in resolving power can either come from an increase or reduction in focal length, or an increase or reduction in pixel size. Either way, the subject is either magnified or reduced RELATIVE to some chosen reference point. Technically speaking, one need not necessarily involve a frame size...the frame could be infinite. The detail on the subject increases either way...the final images, when observed at 100% size, result in the subject imaged with an increased focal length or smaller pixels will be larger (this, magnified.)

Both definitions of magnification are valid. They just have different contexts within which they are valid.

This discussion seems to be about the term magnification and whether it is a 1 or 2 dimensional concept.  Did anybody look up the definition of magnification?  This might be helpful - http://en.wikipedia.org/wiki/Magnification

See my response above. :P

1180
WOW! If you really believe that double the focal length will enlarge the subject by 4x, then I have lost all respect for your skills! Sorry man!
It will enlarge the subject by 2x of course, nothing more, nothing less. Do you even own a camera? Or a lens?

LOL

Well, to be quite frank, I'm not really concerned by the loss of your "respect." I guess I honestly care more about truth and facts than the respect of someone who refuses to acknowledge both when their hit in the face by them.

This is not complicated stuff. It is really basic geometry. YOU SHOULD KNOW THIS STUFF from your high school level math classes! Your still thinking one-dimensionally, as in "An 800mm lens is twice the length of a 400mm lens." Yes, that's true, an 800mm lens is just twice the length of a 400mm lens. But it has 1/4 the FoV!!! Project that 1/4 size FoV onto the same physical sensor area that a 400mm lens projects its 1/1 size FoV onto, and you've enlarged your subject four-fold.

Here is another pretty picture:





Hopefully these three diagrams will completely demonstrate the concept. The first shows the 35mm full frames that a 400mm (orange), 600mm (green) and 800mm (blue) lens produce. It also shows how those three frames appear when magnified to the same size (i.e. the sensor size). The 800mm frame has a 1:4 size ratio relative to the 400mm frame which, for the purposes of this debate, has a 1:1 size ratio. You can clearly see that the prairie dog is much more than twice as large in the frame in the magnified 800mm image...it is four times as large. To put it in different terms, the prairie dog is about 25% of the frame in the 400mm image, but it is 100% of the frame in the 800mm image. A factor of four difference.

The second diagram demonstrates the one dimensional linear relationship between lens focal lengths. The 400mm and 800mm lenses have a 1:2 ratio relationship, since a 400mm diagonal AoV is 6°11', where as an 800mm diagonal AoV is 3°05'.

The third diagram plainly lays out WHY an 800mm lens enlarges the subject four fold: You can fit four 800mm frames into a single 400mm frame!! Full-frame scaling is two dimensional, not one dimensional like angle of view. You have to account for both dimensions when determining the difference in total detail on your subject. An 800mm lens may only have 1/2 the AoV, but it resolves 4x as much detail.

If this doesn't clear the problem up for you, then nothing will. This is about as plain and obvious as I can possibly make it. This is very basic, high school level geometry. It should be very obvious.

1181
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 11:17:30 AM »
This also causes a drastic loss of battery life ...

Which is solved by bigger batteries ... which is why I keep shouting for people to stop harping on "the small size of mirrorless" as a feature. Make a mirrorless camera as big as 5DIII and cram the sucker full of batteries.

... and the resulting information overload is distracting.  I turn it all of in my EVF cameras ...

For some. But isn't it great that you can actually turn it off, huh?  ;)

... the EVF is lousy in every way compared to an OVF.

Depends. Definitely so in 2012; it became better in 2013; and next year it'll be even better. For comparison, I remember a time when we all felt that film was still soooo much superior to digital and "pros" wouldn't touch it for serious work. But look at where we are today. So please don't judge EVF's on how they are now, as the technology is constantly being improved.  :)

Well, as always, nothing is so simple.

