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Stuart Keasley

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Everything posted by Stuart Keasley

  1. Quick note to say, worked with Jen on a shoot in Barbados a couple of years back (Amazon - Grand Tour : Dumb Fight at the OK Coral), great to work with, definitely one of the good ones
  2. £1,300 : Seacam Canon 5D MkII Housing and Zoom Gears, including - Seacam 5D MkII housing with 2 strobe ports - Canon 16-35 Zoom Gear - Canon 100mm Macro Focus Gear - Canon 24-105mm Zoom Gear - Canon 24-105mm Focus Gear - Spares kit for the 5D Mkii housing Happy to sell items separately if needed. Photos of the kit are available here: https://www.bottlefish.net/for-sale/
  3. Bump : now listed on Ebay with a starting price of £3,000 https://www.ebay.co.uk/itm/263751562607
  4. Both in very good condition, only used a handful of times - 3000 Lumens output - 90 degree diffused flood beam - Run time : 50 mins High (3000 lumens), 100 mins Medium (1500 lumens), 200 mins low (750 lumens) Each supplied with all mount attachment, AC adapter, car charger, soft carry case. £250 per light
  5. £6,500 : SeaLux FS7 Housing Plus Accessories Includes the following SeaLux FS7 Housing (for the original FS7 camera) SeaLux DOM200 Dome Port SeaLux 5" HDMI Monitor SeaLux Underwater Housing Extended Back for FS7-XDCA Adapter 30 metre underwater SDI cable (for top side feed/directors view/raw feed) SeaLux ZR64 Extension Ring Nauticam Vacuum Detection System Peli Storm iM2975 Case with custom foam insert The housing also house a custom plate fitted to the base, allowing weights to be added for trim. Piccies can be seen here: https://drive.google.com/open?id=1yI9doXK-Cnxa1qa1cm9B3nOcFGlN5r3F For full specification of the housing, please visit the SeaLux web site: https://www.sealux.de/…/vide…/special-housings-sony/pxw-fs7/ Price includes shipping, happy to ship worldwide. Please drop me a line if you need any more info Thanks Stuart
  6. Sorry, yep, there are two versions, I didn't realise that! Good luck with it!
  7. It only supports NTSC frame rates (ie multiples of 30p), there's no info on the amount of compression or expected but rate, and there's only a handful of white balance options. I didn't get as far as reading about the automatic underwater function, but if that automatically flicks on the underwater white balance when you get underwater then it'll really ruin your day when you switch on your lights.
  8. As interceptor says, you're not comparing like for like. HD100 uses interframe compression whereas HD200 uses intraframe compression. Both are variable bit rate, so the actual end bit rate returned will depend on the subject and the type of compression applied. A low lit area with lots of dead space and no movement isn't really going to put the compression to the test. Shift your test to a well lit subject with no dead space and lots of movement, you'll see something difference. In terms of your test, your pixel peeking on a single image, so not really a conclusive or comprehensive test when comparing the quality of a moving image across different compression methods and resolutions
  9. Ah, missed the limit on the wide angle on the adapter Again, personal choice, but I wouldn't be too bothered by trying to retro fit a back filter if it means using tape etc... Too much potential for gunk near the sensor and owns workings for my liking. Another option would be to fit a filter step up ring to the outside of the lens hood, then fit a filter to that. Provided that the adapter ring ding sit proud of the lens hood, you wouldn't get any vignette etc, although you would need to ensure the step up ring fitted inside the done port aperture.
  10. Ah, missed the limit on the wide angle on the adapter Again, personal choice, but I wouldn't be too bothered by trying to retro fit a back filter if it means using tape etc... Too much potential for gunk near the sensor and owns workings for my liking. Another option would be to fit a filter step up ring to the outside of the lens hood, then fit a filter to that. Provided that the adapter ring ding sit proud of the lens hood, you wouldn't get any vignette etc, although you would need to ensure the step up ring fitted inside the done port aperture.
