Any advice on taking a difficult shot?

Niels Neeskens

Niels Neeskens

Well-known member
Hey everyone,

I am looking for any useful advice regarding a difficult shot we are going to take for a client. We are going for a 'Jaws effect' shot, where we are focussing on an object and do a dolly shot towards the object while zoom out. This way you get the effect of the object that stays at the same spot, but the surrounding are changing in a dramatic way. Next to that it should be a timelapse shot, where people come in and out the room and touch the object. We want to take the shot for a minimum of 1 hour. We'll have to take this shot within 2 weeks, so time pressure.

A few problems with this shot:
- We want to shoot this shot with our floatcam dollycrane. This way we can control the movement forward by the motion control remote. By moving forward you can use quite a small part of the dolly, without seeing the front site of the rail in the shot. We probably solved this problem. We builded a piece that can be attached to the head of the dolly and goes up for a meter high. This way we can go further back without seeing the front of the rails in the shot.
- What is the best way to achieve the light beam effect in the timelapse with people come in and out of the room with the Sony FS700? S&Q 1fps and 1/30 shutter? Will this achieve enough motion blur? It will be a good lit room, so probably we'll have to use a couple of ND filters.
- We have to focus on the object, but we are doing a long time-lapse. A manual focus pull would be very difficult. We've found a focus assist that has a laser that points on the object and keeps the focus. I don't have the name here, but will have it tomorrow. Problem is, that it will be available in the end of the year and we'll have to take this shot within 2 weeks. Does anybody have some advice on the best way to do this?
- For a test shoot we used a Canon 16-35 mm lens. I thought the effect of the changing surroundings was to little. We have to make this more dramatic. Probably this lens is to wide for this. We haven't had to time to test it, but maybe the Canon 24-70 mm will get a more dramatic effect. Any tips for this problem will help a lot.

I would be very happy with any input for this shoot. Hope to hear from you guys. Thanks in advance.

Niels
 
Niels Neeskens said:
Hey everyone,

I am looking for any useful advice regarding a difficult shot we are going to take for a client. We are going for a 'Jaws effect' shot, where we are focussing on an object and do a dolly shot towards the object while zoom out. This way you get the effect of the object that stays at the same spot, but the surrounding are changing in a dramatic way. Next to that it should be a timelapse shot, where people come in and out the room and touch the object. We want to take the shot for a minimum of 1 hour. We'll have to take this shot within 2 weeks, so time pressure.

A few problems with this shot:
- We want to shoot this shot with our floatcam dollycrane. This way we can control the movement forward by the motion control remote. By moving forward you can use quite a small part of the dolly, without seeing the front site of the rail in the shot. We probably solved this problem. We builded a piece that can be attached to the head of the dolly and goes up for a meter high. This way we can go further back without seeing the front of the rails in the shot.
- What is the best way to achieve the light beam effect in the timelapse with people come in and out of the room with the Sony FS700? S&Q 1fps and 1/30 shutter? Will this achieve enough motion blur? It will be a good lit room, so probably we'll have to use a couple of ND filters.
- We have to focus on the object, but we are doing a long time-lapse. A manual focus pull would be very difficult. We've found a focus assist that has a laser that points on the object and keeps the focus. I don't have the name here, but will have it tomorrow. Problem is, that it will be available in the end of the year and we'll have to take this shot within 2 weeks. Does anybody have some advice on the best way to do this?
- For a test shoot we used a Canon 16-35 mm lens. I thought the effect of the changing surroundings was to little. We have to make this more dramatic. Probably this lens is to wide for this. We haven't had to time to test it, but maybe the Canon 24-70 mm will get a more dramatic effect. Any tips for this problem will help a lot.

I would be very happy with any input for this shoot. Hope to hear from you guys. Thanks in advance.

Niels
Click to expand...

My first thought would be why are you using the FS700? Rent a DSLR with intervalometer and shoot 1fps stills if it is a timelapse, that will give you access to great autofocus for each frame (set the focus point carefully, should work if the subject stays in the same spot through the move) An FS700 at 1fps will only give you a 2MP image, whereas an inexpensive DSLR will give you each frame >17MP proabably which gives you extra room to stabilize both the move and the zoom effect or perhaps even execute the zoom change partly or even entirely in post (though DOF will be affected significantly if you crop a lot).

I'm not sure what you mean by a light beam effect, do you mean the look of light trails as moving objects blur through the frame? If so, 1/30th will not give you that effect. I prefer to use longer shutters when doing timelapse unless you want the jittery look of sharp objects appearing in frame and then disappearing. Longer shutter will reveal the movement of people in the frame and allow you to see their movement through the frame but make it less likely you'll recognize who they are or see their finer actions. Timelapse with a fast shutter sort of looks like stop motion with no blur and I find can make your frame very busy with sharp moving objects that appear only for one frame or two, but timelapse with a longer shutter (like 180deg aka half the frame time) looks more like motion is actually happening naturally but at much faster speeds, which will really help draw attention to the subject in the frame that is not moving as much since it will be the only part of the frame not very motion blurred.

