[MJKoski]

Recent cold temperature outings with K-1 have revealed kind of low battery life.

So, Pentax could be the first to do something really useful - real Battery Grip. Make it so that it offers 15 000 mAh capacity with solid integrated rechargeable battery. Standard dummy battery inserts are clumsy and dangerous when moving around in the dark with snow shoes or skies.

It could sell rather well to northern barbarian tribes.

[BigMackCam]

I've often wondered why the camera manufacturers don't do a grip with dedicated high-capacity battery for higher-end cameras, as there's a lot of space inside the current designs that is effectively wasted.

At least with Pentax, we have the camera battery in place and two extras in the grip... On my Sony A7II, the grip interface plugs in where the camera's battery would normally reside, and just two batteries are in the grip...

[honey bo bo]

So, Pentax could be the first to do something really useful - real Battery Grip. Make it so that it offers 15 000 mAh capacity with solid integrated rechargeable battery. Standard dummy battery inserts are clumsy and dangerous when moving around in the dark with snow shoes or skies.

..........and not explode in your pocket!

[MJSfoto1956]

I've often wondered why the camera manufacturers don't do a grip with dedicated high-capacity battery for higher-end cameras, as there's a lot of space inside the current designs that is effectively wasted.

That would be Nikon.

M

[BigMackCam]

That would be Nikon.

Our expletives filter hasn't started working yet, clearly...

[biz-engineer]

Two fully charged Pentax branded battery last approximately 12 hours with K1 switched-on 100% of the time, that's what I get. With 6x 2500 mAh fully charged in the grip, that's about more than 14 hours continuous power. The grip is delivered with two parts that slide in, one for D-LI90 , one for AA. When carrying a grip + the extra 6x AA block, that would provide up to 20 hours of continuous K1 power. In Live View, the duration is less then half, 2h30 max continuous for a fully charged DLI90. I guess the problem isn't really battery capacity but performance of batteries at low temperatures, especially if not fully charged before use.

[MJKoski]

At -20C I get about 50 shots with live view. Carefully composed that is. Exposure times can be anything from one second to 5 minutes.

Or, 200x30 second continuous series without liveview.

A7r2 gave me about same battery life but it plummeted totally @ -30C.

[photoptimist]

That's a very big battery -- almost as big and heavy as the K-1 itself.

Are you saying 15000 mAh (= to 8 standard K-1 batteries) because you need the sustained power equivalent to 6000 shots or is that because normal batteries last 1/X as long in cold weather so to get decent life you need to start with ultrahigh capacity?

A battery pack for extreme cold weather photography would probably need careful thermal management with a combination of insulation and a controllable fan or vent that either uses the waste heat from the power electronics to keep the batteries warm or pulls heat excess heat from the electronics and battery. And to be commercially viable, it would also need to be multi-brand device (i.e., offered with connectors for Pentax, Canon, Nikon, Sony, standard USB, etc.).

[MJKoski]

I have 10 000mAh quality USB powerpack which loads my Galaxy S5 phone several times. I used it to run A7r2 in cold for hours in one go - I put the powerpack inside a sock with thermal hand warmers and taped it to tripod. Works.

And that powerpack is small. 15 000 mAh model was just a bit larger. The battery itself would fit into a grip easily.

[zapp]

You want a cable and connect a larger battery. Like quantum pack... no need to build a grip around it.

[jatrax]

Recent cold temperature outings with K-1 have revealed kind of low battery life.

My first reaction to reading the post title was "good grief, just buy another battery".

But after reading the post I take back that thought. In some situations, very cold weather being one, changing out batteries is awkward. An extended power grip is one solution, another would be to allow USB charging in some way. Then you could utilize the readily available cell phone external batteries. Those are dirt cheap and have 12,000 mAh plus capacities off the shelf. No need for an expensive, dedicated solution.

[photoptimist]

That USB powerpack is almost certainly designed around a 3.6 V cell system. Thus, a 15000 mAh 7.2 V battery pack would be 3X the size of that USB unit.

But the real secret to what you did wasn't the bigger capacity battery, it's the thermal hand warmers in the sock that make the difference.

Cold is great for sensors but horrible for batteries. The best design for cold weather photography would be to let the camera get cold but put the battery someplace warm.

[honey bo bo]

I have 2 new pentax grips with L190's and find them easy to exchange even with mits on. They are more than enough for what I shoot in the dead of winter. One is kept in a warm pocket. They replace 2 used I had for my K200D that were stolen along with $9000.00 other Equipment. Home Owners Replacement Value Insurance!

[beholder3]

If you need anything like that:

1. Buy a cheap powerpack which outputs 2A and 12V (not only 5V), like: https://www.amazon.com/gp/product/B00935L44E?sr=8-7&ref_=sr_1_7&keywords=100...qid=1457804315
2. Buy a regulator like mentioned here DIY Power Supply for Pentax K5 DSLR « Bob-O-Rama
3. Build/connect with cables yourself or hire the next best electrician

It's not really a challenge to convert some powerbank DC output into the 8,3V/2A DC input required, IF you really want a solution for yourself.


And photoptimist is absolutely right that keeping the battery warm is the key factor.

Thus building a battery grip with just more capacity which still hangs out there in the cold would actually be a stupid idea and no solution.

[MJKoski]

Some capacity could be used to warm up the cells inside the grip. It sounds like a bomb but such are prototypes.

Even a double capacity, such as D3x battery, extends the shooting time quite a lot. My buddy uses D4 and usually his setup lasts a whole winter day with one battery. The camera warms up a bit and the large battery is located just below the hottest part.