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DS-125 slave issues


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#1 bmazin

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Posted 23 April 2002 - 07:51 PM

I've got a 4040, PT-010 and added an ikelite DS-125 with slave sensor in mid-March. I've been playing around with it and noticed some things:

1) TTL seems to work ok at wide angles with moderate apertures. However, it does not EXACTLY mimic the built in strobe. On shots that the built in stobe does not have enough power to fill in adding the DS-125 does not seem to help much.

2) Macro shots at small apertures (F10) are always way overexposed with the DS-125. At F8 they are a little over exposed, at bigger apertures it looks ok. Using the internal strobe small apertures come out fine. Strange!

Is this normal behavior? Did I get one of the bad batch of slave sensors? Any input appreciated.

Ben

#2 bobjarman

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Posted 24 April 2002 - 05:41 AM

Doesn't sound like the same issue. The issue previously discussed had to do with the strobe quenching way to early and causing underexposure.

The ds125 is a very powerful strobe. I believe don had said earlier that he was dialing in flash compensation on most of his shots, even with TTL. You might try that if you can. Also, you are totally blocking your internal flash, correct?

I'll be interested to hear what others have to say about this one, its the first time I have heard about too much flash on macro shots with ttl.


added:

One other thought, even with the internal flash blocked, when shooting macro, wouldn't it be logical that with a clear housing some of the blocked light from the internal flash would still light a subject a few inched away from the housing, assuming you are using a clear housing? If so, it would seem to me that Flash compensation would almost be mandatory. Any thoughts?






[Edited on 4-24-2002 by bobjarman]

#3 SharpDiver

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Posted 24 April 2002 - 06:32 AM

The first question is, was the internal strobe blocked? If not, then I would be suspect and would call Ikelite. That is exactly what happened to me on the first dive. I didn't notice extreme under-exposure until I blocked the internal.

#4 bmazin

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Posted 24 April 2002 - 09:29 AM

Originally posted by SharpDiver
The first question is, was the internal strobe blocked?  If not, then I would be suspect and would call Ikelite.  That is exactly what happened to me on the first dive.  I didn't notice extreme under-exposure until I blocked the internal.


Internal stobe was blocked with aluminum foil.

It is a strange situation - too much light on macro shots (with an odd reverse aperture dependance), too little on wide angle shots that the strobe should be able to fill. I think I'll ship the sensor back to ike for a look.

Ben

#5 rstark

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Posted 24 April 2002 - 10:18 AM

Try my little trick posted in this thread to see if you get more consistant results.
http://www.wetpixel....ead.php?tid=129

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#6 ikelite

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Posted 24 April 2002 - 10:43 AM

bmazin definitely should send the sensor directly to Ikelite, and should include the strobe just to be sure everything is correct. Product is supposed to work as intended.

ike

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RA numbers are never needed to get something repaired. Item can be sent directly to us without going through a dealer. We appreciate the opportunity to correct problems whey they occur.

[Edited on 4-24-2002 by ike]

#7 scubapearce

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Posted 25 April 2002 - 12:16 PM

Before you send your strobe to the folks at Ikelite try one little test. Photograph yourself with the strobe on TTL in the mirror and see if the flash and DS125 show up in the picture.

After testing my DS125 unit underwater and with a wide angle lens I found exposures were varied and overly effected by the internal strobe and the spotting light. By taking a picture in the mirror I found the Strobe and Internal flash were out of sync with the camera. I have since contacted Ikelite and they have the strobe for testing. They did say this was an issue with the C4040Z in particular.
Hope this helps,