Noob Question.

[Dale.]

I'm not a noob but I am trying to understand something.

I stumbled across something today. I'm looking how to get the most reach with what I have. I un-retired my 7D for the experiment, put my 2xTC (Mkiii) on it, then my 100-400, which on a Canon crop body and if my math is right, gives 1280mm eqivalent on 35mm at the long end.

The major drawback is though of course, no AF, unless I use liveview. Liveview is good but not much use on a bright day in a potentially fast moving wildlife situation. It can be done of course but I prefer the viewfinder.

The liveview AF got me thinking though. Would a mirrorless camera AF with this combination, as essentially, the viewfinder on a mirrorless camera is liveview. So I grabbed my Fuji, put on the adapter (Canon EF to Fuji XF) which isn't a dumb adapter. Hey presto, a Canon lens + Canon 2x TC will AF on a Fuji body. There may be drawbacks and pitfalls but I've not found them yet as I've not been able to try it in anger but for the purpose of the experiment, the combo works.

I am reluctant though to keep using it this way, it may end badly with all that opposing brand electronics going on.

So my question is, given how finnicky TCs can be, is this combo likely to work on a Canon mirrorless body?

I have my 5D of course, and can use the TC with that but with the 100-400, again no AF, unless using liveview, same with the 150-600 of course. I'm in a situation at the moment where I need relative lightness, compactness (long story which if it goes to plan, will be revealed) and as much reach as I can squeeze out, so I'm wondering is it worth picking up a second hand Canon M5 or similar, or do I go for the 600L f4?

 

[Brentor]

Lightness and compactness ≠ 600L f4, but I wish I had one.

 

[ancient_mariner]

So my question is, given how finnicky TCs can be, is this combo likely to work on a Canon mirrorless body?

I'd say it's unlikely to work because Canon have probably disabled such a move, but feel free to prove me wrong.

 

[ecoleman]

The mirrorless cameras use the same focusing method whether you are looking through the EVF of the rear screen so yes it should work fine.

canon have just released 600mm and 800mm fixed f11 Lenses which I guess also backs that up.

 

[Dale.]

Lightness and compactness ≠ 600L f4, but I wish I had one.

I'd say it's unlikely to work because Canon have probably disabled such a move, but feel free to prove me wrong.

The mirrorless cameras use the same focusing method whether you are looking through the EVF of the rear screen so yes it should work fine.

canon have just released 600mm and 800mm fixed f11 Lenses which I guess also backs that up.

Interesting.

One other thing I've noticed is that the aperture can be used at it's widest, even at the long end of the lens, according to the display in the viewfinder, so effectively. Whether or not this actually physical or just electronic confusion within the combination, I'm not sure. I could always put it into aperture priority and change the aperture to test that one. If the exposure changes too, then the TC isn't affecting the aperture like it would on a native body/lens.

 

[the black fox]

Luckily don’t suffer those problems since changing to Olympus dale with its 2x crop factor using a 1.4 tc on a 100-400 lens gives a effective 1160mm reach in FF terms with snappy a.f and sharp pics hand held

 

[ecoleman]

Luckily don’t suffer those problems since changing to Olympus dale with its 2x crop factor using a 1.4 tc on a 100-400 lens gives a effective 1160mm reach in FF terms with snappy a.f and sharp pics hand held

The in camera crop factor is no different to cropping in post. You are still loosing pixels.

 

[DizMatt]

it depends.
my full frame canon is 20MP
Some cropped APS-C sensors are greater than 20MP but not by much normally.

If you're loaded, then the 600mm f/4 and a Canon R5 would give you it all, including 45MP of cropability and that all important Eye tracking AF.
Or the canon lens with the drop in TC , still money for a Canon EF 200-400mm f/4L IS USM 1.4x Extender Lens


Honestly with that setup, I would dump the canon kit and go all in on the Fuji lens, by buying the Fujifilm XF100-400mm f/4.5-5.6 R LM OIS WR and then putting a 1.4xTC on that.
For the weight and price, I think nothing in the canon related world can compete.

This is a local photographer up in the northeast and he's gone all in on Fuji and doesn't regret it for wildlife.
His results with a TC are spectacular, before this I would not have recommended using a TC on any camera system unless you're desperate.

Media and Tear Sheets

Media and Tear Sheets

alanhewittphotography.co.uk

 

[soupdragon]

This might help with your semi-retired 7D/extender/100-400 in live view.
Save a lot of cash instead of a big lens.

 

[HoppyUK]

Interesting.

One other thing I've noticed is that the aperture can be used at it's widest, even at the long end of the lens, according to the display in the viewfinder, so effectively. Whether or not this actually physical or just electronic confusion within the combination, I'm not sure. I could always put it into aperture priority and change the aperture to test that one. If the exposure changes too, then the TC isn't affecting the aperture like it would on a native body/lens.

The loss of light with a teleconverter, raising the f/number, is optical and happens the moment the telecon is fitted regardless of what the camera thinks.

