What is it about 400mm

As I have a Canon 7D the smallest Fstop I can use is f5.6. My eyes are not good enough for manual focus. The 70-300L is a lovely lens, but it is just not long enough at times.

There are two lenses I can afford, the 100-400L & the 400L f5.6. Both are very old and due to be replaced.

When I look at something over 400mm the price is well above my budget.

So my question is why the big jump in price? Is it because the lens elements are so large? Why is there no 500mm f5.6?

Is some learned person who can help to answer my question?


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Is it the focal length that drives price or aperture? Since there are 400mm at f/2.8 that are in the 5 digit price range, and at 200-400 f/4 also in the 5 digit price range. There are also Sigma's and Tamron's with focal lengths that get up to 500 & 600 mm, but apertures at f/5.6 + at a reasonable price under $2k (closer to $1k). Canon's offerings suggest the same... that is, as the aperture goes up so does the price.

I would not be one of learned people you refer to, but to me the logic makes sense. Larger apertures leaves a larger opening in the lens. That is especially true with large focal lengths... f/aperture means there is a big opening that gets proportionally bigger with focal length. As a result the glass to cover that large opening gets bigger and more costly. That is just my simplistic view and not the results of a lot of study, just looking logically at what is physically happening inside the lens.

Pat

Don't forget the Tamron 150-600mm. Very nice lens with stabilization and a good deal more reach. Same general price range.

Since you have the 70-300 zoom I would consider the 400mm f/5.6 prime. It's very sharp and a good choice for birds. I have seen many beautiful images using that lens and a 7D

The big jump in price is due to bigger and more complex optics for the 500mm f/4

Pat has it. With a telephoto lens design, the entrance pupil sits essentially at the front element. The entrance pupil needs to be filled with light, so front element size must be at least focal length / f-number. A 500/4 needs a 125mm front element, and all the elements in front of the iris diaphragm scale appropriately (particularly the expensive fluorite elements). 500/5.6 = 90mm, still substantially larger than the <77mm of the 400/5.6 lenses. That's why Tamron/Sigma use f/6.3 at the long end...600/5.6 = 107mm (same as 300/2.8), but 600/6.3 = 95mm.

Thanks everybody.

Since contracting L disease a few years ago I'm unable to look at another manufacturer, I love the IQ of my 70-300.

One thing I have noticed about Canon's White Lenses over the last few years is that they seem to be reactive to the market, there hasn't been anything new since DO (2001) and before that IS (1998). If another company produces a lens that has a better IQ than the Canon equivalent (if there is one), Canon will respond very quickly with a better product. The 200L f2 was in response to the Nikon lens, the 70-300L in response to Tamron and the 200-400L again in response to Nikon.

I feel that this is the reason why so many of their lenses are so old, no competition.

I like the idea of the 400L f5.6 but this is only a small step going from 300-400mm. It would also require me to buy a quality CF Monopod, as there is no IS. The last point against this lens is that it was designed in 1993 and must be Canon's oldest lens, its now 21 year old technology.

I'm still very confused as to what I should do next:confused:.

Will caution that Zeiss lenses are the only known cure for the dreaded L disease.

Your options are rather limited with longer focal lengths unfortunately. It can offer great savings, sometimes, if you are willing to play the waiting game for a series 1 400, 500, or 600mm lens to become available. I do frequent used equipment listings and do a fair bit of buy, try, and resell just to be able to check out stuff at no cost. Once a year or so an older veteran lens will come up at a decent price. Don't know if it works out that way Down Under though with the different market there but eventually the nature photographers around here are upgrading to the new lenses to remain competitive in their markets. Given the usage factor their lenses do sell for substantially less than an amateur's pristine lens that has rarely been out of the case.

Thanks everybody

Have made the decision to get a 400mm f5.6 L.

I have also been reading Bryan's reviews on the other things I need like Monopod's and CP Filters. After reading about B+W filters I checked out the local prices and the prices from the links Bryan provided. So buying two B+W CP filters from the US will save me more than A$150.

So if you live in Aus make sure you check the overseas prices as well.

Thanks for the links Bryan.

Congrats on the new glass!

Congrats! I am sure you will enjoy the new glass. Post some photos when you get a chance as I am sure the community would love to see you enjoying your new prize.

Just some food for thought...I have heard that you can focus with the 400mm with a Kenko or Tamron style 1.4xtc using anything but the middle focus point if you want to add some additional length to your lens. It would make it a f/8 lens, but sometimes you go that high anyway. Camera shake does become a concern at that point, but with a monopod I am sure you can compensate. I haven't read much on the subject here, but on Fred Miranda and POTN they talk about doing this.