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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Wait a second guys..... Power supply solution.

This way outside my area. But I have used similar kit for powering a Lappy out in the field. From my understanding you need to run this system thru a safety cut off box of some sort as the power can vary & possibly fry internals. But it did work for me & my DIT services in the field.

Hopefully others can give a more affirmative yeh or nay!
 
Tethering the camera like that would really limit your options. Takes up space on a dolly, can't use a jib / crane, and now steadicam is out of the question. Not really worth it in my mind. Also, eight hours won't last through a standard shoot day, assuming it makes it that far.
 
Mike Garrick said:
This way outside my area. But I have used similar kit for powering a Lappy out in the field. From my understanding you need to run this system thru a safety cut off box of some sort as the power can vary & possibly fry internals. But it did work for me & my DIT services in the field.

Hopefully others can give a more affirmative yeh or nay!
Click to expand...

Using this for a DIT station seems like a much more reasonable idea. It would be great for the shoot I'm on now, where I'm just wired to a generator out in the middle of nowhere.
 
If you have the right cable you can skip the inverter and grab the 12volts off the battery. This would get you more run time too.
 
Michael Pyon said:
Why don't people just buy a portable power generator and power the camera through an ac power cable? It seems like a much cheaper option....

http://www.powerportstore.com/powerport.htm#PowerPort 259
Click to expand...
If you're considering going down this road you may as well save yourself some cash and use a personal ups (http://www.amazon.com/Cyberpower-CP...2?s=aps&ie=UTF8&qid=1328240020&sr=1-2-catcorr)
For $160 you get 900w of power with a rudimentary LCD.


Additionally Costco sells these ups from $100 to $120 with a coupon.
 
Damn, that's a great product there Sid.... 900w of power should mean about 15hours. That's much better than 2 redvolts, don't ya think?
 
Just my personal thoughts but if you want 12v dc to run a camera why not just use a 12v sealed led acid battery ( SLA gel cell ) in your pocket. Thats all the UPS has inside it... SLA are very cheap, huge range of capacities and easy to charge. Also no problems flying them around the world unlike Lithium packs.
We use then for running our cave filming lights all the time. Maybe not as much capacity per density as Lithium but on cost andy safety its a no brainer.

www.gavinnewman.com
 
Michael Pyon said:
Damn, that's a great product there Sid.... 900w of power should mean about 15hours. That's much better than 2 redvolts, don't ya think?
Click to expand...

Well keep in mind that 900w ups is going to weigh 20 to 25 lbs.
 
Michael Pyon said:
Damn, that's a great product there Sid.... 900w of power should mean about 15hours. That's much better than 2 redvolts, don't ya think?
Click to expand...

It's been a while since I took electronics but I think that math would need to be adjusted. Based on newegg the runtime at 150 watts is around 50 minutes. That would give it an approximate energy capacity of 150*50/60=125wh, which at Scarlet-X's 60w draw would run for approximately 125wh/60w=~2hours. Based on the spec it looks like it might be more efficient at lower wattages so it might be a little more.

(15 would be the number of Scarlet-X's that you can run simultaneously to drain the battery at full load, which I'd assume would deplete it in a minute or two)
 
What is a "Lappy?" Is it a type of light?


Mike Garrick said:
This way outside my area. But I have used similar kit for powering a Lappy out in the field. From my understanding you need to run this system thru a safety cut off box of some sort as the power can vary & possibly fry internals. But it did work for me & my DIT services in the field.

Hopefully others can give a more affirmative yeh or nay!
Click to expand...
 
For cart power you could consult jwsound.net and the sound guys (who are also known here, despite being responsible for 50% of every film/tv shoot, as "extra baggage") who run their carts.
 
Pardon the shameless plug here, but in addition to our production company, we have a small manufacturing company that makes Jibs, Sliders and in reference to this thread Portable Battery Supplies that we are hopeful will be able to provide Power to our Scarlet when it arrives next week. We package a high quality Medical Grade Sealed Lead (SLA) battery (either 18AH or 35AH) in a Pelican Case that we have used for a number of applications including: cameras, Monitors, Hot Head on a jib, teleprompters, LED lights and Gyro Stabilizer mounts. The case has 4pin XLR connectors along with a Cig Lighter port to run a variety of devices. We often run an AC inverter for laptops and other small 110V devices as well.

Both batteries have a continuous out capacity in excess of the 60watts that are needed to power the Scarlet, but we just want to do a little testing to confirm. Being lead batteries, they are not light (13 & 25lbs respectively), but on a jib, dolly or sticks in a more static situation are extremely handy in many applications.

