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Phantom Flex 4K Practical Lighting flicker

Burschi Wojnar
 

Hi CML family,
 
I am shooting a commercial with the phantom Flex 4K at 1000fps in a fashion shoot. I have shot with this camera a few time before but mainly for food shots that didn't need practical lamps in the back ground.
 
In this commercial we will be shooting sets and the director wants to have a lot of practical lamps in shot.
 
Am I right in thinking that even if I use tungsten bulbs at 1000FPS I'll still get flicker and if that is the case, how do I avoid it? Are there any tips and tricks I should know?
 
Thanks again for all the knowledge. You guys rock.
 
Kind regards,
 
Burschi Wojnar
 
Dublin, Ireland

Mitch Gross
 

Use DC power for your practicals. It’s the alternating current feeding the lights that causes the flicker. 

Mitch Gross
Cinema Product Manager 
Panasonic Systems Solutions Company of North America
New York

On Jul 31, 2018, at 6:46 AM, Burschi Wojnar <burschiwojnar@...> wrote:

Hi CML family,
 
I am shooting a commercial with the phantom Flex 4K at 1000fps in a fashion shoot. I have shot with this camera a few time before but mainly for food shots that didn't need practical lamps in the back ground.
 
In this commercial we will be shooting sets and the director wants to have a lot of practical lamps in shot.
 
Am I right in thinking that even if I use tungsten bulbs at 1000FPS I'll still get flicker and if that is the case, how do I avoid it? Are there any tips and tricks I should know?
 
Thanks again for all the knowledge. You guys rock.
 
Kind regards,
 
Burschi Wojnar
 
Dublin, Ireland

Geoff Boyle
 

I’d say that as long as you use tungsten lamps that are 2Kw or more you shouldn’t have a problem.

 

http://www.lovehighspeed.com/lighting-for-high-speed/

 

https://www.cinematography.net/edited-pages/ultrahi.htm

 

 

Cheers

 

Geoff Boyle NSC FBKS

Cinematographer

Netherlands

www.gboyle.nl

 

From: cml-lighting@... <cml-lighting@...> On Behalf Of Burschi Wojnar
Sent: 31 July 2018 12:46
To: cml-lighting@...
Subject: [cml-lighting] Phantom Flex 4K Practical Lighting flicker

 

Hi CML family,

 

I am shooting a commercial with the phantom Flex 4K at 1000fps in a fashion shoot. I have shot with this camera a few time before but mainly for food shots that didn't need practical lamps in the back ground.

 

In this commercial we will be shooting sets and the director wants to have a lot of practical lamps in shot.

 

Am I right in thinking that even if I use tungsten bulbs at 1000FPS I'll still get flicker and if that is the case, how do I avoid it? Are there any tips and tricks I should know?

 

Thanks again for all the knowledge. You guys rock.

 

Kind regards,

 

Burschi Wojnar

 

Dublin, Ireland

Mitch Gross
 

On Jul 31, 2018, at 10:08 AM, Geoff Boyle <geoff.cml@...> wrote:

I’d say that as long as you use tungsten lamps that are 2Kw or more you shouldn’t have a problem.

 

Have many 2K practicals in your home?  :-)



Mitch Gross
Cinema Product Manager 
Panasonic Systems Solutions Company of North America
New York


Stephen Price
 

As a rule of thumb, 5K Tungsten bulbs and upwards are solid for shooting high speed. These are all powered by AC current, so flicker will be seen in any tungsten bulbs under 5K when shooting frame rates over 100fps in 50hz regions.

One common way to get flicker free tungsten practicals is to DC power them. This can be done with AC/DC converters or battery banks.

Any good digital high speed camera technician should be able to advise on flicker issues and suitable lights.


Stephen Price
High Speed Camera Technician 
Love High Speed
London



On 31 Jul 2018, at 15:08, Geoff Boyle <geoff.cml@...> wrote:

I’d say that as long as you use tungsten lamps that are 2Kw or more you shouldn’t have a problem.
 
