b-r-e-a-t-h-----s-l-o-w-l-y, we're almost there! The 60/40 is a two head [lamp] flash? Okay, larger [60] dedicated as main with a [40] secondary lamp used as fill....... sounds like wedding stuff to me, but it will work, however, a little modified over my initial opinion.(posted 8805 days ago)Using your last numbers:
#1) yes, right, do you see the light now...... go towards the light Shawn....
#2) yes, main light is the one casting the shadow, but we get F***'d- up with this two headed flash [more appropriately two tubed, right?]. You can only have one [meaning ONE flash tube/tungsten/HMI or whatever bulb/lamp] serve as the MAIN light source. Even though they are really really close to each other, you are going to get dual shadows, unless you put the entire head into a softbox or umbrella and then both heads will be combined into one source [assuming they are pointed into the device in the same direction]. If you leave the unit as is [at least from my new understanding of what the 60/40 is] you will get two shadows no matter what. Is it possible to turn one of the tubes off [preferable the 40] and get a higher single tube output? Probably not, but all is not lost, read on...
Ratios are your friends, embrace them, know them, and love them. Knowing the different types of modifiers allows you to alter the look, or create a look, for an image, and once you have a firm grasp of how to do it "right", then you can set forth to break the rules. Knowing ratios let you set mood with any kind of lighting equipment. Hang in there!
Given the equipment at hand, use a single, bare tubed flash head as your main. Even if it isn't your strongest output head. Think "sun" here, one blazing single light source. How'd that F***ing umbrella sneak back in there on the main light? I thought we were clear on this, BARE TUBE, OPEN FLASH, NO MODIFIERS. Do you read me mister!
The main will set the next heads output level. If the main is at f/11, you should be able to get NO ancillary shadow at probably f/5.6 [minus 2 stops] for a fill light reading. At no time are we dealing with any other readings [like combined --- jeesh, where did that come from ;O)]. Main=f/11, fill=f/5.6=you'll be close; fill @f/4 would be better [assuming 100iso film].
Uh, lets see, what else, oh ya, as to your metering technique. I know you are pointing the diffusion dome of your flash meter AT THE LIGHT SOURCE, right!?! You need to be very careful when you measure your lights, to make sure that you are only reading the intended individual light, not COMBINED measurements. If your main light reads f/11, that's all you care about, you set everything from that, including your camera. Your fill light should be placed at such an angle so as not to compete with the main lights side [if you will] of the contribution to illuminating the model. Okay so far? For a model reclining on a couch, place your main light at 6 feet off the floor, camera right, 4 feet away from her and pointed at her [?] head, it should be pointed downwards at a 45* angle. Your fill should be to camera left, at about 4 feet off the floor, and say 45* pointing in from 8 feet away. No fill light will spill over onto the main light side of her face. The main light is a bare tubed flash head [we want a focused, spot look] and the fill is a broad beamed, soft raking light, so we will use an umbrella set two to three stops under the base exposure [main light reading]. Now, set the cameras exposure to accomplish what you want. I shoot tranys almost exclusively, so if I want a REALLY dramatic look, Ill set the camera to the main lights base reading. By opening up the aperture, I am letting in more light, and increasing the reach and effect of my light. I will get a larger penumbra with larger apertures. Whoa! Where did that come from?!? Yup, its true, and you can use it to good effect too. If I want to shoot a really dramatically lit shot, Ill get out all of my grid- spot attachments, crank all of the power pucks up to full-tilt, and shoot at the smallest aperture I can. There is very little bleed over between the different spots of light when you do this. The edge effect is very sharp [small penumbra]. BUT, on the flip side of this is you. Your equipment is too puny to allow you to shoot at f/16. At the wider apertures that you will be shooting at [f/5.6 or f/8] you will have to be very diligent in controlling your spill [use gobos], but no matter what, the penumbra will be larger than when shooting at f/16 with a similar head.
Sorry to keep brining up new things, but to fully grasp the entire theory of lighting is beyond a couple of paragraphs. I think that we are working through multiple problems here, but hopefully getting closer to what you want to get. I would suggest checking out the Pro- Lighting series by RotoVision. They are really fairly well done books, and are up to date. BTW, a couple of my pics will be in two new volumes coming out any day now, so I have a vested interest in there use!
This sucks trying to type what would be immediately explained with two or three pics. Arg! Let me know, and keep me posted.
As a final method of illustrating what to do. Given my equipment, I would set up a grid spotted main light, with fill from an Octabank. I'd probably through in another grid spot as a hair light for separation, but would largely rely on the Polaroids for final tweaking. You have to get roid capable ASAP.
Bet you're having fun now!! I can smell the smoke from here!!