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#16 |
Obstreperous Rex
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Sorry but this is incorrect. When shooting through 35mm still photo lenses with the Canon EF to XL adapter on the Canon XL H series camcorders, the crop factor is 7.2 times in HD or DV widescreen 16:9 mode, and 8.8 times in DV standard 4:3 mode. Assuming that Dan chooses to shoot in HD, the field of view through his 300mm lens would be equal to a 2100mm+ lens (in still photo 35mm terms). Hope this helps,
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#17 |
Major Player
Join Date: Nov 2009
Location: White Rock
Posts: 254
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Thanks Chris,
To be fair to you and me, I should say that it would be much better (fair again and respectful) if you did not missed the part in brackets from my post in fairness to my honesty, but, I thank you for your post and your honesty. Cheers |
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#18 |
Inner Circle
Join Date: Dec 2003
Location: PERTH. W.A. AUSTRALIA.
Posts: 4,476
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Dan.
Attention deficit crept into my earlier response. I forgot you were going to be on top of the building. I agree, a high vantage point will create a much more pleasing motion shot shortly after liftoff as the background reference for motion will remain in frame longer, maybe even enough to show the rate of accelleration. I would still be a bit iffy about using image stabilisation. It would depend on the building vibration. I.S. could help but might aggravate once you throw in the tilt motion as well. If it is a clean slow bounce of about a half-second period, the I.S. may keep up. If there are other vibrations with shorter periods in the mix, the IS might get confused and amplify some combinations. In-camera I.S. is optimised for the most common lens the camera will wear. I think that with a long lens, you will introduce a "hopping" artifact as the I.S, offset reaches its limit with the tilt, then moves to "catch up" and then dwell again through to its travel limit to hold the subject, then hop forward again. Image stabilisation is intended to help you handhold on a fixed or minimally moving subject without shaking. I really would not use it. Try to find a corner of the building to set your tripod up on rather than in centre of the edge. That way you can have two legs closer to an edge on parts of the floor that are not bouncing as much and the third leg will be on a steady point in the corner or as steady as it gets. It becomes a bit awkward for follows if you do this because you confine your walkspace and you may go over the rail if you are not careful if you are forced to try a horizontal follow. Being above the longer corner-to-corner line of the structure also means that the angular deflection should be less. Last edited by Bob Hart; May 10th, 2010 at 08:56 PM. Reason: error |
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#19 |
Trustee
Join Date: Sep 2006
Location: Montreal, Quebec, Canada
Posts: 1,138
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What About That Guy In Northern Sweden ?
Hey Dan:
Do you remember the guy who was shooting the utterly A M A Z I N G extreme Northern wildlife programs with the XL H1 in 90 mile per hour 60 below zero Farenheight Arctic conditions while recording HDV tape in camera using extremely long telephoto lenses on special - custom made metal camera and lens cradles ? This guy was shooting extremely fast moving and elusive subjects at incredible focal lengths ! I think this man would be worth contacting on this subject. I consider his wildlife footage to be at national Geographic level ! I mean this guy made this type of difficult videography look easy ! I'm sorry, but his name escapes me at the moment of writing this post, but I'm sure a search of the older Canon XL H1 threads will yield his name and links to his wildlife shot with both the stock 20X and Canon and Nikon 35 mm telephoto lenses on those custom lens cradles mounts. I hope this helps. |
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#20 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
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Dear Bob,
Thank you for your input. The VAB is, internally, a building made of 6 separate towers, each approximately 520 feet tall. The roof covers all 6 towers, and is about the size of a large city block. It is very interesting to speculate which part of the building would have the least vibration. The corners may have extra vibration due to the buffeting of the winds, (This is pure speculation). (I do not remember any vibrations, but the last time I was up there was 43 years ago!) My first place to test on Thursday will be near the elevator shaft. I will also test near the corners thanks to your suggestion. I can be very portable, except for my 24" monitor, which needs 110 volt power. It will also run off 24 V DC, but I am not setup to power this monitor on batteries. I expect the few power outlets to be near the elevator shaft. As you can probably tell, I am very excited about visiting the cape again after all of these years. It was very exciting to be part of the Apollo program. I feel that most people who look back on it today are amazed as what was actually accomplished. I was extremely lucky to be part of the project, and to be in a very small group that touched so many areas. I was in Launch Vehicle Operations, Guidance and Control, Flight Control Systems Section. I worked with far more senior engineers. In Flight Control we prepared, checked out, and tested the Flight Control Computer. This controlled the gimbling (swiveling) of the engines, the shutoff of the engines of each stage, the ignition of the engines on the next stage and many other functions. Thus I got to be involved in most of the launch vehicle, but had no access to the Command or Service Modules. One the main tasks of the Flight Control Computer was to perform the calculations to achieve the proper trajectory. Our computer took inputs from another computer, which was programmed to know where the vehicle should be. Our computer took these inputs, and inputs from an inertial navigation platform, then calculated what it would take to perform the mission, with knowledge of the vehicle, current conditions, etc. To get to the moon, we had to be at a specific point in space, pointed in a specific direction, at a specific time, and going a specific speed. All of this was calculated on-board, not relying on instructions from the ground. All of this was accomplished without microprocessors, which were not invented yet.
