Canon 7D plus Canon 400mm f5.6 versus Canon 7D plus 100-400mm

[Dan Brown]

A few questions regarding the Canon 7D plus Canon 400mm f5.6 non zoom. Is the straight 400mm sharper than the 100-400? Will it AF with a TC? Is it faster focusing? I am shooting Nikon currently but the 7D plus straight 400 f5.6 is intriguing as Nikon doesn't have a comparable combo (80-400mm zoom ain't so good!). Opinions appreciated.

[John Guastella]

The 7D is not capable of f/8 AF (at least not yet!), so it will not AF through the viewfinder with the Canon 400mm f/5.6 lens when a Canon extender is attached, unless one uses the tape-pinning trick. As I understand it, some of the 3rd party extenders will allow AF with the 7D - 400mm f/5.6 combo - can't comment on the IQ with those, never tried them.

As far as IQ is concerned, when I first began doing bird photography in 2009 and was triying to decide which lens to buy, I rented both the 400mm f/5.6 and the 100-400mm zoom. I found that the prime beat the zoom handily and bought the prime immediately. However, since the zoom I used was a rental, there is always the possibility that it wasn't functioning properly. Other Canon shooters seem to love the 100-400mm zoom, and it does have the advantage of having IS, which the prime lacks.

Even though my main lens is now the 500mm f/4, I still have the 400mm f/5.6. IMO, it's a marvelous little lens, light as a feather, and it punches way above it's weight (and price) with regard to IQ. I use it instead of the 500mm when I want to take a casual hike or just check out a new birding area. And for those BIF situations when the subjects are close and moving quickly (such as shooting the feeding Elegant Terns at Bolsa Chica in the summer), it is an excellent choice.

John

[Roger Clark]

Sharper? Just check Canon's MTF charts. Most important are the thin black lines (dotted and dashed): that represents the fine detail wide open.

100-400:
http://www.usa.canon.com/cusa/consum..._5_5_6l_is_usm

400:
http://www.usa.canon.com/cusa/consum...0mm_f_5_6l_usm

The spread between the solid and dashed lines are bad, and lower is worse. The 100-400 at 400 may be sharper in the center couple of mm of the focal plane, but worse further from the center.

Roger

[Daniel Cadieux]

The prime is a bit faster at AF, but the zoom is no slouch and I am happy anytime I get flight opportunities with it. The prime is sharper but you need to pixel-peep for that...something I never do as I do not look at my files that way or my prints with a magnifying glass, but the zoom is sharp as well and sharpens up just as nicely in post (you could never tell which lens took which photo if placed side-by-side if not magnified to 400%!!). The 100-400 has a 6 foot MFD compared to about 15 for the prime, I've been thankful for that very short distance on numerous occasions (around feeders, and for shorebirds that approach way close when lying prone in the mud, and for portraits of tame larger birds), and makes it a good "macro" lens for flowers and larger insects.

Both lenses are excellent, and I remember being in quite a predicament when it was time to choose which one to purchase. I would have been just as happy with either one.

[Roger Clark]

There is also another alternative: the 300 f/4 L IS with 1.4x TC. The minimum focus distance 4.9 feet (1.5 meters), so is closer than either the 100-400 ot 400 f/5.6. And the 300 has IS. My 300 +1.4x TC is sharper than my 100-400 at 400. The 300 f/4 is also smaller and lighter (2.62 pounds) than the 400 (2.75 pounds), or 100-400 (3.04 pounds).

The canon mtf chart for comparison is at: http://www.usa.canon.com/cusa/consum...mm_f_4l_is_usm

All three lenses, 100-400, 400, 300 are rumoured due for new and better models, but the rumours have been around for years. But with the new version II of many lenses out, maybe it will happen soon.

