Home of Professional Cinematography since 1996

Maintaining Sharpness At Highway Speeds

Published : 23rd October 2011

I bolted an FS100 to my car and went for a "quick spin" at magic hour yesterday. Tested many shutter/gain settings (Tokina 11-16mm zoom).

Here is the link http://www.vimeo.com/27696831

the footage is soft and I'm looking for a starting point to test more  shutter settings.

I don't have much experience shooting from cars except shooting *into* them on hostess trays. In planes and choppers I have not had this softness. I guess it's relative speed/distance refresh rate issue, maybe some vibration as well.

appreciate any thoughts on car mounted shooting, I figure just jack the shutter speed up to 500.

Thx,

Caleb Crosby, soc
DP
Boston
calebcrosby.com


From just reading your description:

Use a relatively inexpensive still ball head to level.

You complain of softness, while mentioning using a cheap lens adapter and a Pro-Mist as an optical flat. Are you sure your flange depth/collimation is still OK? That's critical using such a wide lens.

Mako/Makofoto,

S. Pasadena, Ca


I have an FS100 and it is quite sharp even with the stock lens. I also have a Tokina 11-16mm lens that is sharp although I haven't tried it on my FS100 yet - I'm waiting for the Birger adapter.

I have heard of many focus, vignetting, flare problems with the cheap adapters. Try your test with the stock lens or the Sony e-mount 16mm lens.

John Mastrogiacomo
Owner, Spectra Video Productions, Inc.
Las Vegas, NV
Website: spectra-video.com


Mako,

Thanks for your reply. Great idea on the still head. Just the ticket.


The lens adaptor is sharp. the lens looks good normally. the pro mist 1,has gotta go, that was a week end thing, "I'm not driving 45 min for a....."

Do you ever find certain vibration frequencies causing a pain?

(I'm not sure how well that sentence comes across ;/

Yikes,

Caleb Crosby, soc
DP
Boston


caleb crosby wrote:

>>Do you ever find certain vibration frequencies causing a pain?

Try to mount near a seam for added rigidity, but typically in pro situations we always try to triangulate.

FilmTools makes some lightweight camera mounting tools: http://www.filmtools.com/succupmoun.html

Mako/Makofoto,

S. Pasadena, CA


Mako,

You are The Source with this stuff and I am just wading in- but!

When I saw the suction cups I just went "oh no!" not Mako! and now you say you tape the edges! Oh god man!! Do you have a special prayer? Is there genuflecting involved?

I have now felt the pleasure of spinning up the power drill and popping a few into a German 123 chassis. Don't knock it till you try it

Seriously, that's a great link - appreciated. I'm poking through it.

Caleb Crosby, soc
DP
Boston


Caleb Crosby wrote:

>> the footage is soft and I'm looking for a starting point to test more shutter settings.

It looks like a vibration issue, since the problem appears to be a  function of speed.

Cameras in the slipstream -- on a car hood --can set up their own vibration frequencies in sympathy with the hood., therefore cameras mounted on a  hood need to be rigidly mounted and should definitely be supported or clamped from the top as well as the base.

One of the cheapest and most effective hood mounts is a 2x12 board ratchet strapped to the wheel wells and bumper, etc. You can then bolt whatever  to the 2x12.

All of the commercially available hood mounts (Matthews, Modern, Norm's, etc. Are simply elaborations and variations on the humble 2 x 12.

>> appreciate any thoughts on car mounted shooting, I figure just jack the shutter speed up to 500.

There is also a great deal of car/hood mount info in the CML archives.

Brian Heller
IA 600 DP


Brian Heller wrote:

>> Cameras in the slipstream ...can set up their own vibration frequencies in sympathy with the

>> hood., therefore ...need to be ... clamped from the top as well as the base.

Thanks Brian. That is great info. I never would have considered those  Forces as being so present.

Maybe I should have thought of the 2x12 tho.

I think for me the approach might be to drill out the 4 corners of the plank and then thru bolt that to the hood. I have deeper issues here and bolt fastening just seems to answer them all.

Caleb Crosby, soc
DP
Boston


caleb crosby wrote:

>> I think for me the approach might be to drill out the 4 corners of the plank and then thru bolt that to >> the hood. I have deeper issues here and bolt fastening just seems to answer them all

Caleb,

I've done the same kind of shot you're doing with an EX3, using the Cinesaddle secured in a X-pattern with a rope (4 knots) and  Cinessadle's rope clips. Worked like a charm and it is pretty safe.
Cinesaddle dampened any vibration.

Cheers

Pedro Emauz
Lighting Cameraman
Lisboa Portugal


Could be Vimeo's compression, but it seems like the footage has the same softness before the car starts moving as when travelling. Does your orig. footage look sharp before the car moves, then fall apart when travelling?

The softness looks optical to me--whether it be the adapter, flange issues or optical performance of the lens--or a combination of all 3.

Next test, maybe roll camera before even before starting the car's engine, so you have a non-vibration reference.

Jacques Haitkin DP
San Francisco


How did you set your focus - with a monitor or with the lens markings?


If the latter that could be a big problem when using a cheap adapter esp at f2.8. You should blow a few dollars and get a decent adapter with iris control - if it’s a Nikon lens.

A pro mist #1 is quite strong also.

Don't know if rolling shutter might be a problem also - it doesn't do well with vibration but I didn't notice any jello.

Leonard Levy DP
San Rafael, CA


Maybe someone already mentioned this but have you checked to see if the camera's got an OIS image stabilization working against you and creating some blending or shifting?

Just throwing it out there.

Brook Aitken
DP
Boulder CO.
www.brookaitken.com


Perhaps the duvetyn flapping in the breeze caused the excessive vibration?


Not exactly the most aerodynamic material...

Daryl Studebaker
LA DP & lurker


>> When I saw the suction cups I just went "oh no!" not Mako! and now you say you tape the edges! >> Oh god man!! Do you have a special prayer? Is there genuflecting involved

Don't knock the suction cups until you try them. The large ones with a good ball head work great on the windshield...don't use them on the car hood since the flimsy hood will vibrate. There is no need for taping but for safety you could put a ratchet strap.

The big problem is the air flow grabbing a larger camera body if it is only attached at the 1/4-20 bolt.

More surface area cradling the camera helps which is where the Cine Saddles ratcheted down help.

Definitely stay away from cameras with stabilizers built in at high speeds since the vehicle vibrations will override the stabilizer and shake the dickens out of your picture.

Good luck.

Eric Bakke
Specialty Camera Guru
L. A.


Daryl Studebaker wrote:

>> Perhaps the duvetyn

Nah, I folded a long piece until it was maybe 16 layers thick and 12" wide.

Put the folded edge into the wind and it came down 16" on either side of cam.

Cinched that with shock cord around Vinten head. It never moved.

Caleb Crosby, soc
DP
Boston