First, when it comes to batteries, even if someone makes a "mirrorless" with the same body design as a 5D III, it wouldn't necessarily be so easy to just cram it all full of batteries. For one, batteries are where a significant part of camera weight comes from. For the people who care MOST about camera footprint, size and weight are the two things they really only care about. In which case, they honestly don't care that an ultra tiny mirrorless camera that can barely be controlled with one hand, let alone two hands, has a microscopic battery with a microscopic battery life.

Batteries are also one of those areas of manufacturing that governments just love to regulate. Batteries utilize a number of relatively toxic chemicals and highly reactive metals. Environmentalists hate batteries, so governments regulate the crap out of batteries. The 5D II and 7D batteries were great, there was nothing wrong with them, however the 5D III had to be released along with a new battery type because of Japanese regulations. It's still compatible with the old ones, but in Japan, you have to use the new ones. Same deal with the 1D X, it's battery had to be completely redesigned to conform to Japanese and EU regulations. Stuffing some super large battery into a 5D III sized mirrorless would be fraught with regulatory issues...so it is probably far from as easy as it *sounds*.

When it comes to EVFs, in most respects even with the newest and greatest versions from 2013, they are woefully inadequate to those of us who NEED what OVFs offer...unlimited dynamic range, higher resolution than even the best theoretically possible with an EVF (@1" eye relief), 100% realtime behavior (i.e. the motion of subjects is replicated in real time by the OPTICAL viewfinder system), and are already capable of offering a considerable amount of functionality in a HUD-style display via the kind of transmissive LCD technology Canon uses in their current OVFs. Tricks like focus peaking, live hud histogram, face identification blinking, and a whole host of other features could actually be implemented in an OVF with a transmissive LCD. You do not actually HAVE to switch to an EVF in order to do these things. All you really need is a high resolution RGB metering sensor (something like what the 1D X has), and you would have all the information you needed to render all sorts of information onto an OVF Trans LCD real-time, superimposed over a REAL image that is not limited by the dynamic range of the sensor or EVF screen.

Canon has hinted at a Hybrid VF. I'm honestly curious to see what that is. I am hoping it is something like I've described above, because IMO that would be the best of both worlds. Even the BEST of EVFs from last year fall far short of what is necessary on the DR and resolution fronts. Dynamic range is doubly limited...first it is limited by the sensor, and second it is limited by the design of the EVF screen itself. Resolution in EVFs needs to be over 5000ppi in order for pixels to be invisible to the human eye at 1.25" eye relief for 20/20 vision. It needs to be over 12,000ppi in order for pixels to be invisible to the human eye at 1" eye relief for 20/10 vision. However, 12,000ppi is likely impossible, as the pixels would have to be so small, you would be filtering out red light...you would basically have a blue/green screen. EVFs have a very long way to go before they compare to OVFs, especially if OVFs eventually get more embedded HUD technology in their Transmissive LCD layers (at which point, I honestly do not think an EVF could EVER compare to a TLCD OVF).

1182
EOS Bodies / Re: What's Next from Canon?
« on: February 15, 2014, 12:02:35 AM »
I'm curious if the successor to the SX-50 will have dual-pixel technologies and what the zoom will be.

Very unlikely.  The pixels are too small to be divided in half, at least by Canon with their current fabrication technologies.

Canon's fabrication tech is only limited (supposedly, we don't really know this for sure) in the fabs for APS-C and FF. Canon already moved to 180nm fabrication several years ago for their small form factor sensors. The SX-50's sensor is 1/2.3", so it would be manufactured by their newer fabs. I'd be surprised if Canon wasn't using a smaller fabrication process than even 180nm for these sensors, honestly, but there isn't much information in the sensor world on Canon's fabrication tech (at least, they certainly don't seem to headline nearly as much as the other major players in the smartphone and video market sectors.)

