Tag Archives: video

Quick tips for shooting lightning – Video and Stills.

At night we shoot lightning!
At night we shoot lightning!

With the UK set to see a couple of days of strong and severe thunderstorms I thought I would put together a very quick guide to shooting lightning with both stills cameras and video cameras. Your first issue will be finding somewhere dry to shoot from, you don’t want rain on your camera or lens. You also do need to consider safety. Lightning is dangerous, it can strike many miles from a thunderstorm. If you can hear thunder you are in the strike risk area, so do take care. One of the safest places to be in a thunderstorm is inside a car. If the car is struck the electricity will pass through the body of the car and not through the occupants, before jumping from the underside of the car to the ground. If you are shooting from a car stay inside the car, don’t sit with your feet out of the door or any part of you touching the ground. Don’t sit in the car while holding on to a camera on a tripod outside the car. Don’t stand under trees, they can explode when struck by lightning, don’t stand on the very top of a hill. Use your common sense.

Arizona Lightning. FS700, 240fps and Zunow E mount 11-16mm T2.8
Long exposure captures great nigh time lightning.

For either stills or video you’re really going to want to use a tripod to get the very best results. As you often get strong winds around thunderstorms you want a good stable tripod. If it is windy keep a close eye on the camera and tripod, you don’t want it blown over by a strong gust of wind.

A wide angle lens will increase your chances of getting a lightning bolt in your shot, but the wider the shot the less detail you will see in the lightning bolt. You can always crop in to a wide shot a bit if it’s too wide. I like to have something in the foreground to give some interest to the image, but try to avoid too many obstructions to the skyline as these will block your view of the lightning.

NIGHT FOCUS:

This is probably the easiest for still photos, but it has many challenges. One is focus as it’s hard to focus on a brief flash of lightning. You will need to use manual focus, autofocus will not work. Start by focussing on a very distant object, perhaps lights on the horizon, the moon, stars or any other VERY distant object, preferably a mile or more away. Then check and double check your focus. Lightning is very fine and if it’s out of focus it will ruin the shot. If you don’t have anything to focus on set the lens to infinity, the sideways “8” symbol is infinity and there will normally be a line to mark the point of infinity focus. Infinity is often NOT at the very end of the lenses focus travel so check for the proper infinity mark. By the way, take a torch/flashlight if your going out in the dark!

STILL PHOTO’s or DSLR AT NIGHT:

You will need to use a tripod. If you have a cable release or other electronic shutter release use it to trigger the camera to prevent shaking the camera as you will need to use a long exposure. As you will be using a long exposure you want to use a low ISO. I typically use 200ISO with an exposure of between 10 and 30 seconds depending on the frequency of the lightning and how bright the surrounding area is. If you are in a town or city with lots of street light you will probably need to use a shorter exposure, maybe 10 to 15 seconds. Out in the countryside you might be able to use 20 to 30 seconds. For the aperture you don’t want super shallow depth of field as this will show up any focus errors, so don’t use your lens wide open. I normally use somewhere around f4 to f8, so f5.6 is probably a good starting point. Take some test shots and check that you are not over exposed.

As a starting point try: 200ISO, f5.6, 10 second exposures, manual focus.

Once the camera is set, it simply a case of snapping away taking pictures until you get lucky and capture one in the frame. It takes a bit of luck and patience, but don’t give up too soon, just keep snapping away. You can just delete all the no good shots later.

Evening thunderstorm in Tucson, Arizona
Evening thunderstorm in Tucson, Arizona

DAY and NIGHT VIDEO:

If your camcorder has a CMOS sensor (as most do these days) you want to use the slowest shutter speed that you can get away with. If you can control the shutter manually turn it off or reduce it to 1/25 or 1/30. This will reduce the likelihood of you getting lightning bolts that only go half way down the screen, an effect know as “rolling shutter” or “flash band”. If shooting after dark, if you have a camera with full manual control then instead of shooting at the usual 24, 25 or 30 frames per second, consider shooting at half of this, perhaps at 12, 12.5 or 15 frames per second (S&Q motion, slow shutter etc), again with the shutter set to OFF. While this does mean that the motion in your final video will be sped up it almost guarantees that you won’t get any rolling shutter issues. You will need to have the camera on a tripod if doing this to prevent excessive image blur from movement of the camera. The slightly sped up video can also give the pleasing (but fake) impression that the lightning is more frequent than it really is making your shots more dramtic. If you don’t want this simply play the video back at half speed.