 
 
 
Cheers
 
Geoff Boyle NSC FBKS
Cinematographer
Netherlands
 
From: cml-lighting@... <cml-lighting@...> On Behalf Of Burschi Wojnar
Sent: 31 July 2018 12:46
To: cml-lighting@...
Subject: [cml-lighting] Phantom Flex 4K Practical Lighting flicker
 
Hi CML family,
 
I am shooting a commercial with the phantom Flex 4K at 1000fps in a fashion shoot. I have shot with this camera a few time before but mainly for food shots that didn't need practical lamps in the back ground.
 
In this commercial we will be shooting sets and the director wants to have a lot of practical lamps in shot.
 
Am I right in thinking that even if I use tungsten bulbs at 1000FPS I'll still get flicker and if that is the case, how do I avoid it? Are there any tips and tricks I should know?
 
Thanks again for all the knowledge. You guys rock.
 
Kind regards,
 
Burschi Wojnar
 
Dublin, Ireland

Mark Weingartner, ASC
 

You are likely to have two issues regarding practicals - one is the flicker, of course, and Mitch is right - DC power solves the problem.
The other is intensity (or rather lack of it) as once you have lit the set for your frame rate most actual practical bulbs will be pretty anemic.

So:  taking a page from the “good old days” before LEDs changed everything, I have an oddball recommendation that brings with it a caveat.

Go with very small tungsten halogen bulbs that are designed to run on 12 or 24 volts wherever the practical light has a shade… get your art department to go with lamps with shades wherever you can.
  There are still lots of them being made for automotive and transportation needs as well as a whole series of tiny T3 single ended bi-pin lamps made for projectors of various sorts - basically the lamp from inside an MR16 without the reflector.
The sockets are cheap too.
There are two common types to look at - one has a “wedge” socket and the contacts from the bulb are bent back up around the glass at the bottom of the bulb, and the other is a baby bi-pin.  Either of these is easier to work with than automotive type sockets which are bulkier.

It’s a win-win - the small globes are easy to physically wire to the inside of practical lights using mild steel wire aka bailing wire aka binding wire  and you can power them with good old fashioned car batteries either in parallel for 12v   or in series (for 24)

Better yet buy or rent a couple of deep discharge batteries used for electric fishing boats and caravans - they have handles built in.

For visible globe practicals there are high wattage versions but as they are made for mains voltage you need to run a bunch of batteries in series to get your voltage so at least try and fine 120v globes so you only need ten batteries.
Note - if you want to use a DC power supply do the arithmetic and make sure it is big enough…   300 watts out of a 12volt power supply needs  25amps.
If you do use DC power supply it need needs to be continuous - not just rectified AC power or you will still get the flicker.


I said one caveat and I meant two:

These little suckers get HOT!  
1. keep them turned off except when shooting to avoid melting/burning fixtures if they are  close to plastic

Low voltage means high voltage drop - especially for you lot that are used to 240volt mains with your puny little cables:-)

USE FAT WIRE right up to the socket.  If you can’t, use fat wire up as close as you can to the practical.  
I use 12 awg (approx 2mm) wire as much as possible even at the fixture.

You can often find two-wire “zip cord”  (lamp flex lead in English?) designed for low voltage garden lights at the DIY stores - that will be 12awg or 10awg (2mm or larger) and that would be a good wire to use for distro.

Have at it - and tell us how it turned out!

Mark






Mark Weingartner, ASC
Director of Photography
inclined towards Visual Effects



+1 818 970 6833 mobile
vfxmark@...
skype: vfxmark

Burschi Wojnar
 

Hi Guys,

Thank you very much for all your input. I'm flying out to the job now and I'm really appreciative of all the links and gems of knowledge you gave me. We are running a AC to DC converter for 500 photo floods in out lighting fixtures. be shooting this coming Sunday till Tuesday and I'll take a few screen grabs and let you guys know how I got on.

Best of luck with all of your projects and chat soon.

Kind regards,

Burschi Wojnar
Dublin, Ireland

Cinematographer
Underwater Camera Operator