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1 hour ago, Gabriel Devereux said:

I don’t mean to be obtuse but, that isn’t my question. 
At what point is a sensors capacitance reached?

A photo site well doesn’t exist -
A photodiode has a depletion region. A photo site is the area of the photodiode plus circuitry.

In terms of managing capacitance with tiny readouts are we talking about actual latitude of the analogue ‘wire’ the photo sites ‘drain’ as in the depletion region itself of a photodiode or the readout time in relation to the shutter.

I should also add a photo site doesn’t store photons… it’s a common misconception. Instead electrons absorb the magna of energy from the incoming photons and generate a current.

I'm quite sure what you mean by sensor capacitance. Do you mean well capacity of the photodiodide?

8 hours ago, Gabriel Devereux said:

As always your posts are brilliant and enlightening - 

May I ask, what do you mean in terms of managing capacitance? Is that in terms of storing charge at the photosite itself? The MOSFET power follower? The impedance prior to the drain causing noise? Or the actual read-outs running to the column amplifiers and then to ADC?

Thanks

G

There are two pathways from the dual gain sensor. Every photo-sites output is boosted to a target voltage level before it hits the ADC. The voltage level plus the well capacity determine the saturation point of the photo-site. The ADC matches the range of the incoming signal.  In dual sensors, a separate pathway with lower than  usual  amount of gain is added. The lower amount of gain increases the saturation point(brings back the highlights). The difference in gain determines how many stops can be added to the top of the dynamic range of the dual gain system.  The photo-site itself has a limited dynamic range, but this engineering trick acts like you are combining the readings of two photo-sites at the same location. It also doubles the processing power needed since you are combining 2 frames to get one.

I have some 1x1 lit panels.. you can buy as extra,s plastic type diffusers that slide into the front.. trouble is the actual light source remains the same size,so its not really enough to soften the light out ... unless you have a very small target object..

 

I hang a small silk 3x3. from a light weight boom arm.. about 1 metre in front of the light.. this will soften it enough for faces .. as long as your close enough to the subject..

Thanks for the replies, David and Robin. I have frames, but I am looking for better control over spill. Hence the barndoors and putting the diffusion close to the source. I am experimenting with falloff on sources very near to the subject, so the small size of the 1x1 panel isn't a problem.

Which diffusion material would do a better job, 1/4 white diffusion or opal frost?

What is the best diffuser to prevent multiple shadows from a 1x1 led panel? I want the diffuser close to the lights so I can use barndoors.

Thanks for your helpful reply

D,

the avenger stand is fine for an 8x8. many reasons to go above 14'? you never know is the Challenge to that question.

Examples: diffusing raw sun through a second story window. diffusing sun over a tree branch. diffusing a light raised over a truck. bouncing a light because production won't rent a condor, the angle of the sun is just so that the frame has to be high to catch the light and be out of frame.i can go on.

 

I found when i owned gear that a 2 riser combo stand was almost worthless. nothing is more demoralizing than raising a light on a stand and then having to exchange stands because you needed another foot out of the stand. 3 riser combos are mandatory on a grip truck.

Thank you for your helpful reply

If I put wheels and a 4.5 griphead on this stand http://www.bhphotovideo.com/c/product/600650-REG/Avenger_A1045CS_A1045CS_Steel_Combo_Stand.html would it be a decent choice for an 8x8 frame?

I'm gathering that the height of the stand isn't as important as it's weight and footprint. Are there many reasons you would go beyond 14' in height for a 8x8' frame?

What height of combo/rollers would be optimal for an 8x8' avenger frame. I have 2 11 foot combos, and I was wondering if 14-15 foot rollers would be better.