isaac sibson

The AF does indeed work on the max effective aperture. I'm not sure

exactly how the system works, but it is not possible to "dodge" the

system with a smaller aperture. The problem with the third party TCs

trying to get around the AF thing by not reporting the change in

effective aperture is that the metering records the supposed full

aperture. While it will not be inaccurate in it's results, the number

it reports is. EG, a Canon 300F4L IS used with a third party 1.4X and

with a Canon 1.4X. With the third party, it will report the aperture

as being F4, but with the canon, it will report 5.6. Both will expose

accurately, because the light falling on the sensor is the same.

However, it becomes an annoyance to those who record exposure

information, or to a camera that does (1V). Also is a pain if you're

using flashes (although admittedly it is not often that one will use

a flash with a TC). Coming back to the AF limit, it has nothing to do

with TCs. If you were to go out and buy one of those bottle-glass 800-

1200 zooms, which are something hideous like F11-F27, you'll find

they're manual focus because there's no point putting AF in. The

aperture is not big enough. The only confusion arises because of the

EFFECTIVE aperture of the lens with a TC, which the canon TCs report

to the camera, and third party TCs don't. For the newbies, 1.4X TC

effective aperture is lens aperture -1 stop. 2X TC is -2 stops.

<p>

Many people are confused by this non-linear relationship. "Surely the

2x TC is a better deal of magnification vs light loss?" They are in

fact the same. Stack 2 1.4TCs and you will loose 2 stops. 1.4x1.4

is....2!

I have an EOS 5 and there isn't a panel on it that doesn't move or

creak etc. (excluding the vertical grip, which is satisfyingly

solid). I haven't had any light-leaking or lack of sharpness

problems. I think that it's funny that e7 owners are complaining,

when all cameras (even the rebels) subsequent to the 5 have been much

better than it, when the 5 was a semi-pro camera! I have handled 2

EOS 50e (Elan IIe), and they've both been a LOT more solid feeling

than the 5. I think the 30/e7 will be similar to that. I certainly

don't think Canon would take steps BACK on this front, as in the days

of the 5, it was a major point in favour of Nikon. Next up for me,

and EOS 3 I think.

The EOS 1N and 1V will. I'm not sure about the 3. 5, 50/E (Elan II/e)

will NOT. I assume 30/33 (elan 7/e) will not either. my old 1000FN

(Rebel sII?) would not, so presumably the rebels won't. I think the

10 will (EOS elan), not sure about the 100 (?). I think the older

ones (600, 620, 630, 650) will.

I'd like to point out also that the 135 F2L is one of the finest

lenses ever made, in terms of it's optical quality. The build quality

is also much better than the 2.8, and the 2.8 IS NOT USM. The 135F2

was a lens I had my eye on for a bit, but I eventually decided that

it was too heavy, and not really a lens I'd use enough to justify

having it. I bought a 70-200F4L instead (the two lenses were vying

for the job of replacing my Sigma 70-300 APO since I got my 300F4L

IS). The 135F2 is also Canon TC compatible, which the 2.8 is not (the

135 f2 is the shortest prime that will accept the TCs. The 2 70-200 L

zooms and the 35-350 and 100-400 will also accept them, these being

the only lenses under 200mm that will take them (possibly macros and

TS lenses will also)).

A shop recently tried to sell me the 100-300 f5.6L when I asked about

the 70-200F4L. There's no way that I'd buy into a lens that was that

old. Similarly, there's no way I'd buy into a camera body such as the

EOS 5 now (I have one though, so no flames about what a great camera

it is...I'm just saying that I'd buy a 30 or a 3 instead now). To me,

USM is a must. However, as the earlier post said, it depends what

you're doing. I've used the 100-300 USM, and it's a nice lens to use.

Quick, silent, handles well. I have not used the old L lens, but I

really wouldn't. My outlook is, admittedly, based on the fact that I

now have a 70-200F4L and 300mm F4L IS and a 1.4X TC, which allows me

100-280 f5.6, and 420mm f5.6 IS also. My vote would go with the 100-

300 USM, for the things I do, but it does depend on whether you need

that speed.

I had power-drain problems for a while with my EOS 5. It's due to IS,

lots of AF, Eye Control, and, THE TEMPERATURE. The lithium batteries

have poor temperature range...cold, or hot, will cause the battery to

be drained very fast. I got about 2 rolls from one battery in the

middle of winter, using my 300mm F4L IS. Also, try changing battery

brands...some brands don't make good contact with the terminals. I

like the panasonic ones best for use in my EOS-5. The panasonics seem

to work better than others, esp samsung (which seemed to be the

worst).

I have the 300F4L IS and a 1.4X TC (mk I), while my father has a 100-

400L IS and a 1.4X TC (mk II). The results from both of these combos

are very good, and higher quality than any consumer grade zoom

(obviously). They have stood comparison to the Canon 100-300 USM (not

L) and the Sigma 70-300 APO Macro, and are considerably better.

Apparently the new 2x TC (mk II) is an improvement over the previous

one (there's no optical difference between the two series of 1.4X

TCs), so I should imagine the 300f4L + 2x mkII should give good

results. I need to replace my EOS 5 with a 3 (or a 1V, but pigs might

fly) before I buy a 2x TC. My vote would go with the 300f4L IS (not

that I'm biased...it's the same choice I made between the two lenses,

and I'm happy with the decision I made), since optical quality is

your priority. I point out that if you're hand-holding, the handling

of the 300mm is rather better, because the lens is well balanced,

whereas (esp. at the 400mm end) the 100-400 is very front-heavy,

which is a strain on your arms, and quickly tiring. This is made

slightly worse by the additional length (although the 1.4x isn't very

long).

I have many wonderful shots taken with my 300f4L IS using an (unfortunately) borrowed 1.4x Canon TC. I will be buying one at some point, to go with my lens and EOS 5 body.

Well worth it!