External battery pack for A6000

[AK47J]

Last summer I did some time lapse videos. Could only manage about 2.5 hours on the Sony battery and less than 2 hours on a third party battery.
I want to try some more time lapse and star trails, and would like a longer run time than 2.5 hours.
This is what I came up with. Parts arrived today, so I have yet to experiment.

SM-N910V    ---    5mm    f/2.2    1/20s    ISO 250

 

[chrid]

Cool, looking forward to the results

 

[WNG]

Check out this thread....

https://www.talkemount.com/threads/12343/

 

[AK47J]

That is pretty cool. I already have a pile of Eneloop Pro AA batteries, so I went that route instead. The 6XAA battery holder was only $6 shipped.

 

[WNG]

Cool! Where did you source the AA kit?

I happen to have the bike lights, so I focused from that end.

 

[AK47J]

Cool! Where did you source the AA kit?

I happen to have the bike lights, so I focused from that end.

I got the A/C adapter kit and AA battery holder on Amazon. I can post links if anyone wants

 

[Kirkp]

Links would be great if it works well for you.

 

[AK47J]

Battery holder
http://www.amazon.com/gp/product/B00HGAL0L0?psc=1&redirect=true&ref_=od_aui_detailpages01

A/C adapter
http://www.amazon.com/gp/product/B0083EQS3I?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00

 

[Kirkp]

For anyone else planning to do this I thought I'd point out it's probably best to always use eneloops, not alkaline batteries. 6 Eneloops at 1.3V are 7.8V, close enough to 7.6V that the camera expects. Fresh alkalines would be at least 9V.

 

[AK47J]

Used this setup a few times with mediocre results. Using 6 freshly charged eneloops results in the camera reporting 50-65% battery. So I tried 4 eneloops and two fresh alkalines = 100% yay. Did a 2.5 hour time lapse, camera said 50% battery at the end. Seemed promising. Did a 2 hour time lapse, camera said 25% at the end ... ? I did a couple more around the 2 to 2.5 hour, with widely different and disappointing final battery percentages.

I have another idea, need to order a few parts/gizmos, I'll keep you guys posted.

 

[Kirkp]

I realized my comment above considered only nominal voltages of the cells. To do this right, one needs to consider voltage curves of each battery type. I'll be interested in your next iteration.

E.g., eneloop:

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Lithium-ion (per cell):

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There might also be some regulation circuitry in the battery packs.

 

[Ad Dieleman]

Used this setup a few times with mediocre results. Using 6 freshly charged eneloops results in the camera reporting 50-65% battery. So I tried 4 eneloops and two fresh alkalines = 100% yay. Did a 2.5 hour time lapse, camera said 50% battery at the end. Seemed promising. Did a 2 hour time lapse, camera said 25% at the end ... ? I did a couple more around the 2 to 2.5 hour, with widely different and disappointing final battery percentages.

I have another idea, need to order a few parts/gizmos, I'll keep you guys posted.

I think the camera's indication of battery charge is completely off when you're using anything else than Lithium-ion batteries: the percentage indication is designed for Li-ion batteries and the discharge voltage characteristics of either alkalines or NiMH rechargeables are very different so it could well be that the camera indicates a low percentage while the NiMH batteries are still useable; using alkalines with their much higher starting voltage will surely make the camera think there's a full battery. In other words, just ignore the percentage. NiMH batteries easily have a capacity of 2000 mAh these days so your battery pack should last roughly twice as long as the Li-ion battery pack. Need more? Use D cells .

 

[AK47J]

I think the camera's indication of battery charge is completely off when you're using anything else than Lithium-ion batteries: the percentage indication is designed for Li-ion batteries and the discharge voltage characteristics of either alkalines or NiMH rechargeables are very different so it could well be that the camera indicates a low percentage while the NiMH batteries are still useable; using alkalines with their much higher starting voltage will surely make the camera think there's a full battery. In other words, just ignore the percentage. NiMH batteries easily have a capacity of 2000 mAh these days so your battery pack should last roughly twice as long as the Li-ion battery pack. Need more? Use D cells .

True. But if the camera "thinks" the battery is drained it will shut down, even if there is ample run time in the batteries.

 

[AK47J]

Got the parts today. The clear project box (not pictured) that I ordered is much bigger than I need (because the description of the voltage regulator was incorrect). Hope to give this setup a run soon.

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[ShaneD]

Thank you for the information. Pleased keep us updated on the latest version. I'm getting ready to build one for A6000

 

[Tony Burns]

Your post reminded me of my own desire for a continuous power supply to my a6000, and when I went searching around I came across the Sony ACPW20 (dummy NP-FW50 battery with an AC adapter), which I think I'm going to pick up now. One nice plus to the ACPW20 looks to be that the camera actually knows that it's on external power when you're using it, so no strange battery capacity indications.

 

[chalkdust]

I have not used one of these, but am interested in knowing how it works for you. It seems like it will support your studio, product shots well. I do not do studio work so am more interested in a mobile solution. Anyway, let us know what you think of it after you have used it.

 

[sam]

I love these DIY projects.
I have built many of these types of units, starting back in the early '90s, for my Sony FX420 camcorder. Then when I got my Minolta 7Hi, and also for my Canon DSLRs.
I have also thought about one for my Sony NEX 5R, and now here is a thread on just that. Thanks for all the info on part sourcing.
It might take a while to build, as I just got 2 new third party, high amp batteries, so now have 3 batteries for the camera.
As I am interested in starting some time lapse photography, I think I will hurry this one up, and go for a test drive soon.

Thanks