FYI, battery consumption is not a linear thing, but rather a geometric curve. The amp hour rating is based on one amp of draw, so if a device draws 5 Amps (like the Scarlet), a 15 AH battery would not power the device for three hours. More like a little over two hours would be realistic. And beware of lead acid batteries much below 15AH as the 60W draw from A Scarlet could easily and quickly drop the voltage below the 11.5V cutoff for the device, well ahead of the battery actually being exhausted.

We will gladly offer a discount to RED users if anyone is interested after we complete testing on our end. They can be seen at www.t-jib.com
 

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this might be oddball, but the sony ex1 batteries are 14.4v, and the ex1 has a power draw of about 15 watts, so the bpu60 4 hour battery should power the scarlet for about an hour, for 250 bucks a pop, and the dolgin adapter is 50 bucks
 
Hey Gavin,
Small SLA batteries (one that might fit into your pocket) run the risk of dropping below the 11.5Volt threshold of minimum allowable power consumption of the Scarlet. Unlike Lithium batteries that start at 14.4 volts, SLA start just above 12Volts and under the heavy draw of the 60watt Scarlet quickly might drop below 11.5 output in spite of actually having a fair amount of charge remaining. It takes about 10AH to supply 60watts for any reasonable duration.
Gavin Newman said:
Just my personal thoughts but if you want 12v dc to run a camera why not just use a 12v sealed led acid battery ( SLA gel cell ) in your pocket. Thats all the UPS has inside it... SLA are very cheap, huge range of capacities and easy to charge. Also no problems flying them around the world unlike Lithium packs.
We use then for running our cave filming lights all the time. Maybe not as much capacity per density as Lithium but on cost andy safety its a no brainer.

www.gavinnewman.com
Click to expand...
 
William, you are definitely on track. Though the camera operates at 60 watts, that is at 12 to 14 or so volts. To run on AC, the AC adapter has to convert 110V to 14V to run the Scarlet. I looked in the Operations Manual, but could not find the draw of the AC adapter when powering the camera. So actually, it probably would not run the camera anywhere near even two hours. The spec sheet mentions a 8.5 AH SLA battery and even without the loss in up converting to 110V, the battery would only run the Scarlet a little over one hour. A UPS is not a very efficient way to go, you are taking a 12V battery, up-converting it to 110V to power an AC adapter that is in turn going to down convert it back to 14V.

William Seale said:
It's been a while since I took electronics but I think that math would need to be adjusted. Based on newegg the runtime at 150 watts is around 50 minutes. That would give it an approximate energy capacity of 150*50/60=125wh, which at Scarlet-X's 60w draw would run for approximately 125wh/60w=~2hours. Based on the spec it looks like it might be more efficient at lower wattages so it might be a little more.

(15 would be the number of Scarlet-X's that you can run simultaneously to drain the battery at full load, which I'd assume would deplete it in a minute or two)
Click to expand...
 
Hey Darren, The BPU60 is actually 56WH which means that you are definitely close in your calculation. There is a geometric curve in effect with the high consumption draw of the Scarlet. It is better for Lithium than with lead acid, but definitely still applies. A battery that lasts 4 hours on a 15W draw, will not last 1 full hour on a 60W draw. You would probably lose about 25% duration due to the geometric curve on higher consumption devices. Realistically, it would probably last about 45 minutes or so. You would definitely want to factor that into your cost per hour calculations.
Darren Levine said:
this might be oddball, but the sony ex1 batteries are 14.4v, and the ex1 has a power draw of about 15 watts, so the bpu60 4 hour battery should power the scarlet for about an hour, for 250 bucks a pop, and the dolgin adapter is 50 bucks
Click to expand...
 
Hi Carelton,
Wow, thanks for your info about your new upcoming large battery. I really like it and the price.
http://www.t-jib.com/products4.asp

For me, I like the idea of a light weight scarlet, so not keen on attaching a battery to the camera, for inside work at least.
So I bought an AC adapter and can run all day and night no problem, well, no power problem anyway.
But I do like your battery idea, as this fits in when I have no AC around the place.

Also, I wish I had known about your jib's, as I just spent $6,000 on some one else's, so I for one think it is great that anyone can make a plug for their products here in this open space. Afterall, if anyone has problems with your products, it will be in the open and you can answer their concerns. I think this is wonderful.

cheers
James
 
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