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Dan Keaton Augusta Georgia |
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#21 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
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Dear Mark,
I am assuming you are referring to Per Johan Naesje.
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Dan Keaton Augusta Georgia |
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#22 |
Inner Circle
Join Date: Dec 2003
Location: PERTH. W.A. AUSTRALIA.
Posts: 4,476
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If the elevator shaft is a free standing stiff structure like a concrete column within the tower, I would be inclined to use structure attached to that.
However, if the lift tower is inside and a part of a metal lattice support column, I would choose the top of the column furthurest from it in case somebody decides to come upstairs during your shoot and shake your camera. I think I would chance a bit of flutter from passing wind on a corner than risk vibration from the overpressures coming your way from the launch hammering at the flat surfaces facing the vehicle. If there is any significant movement of the corner support structure, I think it will more likely be in a panning movement than a tilting movement. At the end of all this, please don't keep your footage hidden away but let us see it. |
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#23 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
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Dear Bob,
I certainly hope to be able to share the footage. It certainly does add to the pressure to get this right on the first attempt.
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Dan Keaton Augusta Georgia |
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#24 |
Trustee
Join Date: Sep 2006
Location: Montreal, Quebec, Canada
Posts: 1,138
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That's Him ! :-)
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#25 |
Major Player
Join Date: Jan 2010
Location: Tinton Falls, NJ
Posts: 780
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Acceleration
Hi Dan,
Just guessing (and you probably know more about it than I) that the thrust - and hence the acceleration - will be fairly consistant through most of your shot. This of course means that the speed of your tilt will continue to increase as long as you need to keep the rocket in your sights. Something that we've done in the past to prepare for telephoto CU photography of stunt falls (though obviously in the opposite direction from what you would need) has been to drop traffic cones off the roof of a relatively tall building (7 - 10 stories) to get a feel for the effect of continued acceleration. Being used to the acceleration helps get the shot right on the first take. Best of luck with it! |
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#26 |
Obstreperous Rex
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It will go up and then appear to go over in a curve as it arcs out
easterly over the Atlantic... see attached pic (NASA public image). |
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#27 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
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White Knight to the Rescue
Dear Friends,
I received a very nice call this morning from a person that I never met before, but one who is a great member of the DVInfo.net community. He was reading our posts in this thread an offered to help. He is loaning me a Sony EX3, with the 2/3" lens adapter and a professional 2/3" Canon lens for the shoot on Friday. He is actually loaning us a complete setup, including tripod and nanoFlash! I was stunned. I have been busy all day making the arrangements, but it is now all worked out. All of this generosity and members helping members is a tribute to Chris Hurd and DVInfo.net.
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Dan Keaton Augusta Georgia |
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#28 |
Trustee
Join Date: Sep 2006
Location: Montreal, Quebec, Canada
Posts: 1,138
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Of Course We Will Help :-)
Hey Dan:
I think this thread proves that most of us who participate in this forum really do care about the products, the technology, and are naturally dedicated to wanting to help their fellow videographers move forward. This final Space Shuttle Launch, and the whole space program is historic. The United States is broke, uh, reeeeeeealy broke ! and I fear NASA's manned space program's future is pretty uncertain. (What's it cost to shoot off a shuttle these days ?) - It must be serious cash. I hope you get a perfect shuttle launch sequence. I'm confident you will Dan ! :-) |
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#29 |
Obstreperous Rex
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According to NASA, each shuttle launch costs appx $450 million. This is the final scheduled flight of Atlantis, although upon the completion of this mission it will be processed as if it would go up again, because it will be held ready in a status called "Launch On Need," as a contingency (i.e., rescue mission) should anything go wrong on the remaining two scheduled shuttle flights -- those being STS-133, the final flight of Discovery in September, and STS-134, the final flight of Endeavour in November, which will conclude the 30-year-old space shuttle program.
Dan -- I sure am glad this is working out for you -- see you soon on the Cape, |
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#30 |
Trustee
Join Date: Sep 2006
Location: Montreal, Quebec, Canada
Posts: 1,138
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I Hope They Send Folks to Mars
...Hi Chris: I'm glad that at least they won't scrap the shuttles. If something goes very wrong with the International space station, then they'll need something to get back up there fast. Next stop Mars (I hope). Something completely different for a deep space trip and return will be required. They' will leap frog it over to Mars. (Send a remote control ground module -Read House - to Mars first). Next, they'll send an emergency vehicle half way out to Mars. One ship docks to the next and leaps over to the red planet. Sorry, I digress off topic.
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