Canon's 2x Teleconverter put to the test on the Canon 5D IV and Panasonic GH4
I've always been a fan of buying (or renting) the right lens for the job. I am also a stickler for buying the best quality glass I can afford. Because in the world of camera lenses, you really do get what you pay for. Check out our Canon 2X Extender Mark III Review.
Whilst this extender worked well, I sent it back to Amazon. Why? For me, the image quality didn't quite make the grade. Four + years down the line, I prefer the build in extenders on cameras like the GH5 and S1H.
Lens Glass Quality
I have taught many students that complain of their images not looking their best. However, when I place an L-series lens on their Canon camera, they are blown away by the difference. Not just in the increased sharpness but also by the colour change and improvement in bokeh (quality of blur).
Anyway, all of this has put me off buying a decent 2x Teleconverter (extender) in the past. I tried out a cheapie once and immediately laid it to rest on my bottom shelf as the image quality was appalling. Even with the Canon L glass on the end.
I checked out the Canon 2x Extender Mark II a few years ago but couldn't quite bring myself to take the plunge. So then I started researching the Mark III earlier this year.
I must say at this point that I was looking at this more from the point of video work than stills photography. Reducing light and increasing the chance of camera shake and blurred images doesn't have the same effect on video as it does in stills. This is because ordinarily, I would be using a shutter speed of 1/50th sec when shooting video. Motion blur is welcomed with most video!
Anyway, I figured that I would also use it for stills so I took the plunge and bought the Canon 2x Extender Mark III. These are my findings.
The Canon 2x Extender Mark III is as you would expect from Canon. White, sturdy, well built and fits like a glove. However, image quality is what counts.
Stills (Canon EOS 5D Mark IV Only)
Canon EOS 5D Mark IV Results
Note: All images taken on a tripod with no filters. Just the 70-200 @ 200mm and the Canon Extender Mark III
The Extender is fairly large so it adds a good amount of length to the Canon EF 70-200mm L 2.8 IS lens. Because of this, you should try to use a tripod whenever possible and when you do, attach the tripod mount to the lens and not the camera body to prevent damaging the lens contacts.
Canon 2x Extender Mark III - Autofocus
On the Canon EOS 5D Mark IV, the extender only uses the autofocus points on the central column. See image to the left. This is the same whether shooting at f5.6 or f22. Focussing was lightning fast and I couldn’t see any difference between focussing at f5.6 and f22 using the 5D Mark IV and EF70-200L 2.8 IS lens. Limiting but adequate.
It is worth researching to see if your Canon DSLR is capable of auto-focusing at smaller apertures with this extender before buying. However, the EF70-200L 2.8 IS on the 5D Mark IV works very well.
Apertures f5.6 and f8
The images here were pretty mushy and didn't respond well to sharpening. When you add sharpening to a mushy image, you tend to introduce those ugly "jaggies". You can't polish a turd as they say : )
F5.6 - "Standard" Conversion from RAW to JPEG with no editing (click for larger image)
F5.6 - "Fine Detail" Conversion from RAW to JPEG with no editing (click for larger image)
F8 - "Standard" Conversion from RAW to JPEG with no editing (click for larger image)
F8 - "Fine Detail" Conversion from RAW to JPEG with no editing (click for larger image)
Even though the images were a little soft, the quality was better and responded well to a touch of sharpening. I had to use a slightly higher ISO of 500 at this point. In fact, throughout the test, the ISO went from 160 at f5.6 to ISO 2000 at f22. This was to ensure I got a fast enough shutter speed, on the tripod, to prevent camera shake and blur.
F11 - "Standard" Conversion from RAW to JPEG with no editing (click for larger image)
F11 - "Fine Detail" Conversion from RAW to JPEG with no editing (click for larger image)
Getting better still and responding well to a touch of sharpening. The nice thing about the Canon 5D Mark IV's 30mp sensor is that you can add sharpening and then reduce the final output by a third. You still end up with a high resolution, sharp image that crushes the noise and any jaggies a little.
F16 - "Standard" Conversion from RAW to JPEG with no editing (click for larger image)
F16 - "Fine Detail" Conversion from RAW to JPEG with no editing (click for larger image)
There was a definite drop in quality here as possible diffraction started to creep in. Although I did have to increase the ISO from 1000 at f16 to ISO 2000 at f22 to account for the drop in light.
Saying that, I took a shot at f16, ISO 2500 and it is still cleaner than f22 at ISO 2000.
F22 - "Standard" Conversion from RAW to JPEG with no editing (click for larger image)
F22 - "Fine Detail" Conversion from RAW to JPEG with no editing (click for larger image)
In my experience and after shooting a fair amount of images on the 5D Mark IV using the Extender Mark III, only f11 and f16 were usable (possibly stock worthy) with f16 being the best.
Of course, you have to bear in mind that I was shooting subjects a fair distance away. At this focal length, I was sure to be magnifying slight atmospheric interference such as heat haze.
If you look at the following images, these were all taken from a much shorter distance to the subject and I was more than happy with the results.