 

[sk66]

Lens *aperture* has no significant effect on a DSLR's phase detection autofocus as long as the focus point (objective area) can be seen... i.e. f/8 autofocus points at f/8. But if you are beyond that, there's little hope (my Nikons can achieve focus at f/11, and with focus points not rated for the aperture; in extremely limited situations w/ limited reliability)

A TC magnifies the image circle leaving the lens; this spreads the light out farther (loss of light), and increases the size of image blur points (increased diffraction/reduced DoF)... exactly the same as if the lens was originally a telephoto design of that FL/Ap.

Lens aperture always affects autofocus for on-sensor focus. The difference here is that the DSLR's dedicated AF system has its' own aperture limitation; which is typically much smaller than the lens's aperture (determines the amount of light and depth of focus at the AF sensor). But on-sensor AF does not have it's own aperture limit... so the lens' aperture determines the amount of light and depth of focus (focus tolerance) at the AF sensor (image sensor).

Another significant difference is that on-sensor AF is not capable of being "cross type" for increased sensitivity/accuracy... and it must revert to CDAF to finalize/maintain focus even if it has PDAF capabilities. This is because on-sensor PDAF is like split prism focusing... it uses 2 virtual-images (half the light) coming from opposite directions and compares them for position (phase) on the sensor. And once the image is in-focus, there are no longer two separate images on the sensor to compare.
That is significantly different from the way a dedicated PDAF system compares multiple separate real-images for phase (which always remain separate).

None of this is to say one choice is better/worse... partly because I have no idea what you want to achieve. But I can say that the more of a bodge it is, the less likely it will be successful.

 

[the black fox]

The in camera crop factor is no different to cropping in post. You are still loosing pixels.

Yea i had noticed how badly my image I.q had gone downhill since changing , only managed 3 shots on winter watch this year. And about 70 published shots in news media . . Dear oh dear perhaps I should buy a full frame camera again .. like hell I will !!!

 

[Dale.]

Thanks for the replies, it's been an eye opener so far. TCs really are quirky things.

Objectives are to get as much out of what I already own as I can. I was really suprised it all worked on the Fuji, via a Viltrox adapter too. That's a Fuji X-T10, Viltrox adapter, Canon 2x TC mkiii and the 100-400L and to a fashion at least, it all works, even though I have my doubts about the aperture, as that has to be physical. AF is slightly hit and miss but it's better than nothing and whilst I'm not convinced about the aperture settings, they appear to be changing when asked too, although I'm certain that it's f9 - f11, not the indicated, f4.5 - f5.6 which is native to that lens.

I really doubt I'll un-retire the 7D though, I never got on with it. When I bought my Fuji as a partial replacement, it was a breath of fresh air and I fell in love with photography again. I had a lot invested in Canon glass though and rather than invest in another system too, I bought the 5D, which I love.

The 600f4? I can dream but it would be an excellent addition to my kit but it's divorce territory. She loves me but maybe that's pushing it.

I would love to go Fuji, and run it along my 5D, I love the Fuji system and 3 years ago, it was a toss up between it and the 5D. I went 5D because of the glass I already owned and to be fair, whilst the Fuji has good image quality, in my opinion, it's not quite the same as full frame.

All the above mentioned and considered, this was just an experiment and I'm trying to understand the results of what I'm suprisingly seeing, so thanks for the replies on that. The combo may be pressed into service and used in anger soon, lockdown easing will help my plans and may be a while off yet. I can make the journey as part of my daily exercise on my pushbike as the location is close and remote too, hence the desire for extended reach and compact size.

It's all a bit Heath Robinson with lots of compromises in store I think but I will try it, nothing ventured, nothing gained. In my head, I may already know the outcome but my heart insists I try at least.

 

[ecoleman]

Yea i had noticed how badly my image I.q had gone downhill since changing , only managed 3 shots on winter watch this year. And about 70 published shots in news media . . Dear oh dear perhaps I should buy a full frame camera again .. like hell I will !!!

Oh dear, touchy much.

 

[the black fox]

Oh dear, touchy much.

yep most definetly . you must do really well with your gear 9000 views on flickr versus my 9,000.000 oops there I go again

 

[Bobsyeruncle]

another thread spoiled by pointless willy waving....

 

[ecoleman]

yep most definetly . you must do really well with your gear 9000 views on flickr versus my 9,000.000 oops there I go again

willy waving to the extreme. You’re not impressing me and I’m not in a competition. Grow up man you really are coming across as a bit of a knob.

 

[ancient_mariner]

although I'm certain that it's f9 - f11, not the indicated, f4.5 - f5.6 which is native to that lens.

It will be f9-f11 because although the lens is set to f4.5, the 2X TC will halve the effective aperture to f9.

 

[Dale.]

It will be f9-f11 because although the lens is set to f4.5, the 2X TC will halve the effective aperture to f9.

Yup, gotcha on that.

The combo will be having a run out on the weekend so we'll see how it performs. I'll have a better idea then on a future move, stick with it or go for a used Canon M5 or similar.