Patent: Canon 100-400mm f/5.6-7.1

[AlanF]

I see no reason it wouldn’t as the current EF lenses work flawlessly with my much maligned R.

You missed my posts with slcick. The current 100-400mm works very well on the R and RP. But, for birds in flight, the lens on the R is not the best for the more difficult shots. If a new RF 100-500mm on a newer R series is good for BIF, I’ll get both. If not, I’ll stick to my DSLRs until Canon produces what I want.

 

[scyrene]

Sorry but 7.1 is too damn slow. Physics is a bitch and all that especially in lower light - I'm no Tool (who according to some turned his family into bokeh) but I do like to have SOME background seperation and not run larger ISO numbers. f5.6 is a compromise of size and speed I'm okay with) - 7.1? Just absolutely 100% no

Here's an old shot with good background separation. What aperture do you think I used? Hint: it's narrower than f/7.1*. A lot of other factors are at play - subject distance, background distance, field of view, etc.



*It's f/10, and ISO 1250, taken in woodland - so let's get some perspective please!.

 

[Kit.]

Here's an old shot with good background separation. What aperture do you think I used?

The lens entrance pupil (in diameter) is about 3 times as large as the bird's eye. Good enough for subjects with such small eyes.

 

[AlanF]

Here's an old shot with good background separation. What aperture do you think I used? Hint: it's narrower than f/7.1*. A lot of other factors are at play - subject distance, background distance, field of view, etc.

View attachment 188877

*It's f/10, and ISO 1250, taken in woodland - so let's get some perspective please!.

Beautiful shot! I like the nature of the blurred background as well. There is a nice texture about it that gives the feel that the bird is in woodland but without it being intrusive.

 

[Bert63]

I'll keep my current 100-400ii, no reason to replace it, should work great on the R5

Me as well. Nothing to look forward to in the 100-500L from where I'm sitting.

 

[Bert63]

Here's an old shot with good background separation. What aperture do you think I used? Hint: it's narrower than f/7.1*. A lot of other factors are at play - subject distance, background distance, field of view, etc.

View attachment 188877

*It's f/10, and ISO 1250, taken in woodland - so let's get some perspective please!.

Focal length? Did I miss it somewhere?

 

[scyrene]

Beautiful shot! I like the nature of the blurred background as well. There is a nice texture about it that gives the feel that the bird is in woodland but without it being intrusive.

Thanks very much! As is often the case, I got lucky

 

[scyrene]

Focal length? Did I miss it somewhere?

The FL is 1000mm, so a fair bit longer than what we're talking about in the lens this thread is about, but it's rather beside the point I'm trying to make - people are dismissing f/7.1 out of hand, whereas I contend a lot of other factors are important, too. You can get good long lens shots at narrower apertures, under some circumtances, contrary to the naysayers. I'd expect a lens like this to have a much closer MFD than my 500L, which would help, and it's on a crop sensor, which will make a difference, too.

 

[tron]

The FL is 1000mm, so a fair bit longer than what we're talking about in the lens this thread is about, but it's rather beside the point I'm trying to make - people are dismissing f/7.1 out of hand, whereas I contend a lot of other factors are important, too. You can get good long lens shots at narrower apertures, under some circumtances, contrary to the naysayers. I'd expect a lens like this to have a much closer MFD than my 500L, which would help, and it's on a crop sensor, which will make a difference, too.

I am sorry FLand aperture used are not beside the point.

Having a 500mm f/4 you had the luxury of 1000mm f/8 or f/10 so closing by 2/3 of a stop at your case. Would you have the sam e luxury with f/7.1 which would make it f/14 and f/16 if you close by 2/3 of a stop?

ISO would become 2000.
7.1 would up to the DLA limit of a future R at 45Mpixels so f/10 is OK I guess but f/16?

I am sure it would make a wonderful portable lens of course. This portability would make it successful depending of course on IQ and fast focusing capability.

Let's wait until it is out.

 

[scyrene]

I am sorry FLand aperture used are not beside the point.

