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CheungyDiver

Member Since 26 Nov 2002
Offline Last Active May 18 2015 09:23 PM
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Posts I've Made

In Topic: Giant Octopus in East Sea of Korea

29 April 2015 - 11:19 PM

Thats a big O'puss Eunjae!

 

They grow them big in the Korean sea.....One has a white patch on its "head". Why is that? Warning sign or something?


In Topic: Lets talk lumens!

29 April 2015 - 11:13 PM

Yes. You will need less angle of beam in certain situations. Beam should be even in either spot, medium beam or wide beam. To do so correctly in a powerful light would need some sort of lens/ diffuser. 

 

One thing to note is that better powerful light heads do not use array of power LEDs that is spread out in the light because that would produce multiple shadows. 

 

Two cents worth...  :)


In Topic: Lets talk lumens!

28 April 2015 - 05:15 PM

CRI (colour rendering Index), lots of power yes but must be  dimmable and non- flickering or colour shifting. Sensible battery system for travel and weight. Variable beam adjustment. 

 

Just my two cents


In Topic: New Lights

09 April 2015 - 02:34 PM

hi Moses

 

 

It depends on the situation. more powerful light gives you more options of what video you want to shoot. These lights still need variable output though. Now thats difficult to make consistent. Say in still water and it is gin clear I would use as much lumen as possible with wider beam. Some UW wrecks are difficult to lit properly for a wide scene. In some waters I would use a narrow beam. With flood lights a condenser lens will work and produces a nice long throw beam. Even with these less powerful light you could do a lot with cameras with high ISO and DR. Well a year ago lights with 2000 lumen is nothing to sneeze at. I say that because now there are portable LED lights that could pump out more than 22000 lumen. But cost over 2K. It is only a matter of time when 4000 to 6000 lumen become the norm and price will drop. It all boils down to demand. Not many would spend a princely sum on a light. More power means more heat generated, bigger power demand, heftier electronic ballast especially for dimming. Color too. High CRI (color Rendering Index) and high power is quite complicated to do. Again difficult for dimming and maintain same quality of light without any flicker. I have seen some high power ones but these are not yet up to par with Keldan or the like. I am sure the Chinese companies is more than capable. R&D and prototyping is costly. Powerful battery is also the limiting factor. Battery tech. with enough juice and light weight for powerful lights is really limited to Li-ion and Li-po.  Li-Ion I see at present is the only option as it is in pressurized containers. Li-Po is out of the question for powerful UW lights. Too dangerous.

 

One way to get more light is to get a few of these and bundle them together. I tried four lights in two, two configuration. Output per light is 2500 lumen. Total 10000. Total cost is still less than the cost of a single 6K or 8K light made by premium brands. Not as convenient but does the job like you say :)

 

Cheers

 

David


In Topic: Canon Cinema EOS XC10 4K Camera

08 April 2015 - 08:06 PM

I think Canon is in a dillema. They also launched a C300 MII which is only just heads above water in terms of up to date 4K specs. not when Sony has a Fs7 costing half the price of the Canon. The C300 is still the best selling broadcast & news camcorder Canon produced. They have yet to annouce the 5DMIII replacement. Rumor has it that is 4K enabled. I will not be surprised if the wizards at Magic Lantern get there with the Linux hack  before Canon's announcement.

 

This neither small or large camera seems to come from some 90s throwback bridge camera design. Had they just allow interchangeable lens mount say the EOS M this would make it more attractive..ie. allowing Meta bone speed booster adapter like the one for the Black Magic Pocket rocket wotsit camera.

 

One saving grace is that it could allow recording to external 4 recorder like the shogun at 10 bit 422.

 

As for if this thing could be used in drones.  Too big for stablising gimbal and no remote zoom control. A zoom like that with no wide angle...seriously not even close to competing with Go Pro H4 or the higher end GH4 and gimbal.

 

I think this latest release just show how unimaginative canon has become. Panasonic, Sony and even Samsung have cameras that could run rings around this camera. These are just my opinion of course and if there is redeeming features I have missed then let me know. I hope the image from the tiny one inch sensor is halfway decent when they actually available. The demo reel is bad. Cliiped footage  in the yellow colour highlights,

 

cheers

 

David