STILL PHOTOS DURING THE DAY:

This is really tough unless you have special equipment. You can’t use a long exposure as you would at night because the bright daytime light will wash out the lightning bolts.

Very often a lightning bolt is made up of several flashes in rapid succession. If you do have fast enough reactions and a fast enough camera, you can get the secondary flashes. You will need to use manual focus and manual exposure so there isn’t a delay while the  camera thinks about focus and exposure which delays the release of the shutter. Use a tripod with a cable release or remote shutter and use a longish exposure, 1/30th or 1/15th as there can be up to 1/10th of a second delay between flashes and there could be multiple flashes, you don’t want too fast a shutter speed. Set your focus on a very distant object, use a low ISO, again I typically use 100 or 200 ISO. Shoot a couple of test images and set the aperture so that you have a very slightly underexposed shot, may -1EV to -1.5EV, the slightly darker overall image will help the bright lightning show up better. Then it’s just a case of pointing the camera at the storm on a tripod, with your finger on the trigger and try to hit that shutter release as soon as you see any lightning. I find it’s better to not look through the viewfinder, just look in the direction the camera is pointed. You may be lucky, maybe not, a lot will depend on the type of lightning in the storm and your reaction speed. A better way is to use a dedicated lightning trigger such as a Patchmaster: http://www.fotokonijnenberg.nl/patchmaster. This will trigger the camera electronically if it detects any lightning. It’s MUCH faster and can react much quicker than any human, but it still has some lag time so even a lightning trigger won’t capture every bolt.

A final daytime method is to use an adaptation of the night time DSLR method. If you add a strong ND filter a small aperture around f16 and use a low ISO you may be able to get an acceptable long exposure during daytime, perhaps a couple of seconds. Then set the camera to take photo’s continuously (so when you hold the shutter button down the camera will take one photo after another). By locking down a remote shutter release the camera will take a continuous stream of photos with only a very minimal gap between each picture taken. So you have a high likely hood of capturing any lightning bolts, but you will also end up with a lot of pictures that don’t have any lightning in them. You can either discard these empty frames or use all the frames to create a time-lapse video of the storm.

Have fun, stay safe.

If you find the guide useful, please consider buying me a beer or a coffee.


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Video overview of MTF Services B4 2/3″ to super35mm adapter.

In this video I take a look at the MTF Services (http://www.lensadapter.com) B4 2/3″ to super35 mm lens adapter. This adapter allows you to use a conventional 2/3″ ENG zoom lens on most video capable cameras that have a Super35 sized sensor or APS-C sized sensor. It comes in two parts, the optical converter (the expensive bit) and a simple low cost lens mount adapter ring. Adapters are available to work with the Sony PMW-F3, Sony E-Mount (FS100, FS700, EA50, NEX5 etc) as well as Canon EF (C100, C300, C500, 7D, 550D etc). To work correctly the lens must have a 2x extender. All is explained in the video.

 

NEX-FS700 Slow Motion test clip.

I was lucky enough to be able to borrow a pre production Sony NEX-FS700 for an evening and of course the one thing I had to check out was the super slow motion function. So my good friend Den Lennie let me shoot from his balcony overlooking the Belagio fountains in Las Vegas. The video speaks for itself really. The slow motion function is incredibly easy to use and I was surprise how well it performed shooting at night at 240 frames per second (1/240th shutter). There are lots of other nice features on the FS700 which I’ll write more about in a later post.

 

Convergent Design Gemini, one month on.

I’ve been testing and using a Gemini with my S-log equipped PMW-F3 for a month now and I have to say that every time I use the combo the image quality amazes me.

