Unpredictable exposures with rear curtain sync and bulb shutter on D7000

[epp_b]

I am having very unreliable results with using my SB-600 with my D7000 when setup in bulb mode, rear curtain sync and manual flash power. It doesn't matter how I connect the flash (hotshoe, cable, CLS, RF triggers). The flash will fire every time without fail, but most of the time, it doesn't actually affect the exposure ... as if it's firing too late or something. This problem does not occur with my D40. I don't recall having this problem with the D90 I used to have either.

Could someone with a D7000 and a speedlight reproduce this experiment to confirm whether this behaviour is normal?

1. Attach a speedlight using any connection type (directly on hotshoe, remote with cable, remote with CLS or remote with RF triggers)
2. Put the flash on a manual power selection, use any power level you like
3. Use rear curtain sync
4. Put the shutter in bulb mode
5. If you're using the flash remotely, point it directly at the lens. If it's on the hotshoe, point the camera at a mirror.
6. Take at least 5 exposures and answer these questions:

A) Does the flash fire every time?
B) Does the flash affect the exposure every time?

Thanks, your answers are appreciated. If you have different Nikon camera that you could test with, I'd be interested in seeing those results as well.

 

[Overread]

Few questions:

1) Is the manually selected flash power actually enough to affect the final exposure

2) Is the distance between the flash and subject remaining constant whilst shooting - esp if you're at close distances then even small shifts in the flash position will affect the light coverage.

 

[epp_b]

1) Is the manually selected flash power actually enough to affect the final exposure

I've tried this at various settings between 1/64th and 1/1 with the same end results.

Is the distance between the flash and subject remaining constant whilst shooting - esp if you're at close distances then even small shifts in the flash position will affect the light coverage.

I should have clarified: for this test, I am pointing the flash head directly at the lens (or taking the test shots in front of a mirror if attached to the hotshoe), so there's no way to miss it.

 

[astroNikon]

Im trying but i have to look up rear curtain flash setup first

 

[astroNikon]

Yes
Yes

You probably know this but to set push flash button on left of top prism area, rotate dial until REAR on LCD
i shot several shots including putting my foot in front of the flash to confirm it.

With rear flash and bulb the flash did not fire until i lifting my finger off od the release
With rear the photo has w white "fog" to it each time or if flash pointed directly at it just white out. I did various exposure lenghts.

Bulb mode
Su800 controlling. OCF. SB-800

 

[epp_b]

Interesting. Remind me, the SU-800 is shoe-mounted CLS transmitter, right?

 

[astroNikon]

Yes
I'd be lost without my su800 but I use it in Manual for everything.
SU-800 Wireless Speedlight Commander from Nikon

 

[astroNikon]

Now I just tried it without my SU800

SB-800 on Master ON the camera hot shoe shooting into a mirror.

setup as Manual 1/128
Bulb
REAR

Upon initiation of release the flash flashes
and upon release of release the flash flashes

=======
with the popup flash
bulb
rear

upon initiation of release the popup flash flashes
that's it .. popup does not flash at the end of the release

I haven't not used my SU800 for flash since I got it ... so I've rusty with all of this

my eyes are also kinda blind from all the flashes too.

 

[astroNikon]

so, it looks like everything works fine as expected when I use my SU-800

the other scenarios provide varying results.

disclaimer though, as mentioned, I haven't not used my SU-800 since I got it which is when I first started doing OCF which was in July when I bought a SU800 & SB700. I have SB800s and a 700.

 

[epp_b]

OK, can you try a simpler test? Just put the flash on the hotshoe and take several shots of varying lengths in front of a mirror with rear sync. Can you see the flash in the exposure every time?

 

[astroNikon]

(I had to redo this test)
SB-800 Flash on hotshoe, set as MASTER, but Manual 1/128
camera - bulb, REAR

no lights in bathroom with mirror

(previously)) as mentioned it is flashing upon when I initiate. But I reset it to Manual and it works as it should
Initiate, shutter opens
Then released the release, and the flash DID flash and DID show up in the photos (ie in the photo you can see the FLASH in a full FLASH)

I took about 20 shots varying from about 1 sec to 20 seconds.
in ALL of them the flash was in the picture for REAR


I sold my SB-600 about 2 weeks ago .. so I only have the 800 and 700 to test. I figured the 800 was the same generation as the 600 so the best to test with.

 

[astroNikon]

I just redid the test since I understand it better now
and I was able to replicate it as it should be

Flash flashed at the end of the shutter release only
and it showed up in all the photos
from 1/xx to about 20 seconds

 

[epp_b]

And that was in bulb mode every time? Is there anyone here with an identical setup? (D7000 + SB-600)

 

[astroNikon]

yes, BULB mode every time
just stood in a dark bathroom holding the release down for various times.

 

[epp_b]

yes, BULB mode every time
just stood in a dark bathroom holding the release down for various times.

Well, that's kind of frustrating :\ (for me)

I wonder if it made any difference that you're using an SB-800?