John, the Cuddeback has a built in Battery Load Test. In the Exif Data from the picture it records BL and BP. What do these relate to?
View attachment 25527
View attachment 25528
View attachment 25529
[/
View attachment 25530QUOTE]
BL is an instantaneous load test of the battery voltage in mV at the moment the picture was taken. In the case of any J camera, a K camera with the dual flash module, or a G camera with the dual flash module the load on the batteries at that point in time is the load of flash plus the smaller load from the normal operating load of the camera. In the case of a G or K camera with a Powerhouse flash the load on the batteries at that point in time is the load of the super capacitors recharging (
if any) plus the normal operating load of the camera. It's important to keep in mind that the intermittent load on the batteries due to capacitor recharge with the Powerhouse flash is much more than the load due to the shot to shot continuous pull on the batteries of a standard flash module. The Powerhouse flash makes up for the intermittent big hit on the batteries (as much as 0.4 volts) by going on after recharge with a series of shots that draw no flash power from the batteries... instead using the stored power in the caps to operate the flash. The beauty of the Powerhouse flash modules is that not only do they supply 3X the light over a standard module but they do so in a full and consistent way from the first shot on a set of batteries to the last gasp. This is not so with the standard modules in that they supply power to the LEDs directly from the batteries and will consequently dim somewhat as the batteries deplete. The consequence of this dimming over time is that the camera will have to compensate for less light by lengthening the shutter speed (more motion blur) or upping the ISO value (more noise). You can tell when your flash is beginning to dim by watching the
IR% in the comments string of the exif data... the value will show less than 100%. At what value this brownout of the LEDs becomes unacceptable is an issue for each user to determine for himself. The Powerhouse module on the other hand will be absolutely consistent from day one forward on a set of batteries. So in the case of the Powerhouse flash module beware of the temporary heavy drops in the BL readings on an individual picture as they are just indicative of the caps recharging at that one point in time. Take you reading of battery voltage from pictures that show the high values in between the nosedives.
BP is a nominal estimation of battery power remaining as a percentage. It is keyed to an alkaline battery chemistry and is directly correlated to the BP reading. On a 6 volt system it would register 75% if the BP is 5599 through 5350 and 50% if the BP is 5349 through 5150, and so on. Since it is keyed to alkaline batteries it will be even less reliable as a percentage with lithium or rechargeable chemistries.
