TriX Loc: Raleigh, NC

But counterbalanced by 1-1/2 stops better DR and 1-1/2 to 2 stops better low light high ISO performance of a similar weight APS-C (with higher resolution). There is no free lunch, only compromise.

gouldopfl

You can use EF lenses on a RF camera. The adapter was a bit over engineered and some of my EF lenses work better using the adapter. The price of the new Canon lenses for someone that is a hobbyist, now retires and not having the income I did have, makes this a easy way to go. I did purchase the RF 50 mm f/1.8 and compared it to my EF 50 f/1.8 and there was so little difference that I sent the RF lens back. The RF version doesn't have a manual/auto switch on it.

Hip Coyote

The answer to the question is that changing to Sony FF will not save you weight. The answer to your unstated problem is that you might want to consider micro 4/3 gear. I looked at some of your posted photos. M43 will serve you well. Photos of backyard stuff, flowers, pets all can be easily captured on m43 gear. I use it and it’s ok for my purposes. Want to spend money and have a interchangeable lens system? Look at Oly or Pany m43. Or downsize a lot to s Sony rx100 or similar. Otherwise you’re wasting $$$$.

Hip Coyote

I have that lens. It’s kinda heavy. But maybe then75-300 might be ok. Much lighter.

amfoto1 Loc: San Jose, Calif. USA

You will be disappointed.

Not that Sony gear is bad in any way. In fact it's good.

But you won't reduce the weight of your kit by making that switch. In fact, you'll be making your kit heavier.

The Sony camera most comparable to the R5 is the A7R IIIA.

The R5 weighs 26 ounces. The A7R IIIA weighs 23 ounces. So you would save 3 ounces with the switch of camera.

The Canon RF 100-500mm weighs 48 oz. The Sony 200-600mm 75 oz. So you would ADD 27 oz to your kit with the switch of lens.

Make that switch and you will end up with a 24 oz. HEAVIER kit of gear.

If you are serious about reducing weight, the best way to do so would be to switch to a crop sensor camera, which in turn would allow you to use smaller, lighter lenses.

For example, with Canon R7 there would only be modest weigh savings from the camera alone (4.5 oz. less than R5)... But you also could switch to the RF 100-400mm lens. On the APS-C format camera, that lens will "act like" a 160-640mm would on full frame. And at 22.5 oz. the RF 100-400mm is less than half the weight of the RF 100-500mm (48 oz.)

An R7 with the RF 100-400mm would save close to 2 lbs (about 30 oz.) weight compared to your current rig. Plus you get "perceived" additional telephoto reach of an additional 140mm.

You could build similarly lightened kits with APS-C Sony, Fuji or Nikon cameras, or possibly even a little lighter with Panasonic or OM micro 4/3 system cameras and lenses.

But it may make more sense to stick with Canon, keep the R5 for when you want full frame (ideal with short focal lengths, for example), be able to use other accessories you already have (batteries, chargers, other lenses, flash, etc.)

61jhawk Loc: Tarrant County, Texas

When I reached 83 I decided that I needed a midweight bridge camera to carry around. I had a Nikon D7100 and a D500 along with a nice assortment of Nikkor lenses including a 70-200 and 200-500 but they were getting heavy to lug around for every day use. I kept all the lenses, the D500 and sold the D7100 and bought a Sony RX10 model IV. It is easy for me to carry around and shoot and I still have the Nikon D500 and lenses for when I want to use the big stuff for a planned shoot. It's working out well for me to use both types of setups.

gwilliams6

The OP mentioned the Sony 200-600mm lens in his original post, did you miss that, LOL.

I spoke to both the weight savings in some fullframe Sony models over the Canon R5 which is real. And I also said in one comment that there could be more weight savings in APS-C from Sony and other brands as well as Micro 4/3rds.

But I also recommended the OP look at the superb Sony Bridge camera RX10 IV which has a 25X, equivalent 24mm to 600mm Zeiss zoom lens and has a stacked sensor for 24fps stills and up to 960 fps in video. That Sony RX10 IV also has weight savings over the OP's current camera-long lens setup, and has a longer reach out to 600mm.
https://www.sony.com/ke/electronics/cyber-shot-compact-cameras/dsc-rx10m4

Facts are always what matters to me, so let the facts guide the OP to make the right choice for their needs.

Cheers and best to you all, even you diehard Canon fanboys, LOL

(Download)

imagemeister Loc: mid east Florida

There is NO similar weight APS-C ! ........and, yes, there is no free lunch - that is why I qualify my statements by saying if you are SERIOUS about weight/size

imagemeister Loc: mid east Florida

The RF 100-400 is a serious compromise IQ for size/weight and price - it is CHEAP for a reason - and, Yes, I have seen the Imatest numbers.

imagemeister Loc: mid east Florida

The only thing in Canon I could recommend would be a R10 with the EF adapter and Tamron 100-400. The Tamron is a SHARP f6.3 lens - not f8 like the Canon.and very light - not sure but it might even work with an EF 1.4X TC on the R10.

TriX Loc: Raleigh, NC

Yes, there is. The 32.5 MP Canon R7 (vs 21MP for the RX10) plus the RF 100-400 weighs 2.6 lbs vs 2.4 for the RX10 MK 4. You get the same 600mm (a stop slower), BUT you get 1-1/2 stops better DR and 1-1/2 stops better high ISO performance which more than negates the 1 stop difference in max aperture (and who shoots at F4 at 600 mm anyway with a 1” DOF?), dual card slots instead of 1 and twice the FPS. I can make the same argument with a Fuji X-T4/T5+ the 70-300.

Not saying the RX10is anything other than a great camera, but in terms of performance it’s no match for an APS-C sensor - size does matter.

TriX Loc: Raleigh, NC

And you’d be giving up the image stabilization of the R7.

And I’ll put my Fuji APC body and lens IQ up against the RX10 any day. How about we also try some ISO 6400 (or higher) or high DR scenes? Arguing that very small sensors are the equivalent of larger sensors in terms of performance for equivalent technology is a no win argument. I get that you love your RX10 - it’s a fine camera, but there ARE compromises in very small sensors that are just undeniable.

imagemeister Loc: mid east Florida

Just to be clear, the pixel density of the RX is greater than the R7 ......and the f-stop of the Canon lens @400mm is 8 - so, that is a 2 STOP difference .......I shoot at 600mm f4 almost ALWAYS with the RX - really no good reason NOT to. Yes, size of the sensor does matter - but where weight is concerned - size of the lens matters - that is where the weight is !

"and twice the FPS." - FYI, the RX does 24 FPS and R7 does 30 - unless you are talking about the R7vsR10 - but that has nothing to do with this thread or OP.

imagemeister Loc: mid east Florida

I never said small sensors are equal to larger sensors - where did I say that ?? LOL

imagemeister Loc: mid east Florida

2.6 lbs. is NOT the same as 2.4 ....similar maybe