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04/12/2004 09:11:28 AM · #1 |
I just bought a Canon 1.4x extender II for my Canon 100-400L IS.
I took about 250 bird pictures this weekend and I didn't get a usable one with the Extender.
Has anyone else noticed that their extender degrades the quality of their photo? I didn't get one usable print.
Did I get a bad copy?? Has anyone else got a bad copy?? Is this normal for the Extenders or is it my lens? The lens has perfect pictures without the extender?
Do I have to change the setting or something??
Any help would be much appreciated.
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04/12/2004 09:13:23 AM · #2 |
Couple of things
are the pictures out of focus, or just blurry ?
I think by default the 1.4x tele stops the autofocus working on the 100-400F4L. There is a fix, with some duct tape though.
From the first tip at //www.fredmiranda.com/TipsPage/
1) How to activate auto focus (AF), when using 1.4x or 2.0x teleconverters with f/5.6 or slower lenses.
It is simple. Just place a small transparent piece of tape on the last 3 pins of the converter. The tape should be placed on the left hand side of the converter when looking at it from the lens connection side. With these three left pins covered, the converter continues to operate on the D30 with the AF activated. It works great with the Canon 100-400mm f/4.5-5.6L IS.
Message edited by author 2004-04-12 09:14:38.
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04/12/2004 09:21:14 AM · #3 |
Yeah the pictures are very blurry.
I will try the auto focus fix..
Thanks a lot Gordon. |
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04/12/2004 11:10:24 AM · #4 |
Gordon,
Will this work with the rebel?
The site says this is for the D30. |
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04/12/2004 11:17:14 AM · #5 |
worth a try. It is a lens issue really - with the extender, the lens is too slow for the AF to work properly, so the camera doesn't even try.
The tape stops the lens indicating that it is too slow, so the AF should still be able to work (at certain zoom ranges)
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04/12/2004 11:29:04 AM · #6 |
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04/12/2004 05:28:37 PM · #7 |
Corwyn - please let us know. I am about to buy a 300d, a Canon 70-200 L f/4, and the Canon EF 1.4 teleconverter. I hadn't heard anything bad until your post. Yeah.. please get back with the "tape" mod.
Thanx,
R. |
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04/12/2004 05:32:29 PM · #8 |
Originally posted by RickDN:
Corwyn - please let us know. I am about to buy a 300d, a Canon 70-200 L f/4, and the Canon EF 1.4 teleconverter. I hadn't heard anything bad until your post. Yeah.. please get back with the "tape" mod.
Thanx,
R. |
Rick - that combo should not need any modifications to get autofocus to work. The problem with the D30/D60/10D (and I assume 300D) is getting autofocus to work with any lens slower than f/5.6.
A 70-200 F/4 + 1.4x teleconverter is an effective F/5.6, which should autofocus fine, given enough light of course.
Rich.
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04/12/2004 05:33:11 PM · #9 |
It might be worth reading the footnote on
this canon page
It mentions which lenses work or don't work with the teleconverters, as well as the associated problems.
The majority of the EOS cameras need a wide open aperture of f5.6 or brighter for the AF to work reliably.
A 1.4x tele reduces the max aperture of a lens by one stop
A 2x tele reduces the max aperture of a lens by two stops.
So the 1.4x breaks the AF on any lens that is f5.6 or slower
and a 2x breaks the AF on any lens that is f4 or slower.
The masking tape fix stops the camera from realising this, but you might still get unreliable AF with it - I don't know too much about that.
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04/12/2004 06:08:47 PM · #10 |
Originally posted by Gordon:
...The masking tape fix stops the camera from realising this, but you might still get unreliable AF with it - I don't know too much about that. |
With certain combinations the masking tape is unnecessary; for example I've used a Tamron 1.4x TC with the Canon 28-200mm 3.5-5.6 lens at 200mm. The Tamron TC does not inform the camera of its presence so the lens still reports f/5.6 @ 200mm, and AF still works. Kinda. Hunts more, needs higher contrast to reliably focus, but in good light (when else would you use this combo??) it works decently. Needs to be set to center focus point!
BTW the Tamron TC I have is the "cheap" one. It's actually pretty highly regarded, but supposedly is s bit softer in the corners than the Canon 1.4x (versiion I or II). This is hearsay, I don't own the Canon (currently, LOL).
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