Got my new 400 L-disappointed that

[pttenn]

I can't keep autofocus with a Kenko Pro 1.4 extender on it. I thought I had read that the Canon extenders wouldn't work but other brands would. Other than that it seems to be a sharp lens. Any comments?
Karen

[condyk]

It won't work. There is an older Tamron/Kenko model that will work, but not the latest versions with electrical connections.

[pttenn]

Rats!

[Tom W]

Somewhere in the teleconverter FAQ sticky thread at the top of the lens section, there is information on which teleconverters will "fool" the camera and allow autofocus. I believe that the "cheap" version of the Tamron 1.4X will work. There are a couple of others.

What will not work are the Canon, Sigma, and a couple of higher-priced "pro" versions from Kenko, Tamron, and perhaps others.

[pttenn]

Well, guess I have to buy a cheap 1.2..how ironic. So will that ruin the quality of the pictures? (assuming I can take a decent picture...lol)
Karen

[dputz]

Is it a 400 f5.6? If so, AF will only be maintained with a 1D-series body...regardless of the brand.

[luant16]

rather than buy another one try to use tape first, i remember you can tape the last 3 pins but i dont know which one, there may be some people who have experience with it who can help you

[pttenn]

Seriously? Put tape over the connectors? Wouldn't that hurt the connectors?
Karen

[canonloader]

I've read about the tape too, but heard it was only one of the pins. But I don't think a 1.2 anything would even be worth the effort or the money for just a few extra feet of closeness.

[pttenn]

I've read about the tape too, but heard it was only one of the pins. But I don't think a 1.2 anything would even be worth the effort or the money for just a few extra feet of closeness.

If I could get close enough I'd have been happy with my 200L 2.8! :confused: And about a grand richer! Hard to sneak up the vertical side of a silo....
Karen

[Roy C]

Seriously? Put tape over the connectors? Wouldn't that hurt the connectors?
Karen
I have taped the last three pins on my Canon 1.4 tc for use with the 400mm f5.6. Cannot see how it would harm the connectors.
You will find that the af will hunt a bit but there are a few tricks to help it along.
1) Roughly manual focus first and then auto focus helps a lot to eliminate the hunting.
2) For birds in flight I depress the shutter and when it begins to hunt, release the shutter and then depress again.

There must be lots of people using converters with the pins taped and I have never heard of a problem.

[canonloader]

And about a grand richer! Hard to sneak up the vertical side of a silo....

Thats what I use the crop button for. ;)

[LightRules]

Karen, try this and see how you like it. It should work fine http://www.pbase.com/lightrules/image/53316917/original

[Roy C]

Is it a 400 f5.6? If so, AF will only be maintained with a 1D-series body...regardless of the brand.
Not so - the cheap Kenko has not got the contacts to tell the camera that it is there so the Camera still thinks it is f5.6 and will af.

[akhater]

yes tape them or, better nail polish them :)

[Permagrin]

Well, guess I have to buy a cheap 1.2..how ironic. So will that ruin the quality of the pictures? (assuming I can take a decent picture...lol)
Karen

I believe it was CDS who said, in one of his posts, that it wasn't great for the AF motor to try to get it to focus when it wasn't designed to...can't remember for sure who said it, but it made an impact on me...wouldn't want to hurt my camera or lens....

[Tom W]

I believe it was CDS who said, in one of his posts, that it wasn't great for the AF motor to try to get it to focus when it wasn't designed to...can't remember for sure who said it, but it made an impact on me...wouldn't want to hurt my camera or lens....


I tried the pin-taping trick on my 100-400L with a teleconverter, and it hunted excessively. Sometimes, the AF would oscillate back and forth very quickly, so I quit doing it. That was on a 10D, which had a less-capable AF system than the 20D/30D. The 400/5.6 may fare better, and I'd say that it's worth a try.

I think that John DeFord was the one that had trouble with a 100-400 and taped contacts, a couple of years back. You may PM him and ask.

[ScottE]

Having started taking photos before AF was available, I don't understand why people can't use manual focus any more. It is still better in some tricky situations.

[pttenn]

Having started taking photos before AF was available, I don't understand why people can't use manual focus any more. It is still better in some tricky situations.

I agree, and will go ahead and use manual focus with the 1.4 Kenko for static situations...but for birds in flight you really need that auto. (or us newbies do..lol) I really need the reach of the 400+ the 1.4 to get close enough to shy birds. Guess I'm not sneaky enough...I may try the tape trick but sure don't want to damage this expensive (to me, anyway) lens.
Karen

[NordieBoy]

Not so - the cheap Kenko has not got the contacts to tell the camera that it is there so the Camera still thinks it is f5.6 and will af.

Will "try" to AF.
Whether there's enough light for that to be successful is another matter :)

[NordieBoy]

Having started taking photos before AF was available, I don't understand why people can't use manual focus any more. It is still better in some tricky situations.

Because some of us have cameras where the viewfinder is not suited to manual focus?
Or the expense of getting a split prism focus screen installed.

[Tom W]

Having started taking photos before AF was available, I don't understand why people can't use manual focus any more. It is still better in some tricky situations.

I shot with manual cameras as well, so I can point out a few things that make it more difficult in today's cameras:


Smaller viewfinder, at least in the 1.6X cameras.

No focus aid in the viewfinder. I had a microprism in my FT-QL and there's a split image prism in my old Argus.

Older lenses had a longer vernier to the manual focus ring. You could hit that pinpoint sharpness more easily.

We look at our images at 100% now, a level which wasn't normally reached with film (except for when using the loupe or viewing slides).

We didn't lose 40% of our viewfinder brightness due to the partial mirror (which ironically passes about 35-40% of the light through to a secondary mirror and on to the AF sensors).


All that said, I still occasionally manually focus the 5D and the 30D, but it's a more time-consuming task, and the precision is more difficult. OK for stationary objects, but not so good for fast-moving sports where AF works very well.

[MeanGreeny]

Taping the 3 pins causes no damage whatsoever.

Canon only do it to maintain the good name & reputation of their AF systems i.e. so that it works well or not at all.

Use the centre sensor only to improve AF performance when using the 'tape trick'

[basroil]

yes tape them or, better nail polish them :)

tape is better, when you want to get rid of it, nailpolish is harder to take off and put back on... and don't even think of using nailpolish remover...:rolleyes:

[Lightstream]

Kenko 1.5 SHQ Teleplus here, no pins (in the first place), no tape, whoohoo :)

Intend to stick this one on my 100-400 for backup 600 f/8 IS if I need it.

[NordieBoy]

Kenko 1.5 SHQ Teleplus here, no pins (in the first place), no tape, whoohoo :)

Intend to stick this one on my 100-400 for backup 600 f/8 IS if I need it.
No autofocus?