Motorsport Equipment Dilemma

captures.in.time

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I have the following cameras...

Canon 450d and a Canon 6d MkII

I generally use my 6d when I go out doing serious photography. I use the 450d as my second camera that always sits in the car and goes with me on family days out etc. Where I want a good camera but im not in full on photographer mode.

Recently I was at Knockhill shooting touring car racing using my 6d which is a full frame camera. I found my canon 70-300mm f4 L lens a bit short at times and a 400mm would have suited better. Unfortunately 400mm lens's are expensive and I can't use a canon teleconverter on the 70-300mm F4 L as they are just not compatible due to the back element clash.

So my question is... Am I better just sticking with the 6d MkII with its seriously fast rapid fire rate and then just cropping the images. Or am I better trying the much older and lower MP output 450d but getting the zoom advantage with the smaller sensor camera?

Obviously willing to just try it out and see... but some advice/ thoughts/ debate would be interesting to hear.

Thanks for reading!

Mark
 
Very few places need a 400mm lens at Knockhill, especially for cars!

Stick with your 6d.
 
Very few places need a 400mm lens at Knockhill, especially for cars!

Stick with your 6d.

Yes you are right there! Its mainly for front on shots of cars on two wheels at the chicane! Especially on reverse running days. It would even be useful at the hairpin on those days as your quite far up the back straight before the annoying chainlink fence stops.
 
The Kenko DGX pro teleconverter will work with the Canon 70-300L. I used to have both it does af slightly slower but you get 420mm.

Can I check as been doing a little reading and Kenko themselves seem to suggest the Autofocus only works with IS turned off and the lens set at f5.6 or faster.

I usually shoot in Aperture priority at about f8 for these sorta front on shots to get a bit DOF. When panning im less and wouldnt need the converter.

Can you tell me a little more of your experiences of how they work together. Im thinking of investing in one... but if the restrictions are too much i may not feel its worth it.

I am primarily a landscape photographer... but i do love the challenge thrill of motorsport and air shows too!
 
Can I check as been doing a little reading and Kenko themselves seem to suggest the Autofocus only works with IS turned off and the lens set at f5.6 or faster.

I usually shoot in Aperture priority at about f8 for these sorta front on shots to get a bit DOF. When panning im less and wouldnt need the converter.

Can you tell me a little more of your experiences of how they work together. Im thinking of investing in one... but if the restrictions are too much i may not feel its worth it.

I am primarily a landscape photographer... but i do love the challenge thrill of motorsport and air shows too!
I had that lens a long time ago but from memory IS did work, search the wed as I did before getting the TC for it.
 
Am I better just sticking with the 6d MkII with its seriously fast rapid fire rate and then just cropping the images. Or am I better trying the much older and lower MP output 450d but getting the zoom advantage with the smaller sensor camera?

Easiest way to tell which option gives you better results - shoot the same scene with both bodies then crop the FF images to match the crop body ones. Look at the results in the intended final product (30x20" print?) and decide which is better in your eyes. I would say the Steven above is probably right in that they'll be hard to tell apart (although the newer body will probably have better dynamic range and possibly better colour rendition/fidelity than the 450D).

Can I check as been doing a little reading and Kenko themselves seem to suggest the Autofocus only works with IS turned off and the lens set at f5.6 or faster.

I'm not sure you have it right in that the lens must be set to f/5.6 or faster. I would guess that the lens must be f/5.6 or faster wide open but can be set to whatever aperture you want to use (since most bodies use the widest possible aperture to achieve focus before stopping down to take the shot). No idea how the IS will be affected on Canon bodies - my 70-300 VR Nikkor's VR still works when it's mounted on a Kenko 1.5x telecon and the D750.)
 
Easiest way to tell which option gives you better results - shoot the same scene with both bodies then crop the FF images to match the crop body ones. Look at the results in the intended final product (30x20" print?) and decide which is better in your eyes. I would say the Steven above is probably right in that they'll be hard to tell apart (although the newer body will probably have better dynamic range and possibly better colour rendition/fidelity than the 450D).



I'm not sure you have it right in that the lens must be set to f/5.6 or faster. I would guess that the lens must be f/5.6 or faster wide open but can be set to whatever aperture you want to use (since most bodies use the widest possible aperture to achieve focus before stopping down to take the shot). No idea how the IS will be affected on Canon bodies - my 70-300 VR Nikkor's VR still works when it's mounted on a Kenko 1.5x telecon and the D750.)

See this link...

http://www.kenkoglobal.com/photo/lens_accessories/teleplus/check_program.html

This is what im on about... ur thoughts would be appreciated
 
See this link...

http://www.kenkoglobal.com/photo/lens_accessories/teleplus/check_program.html

This is what im on about... ur thoughts would be appreciated
The aperture you set and use has no bearing on the AF... when they refer to f5.6 that is the resulting wide open aperture with the converter in place.

