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Moving from Canon to Sony (1 Viewer)


Active member
I have the following set-up for bird photography:-
Canon EOS 1D MK IV
Canon EF 500mm f/4 MK 1 Lens
Canon 1.4 converter Mk 3
Gitzo G1325 Tripod
Wimberley Gimball Head MK 1
Lowepro Flipside 500 rucksack

I have been very pleased with the images and prints from the above combination. Due to getting older I find it harder to carry the equipment to and from the hides.

I am considering moving to a Sony A7R3 with the Sony 100-400 zoom lens with a Sony 1.4 converter.

I wonder if a bird from the Sony combination would have similar detail and quality when enlarged to an equivalent magnification to the bird from my Canon kit.

Dave Williams

Well-known member
Hi Cliff,
It really is a heavy kit you have at the moment in comparison to the Sony and a 100-400 I would be tempted too but those extra pixels probably need handling with care.

If finances are a consideration I would seriously look at the Canon 5D4 and the 100-400 Mk2.You wouldn't need to buy the TC as you have one. You could pick up this combination from Hdew for around £3200. Give me a shout and you can try mine.

Not sure where you could go to get a good price on the Sony kit, Digitalrev is HK based but reputable. The cost there would be £4300 but you would have a Canon TC to sell and off set the price too.

If money isn't a consideration the current lightweight set up for me to consider would be a Canon 5D4 with a 400F4 DO Mk2 and a 2x TC (when needed) I'm surprised you haven't already got the 2x as that would give you a lot of extra reach on your 500mm too.

If you go down the Canon route I would keep the 1D4 for a back up ( always handy to have one, especially one that can deliver higher fps than the 5D4) and sell the 500mm which should go some distance to financing the swop.

If you go the Sony route you don't have a back up body ( although I haven't a clue about their reliability) and might need more extras too such as new memory cards. Canon also provide their DPP for processing which may or may not be an advantage/saving.

My final thoughts are also about where you are going to use the kit and what you do with the images. If you travel abroad weight is crucial for carry-on luggage for flights. If you are most likely to be just taking the gear along the estuary footpath maybe a trolley would be a simple and cheap solution? I'm considering it anyway!


Well-known member
Anything that is a full frame sensor will have lenses that all weight about the same. So the sony 100-400 GM (1393g) vs canon 100-400 IS II (1550g) will all be about the same. (that said, the Sony 400mm f/2.8 is about 1kg under the current nikon/canon using 3 fluorite elements, though the new mk 3 canon is in the same ballpark).

The only way to significantly save weight is to go OM-D E-M1 mk 2 (574g) plus PL 100-400 (985g) or Oly 300 f/4 (1475g). The PL is 200mm - 800mm f/6.3 equivalent and the Oly is 600mm f/4 equivalent. The 300 f/4 can also take a 1.4x tc.

The E-m1 m2 has PDAF and is very responsive to subject tracking. It's an MFT sensor, so you won't be in the same ballpark as your 1D, but it's pretty good especially if you're not cropping much. And it is worlds lighter.

The other way is to step down to the Tamron 150-600mm G2 (2010g) vs your 500mm f/4 mk 1 (4015g). The Sigma 500mm f/4 is 3310g and very good IQ, but doesn't save even 1kg.



Well-known member
Just to follow up on my own post, I saw on canonrumors that a 500mm f/4 mk iii will happen next year. Maybe that will bring the price of the mk ii (3180g) down. Going from the mk 1 to mk 2 is almost 1 kg of weight savings. Though that is still twice the weight of the 100-400.

The 400mm f/4 DO (2090g) plus 1.4 TC (214g) is 2300g, squarely in the middle between the 100-400 and 500 mk2.


Well-known member
You already have an excellent kit so it will be hard to loose much weight without some sacrifices.
A 100-400/5.6 is a bit short IMO and adding a 1.4TC the bokeh will not be the same as with a longer lens either. ISO and AF will suffer a bit as well. Another factor is Sony ergonomics, rather small and fiddly controls, so try carefully before buying.
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Well-known member
To answer your initial question which I'm not sure was ever addressed - YES, the bird photos with the A7RIII and the 100-400mm GM lens will absolutely have the level of detail you are looking for from your current kit. The sensor is excellent, 42MP, and the lens is one of the best Sony has made, with very good resolving power even with the TC. The kit overall will be lighter too...though as others have mentioned, a full-frame mirrorless lens doesn't really save much weight over a DSLR lens - they both need to be large enough for the sensor...the much closer registration distance doesn't pay dividends when focal lengths get very long. The biggest advantage I find with mirrorless kits are that you can shoot the long lenses for birding when you want to, with some light weight savings, but can also save significant weight and size when shooting general purpose, scenic, walkaround, and travel photography with shorter lenses.

The A7RIII is capable of focus tracking and BIF shooting - I have several friends who shoot with that body very successfully - though it's not Sony's best tracking focus system and may be slightly behind the best pro-full-frame DSLR bodies. The A7III improved on focus tracking, and the A9 is the real flagship, but both use less dense 24MP sensors rather than the 42MP of the A7RIII.

You could also pick up a small APS-C body for pretty cheap, to shoot either alongside or instead of the full-frame body and use the same 100-400mm lens. I do a lot of birding with an A6300 APS-C body, paired with the 100-400mm GM lens and 1.4x teleconverter - I can get equivalent reach of 840mm plus very good continuous-focus tracking for BIF work. The 24MP APS-C sensor sort of offsets the 42MP full-frame sensor when you consider the crop - 400mm on 42MP full-frame cropped to match the framing of 400mm (600mm equivalent) on 24MP APS-C would be 18MP.

