More trials with Stacked Converters
 

Following my trials with the 1.4 and then 2x converter I decided to have a bit of fun by stacking the two to give a focal length of 1120mm (1792 if you inc the crop factor) with my 400mm f5.6 lens. Think results may have been a bit better if I had a remote release but I was still suprised at the IQ. Think what this shows is the quality of the Canon 'L' glass.

Psst: What lens were you using?

Opps - Canon 400mm f5.6 prime (have now added to original post)

I'm surprised at the IQ too. I have Arthur Morris's bird book, and he has some example of pictures with stacked converters on a 600mm lens. They are remarkable. Canon's longs seem to take converters well.

Hi Roy, surprised, I am amazed! I've just got my self a Canon 300mm f/2.8IS with a 2x wide open I cannot see any quality degradation at all, my next task is to stack the 1.4x and 2.0x, its dull as dishwater out there today so I will have a go when it brightens up.:)

Cheers

Hi Nick - IMO the lens that you have is one of the very best and if I were to upgrade the 300mm f2.8 IS is the one I would go for. I am sure you will have stunning results with stacked tc's. By my reckoning you should be able to retain AF with the mkIII even with the two converters (f8). How do you get on hand holding this lens from the weight point of view?
Cheers
Roy C
p.s The 'Goldie' shot is a cracker

Hi Roy, Will I loose all af on the 30D when I stack the tc's? I suppose it doesn't really matter as I should have the MKIII soon. Hand holding is not to bad but I don't think I could hand hold all day, It would be mounted on the monopod most of the time.

Cheers

Not sure how stacked converter actually report back to the camera Nick - I guess it is just the one attached to the camera that counts. If this is the case then you should get AF on the 30D without even taping the pins. Remember that you will need a non Canon tc to attach to the Camera to enable stacking.

Hi Roy, As far as I can make out the MKII extenders which I have are ok stacked, looks like Canon have done a mod of some kind.

Cheers

Hi Roy, I had a quick go this morning with the 300mm + 2.0x and 1.4x, AF was not that good, a lot of hunting. I can't get my head round what the aperture/exposure is doing, I know the camera says f/5.6 but is this true or should this really be f/8 or are all the auto exposure settings wrong when stacking tc's?

Cheers