Roger

[Dan Brown]

There is also another alternative: the 300 f/4 L IS with 1.4x TC. The minimum focus distance 4.9 feet (1.5 meters), so is closer than either the 100-400 ot 400 f/5.6. And the 300 has IS. My 300 +1.4x TC is sharper than my 100-400 at 400. The 300 f/4 is also smaller and lighter (2.62 pounds) than the 400 (2.75 pounds), or 100-400 (3.04 pounds).

The canon mtf chart for comparison is at: http://www.usa.canon.com/cusa/consum...mm_f_4l_is_usm

All three lenses, 100-400, 400, 300 are rumoured due for new and better models, but the rumours have been around for years. But with the new version II of many lenses out, maybe it will happen soon.

Roger

A good option, Roger. I am assuming that the 300+1.4 AF's! Is the combo faster AF than the 100-400?

[John Guastella]

I am assuming that the 300+1.4 AF's!

The 300mm f/4 will have a maximum aperture of f/5.6 with the Canon 1.4X extender attached. So yes, the Canon 7D wil AF through the viewfinder with that combination. However, AF is slower than with the bare lens. More importantly, the IQ takes a hit, more so than with Canon's supertelephoto f/4 lenses.

But if you're considering a 300mm + extender, why wouldn't you just stick with Nikon's version of that combination (since you're currently a Nikon shooter)?

John

[Dan Brown]

Sounds like the -
7D with it's 8 fps rate, DX crop, 18 mpx and nice IQ..............$1500
with the 300 f4 with it's 4.9 mfd and IS...................................$1350
plus a 1.4 tc III allowing AF and equaling 420mm....................$420

makes a nice low cost rig for BIF!...........................................$3240

FYI, I did a quick Nikon Comparison below

D7000 with it's 6 fps rate, DX and nice IQ..............$1000
(or D300 plus battery pack for 9 fps and lower IQ + $500)
with the Nikon 300 f4 with it's 4.8 mfd (no VR).......$1370
plus a 1.4 tc II allowing AF and equaling 420mm......$500

Nikon version for low cost BIF rig...........................$2870 to $3370

LOOKS LIKE CANON HAS THE EDGE here with DX frame rate, IS and IQ for BIF

[nrohrbacker]

I have the 7d and had the 400/5.6, until I recently sold it. I rented them all before I got the 400. The 300 + TC I thought was too slow to focus with TC. The 100-400 that I got from lensrental.com did not even focus well. They were great, sent me a Brand New one next day air. This one was crap as well. That being said, I have seen great images with the 100-400 online, but I believe the design of this lens, or canon QC is not up to to snuff with respect to this lens. I have now moved on to much more expensive equipment. If I were you. Buy a used 7d and 400/5.6 for less than 2k and don't look back. Hone your skills and go from there. Good luck.

[arash_hazeghi]

Dan,

I don't think switching to Canon will solve your BIF problems. You will find that just like your Nikon setup, 400mm is too short for general BIF, you will have to crop a lot and IQ will be poor even if the lens is sharp. Plus your D800 AF which is a pro module is a lot better than the 7D for flight so it is likely that you will be disappointed.

Unless you plan carefully and go to places where birds are large, close, approachable or work on approach techniques-which you can do with your Nikon as well-I don't think you will be happy if your intention is to get high quality flight shots.

Hope this helps

Arash

[Jon Rista]

I have to agree with Arash here. A 400mm (or 420mm) lens is a bit on the short side for BIF. I currently use the 100-400mm with a 7D, and I've never been satisfied with my BIF photos @ 400mm. The birds, except in the case of fairly large ones like GBH or American White Pelican, rarely cover more than about 25% of the frame. I rented the Canon EF 300mm f/2.8 L II IS this summer, along with a 2x TC III. It took some practice and technique to keep birds in the frame, but BIF at 600mm f/5.6 produced much larger birds in frame that had a lot more detail. I think 500mm f/4 would be pretty ideal for BIF, and with a 1.4x TC would give you 700mm for extra reach in a pinch. A nice long lens is also great for getting nicely isolated shots of shore birds and the like at low angle from a much more comfortable distance than 400mm.

I actually think Nikon's 500mm f/4 lens, and possibly even their 300mm f/2.8 lens, are cheaper than the Canon counterparts (or at least the newer versions)...so switching brands probably wouldn't do you a lot of good. I'd stick with Nikon, and put your money into a solidly good telephoto lens.

[Roger Clark]

I'll agree with others that there would probably be little difference between the nikon and canon system listed, so it would probably not be worth changing.

I'll also agree that one often wants more reach. A 500 f/4 is certainly sweet. But let's get a little perspective. Not that long ago the top end pro setup was (in canon land) a 1D Mark III (7.2 micron pixels) and 500 f/4. But a 7D (4.3 micron pixels) with a 300 f/4 gets the same pixels on subject as a 1DIII with the 500, and about the same signal-to-noise ratio. So if one can't afford a 500 f/4, ro do not want to spend that much on a lens, something like the 300 f/4 is still a great setup.

Here is a BIF of a lilac breasted roller made with a 300 mm lens (no TCs):
http://www.birdphotographers.net/for...ller-in-Flight
Made from a safari vehicle (lots of restrictions in safari photography).

Roger

[Andre van As]

This thread has outlined my dilemma as I am thinking of moving into the DSLR arena with a 5DMk3 and a 100-400 lens supplemented by a 1.4 or 2X TC. Dan's comment about the AF being slower with the 100-400 compared with the 400 prime lens worried me somewhat. So is the AF speed driven by the lens or camera as my reading of the specs suggests that the new Mk3 has a fast autofocus rivaling the 1DX camera? In my film days I used a variety of Nikon bodies but always used a zoom lens for nature etc - the 70-200 or 200-600 - both of which I still have. I got very satisfactory results but never was able to go pixel hunting as per Dan C's comment above but got perfectly satisfactory prints with Cibachrome up to 12X16 inches. But the world has changed and I suspect that lens equipment is superior to the glass from the 1970's, all of this being driven by the demands of the digital medium. WRT telephoto it has been my experience in the past that you get better images from closer ranges using shorter lenses than with very long lenses at longer distances. Is this still the case?

I would love to hear your input on my comments

Regards

Andre

[Jon Rista]

Andre, I would strongly warn against using the 100-400mm lens with a TC. For one, using a 2x TC with that lens at 400mm means your maximum aperture drops to f/11. It is doubtful any Canon body would AF with that. The 100-400mm lens with a 1.4x TC is f/8, so only a 1D series body would officially AF with it (even the 1D X with its new v1.1.1 firmware), but AF is extremely slow. The IQ of the bare 100-400 is ok, but it takes a pretty significant hit witha 1.4x TC, and AF speed becomes so slow as to be largely unusable...I wouldn't really consider it an honestly viable option for birds/BIF.

Rogers idea about the 300mm f/4 with a 1.4x TC is a good one. That gets you 420mm of prime focal length, and if you use one of the Mark III TC's, IQ should remain pretty high.

Regarding better detail at shorter distances than long lenses at longer distances. If we use the 300mm f/4 lens as an example, you could technically get better spatial resolution at the sensor, as well as a higher S/N, by using the lens as a 300mm f/4 a little closer, rather than a 420mm f/5.6 a little farther. Simply due to diffraction, spatial resolution of the real image at the focus plane (the sensor plane) will drop as you stop down, assuming the lens is diffraction limited. At f/4, maximum diffraction-limited resolution is 173lp/mm. At f/5.6 maximum diffraction-limited resolution is 123lp/mm. Assuming you fill-the-frame with both focal lengths, getting closer with the 300mm f/4 should produce better quality, as you are resolving more detail and getting more light down the lens (assuming you use maximum aperture). Similarly, using a 500mm f/4 lens, being the same relative aperture, would allow you to resolve the same amount of spatial resolution and light at a greater distance. You could also use a 300mm f/2.8 lens with a 1.4x TC to get 420mm f/4, which again should produce the same amount of light at the sensor for a higher S/N along with the potential for more spatial resolution than the 300/4+1.4x, as well as offer you the option of dropping the TC to get even closer with more light.