Having a 500mm f/4 you had the luxury of 1000mm f/8 or f/10 so closing by 2/3 of a stop at your case. Would you have the sam e luxury with f/7.1 which would make it f/14 and f/16 if you close by 2/3 of a stop?

ISO would become 2000.
7.1 would up to the DLA limit of a future R at 45Mpixels so f/10 is OK I guess but f/16?

I am sure it would make a wonderful portable lens of course. This portability would make it successful depending of course on IQ and fast focusing capability.

Let's wait until it is out.

You're missing my point so I will reiterate as clearly as I know how.

So on all these threads about -f7.1 zoom a number of people have said it's unusable. That is, f/7.1 is an unusable aperture (in the case of this patent and the recently-announced -500mm f/7.1 zoom) for long lens work, birds in forests, etc. These have been blanket statements about aperture, without regard to focal length.

I don't have a photograph to hand taken at 500mm f/7.1 - I could take one with the bare 500L. But I don't need to do that to make my point (which I have repeated on a number of threads), which is that I have done a tonne of bird photography at f/10 and it's been fine - not too dark most of the time, and the backgrounds are adequately blurred.

Obviously using a zoom with a maximum aperture at the long end of f/7.1 is not precisely the same as using a 500mm + 2x TC stopped down a little. Obviously I have more reach*. But that is not the point being made here. One last time: f/7.1 is perfectly usable for bird photography (and many other types), sometimes even in low light.

DLA is irrelevant to this discussion, but since you brought it up, the photograph I posted above was taken on a 5Ds, which has even smaller pixels than the rumoured R5. Unless you are cropping more heavily on a higher res sensor, diffraction is no more apparent regardless of resolution.

*as an aside, a shorter FL can produce equally- or even more blurred backgrounds if the MFD is shorter, and I'd expect these zoom lenses to focus closer than the supertelephoto primes.

 

[SecureGSM]

The FL is 1000mm, so a fair bit longer than what we're talking about in the lens this thread is about, but it's rather beside the point I'm trying to make - people are dismissing f/7.1 out of hand, whereas I contend a lot of other factors are important, too. You can get good long lens shots at narrower apertures, under some circumtances, contrary to the naysayers. I'd expect a lens like this to have a much closer MFD than my 500L, which would help, and it's on a crop sensor, which will make a difference, too.

here is Sigma 100 400 5 -6.3 at 400/F6.3.. 500 at F7.1 should give a similar look. see if you like it:

https://www.birdforum.net/attachment.php?s=77b46e017ca26dc86cbab8030cddd870&attachmentid=645140&d=1509699325

https://www.birdforum.net/attachment.php?s=77b46e017ca26dc86cbab8030cddd870&attachmentid=645153&d=1509699728

and here is more for your judgement:

Sigma 100-400 f/5.0-6.3

New leaks suggest there will soon be an announcement of a Sigma 100-400mm f/5.0-6.3 https://petapixel.com/2017/02/20/photos-4-new-sigma-lenses-leaked-3-new-art-lenses-coming-soon/ The fact it's 6.3 at the long end places it below the usual 100-400 options in terms of size and weight, as does...

www.birdforum.net

 

[AlanF]

The FL is 1000mm, so a fair bit longer than what we're talking about in the lens this thread is about, but it's rather beside the point I'm trying to make - people are dismissing f/7.1 out of hand, whereas I contend a lot of other factors are important, too. You can get good long lens shots at narrower apertures, under some circumtances, contrary to the naysayers. I'd expect a lens like this to have a much closer MFD than my 500L, which would help, and it's on a crop sensor, which will make a difference, too.

Doubling the focal length does make a lot of difference to the depth of field. I am no expert in this area and may have it wrong. But, my understanding is the depth of field, all else being equal, increases linearly with f-number but decreases inversely with the focal length squared. So, if you double the focal length of the lens, the dof decreases by a factor of 4. Shooting a 1000mm lens at f/10 gives the same depth of field and subject separation as shooting a 500mm lens at f/2.5. Similarly, shooting a 400mm at f/5.6 gives the same depth of field as shooting a 500mm lens at f/8.75. But, it gets more complicated if you crop the shorter focal length image and view at the same size as for the longer. I think you then have to divide the dof by the crop factor. So, after cropping, the 1000mm lens at f/10 will give the dof of the 500mm shot at f/5. And the 500mm at f/7.1 will give the very close to the same dof and subject separation as a 400mm at f/5.6.

