Dark pics troubles with TG6 + Inon S2000 + Archon W40V

Hello,

It's been some time since I found myself with VERY underexposed pictures despite using my Inon S2000 strobe. I do macro, I use Aperture mode. In addition, I also have an Archon W40V lamp (2600 lumens). I don't quite understand what is going on . I sometimes get very dark shots even the strobe triggers
If anyone has any idea where my problem is ...

Thank you in advance.

I think we might need more details - settings you are using on both camera and strobe that is what aperture, ISO , is flash TTL or manual?  Full strobe settings - TTL or manual, magnet in or out etc.

Indeed. If you are using one of the popular setup guides (i.e. A mode, F8, Ev -2) then that is specifically designed to give you 'dramatic' (i.e. very dark background) shots. Knowing how you are setting up the camera is important.

I used the almost identical setup except a Bigblue video/spot light instead of Archon you mention. I got the dramatic 'very black background' shots using the settings above (also with the S2000), but that was exactly the effect I was seeking on my macro shots.

An example photo would also help get an idea of what might be happening.

I have this same issue with my TG6 and it seems like it's a shutter failure or something that is preventing light from getting to the sensor since there is available light to use if shutter was working properly. It happens intermittently so I can't connect any pattern. I'm also using aperture priority with macro focus, ISO set to 100. On today's dive it did it a lot, way more than ever so I'm concerned it's just going to keep getting worse.

If there is something on the EXIF data I can look at that will indicate if something is going on file wise please let me know. Otherwise I think it's a hardware issue.

Are you using manual flash on the TG6? On the flash?   What aperture are you using?  What flash are you using? 

with optical triggering the camera doesn't know what the flash is set to and the flash doesn't know what the camera is set to, so you need to have settings between the two lined up properly, so we need to know all the settings I've mentioned.

The flash settings shouldn't prevent any exposure from happening at all though, correct? And if it was a flash setting, why would it happen intermittently and not every shot? I have one video light (constant light on) and a strobe so even if the strobe didn't fire or didn't fire properly, the camera should still expose the shot based on available light, correct?

But here are the answers to your questions:

Manual 1/64 on camera, manual mode on YSD2 strobe

EV -1.0; F18 at full zoom; ISO 100

I am not changing anything between the shots that work and those that don't. I believe the strobe is still firing, just the file isn't recording properly.

You need to have the right settings so the flash will fire at the right time.   f18 is well stopped down, so the video light would hardly register at all so I wouldn't expect it to provide much exposure - it is at least 7 stops less bright than your flash at full power.  f18 on the TG-6 is achieved with a 3 stop ND filter from f6.3 so really is just throwing away light.  At f 6.3 you might have some chance of the video light providing some exposure.  The main reason to use f18 would be to get a black background in bright conditions.  I would suggest using f6.3 and see how that goes.

Just to confirm that you are using the single bolt - green manual setting - the flash I think would not work without that being set.  Also when you say the frame is dark - you mean it's completely black?

It could be a cable issue - the YS-D2 has issues with the slave sensor it is not very sensitive  and needs enough light to trigger - normally an on board flash is good enough to trigger it, but is there's a cable fault it may not trigger properly all the time.  You could try raising flash power a little - try 1/32 and see if the triggering improves.  Have a close look at your cable to check for any damage hold one end at a light source and see that you can see it through the other end of the cable - move the cable around to see it remains visible. 

Does the shutter speed vary between shots that work and those that don't?  If you are at depth it should probably be at the min shutter speed programmed in for full zoom which I think is 1/100. 

Is the dark frame random or immediately following a correctly exposed frame?

You can test this by shooting into a mirror with you rig if the flash goes off at the right time you should certainly see it in the mirror in the image.  Use lower manual powers on your flash when on land to avoid it over heating.  Take a few shots moving the cable around and see if that makes a difference

Thank you so much for your reply. This still doesn't explain why it works intermittently (so yes, it is random, coming before/after shots that have exposed properly). If it was a settings issue wouldn't it not expose properly every time? When it doesn't produce a dark frame, the exposure is fine. This is my setting for macro only where we want dark backgrounds.

I only have one strobe so it's not a slave issue, but I suppose it could be a cable issue, I looked at it but it appears fine. I will try moving it around and see if I can see that affecting the performance. 

Oh and sorry, the file settings are exactly the same between the files that work and those that don't (shutter speed included). I tried comparing the EXIF data and didn't see anything that jumped out as an obvious difference.

We need to go through all the settings to make sure that is not the issue - you can for example have the flash not fire immediately after a high power dump.  If it's an issue with the camera it should also do it with ambient light shots with the built in flash working - so that is something to try.  If it works all the time taking ambient light shots with the flash enabled then it is something to do with triggering the external flash. 

So you could take a series of shots in outside daylight with just the camera so there is enough light to get good ambient exposure - try it at f18 and at f6.3.  If you get occasional dark frames with that  then you have a camera problem.  If it is reliable there then you have an issue with triggering the external strobe.

I would still recommend trying to use f6.3 unless your background light is very bright and you want a dark background.  I assume you confirmed you were on single bolt - green manual on the strobe.

Testing it yesterday I am leaning towards it being a strobe firing issue, if a misfire does indeed cause the processing to not perform properly. I only had one black screen underwater with almost all settings the same as what I was using before except for changing the manual power to 1/32 and cleaning/reinstalling the cable ends to the housing and strobe. Will keep trying a few adjustments to make sure that is what is really happening. I also have a new cable I'm picking up soon so I may try it with that and see if that improves reliability. Thank you!

Sounds promising - definitely try it with the new cable.