So a lens with a maximum aperture of f4 will be f5.6 with a 1.4x converter/extender added, you can set a taking aperture of f8, f11 or even f32, they will have no effect on the AF performance...

Hope that makes sense...
 
The 70-300 f/4 doesn't seem to exist according to that link.

Most decent 2nd hand retailers offer a trial period so if you buy a telecon and it doesn't do what you want it to, you should be able to return it for a refund (but I'm not sure if the retailer has to refund postage or pay for the return postage.)
 
The aperture you set and use has no bearing on the AF... when they refer to f5.6 that is the resulting wide open aperture with the converter in place.

So a lens with a maximum aperture of f4 will be f5.6 with a 1.4x converter/extender added, you can set a taking aperture of f8, f11 or even f32, they will have no effect on the AF performance...

Hope that makes sense...

Ah!!! The penny has dropped! Makes sense!!! Thankyou!!!
 
The 70-300 f/4 doesn't seem to exist according to that link.

Most decent 2nd hand retailers offer a trial period so if you buy a telecon and it doesn't do what you want it to, you should be able to return it for a refund (but I'm not sure if the retailer has to refund postage or pay for the return postage.)

See the screenshot below

IMG_0477.jpg

Im still worried by that f5.6 comment even though i fully understand the post above
 
The aperture you set and use has no bearing on the AF... when they refer to f5.6 that is the resulting wide open aperture with the converter in place.

So a lens with a maximum aperture of f4 will be f5.6 with a 1.4x converter/extender added, you can set a taking aperture of f8, f11 or even f32, they will have no effect on the AF performance...

Hope that makes sense...
Well it did....

Although looking at the screenshot iv posted in the last post the wording of it still confuses me! The yellow warnings about AF
 
I use a Kenko 1.4x with my 70-300mm L on a Canon M5 and autofocus works fine.

Thanks! I take it you have some sorta mount adapter in the stack as well? That seems a heavy lens stack for a M series camera!
 
The 6D II will AF at f/8 max aperture using the center AF point only... which means AF is still possible using a 2x on your f/4 lens.

Id never thought about going for the x2. That would really up my range! Might have a look at them. It is generally centre point i use for that kind of shot! I take it no issues in AL Servo mode either rather than single shot?
 
The 6D II will AF at f/8 max aperture using the center AF point only... which means AF is still possible using a 2x on your f/4 lens.

I was always under the impression you used the slowest aperture of a lens when deciding on a teleconverter. As that is f/5.6 I don't think a 2x will autofocus at all. It certainly wouldn't when I tried a 2x on my 400mm f/5.6L
 
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I found my canon 70-300mm f4 L lens

See the screenshot below

The screenshot shows a Canon f/4-5.6 rather than an f/4 lens. The lens will be f/5.6 at the long end.

The 6D II will AF at f/8 max aperture using the center AF point only... which means AF is still possible using a 2x on your f/4 lens.

It's an f/5.6 lens at the long end so will be an effective maximum aperture of f/11 with a 2x converter. As the screenshot above points out, AF might be very dependent on conditions! (My Fuji X-T2 will AF the 100-400 XF OIS and a 2x telecon but slowly and only in good light. ALL functions of the lens [including the OIS] are retained. I would guess that for your intended use of head on shots of fast cars, the AF might be too compromised with the 1.4x let alone the 2x telecon.
 
I was always under the impression you used the slowest aperture of a lens when deciding on a teleconverter. As that is f/5.6 I don't think a 2x will autofocus at all. It certainly wouldn't when I tried a 2x on my 400mm f/5.6L
I think that error is my fault as I used the theoretical f4 to describe lens aperture performance with an extender, the 70-300L is indeed f5.6 at the long end and will not focus even with a 1 series body with a 2x but will AF with a 1.4.

The bigger question is... is it worth adding an extender or not? in these circumstances I think I would rather use the 450D and no extender rather than a 6DII with an extender...
 
I was always under the impression you used the slowest aperture of a lens when deciding on a teleconverter. As that is f/5.6 I don't think a 2x will autofocus at all. It certainly wouldn't when I tried a 2x on my 400mm f/5.6L
I just used the OP's description (f/4) because I'm a Nikon shooter. At the long end it would be f/11 and AF would be very questionable, but it might *function* in good light with strong contrast... I know my Nikons rated for f/8 will AF at f/11 max, but I wouldn't rely on it for sports/action.

What happens is that the tiny images used by the PDAF module get vignetted/masked by the aperture restriction. When they are masked out AF points are lost (or cross types convert to line type), and when vignetted they have a poorer image to work with.
 
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