Patent: Canon RF 70-400mm f/4.5-5.6L IS USM and more

Sep 17, 2014
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I am not splitting hairs, just exploding the myth about the extra reach of APS-C and M4/3 when you don’t take into account pixel density. You have now changed tack by talking about field of view, which is not what you meant in your previous posts. The narrower field of view is in fact a disadvantage, not an advantage, when you are doing bird and nature still photography - it’s more difficult to find your subject and when it gets closer it can overfill the frame. Video is a different matter of course. Canon changed the game when it brought in the 5DS several years ago and there is now the new world of high density FF sensors. And Nikon did it’s bit earlier with the 800+ series and now Sony.

Yes, i know about pixel density, im not a beginner.
How many FF cameras are out there with the same pixel density or a 20 MP apsc? One?
And how many can have the same speed of a 7D dor example? Zero? I am talking about Canon land.

Let's not talk about price.
The Sony A74 is better option than apsc because of wider focal length BUT that price is very different. Thats why i mentioned 6xxx series in the first post. I you don't have 4000 dollars for a body then apsc still offers better reach.
 
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AlanF

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Yes, i know about pixel density, im not a beginner.
How many FF cameras are out there with the same pixel density or a 20 MP apsc? One?
And how many can have the same speed of a 7D dor example? Zero? I am talking about Canon land.

Let's not talk about price.
The Sony A74 is better option than apsc because of wider focal length BUT that price is very different. Thats why i mentioned 6xxx series in the first post. I you don't have 4000 dollars for a body then apsc still offers better reach.
Lot's of beginners do use forums like ours for advice, and we owe it to them to explode myths and not let them be at the mercy of salesmen etc who try to sell them M4/3 etc etc on the pretence of greater reach. The facts are that all three major makers now provide the same or similar resolution FF as APS-C. The speed and price are irrelevant to the basic fact that a 200-600mm is not simply equivalent to a 320-840mm in terms of reach because pixel density has to be taken into account and price and speed are different considerations that do not affect the argument about reach.
 
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What Alan just said. not the same. Same angle of view but lens compression and bokeh would be distinctively different.
What you just said, except there’s no such thing as ‘lens compression’. Differences in perspective are entirely due to the camera-to-subject distance (which is explained and demonstrated in the article you link, after the author’s false start of saying it’s a function of distance and focal length).
 
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SteveC

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What you just said, except there’s no such thing as ‘lens compression’. Differences in perspective are entirely due to the camera-to-subject distance (which is explained and demonstrated in the article you link, after the author’s false start of saying it’s a function of distance and focal length).

Ah, someone finally brings up perspective.

No matter how much you shrink the sensor, you're not getting the effect of standing at a greater distance and zooming in more (which would actually cause the subject to obscure less of the background, among other things). You're just cropping the picture before you take it. Now it may have differences in quality because the sensor has different-sized pixels, but if you account for that, all crop factor gives you is--crop.

Or to put it another way, if all you had to do to make a lens "longer" was to make the sensor smaller...why not just put a micro-dot of a sensor in that is three pixels wide by two tall? Your long lens magically becomes a lens that's on the order of 1,000,000 mm or about a kilometer. But--let's face it--a 6P picture wouldn't do much for anyone (though it might end up hanging in a modern art gallery). This is why I really don't like it when retailers give the crop-factor "corrected" focal length as if it were more meaningful than the true one.
 
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riker

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This is clearly a next generation 100-400 with the extra 30mm thanks to the RF mount. If they even make it smaller/lighter than the current 100-400, it might be enough reason for me to switch to RF.
Although I would love to see an RF 100-300/4 with less weight/size than the current 100-400.
The thing is I LOVE what the 100-400 is capable of but I HATE to carry it while travelling. It's killing me. I need something in the 200-400 range which is at least 300-500g less.
 
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SteveC

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This is clearly a next generation 100-400 with the extra 30mm thanks to the RF mount. If they even make it smaller/lighter than the current 100-400, it might be enough reason for me to switch to RF.
Although I would love to see an RF 100-300/4 with less weight/size than the current 100-400.
The thing is I LOVE what the 100-400 is capable of but I HATE to carry it while travelling. It's killing me. I need something in the 200-400 range which is at least 300-500g less.

I have imagined myself a couple of years down the road with some sort of RF-mount body but also getting that 100-400 EF (which I don't have yet) and using an adapter. This might make the second half of that vision silly--unless I want to use that 100-400 EF on an M body as well.
 
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AlanF

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This is clearly a next generation 100-400 with the extra 30mm thanks to the RF mount. If they even make it smaller/lighter than the current 100-400, it might be enough reason for me to switch to RF.
Although I would love to see an RF 100-300/4 with less weight/size than the current 100-400.
The thing is I LOVE what the 100-400 is capable of but I HATE to carry it while travelling. It's killing me. I need something in the 200-400 range which is at least 300-500g less.
You would probably have to have an f/6.3 if you want it that much lighter. The Tamron 100-400mm nearly got there but for me wasn't fast focussing enough, had poorer IS and was weaker at the edges compared with Canon, but otherwise not bad. I could live with an f/6.3 if it had Canon AF, IS and optics.
 
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SecureGSM

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What you just said, except there’s no such thing as ‘lens compression’. Differences in perspective are entirely due to the camera-to-subject distance (which is explained and demonstrated in the article you link, after the author’s false start of saying it’s a function of distance and focal length).
Well, here is an example that demonstrates how various focal lengths affect perspective compression “fenomena” :)



1569167698831.jpeg
 
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SteveC

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Well, here is an example that demonstrates how various focal lengths affect perspective compression “fenomena” :)



View attachment 186728
Yes, it demonstrates that changing the distance affects perspective. The fact that focal length is also being changed is irrelevant, but it appears the author doesn’t fully understand that fact.