Focal length range depends a lot on what you want out of the move. Probably a longer zoom range will be better and give you more options. A wide zoom lens will help a lot if you want to get a lot out of a limited-length motion control track, but will likely end up showing your track in the frame. It really depends a lot on the subject matter and intended framing, though.

How long is the final length of the shot supposed to be?
 
What Noah said.

What he didn't mention was control of the zoom: As well as controlling the creep forward of the dolly, you'll need a motion control motor to adjust the lens zoom position as you move forward. Depending upon the length of the final video, you might be able to set each position by hand - i.e. if your 1 hour of realtime only needs to produce a 4sec of footage, you'll have roughly 30 sec between each shot to adjust the zoom. But even then you'll have to be very careful as you'll need to divide the zoom change into 100 separate positions (4sec*25frames/sec=100 frames). But if the shot needs to be longer, you'll have less time to be more accurate - and that probably means it needs to be computer controlled.

You'll also need to decide is whether or not to shoot Raw stills or Jpegs. Personally I'd do both - as you'll be able to do a quick movie from the jpegs: just set the still image time in FCP to 1frame, drag all the jpegs in to a bin, then drop the bin into a timeline. But you'll have the extra grade-ability of the Raw files, although you'll need to use After-effects to build the video.
 
Controlling the zoom is a significant question. It could be done with a motion control lens motor, though that might be a bit hard to get your hands on. There aren't many other servo zoom lenses that will creep at the speed you need. The other option might be manually adjusting the zoom position periodically and stabilizing the zoom move in post.
 
I think the timelapse zoom is a specialised thing to do. I theory the zooming needs to occur while the shutter is open - but you can probably live without that! You need a programmable focus motor of the highest quality - maybe approach Heden or Preston. Maybe stop-mo specialists (arrdman?) could suggest a motor

NOW STOP - forget a physical zoom !

Here is a thing.. a zoom in is (in terms of optical appearance) the same as a crop of the file. - shoot, raw on a D800 (or a Phase one Digiback) and crop in post - loads space for digitally zooming and still having enough IQ to deliver an HD file. ALso very simple to keyframe in post.

S
 
Problem with a post-only zoom, is that there is still a limit to how much you can crop, even a 5Dmk3 gives you images with 5760pix wide, and I probably wouldn't recommend cropping all the way down to 1080p, but if you did youd get up to a 3x zoom range and it depends on your needs, since if you are delivering in SD or 720 for the web or something, cropping that much might be fine. The other issue is that you are changing your sensor size by cropping so it will not look the same as actually zooming, but it might be an interesting effect and it will give you a lot of room in post to create the perfect zoom. You will have a lot more depth of field at the "telephoto" end, which might be fine or might not be noticeable if you have lots of depth of field in general, plus the increased depth of field may be balanced out by the greater enlargement of the background due to the narrower FOV at fake-telephoto.

The post-only method is probably the easiest to shoot, which also means it would be easy for you to test out and see what you can get away with. I'd definitely recommend testing it out.
 
Phase or the D800 are not a 5d3, rental on either would I guess be cheaper than a cinezoom and prog motor.

interesting to consider the effect of a change in sensor size!
 
Sounds like you want to do this all in camera, in which case the suggestions here seem ideal. However if it was me, i'd be shooting elements for comp in post and maintain total control over the move, focus and the degree of 'vertigo' effect you're looking for. I don't know whether that's an option for you at all?

As pointed out 1/30th is not going to get you very motion blurred people coming in and out of frame. You could post motion blur them, then you could have them blurred as the come in but sharper when they touch the item.

Difficult to know without seeing boards and layouts...

cheers
Paul
 
Noah is right, doing a counter zoom in post won't give the perspective change you're after - it will just change the depth of field - as image magnification is increased. If you start off with a wide DOF and a big object this might be noticeable, but I suspect it will be very slight - especially as you won't see any of the foreground changes as the people will be blurred by motion blur anyway.

To do the counter zoom you're going to need the lens motor. I googled 'stop motion DSLR lens motor' earlier and a coupe of products seemed to pop up.
 
nyvz said:
My first thought would be why are you using the FS700? Rent a DSLR with intervalometer and shoot 1fps stills if it is a timelapse, that will give you access to great autofocus for each frame (set the focus point carefully, should work if the subject stays in the same spot through the move) An FS700 at 1fps will only give you a 2MP image, whereas an inexpensive DSLR will give you each frame >17MP proabably which gives you extra room to stabilize both the move and the zoom effect or perhaps even execute the zoom change partly or even entirely in post (though DOF will be affected significantly if you crop a lot).

I'm not sure what you mean by a light beam effect, do you mean the look of light trails as moving objects blur through the frame? If so, 1/30th will not give you that effect. I prefer to use longer shutters when doing timelapse unless you want the jittery look of sharp objects appearing in frame and then disappearing. Longer shutter will reveal the movement of people in the frame and allow you to see their movement through the frame but make it less likely you'll recognize who they are or see their finer actions. Timelapse with a fast shutter sort of looks like stop motion with no blur and I find can make your frame very busy with sharp moving objects that appear only for one frame or two, but timelapse with a longer shutter (like 180deg aka half the frame time) looks more like motion is actually happening naturally but at much faster speeds, which will really help draw attention to the subject in the frame that is not moving as much since it will be the only part of the frame not very motion blurred.