Ergonomics are a personal thing - you need to put hands on the cameras and really try to handle them for a bit to see if the ergonomics match well with you. Even full-frame bodies that have big grips have different designs and shapes and don't always fit comfortably to hand. And sometimes small bodies can fit nicely to hand - it all depends on your hands and how you adapt. I personally find Sony's ergo to be very comfortable and familiar - I've been using them a while, and have no issues holding, panning, and carrying them as the grips are deep enough to wrap my fingers and the bodies small and light enough when handing large lenses (which you typically hold and carry by the lens barrels or collar grips) to make panning and maneuvering quite easy, especially when shooting handheld and not on tripod.


Active member
:t:Thank you all for your excellent replies to my question, it’s a very difficult decision, I’ve been using Canon gear for over 30 years.

I do use DPP as my RAW converter, I would miss it.

I have used a trolley in the past when I took a spare camera body, lens and telescope to the Spinnies, but as most seem to have solid rubber tyres I’m a bit concerned whether the bumps might damage the IS mechanism of the lens. Eckla make a “beach rolly” which is available at Speed Graphics.

I do have a Canon extender 2X MK III but I have found the results a bit soft with the 500mm lens, maybe it’s my “Long Lens Technique”, so I did not list it.

The Sony combination sounds very attractive enabling me to save a lot of weight in my kit which would help my back a lot.

Thanks again all of you for your invaluable input.

Chosun Juan

Given to Fly
Australia - Aboriginal

To back up what others (particularly Justin and Vespo) have said, if you crunch the numbers, your thoughts about your current rig vs the proposed Sony rig (a7rm3 +100-400f5.6 x1.4TC) are pretty much in the ballpark - Yes you will end up with 16MP with a 35mm focal length equivalent of 910mm ..... the only difference will be that the max aperture will be f5.6 with your current rig, BUT only f8 with that Sony rig. This may in fact make a big difference to you, light wise hence shutter speeds. It may also provide lesser AF performance. The Sony rig you propose weighs 2.22kg (about 40%) versus the 5.33kg of your current set up.

Your rig will also have slightly (about a 1/3rd of a stop effectively, better bokeh). Even though the pixel pitch of the a7rm3 sensor is some ~20% less than your camera - though DR performance once the Sony is cropped looks pretty similar - maybe even slight advantage Sony. Put that down to a newer and more advanced sensor. You can check this out (and other possible body options such as the Sony a9, Nikon D500, or Olympus OM-D EM-1 m2, etc) at photons to photos here:

You could also check out the IQ using the sample tool at DPREVIEW where you can compare up to 4 cameras at various ISO settings.

I think the ultimate answer to your question (what rig to down weight to) lies with how much weight you are prepared to carry ? , and do the finances stretch to some of the lightweight developments on the near horizon?

Already announced is a Canon 600 f4L IS III at 3.05kg.
There is also a Sony 400 f2.8 GM at 2.895kg.

There are strong rumours that the Canon 500 f4L IS III is due to be announced in the 2nd half of next year. I would think they could get this down to around ~2.67kg.
There is also the Canon 600 f4 DO at around ~2.5kg or so possible after that - maybe even in time for the 2020 Tokyo Olympics.

Nikon has already released a PF (diffractive) 500 f5.6 at 1.46kg, and it is possible we will see the 600 f5.6 version at ~1.8kg maybe later next year? We can hope sanity prevails but expect ~4000 USD or more ....

It is also likely that Sony will release an a9m2 before the Olympics, and maybe even a matching 600 f4 GM which would also be around ~3kg. Both Nikon (certainly) and Canon will probably come out with FF Mirrorless a9(m2) competitors as far as bodies go. Expect to use adapted long lenses at this stage. Needless to say that all the Canon L IS III's and supertelephoto Sony GM glass are going to be "sell one of your children" expensive ! :eek!:

One of these new lightweight "big whites" will drop your weight by 30-40% (up to 2kg) when paired with a Sony a9, giving similar focal length and resolution with arguably slightly better IQ.

Otherwise apart from the rig you proposed (with it's f8 max aperture drawback) , I think there are 2 further realistic options (staying at f5.6 max) ....

(i) MFT Olympus OM-D EM-1 II with 300 f4 PRO + 1.4xTC for 840mm eq f5.6 . This rig is just over 2 kg, very slightly more resolution, similar DR and likely IQ than your current set up.

(ii) APS-C Nikon D500(S? by then) with PF 600 f5.6 (not officially announced yet - 2019?) for 900mm eq f5.6 . This rig will weigh ~2.66kg (exactly half the weight of your current rig), have a bit more resolution, similar or slightly better DR, and comparable IQ. I think this is the path I will take - at least until delicious 600 f4 Diffractive goodliness lands and I can evaluate whether the back and wallet ! can bear the weight ...... :)

Unless you want to outlay wads of cash for Uber light MkIII big whites, or really want to bleed for the Canon 600 f4 DO (and likely kiss one of the children goodbye :eek!: ) , then perhaps you are about to become a Nikon man ..... ??

Either the current Nikon D500 or D850 with either the current Nikon 200-500 f5.6 or the Tamron 150-600 f6.3 G2 will get you through (saving you 2.5kg to 1.75kg depending on your current rig, or ~50% to ~33% in weight) for now until the 600 PF lands .......

Over to you ..... :)

Chosun :gh:


Well-known member
Due to getting older I find it harder to carry the equipment to and from the hides.

Have you considered a hide clamp, to save weight? I've found it can work for me - when I visit a hide explicitly for watching waders. With a quick-release there remains some flexibility. That said, for my general walks I prefer to have a 1kg Sirui tripod + ballhead in my backpack.

In a dpreview post Danny Young (nzmacro) shows this photo illustrating his set-up: monopod + Gimbal head.

It's an annoyance that these hides don't come with inbuilt hide clamps. :-C
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