1183
Lenses / Re: DxO & MTF Charts ... a little help please!
« on: February 14, 2014, 08:11:06 PM »
I read the Sony document. It is not a highly detailed technical paper but a summary of sorts. I found some useful info in the article. What I learned is that when interpreting an mtf chart the relative closeness of a dashed and solid line pair will generally indicate the quality of the defocused areas. That is to say if the dashed and dotted lines of the line pairs are close together or superimposed then that indicates the lens will have good bokeh. I didn't know that was something that could be measured but I guess it can. Maybe its not all telling but apparently a good indicator?

Aye, what Sony says is true. When the lines are on top of each other, you generally have very flat out of focus blur circles. They tend to be uniform from the center of the circle to the edge of the circle. When there is divergence, any number of alternate forms of blur circles can arise. Some even divergence and a relatively even falloff actually means the lens still has some spherical aberration, which usually results in good boke as well. When the meridional lines are all squirrely, then your boke will usually be pretty nasty.

1184
Have you the Tammy? Can you contribute for anything here at all?

You said it. You don't own it, and you've rejected the postings that are contrary to your opinions from owners of the lens.

In the case of the 1D X, you have 6.95µm pixels, or an area of 6.95^2µm: 48.3µm^2. The 7D has 4.3µm pixels, or an area of 4.3^2µm: 18.49µm^2. Again, because were working in two dimensions here, it's not a linear scale, you can fit 48.3/18.5 7D pixels into one 1D X pixel. That comes out to 2.61x 7D pixels per 1D X pixel. You would need a 2.6x TC in in order to completely normalize the crop difference between the 7D and 1D X, all else being equal.

Wouldn't that be a sqrt(2.6)x teleconverter? Every teleconverter I've seen lists their focal length multiplier, meaning a 2x teleconverter puts 4x the pixels on a target.

You are correct. That should actually read:

"That comes out to 2.61x 7D pixels per 1D X pixel. You would need a 1.6x TC in in order to completely normalize the crop difference between the 7D and 1D X, all else being equal."
Nice. I see you change your mind. You now admit to not have use a 2.6x tc to compensate, as you said before,, but a 1.6x.
If I have a 1dx and want the same pixels on the subject as the 7d, I have two choices. Put a 1,6x TC on the lens or upscale the image by 1.6x. When talk about upscaling you always talk about upscaling in both direction. Everything is upscaled 1.6x. Ok? Same with lenses. If I want a 400mm to act as a 600mm I put a 1.5x TC on it. Normally an upscaled image will not be as good as putting a tc on, or having a longer FL. But sometimes it does. And that not a claim for me that I can upscale the C400mm to give same IQ as the soft tammy @6.3. Its a question and a guess..Thats it!.
And now I'm out. 
Thanks!

First off, my bad. It was a typo. Not a change of mind. But still, my bad.

Second, your still not understanding. Things are magnified 2.61x. The LENS FOCAL LENGTH, and ONLY the lens focal length, is scaled by 1.6! It's the same deal in the end. If you square 1.615 (the actual focal ratio), what do you get? 2.61! The 7D resolves 2.61x more detail than the 1D X. To compensate for that difference, you need a focal length 1.6x as long. A 646mm lens results in 2.61x more 1D X pixels falling on the same subject area as a 400mm lens on the 7D. Don't get too caught up on the simple and scalar ratio of focal lengths...that doesn't tell you enough about the actual differences involved.

The difference in focal length is linear (1.615x), the difference in magnification is squared (2.61x). The value that really matters, from a detail perspective, is the magnification factor. If you use a 400mm lens on both a 1D X and a 7D, the 7D will resolve 2.61x MORE DETAIL. It sounds like a lot. It really IS a lot!