  11. How about this? http://dfocussystem.com/adapter-714
  12. As per my suggestion to Etc, I'd personally say record in HD. Everything you may gain from super sampling down from 4K will be more than lost by the relatively higher compression (compared to HD) that onboard on the A7s uses. If however you were pushing out uncompressed to an external recorder, 4K to HD wins by a mile
  13. As per my suggestion to Etc, I'd personally say record in HD. Everything you may gain from super sampling down from 4K will be more than lost by the relatively higher compression (compared to HD) that onboard on the A7s uses. If however you were pushing out uncompressed to an external recorder, 4K to HD wins by a mile
  14. Personally, I wouldn't be overly concerned about different colour temperature light sources, your SOLA's are at circa 6000 Kelvin, so tending towards natural light, and will probably be fairly close once you've had the light and colour fall off from a bit of distance. But more importantly, throwing light in raises over all exposure levels and so gives you something to work with. Trying to grade a noisy and low exposure image is always going to be a nightmare... Again, personally I wouldn't go above 3db of gain (on the GH4), I would try and stick to 0db as much as possible... so that puts you on ISO 800, with circa 1200 as an outside Also, unless you really need 4K, then I'd be inclined to shoot Full HD at 100Mbps instead. Whilst it's possible to supersample 4K to Full HD to improve quality, you're still reliant on decent source footage at the 4K end. Shifting to Full HD @ 100 Mbps, you're effectively reducing compression by a factor of four... the more compression you have, the more you'll see noise and issues in the low lights, so this is going to help. Just ideas and suggestions....
  15. "I do so with the purpose of being convinced rather than be convincing" For somebody who doesn't speak English as a first language, you have a wonderful way with words. I may borrow the above on occasion, if you don't mind!
  16. I'm not entirely sure what better way of proving something than with your own eyes , neither am I sure that I can explain it any better or clearer than I already have... but one last go, just for you - 360 degree shutter angle causes smearing on playback, it can be highly visible depending on the subject. - Moving towards 0 degrees shutter angle causes staccato on playback, again it can be highly visible depending on the subject. - 180 degrees sits in that middle ground, enough motion blur to blend two frames together and maintain the impression of movement without causing smearing and/or lose detail and definition in the the subject If you've taken the time to have a look at the time lapse video I linked to in my first post, then you would have seen these extremes with your own eyes.... Over to you. You have a visible example where you will clearly see the extremes, and you have multiple explanations. Trying to argue that it doesn't exist or isn't correct is quite simply a waste of time, it does, unquestionably... if you can't see it then you're not looking hard enough. Just decide whether you care, whether it would be visible in what you shoot, and if so whether it would detract from the quality of the end piece.
  17. Try taking a flood beam video lamp on a night dive, then tell me it's only good for subjects that are closer than 4 metres away ;-) For sure, it loses punch and power, and you're still going to be losing reds, but it will still bring up light levels which is what you need. Back to the other question, what ISO/Gain were you set to, and what codec and res are you recording in?
  18. As Trickster says, if you start adding in filters the you're going to have real issues when using video lights. And a filter also works by blocking out light, so you're still potentially heading towards noise issues. What did you have the ISO/gain set to, and what resolution and codec were you using? Also, what's your aversion to using lights?
  19. "Normal" means image playback on a screen will look the same to us as it would if we were sat there underwater with the scene in front of us, ie our eyes are seeing things in a way that our brain expects. It doesn't matter whether you're looking at an underwater scene, your kids playing in the park or a mountain vista with clouds scatting across the sky, your brain still processes that image in the same way. The more you deviate away from 180 degrees, the more the image will have the potential to look odd to your brain, you will add either a smeary effect or a staccato effect, depending on which way you push the shutter... which is why I tend to be stuck to 180 underwater, because I tend to be filming natural environments and behaviour, I don't want to add an effect to the look. As for trying to gain that extra bit of light by increasing the shutter, I think you need to put that into perspective. If your shooting for PAL land, you'll be running at 25p, so at 180 degree you're shutter is going to be 1/50th. By definition, the maximum you can increase that to is a 360 degree shutter, i.e 1/25th second, which is an increase of just one stop... if you're struggling for light that much, then you're already in trouble. Get some video lights, and/or shoot that scene when conditions are more favourable.... But, with all of that said, 180 degree shutter is no different from all the other rules in photography, they're there to guide you, give you the benefit of the wealth of experience that's out there, give you an idea of what you may expect if you abide by them or ignore them. But at the end of they day, it's your choice, you're the creative that's pointing the camera, play around and see what works for you, see what parameters you are personally happy to work with. That way, if you are ever faced with a low light scene that you know you're unlikely get another chance, and you need to get some more light from somewhere, you'll know whether to flick the gain on or open up the shutter.
