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01-24-2018, 03:54 PM   #16
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Nigel - Thank you forthe great write-up. I would assume that the intention of the Radio ID function is to isolate your flash setup should you find yourself set up beside one or more other flash setups operating in the 2.4 G Hz band.


Last edited by jbinpg; 01-24-2018 at 04:02 PM.
01-24-2018, 04:27 PM   #17
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Glad you saw it! I'm not sure if this will convert me from being "P-TTL Man" into being "Cactus Man" ...(well, "Vice Cactus Man" after ClassA of course!) ...."Acon Man" seems to have become a vacant position now, unless Clackers has already been appointed

The Radio ID does seem superfluous, considering that there are also 16 channels .....
01-25-2018, 04:05 AM   #18
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QuoteOriginally posted by mcgregni Quote
The Radio ID does seem superfluous, considering that there are also 16 channels ...
That's my view as well.

The purpose of the radio ID feature is to avoid interference with other photographers using Cactus equipment as well. However, using a different radio channel is a better solution because one not only avoids interference but also radio packets clashing with each other. Two photographers using different channels (say one using "1" and the other "13") should be able to work in parallel without radio packets ever clashing. If both use the same radio channel then there is at least a remote chance that their radio packets clash and misfiring or other problems occur.

The Cactus manual does not really explain why the "Radio ID" feature is there in the first place and I had to think very long and very hard to come up with one justification: Imagine you arrive at a scene (say a wedding) and another photographer happens to use Cactus equipment as well, configured to the same radio channel as you use. In this case, you'd have to go through all your devices and change the radio channel.

If you choose a creative radio ID then the chance that someone else will use the same radio ID is lower (1/10000 vs 1/16), i.e. you reduce your risk by a factor of 625 and it becomes very unlikely that you'll ever have to reconfigure all of your devices.

Another, very implausible, AFAIC, justification could be that you really want to work with a particular radio channel (say all others are heavily compromised) but someone else is using that channel already.

Overall, I'd say there is precious little justification for a "radio ID" feature.

Last edited by Class A; 01-26-2018 at 02:56 AM.

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