Focal length range depends a lot on what you want out of the move. Probably a longer zoom range will be better and give you more options. A wide zoom lens will help a lot if you want to get a lot out of a limited-length motion control track, but will likely end up showing your track in the frame. It really depends a lot on the subject matter and intended framing, though.

How long is the final length of the shot supposed to be?
Click to expand...

Thanks a lot for the advice Noah! We have a DSLR so that would be an option. For the timelapse it would probably be a better option and with the focus point the focus would be much easier. The zoom in post is not an option, because we want to get the 'Vertigo' effect (I called it the Jaws effect earlier, but off course Vertigo was before that).

Indeed I mean the light trails as moving objects blur. Longer shutters would be the way way to go for this.

Not sure what the length of the shot will be yet.
 
Hey guys,

A quick follow up.

Later this year there will be motion controlled machines that will be perfect for a shot like this, but we need it now, so that's not an option. We haven't had the time to test a lot, but have monday and tuesday next week to do so. Thursday is the shoot.

So this is probably the way we go for this shot. We build a meter high piece on our floatcam dollycrane head, that we attached the fluid head of the tripod on. This way we don't see the track by moving forward. So that problem is solved.

Next to that we control the movement by the motion control of the floatcam dollycrane and set it to take a shot of 20 minutes (not really sure yet about the length of the shot, it depends on how slow we can set the automatic zoom of the lens, so it's open for discussion). In the end we do a ramp (option on the motion control of the floatcam), so the movement will slow down with a ease out.

We are probably going to buy the Sony NEX PZ 18-200mm F3.5-6.3 OSS for the Sony FS700 (http://www.fotokonijnenberg.nl/product/1723131/sony-nex-pz-18-200mm-f35-63-oss.html). We are going to check the lens on monday, and I hope we can get the automatic zoom out as slow as possible. We will have to set the automatic zoom out as long as we are doing the shot and measure it to match the movement forward. This is still a problem, because I can't seem to find a spec of the lens about how slow you can set the automatic zoom out. Anyone who know this?

Next to that we will use a aperture as high as we can get, to get as much sharpness as possible. We need a lot of light for that. This way we can control the focus on the point of interest as good as it gets. The object probably will be placed in the room in post, so that should make it easier. We will try to fake the depth of field in post as good as possible.

Conclusion. Still the most difficult part, but the most important part too, is to fit the movement forward to the zoom out. The ease out makes this even more difficult. So as I write this down, I figure that if we do the ease out, we have to do the zoom out manually. If we motion control the floatcam dollycrane in one smooth speed, we can set the zoom out automatic. Then the speed of the motion control of the floatcam dollycrane has to match to slowest speed of the zoom out of the Sony NEX PZ 18-200mm F3.5-6.3 OSS lens. This speed still has to be good enough to get the timelapse of people walking in and out of the room.

Any remarks, tips of tricks on above are welcome.
 
I very much doubt you can zoom slowly - maybe 5 seconds max if it is like the EX1?

The AF should handle focus, at F22 or suchlike you will get diffraction and a soft image.

There is really no reason not to use a stills camera for a timelapse which at 5kraw will give you a huge range of options in post

Also if you use AF it will work!

S
 
As Sam said, basically. I don't know of a single zoom control (aside from timelapse zoom controls) that will operate slower than a few seconds from wide to tele.

However it did just strike me that the other option is to forget timelapse and just do it using stop motion (again. With a DSLR). Set up your frame, using a the video mode of the camera - and an external monitor. Mark the edge of frame on the monitor with a china graph pencil then space your move on the dolly based upon the number of frames you need the final video to be. Then take a shot, move the dolly along to the next position, reframe the shot based upon the marks on the monitor, take a shot, move on etc.

Obviously the people you're working with will need to be quite patient as they'll need to move, hold, move, hold etc and it will take a hell of a lot longer than using a zoom motor, but it should work. The though bit will be coordinating their move with the shutter.

Alternatively, you could do the move as a stop motion. Then shoot the people against greenscreen, using the motor controlled dolly move (having an operator just rough in the zoom on the lens), then comp the two (three with the object) moves together in post, I'm sort of assuming the blur of the people will hide the roughness of the zoom (or you can adjust that move in post).

Or you shoot the whole thing timelapse and use the marked-monitor method to get an operator to rough the zoom in and fix it in post.

good luck though!

Colin Elves
Director of Photography,
London, UK
www.colinelves.com
 
We've had folks do similar shots with our camBLOCK Motion Control system.

The Dolly track/skeleton can be on the floor with the system in "sled mode", with a tripod on top of the dolly and the Pan/Tilt head (if needed) on that. Then two lens controllers are used to drive Focus and Zoom.

Keyframes can be setup so perfect Vertigo shots are easy to produce.

We rent/sell the systems at http://www.camblock.com
 
You must log in or register to reply here.
Back
Top