Before using the Comer 1800 for an extended period of time, I decided to conduct a simple battery test by connecting a relatively new and authentic Sony NP-F970 (a few months old, w/less than 10 recharge cycles) and turn on the Comer 1800 to full power to see how long it would last. The room temparature was about 24 degrees celcius.

The Comer brochure says that the light should last approx. 140 minutes on an NP-F970 battery at 25 degrees celcius.

Well much to my pleasant surprise the light ran 188 minutes (over 3 hours!) before shutting down. Thats 48 minutes longer than the advertised specs! Also, the light did not appear to change color, lose intensity, or flicker at anytime during the test (keep in mind that this is truly subjective as I don't have a light meter to support this), it simply shutoff when the battery was fully drained.

I am curious how much longer it would run on one of the newer Lenmar LIS-970P batteries which are rated at 7800mAh as opposed to Sony's 6600mAH rating. I'm also curious if anyone has tested the NP-F770 under similar circumstances, as that would be a lighter solution than using the 970 and if it ran 2 hours or more, would probably be all you need under most circumstances.

I thought I had read somewhere the 770 lasts 90 minutes, but I don't remember where I saw that info, and it might have been regarding the comer 900.

I'm also curious if anyone has tested the NP-F770 under similar circumstances, as that would be a lighter solution than using the 970 and if it ran 2 hours or more, would probably be all you need under most circumstances.

I'll let you know after this weekend. That's the battery I plan on using

I shot this weekend using the Comer 1800 for the first time. I have to say, what a great light to have. The room was pretty dark and the light really covered the edges nicely. At one point I had to shoot from approx 15' and I had good light coverage. I'm not sure how durable it's going to be but it had good light. I used the NP-F770 and it lasted all day. I used it during the bridal prep and the the party. I stuck a couple of batteries on the charger and went to sleep so I forgot to see how much time was left on the battery. Anyway, it performed better than expected.