Take home message is that the 500mm/7.1 gives us croppers the same subject separation from background as a 400/5.6. Please correct me if I am wrong.

Edit SecureGSM posted just as I was posting and so it seems my maths is correct.

 

[scyrene]

Doubling the focal length does make a lot of difference to the depth of field. I am no expert in this area and may have it wrong. But, my understanding is the depth of field, all else being equal, increases linearly with f-number but decreases inversely with the focal length squared. So, if you double the focal length of the lens, the dof decreases by a factor of 4. Shooting a 1000mm lens at f/10 gives the same depth of field and subject separation as shooting a 500mm lens at f/2.5. Similarly, shooting a 400mm at f/5.6 gives the same depth of field as shooting a 500mm lens at f/8.75. But, it gets more complicated if you crop the shorter focal length image and view at the same size as for the longer. I think you then have to divide the dof by the crop factor. So, after cropping, the 1000mm lens at f/10 will give the dof of the 500mm shot at f/5. And the 500mm at f/7.1 will give the very close to the same dof and subject separation as a 400mm at f/5.6.

Take home message is that the 500mm/7.1 gives us croppers the same subject separation from background as a 400/5.6. Please correct me if I am wrong.

Edit SecureGSM posted just as I was posting and so it seems my maths is correct.

I wasn't saying the results would be precisely the same. I knowingly didn't post a shot with precisely the same specs as this thread, or the other thread's lenses. My point is that you can get good subject separation at f/7.1. I said 'subject and background distance are important too'. And of course FL matters, as does sensor size. But these are all beside the point I was trying to make. But I should know better on here.

I'll just repeat one last time: people who claim f/7.1 is unusable are wrong. That's it! That's the only point I was making.

 

[tron]

You're missing my point so I will reiterate as clearly as I know how.

So on all these threads about -f7.1 zoom a number of people have said it's unusable. That is, f/7.1 is an unusable aperture (in the case of this patent and the recently-announced -500mm f/7.1 zoom) for long lens work, birds in forests, etc. These have been blanket statements about aperture, without regard to focal length.

I don't have a photograph to hand taken at 500mm f/7.1 - I could take one with the bare 500L. But I don't need to do that to make my point (which I have repeated on a number of threads), which is that I have done a tonne of bird photography at f/10 and it's been fine - not too dark most of the time, and the backgrounds are adequately blurred.

Obviously using a zoom with a maximum aperture at the long end of f/7.1 is not precisely the same as using a 500mm + 2x TC stopped down a little. Obviously I have more reach*. But that is not the point being made here. One last time: f/7.1 is perfectly usable for bird photography (and many other types), sometimes even in low light.

DLA is irrelevant to this discussion, but since you brought it up, the photograph I posted above was taken on a 5Ds, which has even smaller pixels than the rumoured R5. Unless you are cropping more heavily on a higher res sensor, diffraction is no more apparent regardless of resolution.

*as an aside, a shorter FL can produce equally- or even more blurred backgrounds if the MFD is shorter, and I'd expect these zoom lenses to focus closer than the supertelephoto primes.

I do not disagree about the use of f/7.1 but about maximum use which includes teleconverters!

I have also used 5DsR + 500 + 2XIII successfully and I was very happy with the result.

It is just that you cannot achieve the same max results if needed.

And I cannot stress enough the portability of the 100-500.

 

[AlanF]

I wasn't saying the results would be precisely the same. I knowingly didn't post a shot with precisely the same specs as this thread, or the other thread's lenses. My point is that you can get good subject separation at f/7.1. I said 'subject and background distance are important too'. And of course FL matters, as does sensor size. But these are all beside the point I was trying to make. But I should know better on here.