The MFD of the 300 f/2.8 L II is about 6'5", while it is 5' with the 300mm f/4 L. The MFD of the 500mm f/5 L II is 12', but it will magnify the subject by 2.8x over a 300mm lens, so I don't think you would need to get as close for the same IQ or subject framing in any context.

[Andre van As]

Hi Jon
Thanks for the advice backed with solid reasoning. I suppose that I should take the path towards the highest IQ possible as I seem to be getting more into printing. Fast AF is a real plus which I experienced while acting as photographer for my grandson's 4th birthday using the 5DMk2 + 70-200 L IS f4 lens that I gave my son about 18 months ago. I cant imagine how much more versatile it will be with the newer camera software/hardware and upgraded AF lenses. I will look into the 300mm f2.8 option.

Regards

Andre

[Dan Brown]

Dan,

I don't think switching to Canon will solve your BIF problems. You will find that just like your Nikon setup, 400mm is too short for general BIF, you will have to crop a lot and IQ will be poor even if the lens is sharp. Plus your D800 AF which is a pro module is a lot better than the 7D for flight so it is likely that you will be disappointed.

Unless you plan carefully and go to places where birds are large, close, approachable or work on approach techniques-which you can do with your Nikon as well-I don't think you will be happy if your intention is to get high quality flight shots.

Hope this helps

Arash

Thanks Arash and all. Arash, I agree with you 100%, particularly after reading this thread! I won't be switching and will be saving my pennys for a big piece of glass. I have photographed over 650 species of NA birds, over 200 in flight (and some of them I even got close to!) in my 30 years now shooting with just 400mm (recently with the 1.5 digital crop aide) and fully understand the need to use the best field craft possible. Life will be SO EASY if/when I get the huge lens!

FYI neither of the prime 300mm lenses that I priced have focus limiter switches as far as I can tell, so that is not good for BIF!

[Dennis Zaebst]

Dan,

Just wanted to correct your statement about the 300 mm primes not having focus limiter switches. The Canon 300 mm f/4L IS does have such a switch: either 1.5 M to infinity or 3 M to infinity. I don't know about the 300 f/2.8 L IS. I have used the 300 f/4 L IS for BIF and have had good luck with it. I also use the EF 70-200 mm f/4 L IS, but I don't often use my EF 500 for flight shots. Maybe I need more practice...heh.

[Jon Rista]

The EF 300mm f/2.8 L II has a focus limiter switch. If I remember correctly, it supports "Full" range, "2-6 meters", and "6 meters to infinity".

[Roger Clark]

Dan,

Just wanted to correct your statement about the 300 mm primes not having focus limiter switches. The Canon 300 mm f/4L IS does have such a switch: either 1.5 M to infinity or 3 M to infinity. I don't know about the 300 f/2.8 L IS. I have used the 300 f/4 L IS for BIF and have had good luck with it. I also use the EF 70-200 mm f/4 L IS, but I don't often use my EF 500 for flight shots. Maybe I need more practice...heh.

I'm pretty sure Dan was discussing Nikon lenses (or 3rd party lenses for Nikon).

Roger

[Roger Clark]

Andre, I would strongly warn against using the 100-400mm lens with a TC. For one, using a 2x TC with that lens at 400mm means your maximum aperture drops to f/11. It is doubtful any Canon body would AF with that. The 100-400mm lens with a 1.4x TC is f/8, so only a 1D series body would officially AF with it (even the 1D X with its new v1.1.1 firmware), but AF is extremely slow. The IQ of the bare 100-400 is ok, but it takes a pretty significant hit witha 1.4x TC, and AF speed becomes so slow as to be largely unusable...I wouldn't really consider it an honestly viable option for birds/BIF.

