@feha I understand the parallel with two batteries. My question is much more simple and I'm just really double checking what I want to do.

Take 1 output (pos and neg)_ from the idx battery which is rated at 14.8 v. Take the positive and negative out and split each so their are 2 negative line/connection and 2 positive line/connections. Then put a switching regulator on each set. One for 8.6v and one for 12v. Gh2 and monitor.

@feha Thanks for confirming what I thought I knew.

Today, using a 8.4V Tennergy 5000mAh battery (less than 40 dollar battery), I was able to duplicate what others have done. Running Sanity v5 24H mode all manual, I was able to record continuously for 7 hrs:54 minutes (I stopped it at 8.46V). I recorded to two 32 gb cars at 30mb/s. I'm hoping I can get 4 hours or more on the IDX battery while powering the camera and a SmallHD 4" monitor. The 7:54 hrs was done in 85 degree bright sunlight with an umbrella over the camera for 4-5 hours of the almost 8hrs.

Hello, This looks like a decent price for everything. http://www.ebay.com/itm/External-Rechargeable-Battery-for-Panasonic-GH2-Extended-Video-8500mAh-DMW-DCC8-/180884594186?pt=US_Rechargeable_Batteries&hash=item2a1d8fde0a

I don't know too much about powering issues, but to me it looks great.

@Alfaerik you can get those on ebay seperatly cheaper.go few pages back in topic.

@jakef i acctualey got those but have to make DIY adapter cable before i can test.however 9v cable does not seem to be very snug on pin. plug sticks out quit far.is it same on yours?

@hank

It's secure but does stick out I'm tempted to open the battery and hardwiring this

http://www.ebay.co.uk/itm/DC-Jack-4-0x1-7mm-Power-Right-Angle-Plug-Connector-with-Cord-Cable-1-1-Meter-/290721782186?pt=Laptop_Adapters_Chargers&hash=item43b05e59aa

or this but cut off the 5.5mm x 2.1mm side to expose the wires then hardwire or attach a 90 angle male 3.5mm x 1.35mm tip as in my picture.

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=Blue+50cm+AC%2FDC+Curly+Coiled+

or a lead with a 90 angle male DC 3.5mm x 1.35mm tip from the battery

I've got to finish my cage now as its very awkward to manage all the bits.

@hank not yet, i'm also interested in how long it would last with both connected.

Hey- I accidentally started a new thread instead of posting here (I guess someone can delete my other one about external battery powers). (EDIT: It looks like Vitaliy already closed it as I was writing this. Excellent response time, sir!)

I'm really interested in those Chinese CCTV batteries, but I need something I can get in the next 2 weeks, and shipping from China is too unreliable for me to get and test before an upcoming shoot. So, I've done some homework and found the following options:

http://www.bhphotovideo.com/c/product/618847-REG/Tekkeon_MP3450I_myPower_ALL_Plus_MP3450i.html/ I've heard confirmation that these work well. But at $140, it seems kind of pricey to me.

http://www.amazon.com/15000mAh-External-Motorola-Portable-eletronics/dp/B0067XMPNY/ref=pd_ybh_14 This one looks interesting- has an LCD display. Not sure if that doubles as a battery life indicator, but the price is nice.

http://www.amazon.com/EZOPower-High-capacity-Rechargable-10000mAh-Blackberry/dp/B005XQSN9G/ref=pd_ybh_11 I like this one simply because it is Amazon Prime compatible and has some reviews. Its less capacity than the previous option, which had 50% more than this.

Or should I just go with the cheap RC battery thing? I tell you, the things that worry me about the RC route is that the voltage isn't regulated, so you can easily get a spike of 10-11v when you first take them off the charger. It seems like most people have been using that without a problem though.

For $50, with a charger and multiple tips already included, are any of the options I posted above worth trying?

Scratch that (sorry for all the flooding in this thread, I'm posting stuff as I find information), the 10,000mAh are only at 3.7v. Which is still good, but not great. At 9v, that's just over 4,000mAh, or roughly 3-3.5x times the standard battery.

Now I'm back to considering this one as my best bet: http://www.amazon.com/15000mAh-External-Motorola-Portable-eletronics/dp/B0067XMPNY/ref=pd_ybh_14 Still rated capacity at 3.7v (which threw me off earlier), but seems to be higher capacity than previous one @ 15,000. At 9v should yield a healthier 6,100mAh (approximate), or roughly 5x times the capacity of the OEM battery. That's more like it. It has a built in LCD to set the voltage as well as a meter displaying capacity remaining (which is nicer than the chinese CCTV ones IMO, where you have to keep track of your own mileage).

I've never heard of this battery company that makes them, but it seems to be a variation of this one:

Unless anyone can find something I'm missing here (as to why it might not work) or suggest something better, I think I'll purchase this one tomorrow.

Any opinions/advice on the matter?

I'm currently using without any problems these 2 items together: http://www.ebay.com/itm/DC-DC-Converter-Boost-Buck-Step-Up-Step-Down-Voltage-Module-3-5-28V-to-1-25-26V-/110773899595?pt=LH_DefaultDomain_0&hash=item19caa3914b and http://www.ebay.com/itm/6400mAh-Rechargeable-8-4V-Battery-P7-XM-L-T6-LED-Bicycle-bike-HeadLight-Headlamp-/250907264154?_trksid=p4340.m185&_trkparms=algo%3DSIC.NPJS%26its%3DI%252BC%26itu%3DUA%26otn%3D5%26pmod%3D170710221252%26ps%3D63%26clkid%3D7690970456910103103#ht_4297wt_952

although, on second thought I would have opted for this battery: http://www.ebay.co.uk/itm/New-Black-5V-9V-12V-3-in-1-DC-Rechargeable-Li-ion-Battery-For-CCTV-CAM-Camera-ep-/380435831423?pt=UK_ConsumerElectronics_Batteries_SM&hash=item5893be1a7f if they only would ship to Italy.

This is only good for someone like to use battery grip. Battery grip is little bigger than camera. I'm using converted Nikon D300 battery grip with 8AA battery adapter comes with it. Gut it out and leave only + and - terminal for D300 battery grip. Get Panasonic battery adapter or cheap Chinese battery and gut it out and use only +&- terminal to make a connection. Be very careful when you work with battery gutting way. Check and recheck to make sure you don't smoke it! I use Sanyo rechargeable and right after charge, only 7AA +dummyAA works. If I use 8AA, voltage is too high, close to 11V. There is no cable dangling and not get in my way of using GH1/2. No voltage indication but it will last you more than a day, especially you don't use EV.

Update: I got the ATC battery pack today similar to the one in the video linked above (nice, ordered it Friday, arrived Monday!). Plugged it in, seems to power the device just fine with the soldered-on plug I made to the DCC-8. I don't see any way to change the polarity of the battery pack yet, the tips just are whatever they are. So, I guess its a good thing I had already snipped off the proprietary Panasonic plug for a standard sized plug and polarity (+ in the center).

Charging it up now so I can put it through a stress test later. So far so good!

Only question left is how/where to attach it... I'm likely shooting with a Manfrotto 561HDV instead of a shoulder rig, so I have to figure out a good place to attach it. Maybe gaffer's tape to the monopod?