Using the 5D Mark IV, I was able to autofocus easily at any aperture. This is great but when you are this distance away with such a long lens, focussing is almost as critical as when shooting macro. You need to be "on point" as it were.
For shooting subjects that are closer (such as birds from a hide), f11 and f16 work nicely but remember you will almost certainly need to use a higher ISO. This means that older cameras or cameras with smaller sensors may get a lot more noise.
The bird shots above had ISO's ranging from ISO 800 to ISO 4000.
Video (Canon EOS 5D Mark IV and Panasonic GH4)
I have added all my findings and thoughts below after the video. Hopefully you will gain some insight into the quality of the Canon 2x Extender Mark III enough to make a good purchase decision. I wouldn't expect it to work as well with cheaper or older Canons but check out how it performs with the 5D IV and GH4.
As I have previously mentioned, I intend to use the Canon 2x Extender Mark III mainly for video. Because of this, I was keen to see the results at 4K from these cameras. I will be getting the Panasonic GH5 soon which has no low pass filter so I am expecting great things from that camera.
I'll add those results as and when I get my grubby little paws on it!
EDIT: Review now in, see link above.
5D Mark IV (Equivalent of a 696mm lens set up at 4K)
So, putting the awful MJPEG codec to one side (Canon have a firmware update coming soon which I hope addresses this issue), how did the 5D Mark IV do with this set up at 4K? All clips are straight from camera with no sharpening or filters used.
Note: Always turn off image stabilisation when locked down on a tripod. When turned on, the lens will try and stabilize itself actually causing the footage to "wobble". Also, at this focus length, the jello is terrible so don't even think about panning...
Not really good at all. The footage looks as though I have used a soft focus filter and any sharpening wouldn't do it much good. I don't think this is usable.
A little better at f8 but still rather soft. Maybe a touch of sharpening would help but I wouldn't film anything at this aperture/lens set up unless I absolutely had to.
Much better now and definitely usable. Sharpening would increase the quality too. I would be ok filming with this for certain events.
Very similar to f11 with not much difference to see overall...
Lost a fraction of image quality at f22 to my eye so probably wouldn't use this setting for filming.
It seems to me that the only two really decent apertures to film at 4K with are f11 and f16. Both produce sharp footage that will no doubt be improved further with a touch of sharpening in edit.
In all honesty, I didn't buy the 5D Mark IV for video (only now and again shots as B roll) but for stills and when I saw the difference with the GH4, I will definitely stick with that (and the GH5 when it arrives) for filming.
GH4 (Equivalent of a 653mm lens set up at 4K)
This camera is awesome for video and that is why I bought it. The 4K footage is outstanding and when output to Pro Res HQ 4:2:2 10-bit through the Atomos Ninja Flame, it really is professional quality footage.
The bonus is that by using the Metabones Speedbooster, I not only claw back a little of the crop factor but I also gain a stop of light. This means the widest aperture I got from the 70-200mm/Extender Mark III combo was f4!
Another thing I noticed was that the rolling shutter was barely noticeable at this focal length...
It didn't look so good "in the field". However, when I got this clip on the timeline, I was surprised to see that the quality was actually better than the 5D Mark IV at f5.6! Even though it is slightly soft, with a bit of TLC it could probably be quite usable especially when filming closer objects (no atmospheric "disturbance").
Definitely usable with the correct exposure (oops) and a touch of editing but overall, impressive straight from camera.
Now we're talking. I would happily shoot all day long with this set up and aperture and I know that the final edit from this clip would look great. Happy days.
A touch better than f8.
Great stuff and sharper still I think. You will see in the video at the end, a series of clips all shot at f16 on the GH4 with this lens configuration and to my eyes (and screen), the footage looks great.
Again, a definite drop in image quality to the point where I would never film with this aperture.
I have to say that from this Micro Four Thirds sensor, I was mightily impressed by the GH4 and the quality of footage I got compared to Canon's much larger sensor.
If you think about it, the light had to travel through the 70-200mm lens, through the 2x Extender and then through the Metabones Speedbooster. That is a lot of glass but I am loving the footage from it.
I feel that buying the Canon Extender Mark III was a good choice as I will be using it mainly for video.
However, I am also pleased with the performance for stills on the 5D Mark IV but only at apertures of f11 and f16.
I think I will do some more tests to see if I can get better results from other apertures but for now, I will stick with f11 and f16 for stills and not use it for video on the 5D Mark IV.
As for the Panny GH4, I am a happy camper. This will definitely be used this a fair bit for wildlife and sports and look forward to the next beach motocross here in Weymouth! I would happily use this set up with apertures between f5.6 and f16. These give me more flexibility but I may need an ND or polariser filter at wider apertures.
I cannot wait to get this lens set up on the GH5 because with a larger (in megapixel terms), higher quality sensor, no crop and no low pass filter, I am expecting big things.
So, my business has the Canon EOS 5D Mark II and IV for stills. The Panasonic GH4/GH5 at 4k, Pro Res, 10-bit, 4:2:2 for video...perfick!