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by Alan Murphy on Sun Feb 12, 2017 9:26 am
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John, I have had the exact problem a few times, and every time it was not the flash duration or the flashes themselves, but the wireless receivers that trigger the flashes.. Once I went back to using cables, the problem went away, regardless of using different flashes or power.
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by neverspook on Sun Feb 12, 2017 1:38 pm
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Greg Downing wrote:
neverspook wrote:
E.J. Peiker wrote:
neverspook wrote:
Greg Downing wrote:Do note that adding a 4th flash to a 3-flash set up will gain you exactly and only 1/3 of one stop of additional light - which is negligible.... You would have to go from 3 flashes to 6 flashes just to gain one stop of light. You should get no ghosting at all when shooting at 1/16 or 1/32 power (if there is no ambient present) even if the bird is doing summersaults.
That's interesting, Greg. I am having trouble figuring out why an extra flash would only provide 1/3 stop of additional light. Can you explain?

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If you have three flashes on the subject each one represents 1/3 of the illumination,  Adding another one adds an equivalent amount of light as each of those three (assuming they are placed at the same distance, so that would be the equivalent of another 1/3 compared to the original 3 flash set-up.  Alternately, if you have 4 flashes at equal distances, each one provides 1/4 of the light - it's just a matter of perspective :) 
Sure, it would add 1/3 of the illumination, but is 1/3 of the illumination equivalent to 1/3 stop?
Yes - 1 stop is always double or half whether it be aperture, shutter speed or flash output. So if you have 3 flashes and you need to double the amount of light for one stop you need another 3 flashes at the same power to add one stop, with each flash providing 1/3 of that full stop. 
Right, of course. Thanks. I must have been having a "duh" moment.
 

by john on Sun Feb 12, 2017 6:54 pm
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Greg Downing wrote:John,

It's hard to say if it's ambient light or not but one thing to check is to take a shot without flash with the bird in the target zone and see if you get anything registering. If you do then you will get ghosting. You cannot have sun shining on the bird.

Thanks Greg....I tried this today and for the most part it works to get good images, but whenever one of the hummingbirds does a major power turn I'm still getting a bit of ghosting.  I can live with the keeper rate I'm getting for this trip but will sort this out before I go again.  I was down to  100 Iso F16 and  1/64 at one point.  I guess even though I'm in the shade the ambient light from the bright sunlight changes enough to infiltrate my setup on occasion and the flash setup isn't enough to overcome that.  Thanks for all the help everyone...I'm not going home empty handed. :)  I'll post another example once  I get some downloading and processing done.


Last edited by john on Sun Feb 12, 2017 7:57 pm, edited 1 time in total.
 

by john on Sun Feb 12, 2017 7:05 pm
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Alan Murphy wrote:John, I have had the exact problem a few times, and every time it was not the flash duration or the flashes themselves, but the wireless receivers that trigger the flashes.. Once I went back to using cables, the problem went away, regardless of using different flashes or power.
Thanks Allen....I missed your post  Will give it a try once I get home.
 

by SantaFeJoe on Sun Feb 12, 2017 8:21 pm
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Here's a similar thread:

viewtopic.php?f=1&t=235083
Learn the rules like a pro, so you can break them like an artist.  -Pablo Picasso
 

by john on Sun Feb 12, 2017 9:37 pm
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SantaFeJoe wrote:Here's a similar thread:

viewtopic.php?f=1&t=235083
Thanks SFJ!  That was helpful.  I guess I should have done a better  search.
 

by john on Wed Feb 22, 2017 2:03 pm
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Although my keeper rate improved with the help in this thread, I'm still not happy with the results. I can't seem to find any information online to as to how to wire things up and I'm not generally a flash user and not up on wiring and such so if anyone has any  direction  I'm all ears.  I'm trying to keep this as inexpensive as possible as this in something I only get to do on rare occasion.  For what its worth I'm using the ebay 433mHz i shoot trigger and receivers.

