Custom function setting on 600 EX RT with external battery pack

[iND]

 When using external battery pack with the 600 EX RT you will get better performance from the internal AA’s in the flash if you set Custom Function #12 on the flash to “ 1 “.

This will segregate the AA's from the recharge circuit when it is turned on.

The way that flashes are usually made is that they devote about 10% of the recycle to the flash when an external power source is connected.

This new Custom Function on the 600EX-RT overrides that when it is turned on.

[p4pictures]

C.Fn 12 is also in the 580EXII & 580EX plus I think the 550EX too, maybe even the macro flashes.

If all out fastest recycle speed is the aim, leave this set to 0, the flash will charge from the 8 AA's in the pack and the 4 AA's in the flash, however when they run out you have to change batteries.

If you set this to 1 then the flash charges from the 8 AA's in the pack only, the 4 in the flash run the display & electronics. What this means is that when the external pack is dead you can unplug it and get an assistant to swap out the cells, but you will still have 4 working AA's in the flash in case you need to react quickly. Personally I tend to use it this way as it's better for me to be able to react to a picture rather than have the absolute fastest recycle times. Though from 8 AA's the receycle is pretty fast.

Brian

[VCase]

Do you have to make changes to anything on your camera to use the battery pack? Or once you've used C.Fn 12 and set it to 1, you're good to go? I noticed on my camera I could do just about the same thing on my camera.

Also, once these changes are made, do I have to switch it back when I am NOT using the battery pack?

How do I know that the battery pack is being used instead of just the batteries in the flash itself? The image of the flash that shows when I turn it on isn't the image of the flash with the battery pack like it appears when looking at the C.Fn 12 area. Thanks for the info.

[Waddizzle]

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@VCase wrote:
Do you have to make changes to anything on your camera to use the battery pack? Or once you've used C.Fn 12 and set it to 1, you're good to go? I noticed on my camera I could do just about the same thing on my camera.

Also, once these changes are made, do I have to switch it back when I am NOT using the battery pack?

How do I know that the battery pack is being used instead of just the batteries in the flash itself? The image of the flash that shows when I turn it on isn't the image of the flash with the battery pack like it appears when looking at the C.Fn 12 area. Thanks for the info.

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