Hi all, I'm after some advise please, I use a canon 300mmf4L and a canon 70-200mm f/4 lens, I want to know your opinions on which extender will work best on these lenses please, i.e do i lose AF, etc, I use my 300mm mainly for racing shot, but want some extra length, any tips or advise would be great please
canon 1.4 or 2x extender?
- Thread starter canonguy
- Start date
petersmart
Suspended / Banned
- Messages
- 5,000
- Edit My Images
- Yes
On both the extenders you will lose light, on the 1.4x the loss will be equivalent to 1 stop and on the 2x equivalent to 2 stops.
So on the 2x both lenses will become equivalent to f8 lenses and on 1.4x will be equivalent to 5.6
So basically it will depend on how the AF on your camera can handle the loss of light.
I believe that Canon provides data on this so you could also check that.
.
marksweb
Suspended / Banned
- Messages
- 227
- Name
- Mark
- Edit My Images
- Yes
What body have you got?
I've got a 70-200 f4 as well & have been considering a 1.4x for motorsport this year. I've got a 7D Mk2 & as I understand it a 1.4x would still drive the AF and work out nicely, but I'd love to try it out before taking the plunge!
I've got a 70-200 f4 as well & have been considering a 1.4x for motorsport this year. I've got a 7D Mk2 & as I understand it a 1.4x would still drive the AF and work out nicely, but I'd love to try it out before taking the plunge!
NFI
Suspended / Banned
- Messages
- 356
- Name
- James
- Edit My Images
- Yes
I have both and I would go for the 1.4x if I were you, I previously used the 2x on a old 30d with 70-200 2.8 with good results although the AF was not great.
I'm currently using the 1.4 with 5d mk3 and 1dx bodies and works very good indeed.
I'm currently using the 1.4 with 5d mk3 and 1dx bodies and works very good indeed.
- Messages
- 15,745
- Name
- Phil
- Edit My Images
- Yes
There are a few models that retain AF at f8
AHILL
Suspended / Banned
- Messages
- 1,110
- Edit My Images
- No
the 5D3 will autofocus with the 300 f4 + 2X extender and is OK'ish but a better image is achieved using the 1.4.
Gaz J
Suspended / Banned
- Messages
- 3,294
- Name
- Gary
- Edit My Images
- No
7D MkII will AF at f8.
I would go for the 1.4. The bodies that are showing on your profile won't AF at f8 so a x2 is pretty pointless unless you're a dab hand at manual focus. Have read that some non OE converters can be made to AF at f8 but don't know how effective they are.
I would go for the 1.4. The bodies that are showing on your profile won't AF at f8 so a x2 is pretty pointless unless you're a dab hand at manual focus. Have read that some non OE converters can be made to AF at f8 but don't know how effective they are.
- Messages
- 9,425
- Name
- Robin
- Edit My Images
- Yes
I have both these lenses and the Canon 1.4x III. I have used all the combinations on a 70D and now a 7D Mark II.
The 70-200mm F/4 L IS + 1.4x III is a great combination with no issues. Obviously the lens becomes F/5.6.
The 300mm F/4 L IS + 1.4x III works but AF with it is fractionally slower on the 7D2. The AF pts areas are not compromised (as they are with the 400mm F/5.6 L becoming F/8). If you are very critical there is a loss of image quality in distant subjects. Some people like the combo but I don't, probably because I have the magnificent 400mm prime.
Personally I would not advise a 2x on either of these lenses - What seems good in theory doesn't always deliver expectations in practice.
The 70-200mm F/4 L IS + 1.4x III is a great combination with no issues. Obviously the lens becomes F/5.6.
The 300mm F/4 L IS + 1.4x III works but AF with it is fractionally slower on the 7D2. The AF pts areas are not compromised (as they are with the 400mm F/5.6 L becoming F/8). If you are very critical there is a loss of image quality in distant subjects. Some people like the combo but I don't, probably because I have the magnificent 400mm prime.
Personally I would not advise a 2x on either of these lenses - What seems good in theory doesn't always deliver expectations in practice.
Last edited: