FOURNIER CLOSE-UP By Bob Hart On ExposureRoom

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This clip is of Bob Grimstead practicing his display for the 2008 Red Bull Air Race on the Swan River in Perth Western Australia.

Be warned, it is quite a long clip of the entire sequence so is a big download

I put a 1084mm f10.5 MTO mirror telephoto on a Letus Extreme 35mm adaptor attached to a Sony PMW-EX1 camera. Way overkill and well inside the f5.6 boundary for artifacts. You will observe at the end of the clip that I finally managed to break the Sony grip on CMOS rolling shutter artifacts.

A typical CMOS rolling shutter artifact occurs but only becomes apparent when almost the entire frame is covered by the propellor disk.

Sony definitely seem to have some trick going. When there is a smaller area of rapid movement within the frame there do not seem to be any artifacts.

The camera seems to be also happier when shutter is selected off. You may also observe some horizontal frame shears on rapid movements during the follows. Sometimes these appear to be generated by the encoder during export to the windows media file.

With the 1084mm lens, the image becomes a five degrees field-of-view. It is real handful when managing a dynamic subject, something close in equivalance to 600mm with a 2/3" video camera. Another harmonised sighting camera is needed to aquire the aircraft and re-aquire if it is lost from the frame.

The resolution is a bit soft wit this lens.

I have always thought this was typical of the MTO which is quite old. However, I recently discovered that the Nikon mount I have on it appears to have had material skimmed off the face for some reason and backfocus for a Peleng Fisheye was off by 0.2mm when using it.

So I will shim it forward on the MTO and see if this improves things another day.

I substituted this mount on the Peleng because I did not have the correct size grubscrews for the Peleng's own Nikon mount which was otherwise identical in appearance.

For the flying enthusiasts, if you look carefully at the aircraft, you can observe the movements of the control surfaces and even stick movements by the pilot in one of the hammerheads.

The vision suggests that the aircraft is closer to the ground than it really is.

Since the last clip was posted, the propellor on the aircraft has been replaced with a quieter version with slightly coarser pitch. The performance of the aircraft has not been adversely affected but the noise is way down.

FOOTNOTE:

Still images of the rig used for the ground-to-air imaging can be found here :-

http://exposureroom.com/members/DARANGULAFILM.aspx/assets/0f993f3acfe84243a3f9cd2678f8ecfe/
http://exposureroom.com/members/DARANGULAFILM.aspx/assets/7d60e770eb224d6c8705a55bd42cece6/

Play the HD Version (High Bandwidth Required)

Mdsize: 34.07MBwxh: 640x360

Updated: 2 months ago

Short

Genre: Action

Duration: 00:04:57

Definition: This Video is a High Definition (HD) Video

Dimensions: 1280 x 720

Size: 172.83MB

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What tripod did you use to track this plane bob?

Ted.

The tripod is an old black Miller LPT head on alloy sticks with a single moving stage. It is as good as the wooden one because it does not wind up on pan movements then spring back on stops.

For the plane follows, you have to make sure the pan friction is backed right off and must exercise the pan movement in full circles for a minute or so to get the viscous lube evenly distributed around the friction surfaces otherwise you may find a tight spot with one this old.

This one has actually been damaged through having been worked with a dry spot which has galled patches on the faces but it works okay just the same.

My best is actually an older one with three tilt friction controls but there is no lock-off that can be relied upon so the chances of a runaway camera when the back is turned are too much to risk with it.

These old Millers are better in that they don't have a lash (freeplay) zone like some newer brands have when changing direction on the tilt movement.

They also do not have cams or spring counterbalancing so are more controllable when doing tight follows, no chance of the counterbalancing being inadventantly left on if it is not there at all.

Fournier Close Up

Exciting footage, interesting comments on equipment. I often wondered why my Miller DS10 head would carry on rotating after the event. I had an interest in aviation as a engine technician & cadet Flight E forty years back !! Cheers.

Ron

If you were an engine tech then you would have been rapt with the Fournier starting system.

It is like the biggest Briggs and Stratton lawnmower cable and handle pull-starter in the entire universe. The pilot does his checks, climbs in, straps in, pulls the handle and it goes.

Apparently with a new tight engine, it can be a bit of an effort which led to an electric start version.

The older tripods and legs were intended for heavier cameras and themselves are quite heavy. Given a choice of scrambling up the hill with a DS10 or the old one, I think I would pick up the DS10.

RON AND TED

Two photos of the rig used to do the ground-to-airs can be found here :-

http://exposureroom.com/members/DARANGULAFILM.aspx/assets/0f993f3acfe84243a3f9cd2678f8ecfe/

http://exposureroom.com/members/DARANGULAFILM.aspx/assets/7d60e770eb224d6c8705a55bd42cece6/

You'll have to copy and paste the links to your browser as I don't know how to do the href thing on this site to make clickable links of them.

FOURNIER CLOSE-UP

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