Anyone use the Epoque es-150?

As a novice to the world of strobes, I had some basic questions about my set-up. I have been shooting with an Olympus d-40 in the Pt-012 housing. It takes great close-ups with the internal flash but at any distance photos became blue or grey - obviously I needed an external flash.

I added an Epoque es 150 manual strobe with a fiber-optic connector (slave). After a couple of days and James' help (thanks) I now have the two firing a the same time. Thats a good thing.

However, after some experimenting I find that some photos are way too bright (overexposed?) and some are too dark. The back of the strobe has manual setting s from "GN3" up to 15 in 3,6,9,12,15 increments. 3 is the weakest, 15 is the strongest.

My question is this a matter of practice or are there some rules of thumb as far as camera settings to accomodate the extra flash. I beleive the olympus defaults to 1/60 and F8.

Is there anything I need to change to make life easier other than take a class? Im leaving for Bonaire in March so Im crash coursing this strobe thing.

Any help or comments are appreciated.

Regards,

Jeff

Hi -

The guide Number (GN) is equal to the path length from camera to object (d) times the F/# of the camera, ie GN = d x f/#. So in your default mode with f/8 and a GN of 15 (probably meters, should say in manual), you need to be 15/8 = ~ 2 meters (6 feet) from the object for proper exposure.

To shoot closer than 2 meters - just multiply the f/# x distance - and choose the closest guide number. For 1/2 meter (20 inches) distance at f/8, multiply 1/2 (distance in meters) * 8 (f/#) = 4 (guide number); so set your strobe to 3 (closest GN); and review your exposure - if too dark, increase strobe to next power setting.

Guide numbers are for ISO 100 film equivalent (should be the default for your camera). Hope this helps

Didn't they give you a little chart or sticker with the strobe setting, F/# and distance relationship? Refer to that to start with. With practice you will be able to judge distance, exposure and strobe settings and you won't need to refer to it anymore. Just remember that objects appear closer UW....

thanks for the advice..sounds like i need to make my own sticker or buy a more expensive flash next time

Hi,

I'm also using a ES-150. I don't have a fiber-optic connector. The strobe is just synchronised on the main camera flash (slave) using the off/on selector.

I can confirm that there were nothing included in the package explaining how to deal with the GN. I really think that it's more a question of experience and 'feeling' underwater. The more you shoot the more you'll able to judge the distance and adjust the guide number ... Anyway I'd like to get a fiber-optic connector.

Treefrogjeff,

Did you buy the connector or did you manage to build one ? That connector wasn't available when I bought the strobe. I really wonder if there is online shop selling in Europe ...any clue ??

Thanks

Hi. Took the ES-150 and Canon S40 to Truk. The housing survived a 56m dive (rated to 30) and I learned a little more about lighting. I got the fibre cable with the Epoque in the packaging but that was here in Japan.

Well the results are pretty darned shoddy but I think I began to improve (the closer I got to the surface light that is ;-) ).

http://psg.mmdc.net/gallery/trukdive

Overexposure was the main culprit (when the flash fired) but I started to get the hang of the GN setting towards the end. Under those conditions and without a wide-angle I guess it never needed to go over GN5 anyway.

The biggest pain (and many report this with the S40) was the lens fogging up after 40 minutes in 30-degree water. I found that keeping the whole thing wet and shaded prior to the dive seemed to help but it sure was annoying.

The movie mode was actually quite useful and I wish the resolution could be slightly better. Ok we know I should use a digicam for that but just a slight improvement and maybe an auto-f/white balance would've been good.

-PSG-

Hi,

Im using a Canon S45 and I've just got an Epoque with Fibre Optic, cant wait to get it underwater...

I bought my setup from the UK, will ship to anywhere in Europe.

Camerasunderwater

Like you Im also after hints and tips.

Regarding the fogging up issue, I've had it too but I've managed to almost get rid of it by putting little silica gel packs into the housing, they absorb quite a lot of the moisture. Only problem is having enough of them and drying them out.

Give it a go!

Skinny

The guide Number (GN) is equal to the path length from camera to object

Not exactly. True, the guide number is equal to the aperture times distance. One of the many ways to express the equation is Gn=A*D. But it is referring to the distance between strobe and subject, not camera (lens) and subject.

So in your default mode with f/8 and a GN of 15 (probably meters, should say in manual), you need to be 15/8 = ~ 2 meters (6 feet) from the object for proper exposure.

The strobe in question is powered by 2 AA batteries. The guide number rating of 15, is calculated in feet, not meters, at ISO 100. These specs have been verified by the distributor.

Therefore the proper calculation using the formula stated, GN=A*D, would be:

gn 15 = f/8*? Answer about 2 feet.

Place the Epoque ES 150 DS strobe, manually set to gn 15, about 2 feet from the subject at ISO 100 when aperture is set to f/8.

hth,

bob

If like me all those math calculations leave you cold then why not simple experiment. That's what digital cameras are great for. If it's macro (close) within a foot or so set the GN to 3. If its further away set it higher. Then take pictures adjusting the guide number accordingly. Want more light dial it up, want less dial it down. After a while you will begin to get a rough idea of how much flash you need. I can tell you that the ES150 strobe works very well and will take great photographs within the limits of the strobe. It's a flimsy design of strobe but it works well enough for all that..... what do you expect for that amount of money!

Problems can arrise if you are using the camera in P mode (fully automatic). In certain extremes of lighting conditions, with the camera setting the aperture, it is possible to push the strobe beyond it's limits. When it's dark or gloomy the camera will choose a smaller aperture (full open). If you are trying for a macro shot, chances are that even with the lowest GN of 3 you will overexpose the pic. Likewise in bright situations the camera will choose a larger aperture. This aperture may mean that the strobes effective distance even at a full power of GN15 will not be enough and you end up with a blue/green photograph. Best way is to use the camera in manual mode (M) or at least aperture priority mode (A) which at least allows you to dictate apertures that will suit the strobe. To find out what they are...do the math or experiment!