  20. 4:2:0 compression isn't a problem, however the a7S doesn't allow 10 bit internal recording where as the GH4 does...
  21. There's really no golden rule, only suggestions/acknowledgements around the effect that different choices will bring. 180 degree shutter angle, i.e the shutter is open for half the duration of the frame, when shooting in the 24-30p range is acknowledged as providing a generally smooth and pleasing look. There will be a certain amount of motion blur that allows each frame to blend into the next. As you increase the shutter angle towards 360 degrees, you increase the amount of motion blur, depending on how fast moving the subjects are, this can becoming visible and cause a ghost like streaking. If you reduce the shutter speed to below 180 degrees you'll get an increasing amount of "shutter effect" where the image starts to look staccato on playback. Again, how apparent this is depends entirely on how fast the subjects are moving. Have a look at the following time-lapse, it will give you an idea of this in practice. The shutter speed used slowly increases from a very fast 1/800th second to a long 5 second exposure, as a result playback starts of very stop motion, gets gradually smoother and then eventually becomes streaky and blurred. What to use? Well, as above it depends entirely on the look you want to achieve, and what you're filming. It's not unusual for a director to ask me to crank up to 1/400th and faster in the sort of stuff we often find ourselves pointing a camera at.... although in general, and most certainly when underwater (and ignoring slow mo/high frame rate filming), I'll be stuck on the 180 degree rule, using other methods i.e. iris and ND filter, to control exposure. Basically it maximises the amount of light in whilst maintaining a normal look. Where's it come from? It's actually a throw back to proper filming days and the use of rotary shutters, when the shutter was a disk that spun over the top of the film as the film was pulled through. A portion of the disc would be open, this would determine how much light was allowed to hit the film. https://en.wikipedia.org/wiki/Rotary_disc_shutter The shutter angle was physically defined by the cut in the disk, a 180 degree angle would have a disc where 180 degrees of the circle, i.e half, was cut open and the remainder was left closed. Translating that to modern cameras, 180 degrees would equate to a shutter speed equal to half the frame rate, so: PAL, 25P = 1/50th second NTSC, 30P = 1/60th second Weird old land of cinema, 23.98P = 1/47.96th second Example HFR, 800 frames per second = 1/1600th second And so on.
  22. Yep, that's about the size of it... however the document you're referring to here: covers the technical standards required for delivering the footage from the edit suite as a completed product to the BBC (and others) when ready for transmission/broadcast, i.e this is what the edit suite needs to render to once they've completed all their clever grading etc. If you look at the end of Section 1.1 on page 6, the document directs you to standard EBU R118 "to assess the suitability of cameras for HD use", this is the document that the outlines the standards required for cameras (You can download a copy of EBU R118 from here : https://tech.ebu.ch/docs/r/r118.pdf) If you have a look through there, you can see that the GH4 spec complies with HD Tier SP (for specialist cameras), and would also comply with other HD tiers in terms of image quality, although it does fall down in other areas (e.g time code/genlock, audio etc). In terms of your original comment, 4-2-0 codec is acceptable, depending on the bit rate and compression method used (have a look at table 1). So anything shot on a GH4 would be considered as proper, broadcast quality HD, and would not impact on the 25% allowance for other stuff.... which is just as well, cause some of the stuff we've done on GH4s would have blown that allowance in more than a few shows already
  23. Hmm. That statement doesn't really work for me to be honest. For an application or filming segment that required a small form factor solution, e.g in car filming, drones, effect shots, GH4s could well be the principal cameras. For filming segments that required on the shoulder camera work, the principal camera would be something else. For underwater, something else again. Cameras are just tools, what we choose to pack in the box depends on what we're trying to achieve, the limitations we're faced with, chances are we'll turn up on a shoot with a reasonably wide array of different choices to get all the angles covered. Make sense?
  24. (Just as a note, the specs you posted are for the delivery of edited pieces ready for broadcast, there are completely different specs for acquisition ie how the cameras record)
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