Rogers idea about the 300mm f/4 with a 1.4x TC is a good one. That gets you 420mm of prime focal length, and if you use one of the Mark III TC's, IQ should remain pretty high.

Regarding better detail at shorter distances than long lenses at longer distances. If we use the 300mm f/4 lens as an example, you could technically get better spatial resolution at the sensor, as well as a higher S/N, by using the lens as a 300mm f/4 a little closer, rather than a 420mm f/5.6 a little farther. Simply due to diffraction, spatial resolution of the real image at the focus plane (the sensor plane) will drop as you stop down, assuming the lens is diffraction limited. At f/4, maximum diffraction-limited resolution is 173lp/mm. At f/5.6 maximum diffraction-limited resolution is 123lp/mm. Assuming you fill-the-frame with both focal lengths, getting closer with the 300mm f/4 should produce better quality, as you are resolving more detail and getting more light down the lens (assuming you use maximum aperture). Similarly, using a 500mm f/4 lens, being the same relative aperture, would allow you to resolve the same amount of spatial resolution and light at a greater distance. You could also use a 300mm f/2.8 lens with a 1.4x TC to get 420mm f/4, which again should produce the same amount of light at the sensor for a higher S/N along with the potential for more spatial resolution than the 300/4+1.4x, as well as offer you the option of dropping the TC to get even closer with more light.

The MFD of the 300 f/2.8 L II is about 6'5", while it is 5' with the 300mm f/4 L. The MFD of the 500mm f/5 L II is 12', but it will magnify the subject by 2.8x over a 300mm lens, so I don't think you would need to get as close for the same IQ or subject framing in any context.

I agree with everything Jon said, but there are some additional factors.

There appears to be a sweet spot in telephoto lens technology: 500mm. Check out Canon's MTF charts for the 500 f/4 version 2 at
http://www.usa.canon.com/cusa/consum...ef_lens_lineup
The new 500 is near perfect wide open! Compare that to the new 600 f/4, 400 f/2.8, 300 f/2.8 and 300 f/4. And as one moves to shorter focal lengths the larger angles get more difficult to correct all the aberrations. But longer than 500 the MTF charts are not as spectacular. Two factors are in play here. The bigger lenses (e.g. 600 f/4, 800 f/5.6) have a lot of glass and the long focal lengths magnify imperfections more so it is more difficult to make the perfect lens. (Side note: astronomers make big telescopes with mirrors due to the difficulty of making large telescopes with lenses.). Note the 300 f/2.8 version 1 and 2 have similar optical quality as it is more difficult to make a lens in this focal length to cover the field of view with near perfect image quality.

The factor working against longer focal length lenses is atmospheric turbulence. The longer distance to your subject, to more likely it is that atmospheric turbulence will limit detail.

So summary: the super telephotos have outstanding performance and image quality with a peak in optical quality around 500 mm, but atmospheric turbulence may limit the detail one can achieve and when that happens, closer is the only option if one wants detail on the subject.

Roger

[Dan Brown]

Dan,

Just wanted to correct your statement about the 300 mm primes not having focus limiter switches. The Canon 300 mm f/4L IS does have such a switch: either 1.5 M to infinity or 3 M to infinity. I don't know about the 300 f/2.8 L IS. I have used the 300 f/4 L IS for BIF and have had good luck with it. I also use the EF 70-200 mm f/4 L IS, but I don't often use my EF 500 for flight shots. Maybe I need more practice...heh.

Thanks for the info Dennis. As I stated, AS FAR AS I CAN TELL. I didn't see any mention of it on either the Canon or Nikon f4's.

So, FYI everyone, Canon has the total edge IMO in the running for the best cheap BIF rig!

