OK I see that perhaps the information was not very clear since I just tried a test as per Hasselblad today. Using one strobe and a reflector I shot a series of tests starting at a shutter speed of 1/60 at f11 on all the shots based on a meter reading. The light source is the Elinchrom EL 500 shot into the Elinchrom Octa just outside of camera range. It turns out, every exposure shot at 1/500th was darker than the others starting at 1/60. Looking at the histograms on both the CFV and in Phocus, I can see it creeping to the left after each shot and the biggest jump to the left was at 1/500 ( the series was 60,125, 250 and 500) The lenses used were the 150 CFT, 250 CFT, 80 planar and the 40 IF Distagon(which is brand new). Tech support at Hasselblad thought that the shutter needed service on my 150 since this was the lens I described to him, but if the same thing happens with all these lenses, I have a hard time blaming each lens. The CFV II is set to exposure time to <1/8 sec. but it did the same thing at a higher setting. The flash was triggered with a Radio slave connected to the lens and no connections are being made between the camera and CFV. I even tried triggering the flash with the sync cord connected directly to the lens and the same thing. So basically, one should not use such a fast shutter speed with strobes? In my setup, there is a lot of light entering through windows during the day, so I increase the shutter speed to keep them from affecting the exposure etc. My understanding was that these lenses will sync at any shutter speed. Any thoughts would be greatly appreciated.
See my answer to your PM for a detailed answer. Here is more on the subject:
You have answered your own question, and it has nothing to do with your camera/lens equipment. It is about lighting.
Shutter speed will have no effect on the strobe exposure. The longest duration of your strobe is still faster than the maximum shutter speed on your camera.
However, shutter speed
WILL have a DIRECT effect on any ambient present in the scene because ambient is a constant source of light, not a brief burst. So, if you start with a fixed aperture, and adjust from 1/60 shutter in steps to 1/500, the ambient part of the scene will underexpose in steps.
If the studio shooting environment was pitch black, with no ambient light at all, using the same f-stop, you would see little to no variance in exposure between 1/60 and 1/500 using only the strobe.
The way to light in a studio with ambient present, is to predetermine what f stop you need for depth-of-field, set the shutter speed at maximum to eliminate as much ambient effect as possible, and adjust the strobe output controls up or down to expose the subject properly. You do not alter the shutter speed or the aperture. If you change the aperture, you will than have to change the output of the strobe. Stop down the aperture one stop = increase the strobe output one stop ... etc.
When outdoors in extremely bright sun, it often is nearly impossible to eliminated all of the ambient. The way that you control that brightness is to use the faster shutter speeds combined with stopping down the lens aperture to expose the background the way you want it to look, and then adjust the output of the strobe to add light back onto the subject.
The Hasselblad V camera provides 1/500 sync verses 1/125 of focal plane shutter MF cameras ... which in turn is 2 extra stops of shutter speed to use for controlling bright backgrounds. The H camera with 1/800 sync speed has a bit more.
In extremely dark conditions, you can use a very slow shutter speed to open up badly under-exposed backgrounds and adjust the strobe to light the subject properly. This technique is called "Dragging the Shutter".
-Marc