The Gemini firmware has been updated many times in that month, but I can report that the latest release is nice and stable and delivering the goods. The gemini is remarkable easy to use, the on screen menus are clear and concise. Talking of the screen the LCD is very good indeed. It is clearly visible even in bright direct sunlight. I’ve also been using some other external recorders with screens and the Gemini stands out as a clear winner in this regard.

Power consumption is very good. I’m using Swit 86U batteries with a D-tap to power both the F3 and the Gemini and I get around 2 hours from a fully charged battery. This keeps the size and weight of the rig very manageable, no need to upgrade my tripod or use special mounts for the Gemini, it sits very nicely on the F3’s handle. You can still use the full kit handheld without needing to use a shoulder mount or wear the recorder in a rucksack or similar.

Now.. there are some important things to consider with the Gemini. It is a high end production tool at a low end price. You do get high end, beautiful image quality and you get the same kind of files as you’d use for high end movies and commercials. These DPX files are basically sequences of uncompressed still frames. If you are considering the Gemini you do need to think about your workflow. You will be generating some damn big files, 750GB per hour and that presents a few issues.

Don’t expect to transfer your material to a laptop hard drive in real time. The Gemini uses ultra fast SSD’s because regular hard drives are not fast enough for 444 uncompressed data, so you just won’t get real time uncompressed copies to a laptop drive. It’s taken me up to 3 hours to copy an hour of footage to a fast single hard drive. If you want real time or faster transfers of uncompressed 444 (from ANY device) then your going to want a nice big, fast, raid array, that’s just a fact of uncompressed life.
One option with the Gemini is to convert your files to a compressed codec as you transfer from the SSD’s. This can actually end up faster than doing a straight copy as with a fast computer the material can be pulled of the SSD quickly, encoded and then the more compact file written to a conventional hard drive. For this to be effective I recommend at the very least a dual core i5 2.3Ghz machine. For current model MacBook and iMac users you will be able to use the Sonnet Echo Express thunderbolt to express card adapter along with a Sonnet Express34 to dual eSata adapter to get fast transfers (available December).
I’ve been transcoding to ProRes 4444 and the results are superb. Avid Media Composer 6 now includes a 444 codec but I have not tested this yet. My i7 iMac will encode from uncompressed to ProRes 444 at around realtime speeds.
Another thing you must consider is that because DPX is a stills sequence, there is no audio. At the moment the Gemini does not record audio, so I record both in camera with audio plus the DPX files on the Gemini. It’s pretty straight forward to sync them up in post. There will be a firmware update in the future to add audio recording to the Gemini, so this is just a temporary issue.

So, being realistic about things. The Gemini 444 is a great device. It’s uncompressed so the image quality is fantastic. But you must consider that this is a very high end uncompressed recorder and with any uncompressed HD recorder you will end up with big files. I won’t be using the Gemini for everything I do, the workflow doesn’t suit fast turnaround productions and frankly it’s overkill for web videos etc. But when quality is paramount the Gemini truly excels, performing as well as devices costing many times more, yet offering one of the best LCD’s, very low power and it is a featherweight in comparison to some of the other external brick recorders.

Can you see the difference between a 8 bit and 10 bit camera output?

The question is can you see a difference between a camera with a 10 bit output and one with an 8 bit output? This is being asked a lot right now, in particular in relation to the Sony FS100 and the Sony F3. The FS100 has an 8 bit output and the F3 is 10 bit.