[Pao Dolina]

It has been mentioned on photo forums that the 100-400 IS is actually shorter (around 390mm) than the 400/5.6 prime. Just something to consider when choosing between the two.

[Daniel Cadieux]

Thanks Arash and all. Arash, I agree with you 100%, particularly after reading this thread! I won't be switching and will be saving my pennys for a big piece of glass. I have photographed over 650 species of NA birds, over 200 in flight (and some of them I even got close to!) in my 30 years now shooting with just 400mm (recently with the 1.5 digital crop aide) and fully understand the need to use the best field craft possible. Life will be SO EASY if/when I get the huge lens!

Wise choice. Arash brought up an important point...I don't think I've seen anyone improve their images because they've simply switched sides (and that goes both ways).

[Andre van As]

I agree with everything Jon said, but there are some additional factors.

There appears to be a sweet spot in telephoto lens technology: 500mm. Check out Canon's MTF charts for the 500 f/4 version 2 at
http://www.usa.canon.com/cusa/consum...ef_lens_lineup
The new 500 is near perfect wide open! Compare that to the new 600 f/4, 400 f/2.8, 300 f/2.8 and 300 f/4. And as one moves to shorter focal lengths the larger angles get more difficult to correct all the aberrations. But longer than 500 the MTF charts are not as spectacular. Two factors are in play here. The bigger lenses (e.g. 600 f/4, 800 f/5.6) have a lot of glass and the long focal lengths magnify imperfections more so it is more difficult to make the perfect lens. (Side note: astronomers make big telescopes with mirrors due to the difficulty of making large telescopes with lenses.). Note the 300 f/2.8 version 1 and 2 have similar optical quality as it is more difficult to make a lens in this focal length to cover the field of view with near perfect image quality.

The factor working against longer focal length lenses is atmospheric turbulence. The longer distance to your subject, to more likely it is that atmospheric turbulence will limit detail.

So summary: the super telephotos have outstanding performance and image quality with a peak in optical quality around 500 mm, but atmospheric turbulence may limit the detail one can achieve and when that happens, closer is the only option if one wants detail on the subject.

Roger

Hi Roger - Thanks for weighing in. A similar discussion is going on in another thread -( http://www.birdphotographers.net/for...est-lens-brand ) where you created a table showing the difference between the various sensors and lens magnification factors taking into account the sensor's pixel size. In this table the 5DMk3 seemed to be the "worst" performer. However I remember a previous post (several months ago started by Art) where the difference between FF and DX? sensors was accounted for by the magnification factor of the crop that occurred due to the difference in sensor size, and if you corrected for this by using and appropriately sized telephoto lens utilize the same proportion of sensor on FF cameras as the that produced by the crop factor in cameras that are not FF then you get equivalent of ?better IQ with a FF camera?? Perhaps I missed the step in your calculations that corrected for the crop factor.

Re the AF of the 5DMk3 I read the following in Photography Bay's most recent news letter suggesting that the limitation of AF at f8 or less has now been removed. What I did not see was reference to the speed of the AF and if it was maintained.
'Improved AF Functionality Even when the EOS 5D Mark III is equipped with an extender and lens making possible a maximum aperture of f/8, the firmware update supports AF employing the camera’s central cross-type points (currently compatible with maximum apertures up to f/5.6). Accordingly, the update will allow users to take advantage of AF when shooting distant subjects, benefitting sports and nature photographers, particularly when using telephoto lenses.


​Balancing these issues makes the choices very complicated. The escalating price of the "better" lenses makes it even more difficult.

Regards
Andre

[Dennis Zaebst]

Originally posted by Jon Rista:

Andre, I would strongly warn against using the 100-400mm lens with a TC. For one, using a 2x TC with that lens at 400mm means your maximum aperture drops to f/11. It is doubtful any Canon body would AF with that.