I was contemplating using the transmitter to fire the first flash via radio signal, and then using a splitter hub (apparently stereo or mono cables are interchangeable for this application) on the receiver to wire up the remaining flashes via hot shoe adapters with female 3.5mm jacks but don't know if that's feasible.  Would one receiver put out enough power to trigger 4 more flashes?  Or is there a better way to wire things up.
 

by john on Wed Feb 22, 2017 5:57 pm
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To answer my own question....I think this will work just great.  I conducted the alligator clip/banana/apple test and one i shoot receiver triggered a split 3.5mm stereo jack with 2 flashes just fine so I see no reason this hub would not work to trigger 4 flashes.  I'll leave it up in case anyone else wants to follow my crazy ( at your own risk of course :) )
 

by SantaFeJoe on Thu Feb 23, 2017 8:49 pm
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This is an antiquated system now, but used to work and still may if you can find the parts. I would consult Nikon before using it with current flashes and cameras. The cube is an AS-10. It has three sockets for cords and the flash mount on top. One is used for an input and two for outputs. It also has a tripod socket on the bottom. It is used with an off camera flash cord e.g. SC-17, 28 or 29. They can be extended with other cords (SC-18 or 19) and attached to additional AS-10s as shown. The cords come or came in different lengths. If I remember correctly, there was a certain limit on the number of flashes (6 or 8?) and a total of 33 feet cord length. I have not used it in years, and then it was sparingly, but it was a very efficient system. It is not inexpensive, I'm sure. Nikon has discontinued the AS-10 now. You can probably hook it up without the AS-10 if the flashes have sockets for a cord.
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by john on Thu Feb 23, 2017 9:13 pm
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Joe...thanks for you're input.  That looks like it would work well. I have ordered some off camera flash hot shoes but couldn't find any with 2 -3.5 mm females so ended up getting ones with one PC and one 3.5  mm female, so if one of the hot shoes decides to quit I can still tether the flash via the PC connection.  I've decided to not tether to the camera at this point as it seemed to work fine triggering the first flash remotely and tethering the 4 flashes from the spliter hub.  Whether that solves the flash inconsistency remains to be seen but I won't know until I can get back to some place with hummingbirds hopefully this summer. If not I can always tether back to the camera hot shoe as you have done.  Thanks again for your input.  It was disappointing getting lots of really nice poses with ghosting so I'm hoping this solves that problem,  

On another note,,,
The triggers I have are 433 mHz and I noticed the more costly ones are 2.4 gHz.  I wonder if that frequency gives a more consistent trigger or if it just increased range?
 

by E.J. Peiker on Fri Feb 24, 2017 9:41 am
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john wrote:Joe...thanks for you're input.  That looks like it would work well. I have ordered some off camera flash hot shoes but couldn't find any with 2 -3.5 mm females so ended up getting ones with one PC and one 3.5  mm female, so if one of the hot shoes decides to quit I can still tether the flash via the PC connection.  I've decided to not tether to the camera at this point as it seemed to work fine triggering the first flash remotely and tethering the 4 flashes from the spliter hub.  Whether that solves the flash inconsistency remains to be seen but I won't know until I can get back to some place with hummingbirds hopefully this summer. If not I can always tether back to the camera hot shoe as you have done.  Thanks again for your input.  It was disappointing getting lots of really nice poses with ghosting so I'm hoping this solves that problem,  

On another note,,,
The triggers I have are 433 mHz and I noticed the more costly ones are 2.4 gHz.  I wonder if that frequency gives a more consistent trigger or if it just increased range?
433MHz not 433 mHz (Megahertz not Millihertz ;) ) - the difference is range.  A 2.4Ghz trigger will have dramatically longer range but is also more susceptible to interference as there are so many things that operate or near 2.4GHz (wireless phones, WiFi routers, etc...)
 

by john on Fri Feb 24, 2017 12:56 pm
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E.J. Peiker wrote:
john wrote:Joe...thanks for you're input.  That looks like it would work well. I have ordered some off camera flash hot shoes but couldn't find any with 2 -3.5 mm females so ended up getting ones with one PC and one 3.5  mm female, so if one of the hot shoes decides to quit I can still tether the flash via the PC connection.  I've decided to not tether to the camera at this point as it seemed to work fine triggering the first flash remotely and tethering the 4 flashes from the spliter hub.  Whether that solves the flash inconsistency remains to be seen but I won't know until I can get back to some place with hummingbirds hopefully this summer. If not I can always tether back to the camera hot shoe as you have done.  Thanks again for your input.  It was disappointing getting lots of really nice poses with ghosting so I'm hoping this solves that problem,  

On another note,,,
The triggers I have are 433 mHz and I noticed the more costly ones are 2.4 gHz.  I wonder if that frequency gives a more consistent trigger or if it just increased range?
433MHz not 433 mHz (Megahertz not Millihertz ;) ) - the difference is range.  A 2.4Ghz trigger will have dramatically longer range but is also more susceptible to interference as there are so many things that operate or near 2.4GHz (wireless phones, WiFi routers, etc...)

