Flash Ratio 550EX / 420EX

[Vegas Poboy]

I was going over my manual and not sure if I missed it but does the flash ratio settings on the 550 work with the 420? The manual only says the 550.
I know that the 420 is firing but not sure of the end results.

[MediaMagic]

I was going over my manual and not sure if I missed it but does the flash ratio settings on the 550 work with the 420? The manual only says the 550.
I know that the 420 is firing but not sure of the end results.

I use ratio with the 550ex as master and 420ex as slave. Seems to work just fine most of the time. I do have some problems every once in a while that I think are caused by ETTL inaccuracies. I'm not sure how to correct those as there doesn't seem to be a consistent pattern, at least not that I have been able to track down as of yet.

[dtrayers]

I was getting frustrated with setting a ratio between the 550 and 420. I would crank it to the extremes and there wasn't any difference.

Then I realized that I hadn't set the 420 to be on group "B". :oops:

Make sure the 550 is on "A" and the 420 is on "B".

[caldgrp]

Are ratios affected by location of flashes? For example, I set a ratio on the ST-E2 of main to fill as 3:1. Assume while the main and fill are at different angles to the subject, they are both 4 feet away from the subject, I move the fill to 2 feet from the subject. Has the ratio of main to fill now changed or does ETTL decrease the fill flash output automatically to maintain the 3:1 ratio

[Vegas Poboy]

Thanks all for the replies, I'll make sure the 420 is on B the next time I'm setting up to play. Hopefully I can get this to work for about two more months then I'll start on my White-lightnings.

[scottbergerphoto]

Are ratios affected by location of flashes? For example, I set a ratio on the ST-E2 of main to fill as 3:1. Assume while the main and fill are at different angles to the subject, they are both 4 feet away from the subject, I move the fill to 2 feet from the subject. Has the ratio of main to fill now changed or does ETTL decrease the fill flash output automatically to maintain the 3:1 ratio
Each group will fire a pre flash prior to the actual flash. If you change the distance, the pre flash will pick the distance change up and compensate to maintain the ratio unless you go too close or too far, outisde the physical capabilities of the flash.
Regards,
Scott

[MediaMagic]

Hopefully I can get this to work for about two more months then I'll start on my White-lightnings.

Good luck with it. The Ratio feature is my very favorite feature of the EX series flashes. It can turn out some very nice results.

And btw... you'll love those White Lightnings... extremely well behaved and easily controlled monolights. There are more expensive "pro" brand lights out there, but, for portability, ease of use, great balanced color, durability, and cost to performance ratio, I really don't think there are any other lights out there that can hold a candle to the WL's.

[caldgrp]

Are ratios affected by location of flashes? For example, I set a ratio on the ST-E2 of main to fill as 3:1. Assume while the main and fill are at different angles to the subject, they are both 4 feet away from the subject, I move the fill to 2 feet from the subject. Has the ratio of main to fill now changed or does ETTL decrease the fill flash output automatically to maintain the 3:1 ratio
Each group will fire a pre flash prior to the actual flash. If you change the distance, the pre flash will pick the distance change up and compensate to maintain the ratio unless you go too close or too far, outisde the physical capabilities of the flash.
Regards,
Scott


Scott,

Thanks for the response. I kind of figured it worked as you described but it seemed counter-intuitive (too easy?) that the flashes distance to the subject was irrelevant, other than the physical limitations of the 420 and 550 EX's as you say.