Hey! I totally feel u on this. Honestly, I've been using Godox gear on my 5D IV for a couple years and it's been a total beast for weddings. For your situation, here's what I recommend: - Godox V1-C Flash for Canon: The round head gives such a nice natural falloff and the HSS is super reliable.
- Godox V860III-C Flash for Canon: Amazing value and the recycle time is insanely fast with those li-ion batteries... literally no more waiting for AAs to charge during the cake cutting lol. I mean, the Canon Speedlite 600EX II-RT is great, but for the price of one Canon, u can get like three Godox units and a trigger. It's a no brainer imo! I havent had any communication issues as long as the foot is locked in tight. Are u planning on doing much off-camera stuff too?

Honestly, I've used the Canon Speedlite 600EX II-RT for ages but the value is disappointing lately. For your 5D IV, check out the Westcott FJ80 II M Universal Speedlight. It handles HSS and recycle times way better. Unfortunately, I had too many communication errors with cheap generic stuff on my 5D IV hot shoe... its honestly a nightmare. I guess build quality just isn't what it used to be. Hope that helps!

Coming back to this - honestly, before you drop serious cash on a new unit, you might want to look at some DIY maintenance on your 5D IV body first. Those communication errors you're hearing about are pretty much always due to the hot shoe plate loosening up over time - it's a known thing with the older EF bodies after a few years of heavy wedding use. - **Tighten the hot shoe plate:** If you peel back the little spring plate with a needle, there are four tiny Phillips screws. Snugging those up yourself saves you a $200 trip to a professional service center and usually fixes the E-TTL and HSS flickering instantly. - **Go for a "repairable" beast:** If your looking for a new flash that handles heavy sessions, I'd suggest the Nissin MG80 Pro. It's built like a tank and uses a quartz flash tube that doesn't overheat nearly as fast as the standard glass ones. Basically, it's designed for people who actually want to maintain their gear rather than just tossing it when the tube pops. So basically, a little self-service goes a long way with the 5D IV. It's a pretty easy fix if you have a precision screwdriver kit.

I've spent way too many hours lately just deep-diving into the market shifts for EF mount gear. Tbh, it feels like the whole landscape has changed since the 5D IV was the king of the hill. I remember when it was basically Canon or nothing if you wanted reliability, but I think the gap is closing fast. I was reading somewhere—not sure if it was a forum or a tech blog—that the communication errors people see are sometimes down to the pin alignment on the hot shoe being slightly different on the older 5D bodies compared to the newer mirrorless ones. IIRC, some brands actually had to issue firmware updates just for the Mark IV specifically. Honestly, it’s a tough call because the market is so flooded right now. When I was looking for my own kit, I found that the "third-party" stigma is mostly gone for professional work, but there's still that nagging doubt about long-term durability compared to the native gear. I mean, the price difference is MASSIVE nowadays, which makes you wonder where they're cutting corners. I haven't quite decided if the premium for the name brand is still worth it in 2024, but the research is definitely a rabbit hole!

It sounds like the consensus so far is leaning towards Godox for the fast lithium recycle times or Westcott for better build, plus that great tip about tightening the hot shoe screws yourself to avoid communication errors. Since you mentioned the price of new Canon gear is a bit much, honestly, the smartest move for long-term value is hitting the used market. Because so many pros are jumping to mirrorless right now, you can find the original Canon Speedlite 600EX-RT for a total steal. It is a complete tank and has much better weather sealing than the budget brands. If you really want brand new gear but need to keep costs down, here are two practical options that work great with the 5D IV:

• Yongnuo YN600EX-RT II: It is basically a clone of the Canon system and integrates perfectly with their existing radio triggers for a fraction of the price.
• Godox TT685II-C: If you dont mind using AA batteries instead of the proprietary lithium packs, this does everything the V-series does but is much easier on the wallet. Tbh, I have found that buying used flagship gear is usually better than buying cheap new stuff. It might be older tech, but it was built specifically for the 5D IV workflow from day one.

Interested in this too

Man I wish I found this thread sooner. Would have saved me so much hassle.

> For those of you still rocking the 5D Mark IV, what flash are you currently using and why? Is the brand-name Canon gear worth the extra investment? im so happy i finally found this thread tho. been dealing with the exact same problem for months now with zero luck. honestly it is so frustrating trying to find a flash that actually works well and doesnt feel like a risk to the body. i am still totally stuck. basically havent found a clear answer yet... kinda too cautious to pull the trigger on something third party but the native prices are wild. glad im not the only one struggling and if i find anything that actually works ill definitely let you know.

Would love to know this too