Anyone using this flash? SAMSUNG NX SEF-20A FLASH

Faith Yeung wrote:

NewForce wrote:

Very nice flash shot Faith.

Was it a SOOC shot or after PP?

If it was a SOOC shot then I must say, SEF20A and Samsung A-TTL flash metering does work a miracle without creating any flash hot spot on the faces.

I shoot RAW and adjust white balance.

For exposure, I am not sure whether I have pressed +0.7 EV on SEF-20A. For bounce flash, I experienced a little bit underexposure in general.

Thank you for your reply.

Judging from the kids, person at the back and window frame heights, I've think the house ceiling around 2.4~2.5m.

Not sure which lens you are using but with F2.8, and the given DOF between the kids and rear window (2.5~3.0m apart), probably a 20mm lens. So my guess,

1. The walls white (beige?) in color, bounce flash probably return around 50% flash GN. With SEF20A you're get about GN10.
2. Shooting distance around 1.6~1.8m. 75~90 degrees bounce flash you're at 2x distance,  increases to 3.2~3.6m.
3. GN10 / 3.2m = F3.1,
4. GN10 / 3.6m = F2.8

See both of my estimated GN vs distance come close to your aperture use. If you happened to be shooting at longer distance, like 2.3m then,

GN20x50% = GN10/4.6m = F2.2 thus using F2.8, +0.7EV FEV was needed.

Think that's about the max SEF20A can do using F2.8 @ ISO100. If you need to cover more distance, probably you need to up ISO to 400 (2x GN power).

Using flash with higher ISO like 800 or 1600 with NX10, you probably better off with higher GN flash, or change to a newer NX camera like NX300 or upcoming NX30. This logic apply even if you change to another brand APS-C camera. Just my 2 cents of tips, I could be wrong as I've never use a NX10 and SEF20A before.

Oh i see ISO200.

I did thinking of the 30mm lens, but then if you are on ISO100, so 20mm lens. So with the 30mm lens your shooting position should have been pushing back by some distance. So if you don't mind, below just for fun calculation and to prevent my brain go more rusty,

1. SEF20A bounce flash return 50% = GN10. ISO200 mean GN10 x 1.41 = GN14
2. Shooting distance now 2.3/2.5/3.1m, at 2x distance, 4.6/5.0/6.2m.
3. GN14 / 4.6/5.0/6.2m = F3.0/F2.8,/F2.25

So again estimated GN vs distance come close to your aperture use. If you happened to be shooting at longer distance, like 3.0m then, GN20x50%xISO200 = GN14/6.2m = F2.25. With F2.8, +0.7EV FEV was needed. More flash calculation practices mean better results.

I too got an eye on Sony DSLR before. But due my horror experience with NEX-5N, I have dropped the idea. Should be fun using a Sony DSLR, if don't mind about the weight.