Achieving a High Dynamic Range look?

Shooting a low shutter speed would help, as well as trying a day for night gone wrong kind of look.
 
I think what you are getting at is some form of compositing. I have never done this particular thing for this particular reason (HDR), but imagine it could be done if the camera is locked off on a tripod and the subject is static (like the landscape you linked to).

Set exposure for the shadows, recording while locked off. Set exposure for the mid tones, repeat. Set exposure for highlights and repeat.

The trick would come in the edit suite when compositing the images, taking care to mask off the blown out highlights and the detail-less shadows.

You should probably set the the HVX200 to Cine-D as it has the most latitude built in, but will blow out much easier.


J
 
the quick answer is NO you cant get an hdri from the hvx, nore the Red, nor any motion film camera out there.

Hdri is made by shooting an image with multi stops, that means shooting the image multiple times from the same angle with the same exact light, with multi stops, then combining them in a program such ad hdri shop. at this time there is no hdri video, there is an hdri camera out there, it takes about 10 to 20 minutes to do an inviroment not using the chrome sphere. it would seem to me that an hdri video camera would be possible, if you could if you could rplect the light from the lens to muiti cmos chips at different stops, some allowing little light, some allowing lots of light, but it would be very costly to figure it out, every time you split the imgae you lose light. so we'll se what the future holds

Jason Miller
 
If you're good at masking in aftereffects you could achieve the last shot by shooting the shot twice with two different f-stops and then either just cutting it in half and putting the properly exposed sky into the shot with the properly exposed city, or merge them together with some kind of blending mode. I've been trying to look for ways to shoot this style too and it's really hard. There are tons of post production techniques that are being used now, for example if you watch transformers or the new indiana jones on a very nice screen you can see that they are doing some kind of sharpening, contrast adjustments, and high-pass overlays.

I am going to do this in the next few weeks, and I'll keep you updated with what I come up with. I'm going to shoot a short thing, then export every image as an image sequence and run a batch photoshop filter preset for that simulated hdr look on all of the shots and then re-import them, we'll see how that turns out. There are tons of how-to's online to "fake" the look with photoshop and you might be able to take some of the ideas and use them in aftereffects or fcp or whatever. Just look for "How to dave hill" He's a popular band photographer who popularized the whole hdr thing.
 
Simple way: any still-camera with ability to change shutter and then do it with Photoshop and make a video out of that... best would be a real fast DSLR that makes automatic series of 3 pictures (one normal exposed, one underexposed, one overexposed) and a motor that supports the series, so that you can take about 5 fps wich makes about 3 HDR-video-frames for 5 seconds. The example you showed us is a landscape with only clouds that move, so this would work.... with people or vehicles it would look funny but not natural anymore...

with HVX: shoot same place 3 times (as suggested in other posts here) and pay ATTENTION TO THE POSITION of the camera / tripod while doing that... each mm that the camera changes position between the 3 shots will make the HDR in post more difficult... that's why Photoshop has an alignement tool if you shoot HDR photos without a tripod...

I'm sure it's woth trying with the HVX... I always wanted to try it, because I love HDR and the HVX of couse can do it as well as any other manual controlable videocamera. It's exactly the same procedure as for HDR-photos. HDR photos are done in post also - they don't come out HDR from the DSLR...
 
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You can darken bright skies with a polarizer and a grad filter, that can stretch the range three stops or even more.

Someday, someone will create a video camera that shoots at two different shutter speeds simultaneously. At 30fps, you could shoot 30 frames at 1/60th and 30 frames at 1/500th and then combine them in post. That would be a three-stop stretch and wouldn't be any higher data rate than the HVX200 does in 720p60. Hint, hint, Panasonic.
 
If you are locked off and shooting something static like a landscape, me thinks it is very possible without special HDR Software, but painstakingly time consuming and what is the return on your investment? I use graduated NDs and a polarizer like the Prof mentions with mucho successo.

Shooting dual shutter speeds simultaneously would be an incredibly interesting feature.
 
hdri suggestion

hdri suggestion

I do timelapses with a nikon d3: 9 bracketed intervals combined in Photomatix. I am thinking about this workflow with the hvx when you need e.g. a sky with details: Lock down camera. Shoot same scene with different shutter time (NOT different apertures).

Export the timelines as photo jpegs and make sure they are numbered consistently. For each frame you'll need a correct exposure and 1 over and under, or 2 over and under etc. in e.g. 1 ev steps. Make sure that the succession of images is always hte same. Batch process in Photomatix Pro and either tone map directly to photo jpegs that you import into an nle, or do this in other applications. I prefer the HS adjust operator as it gives the least flickering.

Don't have the time to do it now myself, but with certain scenes it is definitely doable. Please do it and let us know :-)

best, Soren
 
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Sounds like you could use two cams very close together, time align, and splice. Of course splicing is a post production process. You couldn't have foreground images though...

Bob
 
soren k jensen said:
I do timelapses with a nikon d3:
Click to expand...

GULP...

D3.... the dream that came true....

