rmalarz Loc: Tempe, Arizona

The only features that matter to me are, lens quality and aperture accuracy, as well as accuracy in ISO and shutter settings. The rest is fluff. YMMV.
--Bob

mwsilvers Loc: Central New Jersey

Why do you want a new camera? Are you not happy with your current images? What improvements are you looking for? As has been suggested, you may get more bang for your buck with a new lens.

SIMIBILL

I also have an 80 D. I shoot events for my Elks Lodge, and Landscapes, Seascapes, Sunsets, Sea Mamals, Birds, etc. I live in Santa Barbara, California, so there is an endless variety to shoot outdoors. Also indoors at Elks events, etc.
What is your opinion of giving in to my burning desire to buy an R5 and 100-400 2.8 Canon lens?

CHG_CANON Loc: the Windy City

The EOS R5 has redefined the full-frame mirrorless market, a 45MP wonder. Alas, there are no 100-400mm f/2.8 lenses. Possibly, you mean the redesigned 70-200 f/2.8 zoom or the 100-500 variable aperture zoom?

That's a lot of money to invest into Canon's best higher pixel-density full-frame camera, and with the 100-500L zoom, a premier kit for all shooting situations and especially high-action wildlife.

In this thread, or another recent and similar, the issue was raise of your computing power, as these 45MP files will double what you're processing now from the EOS 80D.

All that said, your EOS 80D is no slouch and you very likely have not exhausted this camera for all the various topics you've listed. If you have an EF or 3rd-party lens that already puts you at 400mm or longer, there's no valid reason to jump from 'great' to 'the best'. Unless, this next camera really is intended to be your last, like 12+ years minimum. Your EOS 80D should deliver a full 10-years shooting life, at an industry standard 24MP resolution. You can save a lot of money looking closer at your EF / EF-S lenses and seeing where / if updates are needed to maximize the 80D body for its full useful life.

josquin1 Loc: Massachusetts

I've owned both Crop and full frame cameras and I have not really seen a difference in the quality of the images. The 80D is a wonderful camera.

revhen Loc: By the beautiful Hudson

Now, just do you want to change? Are you dissatisfied with the results you are getting? If so, would it be the body or the lenses? What cameras have you discovered would solve these problems?

SIMIBILL

The lens I meant is the Canon 100-400 4.5-5.6 L lens.
I am almost 79 years old and have had the 80D for 4 years or more. If I buy a new camera it will most likely be my last one. The lens I use most now is a Tamron 18-400. Mediocre, but good for a non-canon lens. Do you think
a Canon, L lens will make a significant difference on the 80D?

CHG_CANON Loc: the Windy City

Most Canon L-series lenses are large and heavy, built with metal for 'forever' usage in all possible situations. They feature great optics too, but many options exist for excellent optics without the same heavy build. Only you can decide if the added weight / size / cost is worth changing away from the Tamron. That's the type of investigation you can achieve from an outfit like LensRentals.com, say for a week-long rental and shooting.

raymondh Loc: Walker, MI

Along this upgrading theme, I’m wondering if Canon users who’ve used both, find that the 5DIV has any significant advantage over the 5DIII.

CHG_CANON Loc: the Windy City

It adds more pixels resolution, not much else. The 5DIV AF algorithms pick-up the next round of changes that went into the 1DXIII, but the camera was already great with the 5DIII / 1DXII capabilities. There's a lot more 'gain' in the EOS R5, adding eye tracking into the AF capabilities, along with another large jump in pixels, and IBIS.