If your looking at the raw camera output then you will find it just about impossible to see a difference with normal monitoring equipment. This is because internally the cameras process the images using more than 8 bits (probably at least 10 on the FS100, the EX3 is 12 bit) and then convert to 8 or 10 bit for output so you should have nice smooth mapping of graduations to the full 8 bit output. Then consider that most LCD monitors are not able to display even 8 bits. The vast majority of monitors have a 6 bit panel and even a rare 8 bit monitor wont display all 8 bits as it has to do a gamma correction at 8 bits and this results in less than 8 bits being displayed. 10 bit monitors are very rare and again as gamma correction is normally required there is rarely a 1:1 bit for bit mapping of the 10 bit signal, so even these don’t show the full 10 bits of the input signal.  So it becomes apparent that when you view the original material the differences will not normally be visible and often the only way to determine what the output signal actually is is with a data analyser that can decode the HDSDi stream and tell you whether the 2 extra bits actually contain useful image data or are just padding.
Where the 8 bit, 10 bit difference will become apparent is after grading and post production. I wrote a more in depth article here: Why rendering form 8 bit to 8 bit can be a bad thing to do. But basically when you start manipulating an 8 bit image you will see banding issues a lot sooner than with 10 bit due to the reduced number of luma/color shades in 8 bit. Stretch out or compress 8 bit and some of those shades get removed or shifted and when the number of steps/shades is borderline to start with if you start throwing more away you will get issues.

Updated notes for FS100 – F3 Video Review.

To see the video scroll down to the next blog entry.

The main aim of the shoot was to see how the FS100 held up against the F3. We shot on a bright sunny day by the River Thames and again in the evening in a typically lit living room. There were no big surprises. The FS100 is remarkably close to the F3. You would have no problems cutting between the two of them in a project.
I did find that the FS100 LCD appeared less sharp and not quite as good as the F3’s even though they both use the same underlying panel. This is probably down to the additional layers required for touch screen operation on the FS100. I also did not like the 18-200mm f5.6 kit lens. There was too much lag in the focus and iris controls, but the beauty of this camera is that you can use a multitude of lenses. For the evening shoot I used a Nikon 50mm f1.8 which was so much nicer to use. On reviewing the footage I did find that we were tending to over expose the FS100 by half a stop to a stop, this does make making accurate comparisons difficult and I apologise for this. I believe this was down to the slightly different images we were seeing on the LCD’s. I did use the histograms on both cameras to try to ensure even exposure, but even so there is a difference. A small part of this is also likely down to the very slightly different contrast ranges of the two cameras.
Oe thing we discovered, not mentioned in the video is that when you use a full frame lens, like the Nikon 50mm. You must ensure that the E-Mount adapter you use has an internal baffle or choke. If it doesn’t you will suffer from excessive flare. The adapter I had did not have a baffle and some shots (not used) were spoilt by flare. The adapter I have from MTF for the F3 has a baffle as do MTF’s E-Mount adapters, so these should not suffer from this issue.
The FS100 performance is so very close to that of the F3’s (at 8 bit 4:2:0, 35Mb/s) that it is hard to tell the two apart. I believe the F3’s images are just a tiny bit richer, with about half a stop more dynamic range, in most cases it takes a direct side by side comparison to show up the differences.
The range of camera settings and adjustments on the FS100 is not quite as extensive as on the F3, nor do the adjustments have such a broad range. However there is plenty of flexibility for most productions.
If you don’t need 10 bit 4:2:2 then it is hard to justify the additional cost of the F3, both cameras really are very good. Despite some other reports else where I felt the build quality to be very good and the buttons, while small, are big enough and well placed. If you do want autofocus then you will be pleased to know that it actually works pretty well on the FS100 with only minimal hunting (of course you must use an AF compatible lens).
I did also record the HDMI output to one of my NanoFlashes at 100Mb/s. Comparing these side by side it is extremely hard to see any difference. It is only when you start to heavily grade the material that the advantage of the higher bit rate Nanoflash material becomes apparent. There is less mosquito noise in the NanoFlash material. I was really impressed by the AVCHD material. The lack of noise in the images really helps.
The FS100 really is the F3’s little brother. The pictures are remarkably close, which they should be as they share the same sensor. The FS100 packs down into a remarkably small size for transport. The loan camera from Sony was actually packed in a case designed for the MC1P mini-cam, about 15″x10″x5″ so very compact indeed. The F3 is considerably larger and bulkier, in part due to the extra space taken up by the built in ND filters.
The lack of ND filters does need to be considered. There are some clever solutions in the pipelines from various manufacturers as well as existing solutions such as vari ND’s, screw on ND’s and a Matte Box with ND’s, so it’s not a deal breaker
I think there is every chance that the FS100 will be the first NXCAM camera that I will purchase. It will be a good companion to my F3. It’s modular design will allow me to get shots that are not possible with the F3. I felt that the FS100 (with the 18-200mm lens that I don’t like) was better suited to “run and gun” than my F3 with either manual DSLR lenses or PL glass. You can, with the FS100 simply point the camera at your subject and hit the one push auto focus and auto iris and have an in-focus, correctly exposed shot. This is much more like a traditional small sensor camcorder in this respect. The long zoom range also makes this more like a conventional camcorder, although there is no servo for the zoom.

