1/160 shutter speed

[Hoag]

@Hoag thanks, I use two ys-03 strobes the exposure is perfect and most images are below 25-30ft the strobes do a great job of bringing colour back to I. Ages but I can't seem to get the blur to stop last dive I went on for example... Iso was 100 f-stop was 4.2 and 2 s&s ys-03 strobes and shutter speed set at 1/160th. Saw a couple of octopus water current was slight movement, took photo up close & focused perfectly just as they started to move and a blurred Image?? Any ideas?

In that case, I'm sorry, but I don't know for sure what the problem would have been. If the strobes fired, the burst of light from them should have been such a short duration that it should have "frozen" the movement of the octopus.

 

[Hoag]

Good photo, do you go by histogram?

Not normally. In the camera I use the LCD as a guide for how close I got the exposure. It is not fool proof, but I can usually get it pretty close and then fix it when I edit the pics on my computer. On the computer (in Lightroom 4.4), I will set the White and Black levels to just below where they start to clip and then adjust the Highlights and Shadows to give the best possible (to my eyes) image.

 

[jd950]

The thing is, if you are shooting in areas with a decent amount of ambient light, it can be hard to set the aperture small enough and the shutter fast enough that the only light is from the strobes. In that case, you may get some motion blur if you are limited to 1/160 and are shooting a relatively fast-moving subject. There is a point at which closing down the shutter causes its own lack of sharpness in the picture (diffraction limiting) and it is better not to exceed that limit, which changes depending on camera and lens.

When I used a camera limited to 1/160 flash sync, I found it did cause problems sometimes. I have seen people say/write that with two strobes on high power, the strobe light so overwhelms the ambient light that maximum sync speed is not an issue. I am not so sure about that at shallow depths in clear water on bright days. I think that generally, if the ambient light is something like 4-5 stops less than the strobe exposure, you are likely to be able to freeze motion with a powerful flash. Less than that and you are more likely to the effect of the ambient light and at 1/160 that may include motion blur.

You may want to experiment with your camera. It is possible you will not have sync problems if you bump up the shutter speed a little bit beyond the manufacturer's specification.

Hope this helps some.

 

[BFRedrocks]

The A6000 flash sync speed is 1/160th second. That is the fastest shutter speed that you can set the camera if you are using the flash. This can be an issue if you are using only the built in flash, but is much less of an issue if you are using a strobe or even better yet, a pair of strobes.

I shoot a Sony a6500 with dual YS-D2s, so I'm curious, how do you find out what the "flash sync speed" is?

 

[Hoag]

I shoot a Sony a6500 with dual YS-D2s, so I'm curious, how do you find out what the "flash sync speed" is?

Sometimes, it can be kind of tricky to find, but it is on the Sony website for their cameras.

In your case, go to the Sony website for the A6500 and then click on the "Full Specifications and Features" tab and scroll down to the "Shutter" section and the Flash Sync speed is listed (it is also 1/160 second for the A6500).

For many cameras, B&H will list the Flash Sync Speed on the "Specs" tab although if you find a camera where this differs from the manufacturer's spec, I would go with the manufacturer's specs.

 

[ggibson]

The RX100 series is better in this regard and will sync up to 1/2,000s.

But the sync speed is really just to control ambient lighting. Strobes should be freezing the action regardless of shutter speed because their light only lasts for a short duration (like 1/10,000).

So OP--if you're getting the right flash exposure and the image is blurred, it is likely not motion blur. Are you sure it's not missed focus? Maybe you could post your pic for us to help.