question to photographers?

When you do water drops, it's the flash that freezes motion NOT the shutter speed.

The only criteria for the shutter speed is that it's at or below the max sync speed for your camera - the fact that you are seeing the second shutter curtain as a black line indicates that you are right on the borderline of flash sync speed.

To get crisp, clear drops there are two things you need to check;

- focus. Make sure that you are in manual focus mode and focused accurately on where the drops will fall - also ensure that your aperture is giving you an adequate depth of field (ie don't shoot wide open)

- flash duration. The faster the flash duration, the better the freezing of the water drops will be. Speedlight flashes have a faster duration the lower the power they are set at. For example, the YN560-III I use has a flash duration of about 1/350 sec at full power (1/1). At 1/128 power, the flash duration is 1/10,000 sec - this is what you need. So dial down the flash power (& have the flash closer if you need more exposure).

Your shutter speed you can have at around 1/125 - the slower it is, the more ambient light you will capture in the scene.

An example of mine;

https://www.flickr.com/photos/deepbluephotography/...

Deep blue's analysis of power levels is very helpful - totally correct, as is joe's comment that ambient light is what is causing your blur issue.

Set up the shot then turn off the lights and work in total darkness. Use a flashlight to get around the room. Shut it off then open the shutter and hit the flash.

If you're getting blurring with the flash, there's too much ambient light. Use the flash as your only light source.

Use the high speed synch so you can use higher shutter speeds, see the link