In conclusion, in my opinion, for “run and gun” or quick and dirty setups the FS100 with the 18-200mm lens has an edge over the F3 due to the fast auto focus and auto iris one-push controls. For more precise work and shallow DoF your going to want a different lens, something with manual control and calibrated focus and iris scales. For more demanding shoots then the F3 is probably the better choice with it’s slightly improved dynamic range and the ability to use S-Log and 4:4:4. In either case these cameras can produce highly cinematic pictures and I see no reason why you could not shoot a great looking feature with either.

Sunrise Over The Hudson

Well, I’m now in New York preparing to introduce some of our potential dealers to the Genus Hurricane Rig. I’m going to be spending some time with the guys at ZGC and Abel Cine showing them how the 3D rig works and what it can do before heading down to LA for ShowBiz Expo later in the week. Our hotel overlooks the Hudson river and Manhattan so I could not resist the opportunity to shoot the sunrise this morning. Apart from anything else I’m jet lagged so was up at 4am!! The video was shot with my trusty EX3 at 1 frame every second, sped up to x400 in FCP. I used the TLCS controls to limit the maximum gain to +6db and to introduce shuttering when the iris gets to f11. This helps deal with the huge changes in light levels. Now I know where the sun appears I might re do this later in the week, centered on the sun. Hope you like it.

Vapour: The Sky in motion.

The last couple of days provided some really spectacular skies with amazing vapor trails and fluffy clouds. So I grabbed a selection of cameras and shot a bunch of timelapse which you can see cobbled together in this clip. I used a Sony PMW-350 and a Canon 350D and 550D. Amazing how well they match after a quick grade. I also included an previously un-used Aurora shot from Iceland at the end. The name of the clip comes from the fact that clouds are made of water vapor and ice crystals.

You can also watch it in HD on Exposure Room.

How I shoot the Northern Lights

Well I have just returned from Iceland where I held a couple of 3D stereoscopic master classes and a workshop on video for the internet. They went well and we all had fun despite almost a foot of snow fall the morning of the classes. On the last day of my trip I decided to try and get some more Northern Lights footage. As I am often asked how I do this I put together the clip below which explains what settings I use for the Aurora and also gives a brief description of S&Q on an XDCAM EX. Basically what I do is use the EX Slow Shutter at 32 or 64 frames to increase the sensitivity of the camera. For a dim Northern Lights display I use 64 frames but for a bright display I drop down to 32 frames. The slow shutter acts like a long exposure on a stills camera. I then combine this with interval record shooting at 1 frame every second. I did also have a Canon DSLR with me and tried to shoot the Aurora with that. I found I needed a 10 second exposure at 800 asa to get a similar result to that achieved with the EX. The 10 second exposure means that it would take longer to get a decent length video sequence and most of the motion of the Aurora would be lost. Some of the exposure difference was I admit to the slower F4 lens on the Canon compared to the Sony EX’s F1.8, so perhaps with a faster lens you could bring the exposure down to around 5 seconds and this is something I hope to try when I go Aurora chasing next winter.

If you watch the video make sure you stay to the end to check out my attempt to record a piece to camera in 60 mph blowing snow! Don’t know why I even thought it would work. What I will say is that my new Vinten 5AS did a great job of keeping the camera steady in some pretty extreme conditions.