Flashes Part 4: Slow Sync Flash Modes - Photography with Imre - Episode 16

[Ronaldograxa]

hi there.. How come there is no motion blur of your body (subject ) when your move while the shutter is open? I dont get it... thanks for the tutorial

[binarygraphite]

@Ronaldograxa Hi, thanks for the comment! There is no motion blur because when I was moving, I was in total darkness; in other words all the lights in the room where shut off. The only light came from the flash (either at the start or end of the long exposure). So of course if there is no light, then there is no motion blur, or anything else for that matter, to be recorded by the sensor.

[bninjabninja]

Thanks.. But when the sensor stay exposed for 1 or maybe 2 seconds how doesn't that cause the subject to be overexposed ?

[binarygraphite]

@bninjabninja It could! It just depends how much ambient light is on the subject. Indeed, if there is plenty of light from other sources, then the possibility exists to over-expose the subject, so that's where the photographer must compensate for that (that is to say they might need to take a few shots to get the picture just right by varying the exposure time).

[bninjabninja]

@binarygraphite Yeah i know, but what confuses me is that when you take a picture of an object with flash is set to slow, and 1/10 shutter speed, it turns out just like if you use 1/200 shutter speed. The only thing changing is the background.

So how is the subject having almost the same exposure ? Thank you..

[binarygraphite]

@bninjabninja Ah ok. Since the shutter speed is slow, the sensor is exposed to the darker background for a longer period of time which allows the background more time to expose (thus becoming brighter). All the flash does is help illuminate the subject that is up close.

If the shutter speed is fast, then of course the sensor is not exposed to the dim background light for a long enough time period, thus you end up with a darker background.

[binarygraphite]

@bninjabninja And just to be clear, the flash fires normally. The "slow" part has to do with the shutter speed being slower. So depending on whether you are set to first or second curtain, the flash will fire either at the start or end of the exposure, respectively; just as shown in the video.

[itaintrite]

Thanks for this video Imre, but I still have a question. If I'm taking a portrait in low-light, will the 1st curtain mode or 2nd give me the sharpest shot with a long shutter speed for ambient light?

[binarygraphite]

@itaintrite You're welcome! Generally 2nd curtain, but it could go either way depending on what the lighting is like, especially in regard to how well the subject is lit by other sources. But for 2nd curtain, the idea is that the background and subject are dark, shutter opens to capture ambient light, then the flash at the end illuminates the subject well to capture details and "wash over" the ambient light source spillage on the subject that might have occurred before the flash.

[itaintrite]

@binarygraphite ah, thanks for the info. That last part certainly answered my question.

[einsteinsaifoo]

Subscribed coz u r great. :D

[binarygraphite]

@einsteinsaifoo You're very kind, thank you!

[einsteinsaifoo]

Great.... :D

[glennavarra]

Thank you!

[binarygraphite]

@glennavarra You're welcome!

[10STRINGS]

Thank you Imre. your videos and illustrations are excellent and well done. All my questions on slow sync flash was answered in your video. Thanks again. and I really appreciate it! :)

[siliconsurf]

Do you usually shot in A mode at night with the 2nd curtain setting?

[binarygraphite]

@siliconsurf I generally prefer 2nd curtain, but it's a toss up between aperture priority and full manual. If I get the desired look with A mode, then of course I use that. However, I often find that the shutter speed could be slower to achieve a better exposure, and as such I'll switch to manual to I can adjust as much as I'd like.

[canarycare]

Thank you :)

[binarygraphite]

@canarycare You're welcome!

[trl510]

another awesome tutorial

thank you

[binarygraphite]

@trl510 I'm glad you enjoyed it! Many more to come!