Can shoot with your D3 a continuous line of HDR-photos? - I mean:

- usual auto bracket series of e.g. 3 pictures (0, +1, -1)
- continuous bracketing DURING CS mode (continuous shooting)

so that you can take e.g. about 42 pictures in 5 seconds with only pressing ONCE the trigger and the D3 will do automatically 14 groups of 3 bracket pictures - ready for HDR via Photomatix....

That would be my dream because this would mean (low fps) HDR-video via DSLR.
 
Experiment this....

Experiment this....

You could try this experiment (very DIY).

Make a wheel with 2 neutral density filters (gray). One could be a transparent glass (in order to balance the wheel) and the other the ND you want.

The wheel have to be moved with a motor in a very stable way at 30 rev per second. Shoot at 60 fps, with a high shooter speed in order to reduce the risk that you blend in the same frame the border of the two filters.

If everything goes OK you should have a footage with alternating frames at two exposures.
 
can the RED's raw image be manipulated exposure-wise?

If if can then you can make HDR images from that, of course you'd have to export each frame as a TIFF or something at least 3 times with something like -2, 0 and +2 exposure settings then process them in a program like Photomatix.

It would take a looooong time but you could do it.
 
simonfilm said:
You could try this experiment (very DIY).

Make a wheel with 2 neutral density filters (gray). One could be a transparent glass (in order to balance the wheel) and the other the ND you want.

The wheel have to be moved with a motor in a very stable way at 30 rev per second. Shoot at 60 fps, with a high shooter speed in order to reduce the risk that you blend in the same frame the border of the two filters.

If everything goes OK you should have a footage with alternating frames at two exposures.
Click to expand...
This sounds like a fun DIY project! The way I see it, you'd need to be able to spin that wheel at 3600RPM (60 frames per second * 60 seconds per minute) in precise sync with the camera. The filter would be like a graduated ND filter with a hard line; half gray and half clear. If you were shooting for 24P, you'd have to shoot 48fps and spin the filter at 2880 RPM. Is that even possible?

Anyway, the results would be combined in post. It's never going to be "perfect" because you'll end up with an artifact that looks a lot like interlacing, but for fairly static scenes it could maybe work...
 
That's really genius.

"Interlacing" could be minimized by
1- not giving the images equal weight in the final output. Keep the clear as your master and only use the ND image in the areas that are blowouts.
2 - using a soft line between the clear image and the ND image, correlating a higher IRE to a higher opacity.

I think I could have an acceptable after effects plug in put together without much trouble. Now who knows how to build a wheel that precise?

In defense of the artifacting, a highlight lag of 1/30th is not much compared to the detail lag of most digital broadcasts using mpeg. I bet in most broadcast situations it would be nearly undetectable.
 
Stop down until the sky doesn't blow out, then bring up the other elements of the image individually in post. You might need to keyframe a to separate the land from the sky but you can achieve more dynamic range this way. This is one of the cool things about DVCPROHD because it will hold up better to this kind of work.


Marco
 
I tried to achieve a high dynamic range by combining two shots done at different exposures. Maybe there's a better way to combine them, (I used either Difference Matte or Key Out Brighter/ Darker in FCP) but what I discovered is that while the image had a high dynamic range, it also had increased noise.

Also, I was shooting a white wall and a window that were blown out in one shot, but in the other they became grayish and did not blend well. It seems like a difficult thing to achieve.

Do low contrast filters work?
 
It's very easy with still photography but very hard with a motion camera. Unless you really want to rotoscope the sky out 24 times a second, it's rather hard to achieve.

First off, remember that you've got 8 1/2 stops of lattitude with the HVX. That ain't bad. I'd really suggest trying to use that the best you can then limited your camera choices just to get an HDR look. Also try using gradients and polarizer to help you out.

If you really want to try the HDR look, I'd do the following: First, as others have said, lock down your camera and expose properly for your actors. If you can, try to get it so that you're against a relatively blue sky and get that as close to blowing out as possible (without quite going over). If there are clouds, and there usually are, try to make sure the actors don't pass in front of them. Then, film just the sky at your desired exposer. When you're done, go back to your first shot and key out the extremely light blue that is your sky (having made sure your actors didn't where anything that matched it) and draw out any clouds. Then composite the sky in.

A clear sky can actually be very easy to sky out if you expose properly. I just did this for a web video where the client wanted animated branches blowing in the wind over his Logo. I shot the branches against a blue sky, keyed it out, and then made a composite.

If you wanna get really creative, you could shoot on a cloud-less day, key out the sky, and then shoot the sky later, on a day with more clouds and stick that one back there. You could even get all artsy and shoot the sky at a lower frame-rate so it looks like the clouds are moving super fast.
 
What if you could build a mirror system so you could hook up 2 or 3 cameras that were right next to each other and film exactly the same thing but at different exposures?

It would be really cool if Photomatix made a fcp or avid plugin, with that program you can get really close to the HDR look with just one image. the process is called tonemapping. And it works even better if you have 3 differently exposed images.
 
The two or three camera setup would have to use synced cameras, or you'd have the same interlacing-style issue.
 
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