I agree with part of this statement, and it is wise advice, but I do know my 1D IV will focus with stacked 1.4x and 2x TC's, which on a 500 mm lens, is f/11. I tried it just the other day, and I was surprised, but it worked. Now this was in fairly bright sunlight of course. I don't know if it would work well in dim conditions. I suspect it would work with a 1D III or earlier too. This is due to the fact that the 1D ignores the second stacked teleconverter (which I have confirmed in the exif data), and the camera thinks only the 2x is mounted (e.g. the camera reports 1000 mm @f/8 with a 500 mm f/4 lens and stacked TC's, even though it is actually at f/11), and that it is seeing a darker scene.

Of course, I recognize that the OP (Dan) said he is interested in the 7D, not a 1D series, and how it would perform with an f/5.6 lens with TC's. So this would not apply to his original stated scenario.

[Roger Clark]

Hi Roger - Thanks for weighing in. A similar discussion is going on in another thread -( http://www.birdphotographers.net/forums/showthread.php/103884-Birding-camera-system-(DSLR-vs-m4-3)-significance-of-DxOMark-and-best-lens-brand ) where you created a table showing the difference between the various sensors and lens magnification factors taking into account the sensor's pixel size. In this table the 5DMk3 seemed to be the "worst" performer. However I remember a previous post (several months ago started by Art) where the difference between FF and DX? sensors was accounted for by the magnification factor of the crop that occurred due to the difference in sensor size, and if you corrected for this by using and appropriately sized telephoto lens utilize the same proportion of sensor on FF cameras as the that produced by the crop factor in cameras that are not FF then you get equivalent of ?better IQ with a FF camera?? Perhaps I missed the step in your calculations that corrected for the crop factor.

Hi Andre,
What your are describing is Etendue. If one keeps the same pixels on subject with the same diameter lens and the same exposure time, then image quality in terms of detail on the subject, diffraction effects, depth of field and signal-to-noise ratios are all identical (assuming equal quality lenses). It has nothing to do with crop factor. My article on etendue is at:
http://www.clarkvision.com/articles/...m.performance/

Re the AF of the 5DMk3 I read the following in Photography Bay's most recent news letter suggesting that the limitation of AF at f8 or less has now been removed. What I did not see was reference to the speed of the AF and if it was maintained.
'Improved AF Functionality Even when the EOS 5D Mark III is equipped with an extender and lens making possible a maximum aperture of f/8, the firmware update supports AF employing the camera’s central cross-type points (currently compatible with maximum apertures up to f/5.6). Accordingly, the update will allow users to take advantage of AF when shooting distant subjects, benefitting sports and nature photographers, particularly when using telephoto lenses.

Yes, that firmware update will be available in the spring. I think that quote was derived from the Canon release.

​Balancing these issues makes the choices very complicated. The escalating price of the "better" lenses makes it even more difficult.

Yes, one can over analyze the problem, but in the end the larger factor is what works best in one's hands, one's experience, and practice. For example, I have taken a 500 f/4 on safari to the Serengeti, but now only take a 300 f/2.8. With the smaller, lighter lens I can react faster and as a result come home with better images, including more BIF. On paper, the 500 should out perform the 300 in terms of detail on subject and AF speed (e.g. 500 f/4 bare versus 300 with 1.4 and 2x TCs), but in practice, I find for the safari environment the smaller lens works better for me. In other situations, like birds at Bosque, where one can stay in one spot with a tripod mounted lens, I do well with the 500.

Roger

[Andre van As]

Hi Roger
Thanks for the link which I read with interest and when my headache subsides I will read it again - but I get the point. So it seems that the fastest (largest diameter) lens is part of the equation for delivering the photons at an optimal ISO to the pixels best suited to keep S/N ratio high.

Regards

Andre

[Corey Hayes]

I had the 400 5.6 and did not like it at the time and got he 500 f4 instead. I found it hard to get sharp pictures because of the lack of IS if you need an around lens I would go for the 100-400 you will get a far higher keeper rate.