5d mk iv - Problems setting the speed to faster than 1/200th using both Manual or TV when I have my speedlite attached. Totally confused as I can't figure out why I'd be limited to that or how to change it. I've looked at the manual and it's says High speed sync is possible but doesn't say how????

I was shooting a fashion show today indoors and really needed a faster speed for bits of it??

Any help would be appreciated :)


2 Answers 2


In short: don't go faster than 1/200

If your problem is a black band on your images (or overall darker images), you are reaching the sync speed of the 5D mark IV (see What is sync speed?). As 1/200 is the maximum sync speed of the Canon 5D IV (info from Canon), your frame won't be exposed correctly if you try going faster than 1/200. In short, the curtains of your body won't get fast enough.

Example from http://neilvn.com/tangents/high-speed-flash-sync: enter image description here

HSS (High Speed Sync) doesn't get rid of the problem but make the flash works in a different way, as you can see in this comparison (from http://neilvn.com/tangents/maximum-flash-sync-speed)

enter image description here

Now a short explanation (taken from http://neilvn.com/tangents/maximum-flash-sync-speed) of what exactly does HSS :

So with the older flash technology, flash is dissipated as that high-energy burst of light .. but camera manufacturers came up with the stunning adaptation of that technology, where they dissipate the energy from the flash as rapidly pulsed light. In effect, the flash now becomes continuous light over a very short period. The light from the flash is now dissipated even as the shutter curtains move across the frame. As that window between the two curtains move across the frame, the light from the camera’s speedlight is dissipated … exposing correctly for the entire frame. Remarkable technology!

But .. and yes, there is always a but … this comes at a price.

Instead of the energy from the flash being dissipated now as a high-energy burst, the light from the flash is now dissipated over a longer period. This means the effective power from our speedlights is reduced when we switch to high-speed sync mode, instead of the old-school way of triggering our flash as that high-energy burst of light.


Was having a blond moment. Within minutes of posting I realised I simple need to press the High Speed Sunc button, mad at myself now for not realising it at the time.

Any advice using this flash with the camera body would still be appreciated as I've only had it a week and I'm still learning

  • 1
    Hi Donna. Stack Exchange sites are not like other internet forums where a thread forms a discussion. This is a Question and Answer site. You can edit your question, or ask a new one. Only answers to the posted question should be posted in the answer area.
    – osullic
    Mar 5, 2017 at 20:15
  • 1
    Maybe see: How can I get started with a first flash gun? As osullic says, we're not a messageboard, we're a Q&A database. Searching that database should be your first step before asking any question. Please take time to read the tour if you plan to stick around and be part of the community vs. just milk us for info :). Also, it's very hard to tell you how to use a flash when you don't identify which flash you're using.
    – inkista
    Mar 5, 2017 at 21:32
  • Aye, very helpful. Cheers Mar 6, 2017 at 1:58

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