Here’s the proper demonstration, with details in the quoted text below (essentially, left side varies only focal length, right side varies distance and focal length, it’s obvious which one determines perspective):

index.php


Here's an example from the wiki page on perspective distortion, an example that illustrates some of this confusion:

220px-Focal_length.jpg


You see the different focal lengths printed on the images, and you see the relative sizes of the two water bottles changing, and you think that focal length is the reason. Even the text in the caption of that image suggests the effect is due to focal length. But consider...the pink bottle is the same height in all three images - therefore, as the focal length is reduced, the camera must have been moved closer to achieve the same framing. It's the movement of the camera, not the change in focal length, that results in the different perspectives.

Let me try to illustrate what I mean with a similar set of examples, but where I first vary just focal length but not distance, and then vary focal length and distance. Since I prefer beverages other than water, I selected a different pair of subjects for a similar test.

View attachment 186204

The two bottles are 18" apart, and the distances in the image above are measured from the sensor to the front bottle. All were shot at f/5.6. As described above, it's normal for the bottle in front to look larger, that's perspective - objects that are further away look smaller, even though we know they are the same size. Note that the bottle in front is the same height in all the images.

In the left column, the 50mm and 24mm shots were at the same distance as the 100mm images, and the images were cropped to match the framing of the 100mm image. As you can see, the relative size of the rear bottle is the same in all the images. The perspective is the same - the two bottles maintain the same relative size, despite the differing focal lengths. The distance is the same, so the perspective is the same.

In the right column, which is equivalent to the water bottle shots from the wiki page, the 50mm and 24mm shots were taken at successively closer distances to the bottles, matching the framing to the 100mm shot by moving the camera. As you can see, the relative size of the rear bottle gets smaller as the camera is moved closer. Different perspective, because the distance is changing. Comparing the side-by-side 50mm and 24mm images, you can see that with the same focal length but different subject distances, the perspective is different.

So, varying focal length alone, without changing distance, does not affect perspective. As stated above (by me and others), perspective is determined by distance, and distance alone.

As others pointed out above, 'telephoto' compression and 'wide angle' expansion distortion are the same phenomenon. The reference to 'telephoto' and 'wide angle' there is misleading - it has nothing to do with the focal lengths, only the distance. But longer lenses are usually used at longer distances, and wide lenses are usually used at closer distances (think of framing a person for a portrait), thus the erroneous association with a lens type when it's really the commonly used distances for those lenses that is the cause of both types of perspective distortion.

Regardless of whether or not this clarifies what determines perspective, I'm about to enjoy that bottle of Chocolate Stout. ;D
 
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jhpeterson

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Of course what I really want is the 200-400 with the built-in 1.4, but it is not currently a realistic option for me when it comes to budget, size, and baggage allowance.
What I really want is a 70-280 and f:2.8 across the full range with a 1.4x built in. It would likely be 2-4 cm shorter than the 200-400, although as large around. Since it should take up less length, I'd expect it to be slightly lighter and as for price, I can only hope it comes in less. On the other hand, I'm sure it would be more than the 70-200 and 100-400 added together.
 
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Why are you thinking the price will be higher? I agree it could be but not necessarily a given from my perspective. I grant some of the early lineup (e.g., 50/1.2) were hugely more expensive but they're clearly a quantuum leap in IQ. The 24-105/4IS seems to be 126,000 yen for the EF vs. 152,000 for the RF... hmm, 20% more expensive for comperable IQ but substantially smaller size. So when you say "considerably higher" you're thinking that they'll just be charging 20% more for RF? If so do you see that as marketing strategy, or development/manufacture costs? It might just be that they're charging more because it's relatively new, and also because sales are probably far lower than EF still so they have to amortize the R&D across a smaller number of units.

Those in the market for an EF 100-400 mk II can also find used models in good condition at a substantial discount. It will take several years for that to be the case for most of the RF lenses (besides the 24-105.)
 
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Optics Patent

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Those in the market for an EF 100-400 mk II can also find used models in good condition at a substantial discount. It will take several years for that to be the case for most of the RF lenses (besides the 24-105.)

Why is the 24-105 f4 so discounted? Was it oversold as a kit lens? I’m tempted and will do a compare with the 2.8 via CPS.
 
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Why is the 24-105 f4 so discounted? Was it oversold as a kit lens? I’m tempted and will do a compare with the 2.8 via CPS.

The RF 24-105 has been included with what is probably the majority of all EOS R and EOS RP cameras sold so far. I suspect that as people upgrade to the RF 24-70 2.8 or switch to the RF 24-240, they will likely try to unload their used 24-105s. They certainly seem to me to be the most widely available used RF lenses on the market. That wide availability both as new and used should help keep the price of that lens reasonable for the foreseeable future.
 
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SteveC

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The RF 24-105 has been included with what is probably the majority of all EOS R and EOS RP cameras sold so far. I suspect that as people upgrade to the RF 24-70 2.8 or switch to the RF 24-240, they will likely try to unload their used 24-105s. They certainly seem to me to be the most widely available used RF lenses on the market. That wide availability both as new and used should help keep the price of that lens reasonable for the foreseeable future.


If I recall correctly there's 24-105 L RF lens and a non-L one too.

Given how much actual distortion the 24-240 has, if I had a 24-105 L I'd be inclined to keep it.
 
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