Strobe solutions

[desiredbard]

Hi again

Looking for a strobe solution on my SONY P100

To avoid these left bottom corners: http://www.scubaboard.com/gallery/showgallery.php?cat=1844


Currently looking into the HVL_ML20M Torch (which of course like aal sony products is excluding battery and excluding bracket which means you nearly have to double the price)

Anyone has any other suggestions, (external strobe that gets triggered on the internal flash <whats this properly called> what are the drawbacks>

Regards
Bas

 

[havnmonkey]

you're looking for a slave flash with some sort of fiberoptic sync cord. The sensor attaches (you might have to MacGyver that one) to your housing in front of the internal flash, when it goes off the external strobe is triggered. Nearly all strobes made can be fired this way which makes them compatible with virtually all cameras. If your camera has a pre-flash then you should make sure the strobe has preflash settings as well.

$$Price$$ is a minimum of $200 for a Sealife or Sunpack G and then $500 minimum when you get into Ikelite or Inon.

The Sealife and Sunpack will come with everything you need to start out (except maybe a diffuser) and have different power settings and pre-flash settings.

 

[fairybasslet]

Isn't this just an aiming problem? I seem to have the same kind of problem and I hope it's not the strobe. I just spent $500 on a it and it seems like only the upper half of my photos are lit up.

 

[havnmonkey]

if you have an external strobe, yes aiming is a skill that must be learned; I'm not that great at aiming mine yet and getting those shadows where I want them. A diffuser helps also.

If it is an internal flash the only aiming you can do is to get in closer or back up... usually you will get a shadow with the internal.

I think it is just inevitable before any u/w photog gets a strobe-- or two. It gives you more control.

 

[donnyb]

Bas: looks like the internal flash is being shadowed out by part of your housing???
If so you will need the external slave flash as described above.

Fairy basslet: looked at your post gallery & did not see your problem. Although you could be having an aiming problem with your strobe, if you are using a film camera you could be exceeding your sync speed on the shutter, which will result in partially dark images. Not sure if that happens with digital cameras. Film cameras have a mechanical shutter, and it has to open fully before the strobe fires and close after. If the shutter is too fast, it ends up blocking part of the film as the strobe fires. Try changing shutter speed to a slower setting. If problem goes away its not aiming of the strobe. Owners manual will have the sync speed of your camera, the max shutter speed you can use flash.

 

[fairybasslet]

Bas: looks like the internal flash is being shadowed out by part of your housing???
If so you will need the external slave flash as described above.

Fairy basslet: looked at your post gallery & did not see your problem. Although you could be having an aiming problem with your strobe, if you are using a film camera you could be exceeding your sync speed on the shutter, which will result in partially dark images. Not sure if that happens with digital cameras. Film cameras have a mechanical shutter, and it has to open fully before the strobe fires and close after. If the shutter is too fast, it ends up blocking part of the film as the strobe fires. Try changing shutter speed to a slower setting. If problem goes away its not aiming of the strobe. Owners manual will have the sync speed of your camera, the max shutter speed you can use flash.

Donny, thanks for looking at my photos. The one of the out-of-focus seahorse is a perfect example of what I am talking about with my aiming problem. I do have a difuser and I use a digital camera. It was my first time using the external strobe. I was very disappointed in my results. I suck.

 

[donnyb]

Donny, thanks for looking at my photos. The one of the out-of-focus seahorse is a perfect example of what I am talking about with my aiming problem. I do have a difuser and I use a digital camera. It was my first time using the external strobe. I was very disappointed in my results. I suck.

Ok I see it. It does look like you are shadowing out part of the scene somehow.
You will need to experiment with the position of the strobe. Take your setup somewhere (pool if necessary) perferrably in low light. Get settled on the bottom with something to photograph, could be a plastic toy or whatever. Then shoot & review with your LCD panel on the camera back. Move the strobe toward or away (in or out)from the camera to see if it has any effect on the problem. The strobe should not be close to the lens (makes backscatter) and try to keep it sort of facing straight ahead, or only slightly angled in. Practice practice practice. At least youre not using up film!

 

[havnmonkey]

Yes you will need to practice... if you have any way on getting a cheap easy dive, shore, lake, or spring you could dedicate it to just fiddling.

Also, I am looking into attaching my small dive light to my strobe arm with a diffuser on it so I can have a focus light. Remember that your camera is built to analyze and compensate for available light above water; and since the strobe isn't getting a "measurement" from the camera it must be adjusted by you. Also depressing the shutter button will focus the camera; it focuses using the available light-- low light equals bad focus.

Also If you look at the exif info you might notice that your aperature was f/2.8 as far as I know the lower the f/ the shallower depth of field... the seahorse might have been just outside the depth of field... so get closer or lower the shutter speed and raise the aperature. Maybe, just a thought.

 

[desiredbard]

FairyBasslet, have you got your strobe on the right habd side of the camera?
Shade appears to come in from the right top. I would think (with no strobe experience at all that your stobe is either not placed high enough or to far backwards?

Great pictures though.... Hope to get simmilar ones in Kota Kinabalu and Langkawi, although I've been warned about the monsoon season and I am a bit worried about how great the conditions are going to be.

 

[fairybasslet]

Thanks for the feedback. Modeling light is on my wishlist. The seahorse was a low light situation (plus I was kind of rushed because I was the last one in the group to shoot it and the group was disappearing fast LOL) I was going to strap an extra flashlight to the arm of the strobe, but never did for some reason. My strobe is on the left. Yeah, I do have to practice practice practice. Most definitely.