digital f717 with strobes--too bright!!??HELP!

[kboy2k]

hello all--i am a newbie--taking portraits against grey backdrop-with sony f717 5mp camera-have external 2 strobes-britek ps200 with reflective umbrellas--i have hotshoe hooked to sync to fire strobes-on camera flash does not fire--only strobes--always pics aare way too bright/overexposed/-almost all pic is whitewashed out--tried setting to aperture priotiy mode-no aperture worked atll-f8 to f2.0--still to bright because shutter is auto set her in this mode--also tried shutter priority mode--no luck-even if shutter ia at 1000 fastest?--because apeture is set auto in this mode-so finally tried manual mode--adjusting both apert. and shutter--only shutter that comes close to working is 1000-fastest-why is this necessary--and very few apertures work her either- f5.6-6.3 or so--seem to work ok--but this defeats my portrait setting of blurring the backdrop at f2.8 or so-which is how I prefer to do portraits!?please please help- I am shooting full body portraits at 10 feet or so--even if light are at 1/2 power my photos arre still too brightor I guess overexposed is the term when I see them on my lcd--i mean real bad-like almost totally white.--i can use just the modeling lights as"hotlights"-and cut off the strobes--and adjust to f2.8 but that defeats purpose of buying the strobes--i must be doing something wrong here--just cant see why shutter needs to be at 1000 for proper exposure???-please any help is deeply needed.-
i checked my camera setting when i have it set to manual and shutter is at
1000 and f5.6 or 6.3 or so--i did not think to check iso--however i did-and
camera iso setting iso is set to "auto"--whatever that means--no idea what
it really equates to once the shutter is pressed???--will try
setting iso to100 or 200?? --also has options for 400
or 800 iso--dont know what else to do-help a newbie out here-what shutter
speed shoudl i use (and what iso if i want my f2.8 aperure--only reason i
like the f2.8 is to blur the backdrop just a bit--not a huge deal but -the
brightness is--iso is film speed right-=100-200 iso=shots for still or non
moving objects or dark lighting?--and 800 iso is for fast action or day
light?--sorry -so confused--thanks for any help guys-- i can use all i can
get.--also tried setting iso to 100--this does not help either????

[JCPhoto1]

You really know how to ask a question. What you’re trying to do is a complex operation with limited equipment. Your camera only has a range of f/2 – 2.4 to f/8. You also have lights with limited control. The best way to answer your question is to list what you need to do to take a studio type shot like this. It would help to have a meter to read your lights but it can be done the way you have been doing up till now but it is trial and error process. First you would set up your lights relative to your subject. Then when standing by your subject fire your lights and take a reading with a flash meter. You would have already set your ISO setting in the meter. When you read the flash the meter will give you the F stop that will produce the best exposure. At that point the shutter speed is not too important except to stop any motion. If you’re using a speed light there is a sync shutter speed specific to each camera that you would not go over. You would have to look that up in your manual. If you’re shooting with mono lights you can go higher than the sync speed usually with no problems. For portraits a shutter speed of 125 to 250 is enough to freeze any motion of your subject. Ok, that’s all in a perfect world. Your setup has restrictions that you’ll have to work around. First an f stop of f/2 is going to give you a very shallow depth of field and doesn’t seem to be necessary for what you want to do. I would go to the other end of the f stop spectrum and try shooting at 5.6 or f/8. Move your subject away from your background and see if it has the blurring effect you need. If not go to a bigger f stop until you get the results. Also use the lowest ISO you can and take it off auto. You can also move your lights back more or get neutral density filters to go over your lights. They are available in different densities and can reduce the output by a few f stops to help adjust the light down. If your umbrellas are shoot through use them that way. Everything I’ve said so far is geared to lower the light output. That will bring you into the range of light to get a proper exposure. I hope this helps because this is a simplified answer to a question that has a lot of variables. Try what I suggested and see if any of it helps. If not tell us what happened and we’ll see if there are any other solutions to the problem. Good luck!

Jim C