Also consider 300Rx for this purpose. It goes down to 9WS. I am using Elinchrom exclusively running Micro packs of 3000WS and 6000Ws. With Aptus 75S on Rz67 and dedicated 6000Ws pack with dual head I can only get F8 at full power ( ISO 50 ) on Octabank for full body shots.
On the other hand the minimum setting of 125Ws on 6000 Micro Pack and 66Ws on 3000 Micro Pack are useless for bare reflector or Fresnel as they are way to bright for the rest of the set up.
When I recently bought my Nikon D3 I quickly realized that I do not have any lights in the studio besides HMI's to use the camera with. Even the 300w modeling lights are too bright for their ISO 200 when I want to shoot wide open at 1/250.
9Ws on large Elinchrom Fresnel Spot is good for MF but way to bright for D3.
1200W HMI's are not enough for Aptus/RZ for Octabank even at 1/60 but on D3 85mm at 1.4 they are pushing the shutter to the absolute maximum.
To be able to lit properly you have to have the complete array of lights as the 7 stops of adjustment on most modern packs will not cover all the differences between modifiers.
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