If you still don't believe me, maybe you will believe a well-known professional in the field of bird photography:

Size Does Matter; The Power of the Square of the Focal Length

Quote from: Art Morris
"In the original “The Art of Bird Photography” I wrote something to this effect: the size of the bird in the frame is not a factor of the focal length but rather a factor of the square of the focal length. In other words, if you go from a 400mm lens to an 800 mm lens, the bird will be four times bigger in the frame (not twice as big). "

The focal ratio between 800mm and 400mm is 2x, but the subject is enlarged in the frame by 4x! Subject size in the frame is related to the SQUARE of the Focal Ratio, it is not a linear relationship. You can clearly see that in Art's animated image of the bird...one was taken at 700mm, the other at 1120mm. The square of that ratio, 1120/700^2 or 1.6^2 is, yup, you've got it, 2.6x! The animated bird jumped in size in the frame by 2.6x, not by 1.6x. You can even download the animated image and do some area measurements yourself if you want. Draw a box around the bird when it's smaller, draw a box around the bird when it's larger, and compare the areas.

1185
Lenses / Re: DxO ... a little help please!
« on: February 14, 2014, 12:18:44 PM »
Another point on MTF charts - you don't want to compare a super telephoto to a wide angle lens - as you can see the IQ looks insanely higher on the former, but it's not really that way.  You should compare similar focal lengths to each other if using MTF charts, i.e 24mm prime to a 24-70 lens at the wide end.

Oh, the telephoto focal lengths are indeed that good. Thats WHY I invested $12,000 in the 600mm f/4 L II! You have no idea how much better it is. And that conforms with the theory. At 600mm, the vast majority of incident light is collimated. There isn't much bending going on. Not nearly as much as at 70mm or 24mm. An MTF is an MTF. There are no special considerations for focal length. You can compare any MTF chart to any other. They are about as honest a review of lens quality at any given focal length as you can hope for.
jrista, this is something I had read from Canon (will have to look for it), and I guess I didn't phrase it correctly.  It's not to say that the MTF charts lie, just that wide angle lenses may look really soft in comparison to telephoto charts, but that doesn't mean that they are as soft as they appear, and the value of MTFs is better used to compare similar focal lengths to each other.

I see what you are saying. Indeed, a wider angle lens is compressing a very wide field of view into the same physical region of the sensor. That compression certainly mitigates the impact of higher angle light being bent into the lens. The MTF charts really don't lie, though, and they are a normalized plot, so they tell you the same thing about lenses regardless of focal length. The illusion would be when you think your ultra wide angle lens performs as well as a telephoto "for what it is"...simple fact of the matter is, quite often, they really don't! I have the 16-35 and the 600mm, two of Canon's most extreme lenses. The corner performance of the 16-35 is well and truly ATROCIOUS. Even its center performance isn't all that great on a camera like the 7D (with small pixels/high resolving power.) This is clearly indicated by the MTF:




At the wide end, sagittal performance drops to 0.3!! Meridional performance drops to almost zero!!! Even at the long end, resolution suffers considerably in the corners.

My 600mm lens, on the other hand, produces what I consider perfection from center to corner. Both lenses live up to their MTFs. Even though you don't necessarily "feel" as though the 16-35mm lens is all that bad, all it takes is a little bit of investigation of the corners to see the MTF doesn't lie. Corner performance on the 16-35 is about as bad as it gets. (Canon REALLY needs to update that lens.)

That makes me think of another great resource (even if it's not as current as the edition CPS members receive when they join) for learning about all of this stuff - Canon Lens Work.  You can download the 11 PDFs free from Canon's European CPS website:
http://www.canon-europe.com/Support/Documents/digital_slr_educational_tools/en/ef_lens_work_iii_en.asp

The 10th PDF, OPTICAL TERMINOLOGY & MTF CHARACTERISTICS, has tons of great information on optics and MTF charts.  It's not light reading, but it will tell you everything you wanted to know and probably a whole lot more!

Aye! I read all the EF Lens Work documents years ago. Excellent, if complicated, stuff.

One of the best explanations I've seen on how to read MTF charts is on page 14 of Sony's Alpha lens brochure which also contains great diagrams and explanations of all core lens concepts:
www.docs.sony.com/release/Alpha_Lens_Brochure_Fall_2012.pdf

I've never looked into Sony's documents. I'll have to check it out.

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