This is a flash sync problem, correct?

[lacy_dillard]

I gave in and bought a flash (a Vivitar 2800) which I'm hoping to use

for both indoor fill, and low-light concert photography. I went over

the directions and searched for fill-flash tutorials, but eventually

decided to shoot a roll and try to decipher the results. I'm using a

Kiev 60 which has a 1/30 max sync speed, and the film was Portra 100T

(tungsten balanced). I rushed home to scan the film, and it took me

two shots to notice the problem ..<br><br>

<img src="http://www.iamadot.org/pictures/lacy/1107.jpg"><br><br>

As for the photo in general, the flash seemed to work pretty well.

Picture it at four o'clock just out of the frame. I don't know what's

going on with the blue reflection on her sleeve .. from the stove

hood? My problem is the very left edge of the frame where there is a

part of the shot underexposed. I honestly didn't notice this until I

opened the tif in Photoshop.<br><br>

<img src="http://www.iamadot.org/pictures/lacy/1108.jpg"><br><br>

Excuse this! It's not a very good shot, and normally I wouldn't show

it to anyone, but the underexposed area is back and even more apparent

here. It turns out that the entire roll is like this other than the

very first shot. I remember taking them at 1/30 but I could have made

a mistake. I'm planing on trying another roll tomorrow but at 1/15,

1/30 and 1/60. I hope that I just accidentally moved the shutter to

1/60, but the exposures look the same to me.

[bill_sooby1]

Yes, I think that you do have a sync problem but not because you have set the speed to 1/60. I think that if you had done that then the underexposed area would be noticeably bigger. I'd guess that the second curtain of the Focal Plane shutter is starting to move a fraction of a second too early, or equivalently, the flash is being triggered a fraction to late.

 

I'd do a test to check - use cheap film and D&P. Using a fairly light background (so you can see underexposure) in a fairly dark environment (so that the flash is providing nearly all the light) take pictures of the same subject at 1/8, 1/15/, 1/30, 1/60 and 1/125 sec. You should go from no underexposed area, to a very noticeable taking up most of the film area. If there is an underesposed area when shooting at 1/30, then the camera flash sync will need to be adjusted.

[steve_levine]

The reason there were no "fill tutorials",is that a V2800 is a rather limited piece of gear. It has 2 ranges of "auto" flash apertures,and a manual setting that dumps everything. In order to use fill flash correctly,you must reduce the flash level in relation to the ambient light level. In other words the flash isnt the main light, in a fill scenario. The V2800 has no power adjustment per se. Changing the ISO simply moves an indicator to the suggested aperture,it does nothing to reduce or increase power.

The only answer is to shoot at an F stop smaller than the flash is firing at.( lens is set to F8,flash firing at F2.8)This method works with subjects of average brightness ranges.The other thing to do would be to meter the manual flash, and reduce it via gel neutral densiity filters in front of the flash head.This would lower the flash power to fill levels.

[steve_levine]

BTW,you can check sync w/o film.Open the camera back and fire the shutter and flash at differing speeds.You will then be able to see where the shutters are when the flash fires.

The "blue" reflection is daylight coming in the window,and exposing on tungsten film.The answer here would be to shoot daylight film,or place a 85A filter gel over window.

[bill_sooby1]

Steve,

 

I wonder if the eye would be able to spot what looks to be only a small error in flash syncronisation? I think that you would have to use film in order to pick up this sort of problem.

[ronald_moravec1]

Put a business card over the film gate leaving a small gap at the edge. Fire the flash and see if the flash is visable thru the gap. Repeat for the other side.

 

If it is a leaf shutter, just look thru and check to see the flash is visable.

 

I think the problem is the one edge did not develope properly, such as would be the case for insufficient solution in the tank.

[rwdocherty]

Is your Kiev 60 internally flocked? The unmodified ones used a reflective black paint in the mirror box and underside of the mirror. A flash would add to the flare caused by the boneheads using reflective paint inside the light path to the film. A synch issue would probably appear more like a partial frame exposure.

[rwdocherty]

Sorry I didn't read before posting. The "blue" might be due to reflections. The left border looks like a synch error. Is this Kiev from a Kiev rebuilder like Arax, KievUsa, etc. Shutter speeds are notoriously iffy straight from the Ukraine...