Hi all.
Im thinking of getting a teleconverter for my Canon 30d and 100-400 IS lens.
Ive heard rightly or wrongly that with this lens the autofocus does not work with the canon 1.4x and 2x teleconverters. IS this right?
If so can you still tape to override this?
Does anyone have a link to a recent article or thread dealing with taping converters?
Thanks so much for your advice. All the best Mark
Hi Mark, when using a 1.4x tc with a f5.6 lens you will lose 1 stop of light which means you will be shooting at f8. With the 2x you lose 2 stops which is f11.
Non 1 series Canon cameras will only AF up to f5.6. This means that if you add a tc you will be outside of the AF range for the Camera.
To overcome this you can fool the camera into not knowing a tc is present, there are two methods to do this:
1) Use a non reporting Converter (such as the Kenko 1.5)
2) Tape three of the pins on a reporting converter to make it non reporting. Attached is how to do this.
Apparently this works fairly well on the 30D and 100-400 but I belive many users prefer the Kenko Pro 1.4 as opposed to the Canon 1.4 for this purpose.
Hope this helps
EDIT: a 2x tc is not recommended as the IQ will take a big hit.
Mark,
I have a 20D and a 100-400 IS lens. I often use the 1.4X Canon TC and it works great. I have taped the contacts and AF works very well in good light. In so-so light, I switch to manual focus. I have very good results as long as I use a tripod and a remote shutter accessory. The IS is always on on my lens even if Canon doesn't recommend it. It takes some time to get used to using it with good results. Be patient !
I have also tried the 2X TC but it is very soft with the 100-400. I got rid of it.