I'll just repeat one last time: people who claim f/7.1 is unusable are wrong. That's it! That's the only point I was making.

My comments were meant to support what you wrote and that I agreed with you!

 

[scyrene]

I do not disagree about the use of f/7.1 but about maximum use which includes teleconverters!

I have also used 5DsR + 500 + 2XIII successfully and I was very happy with the result.

It is just that you cannot achieve the same max results if needed.

And I cannot stress enough the portability of the 100-500.

Oh well, I'd absolutely agree that use of teleconverters on a lens that's already f/7.1 to begin with will cause issues, though I would add on a 1.4x with no worries, on a modern mirrorless body that can still AF with that. I used to stack teleconverters and shoot birds at f/14, and sometimes the extra reach was enough to justify (to my satisfaction at least) the loss of sharpness. No AF though!

 

[scyrene]

My comments were meant to support what you wrote and that I agreed with you!

Oh, sorry. Thanks! I'm grumpy today

 

[AlanF]

Oh, sorry. Thanks! I'm grumpy today

I am very grateful to your post because it got me thinking more deeply about dof and focal length and aperture. And I now understand more than I did.

 

[SecureGSM]

Doubling the focal length does make a lot of difference to the depth of field. I am no expert in this area and may have it wrong. But, my understanding is the depth of field, all else being equal, increases linearly with f-number but decreases inversely with the focal length squared. So, if you double the focal length of the lens, the dof decreases by a factor of 4. Shooting a 1000mm lens at f/10 gives the same depth of field and subject separation as shooting a 500mm lens at f/2.5. Similarly, shooting a 400mm at f/5.6 gives the same depth of field as shooting a 500mm lens at f/8.75. But, it gets more complicated if you crop the shorter focal length image and view at the same size as for the longer. I think you then have to divide the dof by the crop factor. So, after cropping, the 1000mm lens at f/10 will give the dof of the 500mm shot at f/5. And the 500mm at f/7.1 will give the very close to the same dof and subject separation as a 400mm at f/5.6.

Take home message is that the 500mm/7.1 gives us croppers the same subject separation from background as a 400/5.6. Please correct me if I am wrong.

Edit SecureGSM posted just as I was posting and so it seems my maths is correct.

Measuring 25, 50, 100 meters to subject.
DOF of 500 at F7.1 is equivalent to DOF of 400 at F4.6 approx. or 300 at F2.6

Meaning that at the 500mm Bokeh should be more pronounced than 400/5.6 but at 400 mm lens bokeh will be harsher being F6.3 vs F5.6 of the EF 100-400.

However, if I was reach limited .... 600mm end of Sigma 100-600/6.3C at F6.3 is equivalent to 500 at F3.7 , 400 at F2.3 and 300 F1.35

Go Sigma ?

Cheap 600/6.3 DOF is shallower that 500/4 DOF

 

[AlanF]

Measuring 25, 50, 100 meters to subject.
DOF of 500 at F7.1 is equivalent to DOF of 400 at F4.6 approx. or 300 at F2.6

Meaning that at the 500mm Bokeh should be more pronounced than 400/5.6 but at 400 mm lens bokeh will be harsher being F6.3 vs F5.6 of the EF 100-400.

However, if I was reach limited .... 600mm end of Sigma 100-600/6.3C at F6.3 is equivalent to 500 at F3.7 , 400 at F2.3 and 300 F1.35

Go Sigma ?

Cheap 600/6.3 DOF is shallower that 500/4 DOF

The dof calculator gives the dof of the whole field of view, when viewed at a particular distance, defined by the circle of confusion for the image. When you crop out some of the image taken by two lenses of different focal lengths, say of a bird in a bush, and view at the same output size, the relative depths of field change because the smaller image is enlarged more. For a 500mm lens vs 600mm lens, the dof of the smaller lens is reduced by a relative factor of 1.2x. The cropped image image from 600mm f/6.3 will have the same dof as the same view crop from a 500mm lens at f/5.25.