That darn metric system :)
 

by Greg Downing on Sun Feb 26, 2017 11:03 am
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john wrote:
Greg Downing wrote:John,

It's hard to say if it's ambient light or not but one thing to check is to take a shot without flash with the bird in the target zone and see if you get anything registering. If you do then you will get ghosting. You cannot have sun shining on the bird.

Thanks Greg....I tried this today and for the most part it works to get good images, but whenever one of the hummingbirds does a major power turn I'm still getting a bit of ghosting.  I can live with the keeper rate I'm getting for this trip but will sort this out before I go again.  I was down to  100 Iso F16 and  1/64 at one point.  I guess even though I'm in the shade the ambient light from the bright sunlight changes enough to infiltrate my setup on occasion and the flash setup isn't enough to overcome that.  Thanks for all the help everyone...I'm not going home empty handed. :)  I'll post another example once  I get some downloading and processing done.
What was your shutter speed? Always at max sync speed or 1/3 below depending on your set up as some wireless transmitter/receiver set ups do not sync at max speed every time so going down 1/3 helps with intermittent black banding at the bottom of the frame. I know that's not your issue but worth noting. If your shutter speed was around 1/200 and you were in total shade with ISO 100 at F16 there is no way you're getting an ambient light issue. Sun creeping in is another issue and should be avoided. 
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by E.J. Peiker on Sun Feb 26, 2017 12:50 pm
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I have to second what Greg is saying. Specifically when I was at 1/250 about every 6th frame would get partial blanking. At 1/200 that never occurred. And ISO 100 at f/16 is going to be a black frame in the conditions described so any blurring is going to be from either an out of sync flash or one flash putting out a different power level than the others.
 

by john on Sun Feb 26, 2017 1:05 pm
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Thank Guys. I did try everything you are mentioning and also had every 5th frame or so with a black strip. No amount of shutter speed adjustment seemed to eliminate that. I was basically stumped on a solution so just shot lots to get some keepers. I can only assume that one of my receivers wasn't performing consistently or one of the flashes is kaput. I have all the stuff to wire things together coming now so will give that a try this summer if I can get down into southern BC. That way I will be relying on only one receiver so that should tell me pretty quickly what the problem is. Fingers crossed.
 

by E.J. Peiker on Sun Feb 26, 2017 1:14 pm
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If no shutter speed eliminated the black strip then that proved beyond a shadow of a doubt that at least one of your flashes was firing at a different time. More likely one of the receivers than flashes but that is easy to figure out by taking single flashes with single receivers and figuring out which is the culprit.
 

by Greg Downing on Sun Feb 26, 2017 1:41 pm
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E.J. Peiker wrote:If no shutter speed eliminated the black strip then that proved beyond a shadow of a doubt that at least one of your flashes was firing at a different time.  More likely one of the receivers than flashes but that is easy to figure out by taking single flashes with single receivers and figuring out which is the culprit.
 I agree it sounds like a bad transmitter/receiver set up. There should be no reason to use wires… What a pain but I guess if it's just one set up....  I would've just gotten a new set of receivers/transmitter.  I've been using photix ones from our store for a decade without a single issue but I always have back ups on hand. 
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by john on Sun Feb 26, 2017 2:10 pm
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That probably would have been a good idea from the start, but now that I"m invested in the cheap setup I'll keep trying to solve this with them until I can see no solution....then I'll do what I should have done in the first place and get decent ones. :) The old adage...you get what you pay for.
 

by Greg Downing on Mon Feb 27, 2017 5:40 pm
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Keep us posted :)
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by john on Wed Jul 05, 2017 11:11 am
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So finally got a chance to try out the "wired" system and am happy to report the the ghosting is completely eliminated. The culprit was the receivers not syncing. I now use one receiver and wire 5 flashes from that receiver with 3.5mm stereo chords to flash hot mounts similar to SantafeJoe's old system. Also still using 2 different types of flashes with no problems. The receiver is still triggered by radio signal from the transmitter on the camera hot shoe. Alan Murphy....thanks for the recommendation!
 

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