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Tools & Techniques for Nature, Outdoors, Wildlife & Underwater Videography.


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Old December 24th, 2007, 06:47 PM   #1
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Not all about wingspan, but how to use it

First clip from Crete, second from Spain, third from Bulgaria ...

http://www.stage6.com/user/videorapt...ard-for-3-mins
http://www.stage6.com/user/videorapt...t-at-Monfrague

http://www.stage6.com/user/videorapt...ings-in-a-gale

Happy times
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Old December 25th, 2007, 07:40 AM   #2
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Brendan,

Merry Xmas and thanks for sharing those clips with us, I am wondering if you remember what shutter speed the Crete clip was shot at, it appears to have a stuttering effect which could be caused by a high shutter speed, maybe a ND (Neutral Density) filter should have used instead of increasing the shutter speed.

Your point about the larger birds flying in high winds, is also relevant when it comes to filming any size bird, it is always better to be up wind on a bird as it will generally face into the wind.

I was lucky enough to see Giffon Eagles in southern France around the Gorges du Tarn

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Old December 25th, 2007, 08:35 AM   #3
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Good to hear from you Bob.

I'm guessing that 1/50, being default, was my shutter speed on these 3 clips. But I would say that the ND filter warning was ignored ... I used to do that until recently. Which doesn't answer any questions really but you have raised a point that has intrigued me for 5 years ... so many contributors to this forum seem to be saying that the only way to learn videography is to practice it that I find it extremely difficult to read anything that states specifically not only what the pros & cons are for a particular shooting decision or action but what the original purpose of a specific effect or mechanism is intended to be.

Your statement ..... " maybe a ND (Neutral Density) filter should have used instead of increasing the shutter speed" .... raises the possibility that you can tell me what the specific purpose of an ND filter is? And while you're at it maybe you can tell me the name of practical publication(s) that give real insight into the original uses/purposes of the numerous mechanisms built into recent & modern camcorders. I can't understand why the manufacturers run away from this side of their business ... product information at consumer level. Yes I have read the manuals but they are entirely data-bound ... mention of uses and purposes, advantages and benefits are almost ignored. It is assumed that everybody knows them from college or bitter experience or from mixing with the "fraternity".

Any help would be greatly appreciated.
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Old December 25th, 2007, 08:55 AM   #4
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From Wikipedia:

Neutral density filter

In photography and optics, a neutral density filter or ND filter is a "grey" filter. An ideal neutral density filter reduces light of all wavelengths or colors equally. The purpose of standard photographic neutral density filters is to allow the photographer greater flexibility to change the aperture or exposure time, allowing for more control, particularly in extreme circumstances.
For a transmissive ND filter the amount of optical power transmitted through the filter is given by:
Fractional Transmittance = 10-ND
For example, on a very bright day, one might wish to photograph a waterfall at a slow shutter speed to create a deliberate motion blur effect. In order to do this, one would need a shutter speed on the order of tenths of a second. There might be so much light that even at minimum film speed and a minimum aperture such as f/32, the corresponding shutter speed would still be too fast. In this situation, by applying an appropriate neutral density filter one or more stops can be taken out of the exposure, allowing a slow shutter speed and more pleasing effect.
Another use of neutral density filters is in controlling exposure with mirror-lenses catadioptric optics, since the use of a traditional iris diaphragm increases the ratio of the central obstruction found in those systems leading to poor performance.
A graduated ND filter is similar except the intensity varies across the surface of the filter. This is useful when one region of the image is bright and the rest is not, as in a picture of a sunset.
Another type of ND filter configuration is the ND Filter-wheel. It consists of two perforated glass disks which have progressively denser coating applied around the perforation on the face of each disk. When the two disks are counter-rotated in front of each other they gradually and evenly go from 100% transmission to 0% transmission. These are used on catadioptric telescopes mentioned above and in any system that is required to work at 100% of its aperture (usually because the system is required to work at its maximum angular resolution).


A ND4 filter.
Practical ND filters are not perfect as they do not reduce the intensity of all wavelengths equally. This can sometimes create color casts in recorded images, particularly with inexpensive filters. More significantly, most ND filters are only specified over the visible region of the spectrum, and do not proportionally block all wavelengths of ultraviolet or infrared radiation. This can be dangerous if using ND filters to view sources (such as the sun or white-hot metal or glass) which emit intense non-visible radiation, since the eye may be damaged even though the source does not look bright when viewed through the filter. Special filters must be used if such sources are to be safely viewed.
ND filters find applications in several high-precision laser experiments. This is because the power of a laser cannot be adjusted without changing other properties of the laser light (e.g collimation of the beam). Moreover, most lasers have a minimum power setting at which they can be operated. To achieve the desired light attenuation, one or more neutral density filters can be placed in the path of the beam.
ND filters are quantified by their optical density and in photographic terms produce f-Stop reduction as follows:
Filter Factor (NDx) Filter Optical Density f-Stop Reduction % transmittance
2 0.3 1 50%
4 0.6 2 25%
8 0.9 3 12%
64 1.8 6 2%
1,000 3.0 10 <0.1%
10,000 4.0 13
1,000,000 6.0 20
Another practical way of determining what type of ND filter to use is by the percent of light that the filter allows to pass (transmittance). This parameter is typically applied to microscopy applications versus photography applications. Here is a more complete list of Filter Optical Density versus percent light transmitted: [1]
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Old December 25th, 2007, 04:49 PM   #5
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Thank you for that prompt Kevin. The paragraph that reads: "For example, on a very bright day, one might wish to photograph a waterfall at a slow shutter speed to create a deliberate motion blur effect. In order to do this, one would need a shutter speed on the order of tenths of a second. There might be so much light that even at minimum film speed and a minimum aperture such as f/32, the corresponding shutter speed would still be too fast. In this situation, by applying an appropriate neutral density filter one or more stops can be taken out of the exposure, allowing a slow shutter speed and more pleasing effect." seems to be relevant to some situations I meet and adaptable to other situations.

When read in conjunction with Bob Thompson's statement: "I am wondering if you remember what shutter speed the Crete clip was shot at, it appears to have a stuttering effect which could be caused by a high shutter speed, maybe a ND (Neutral Density) filter should have used instead of increasing the shutter speed." it suggests that "shutter speed" should be my next line of enquiry ... wikipedia had interesting things to say about that too. It does prompt the question "What shutter speed were you using, Bob, for that super white pelican clip?" But your Arriflex camera is something special and so far out of my league that the answer may not be relevant to my XM2. I hope I'm wrong.

Anyway, I am now asking both of you and anyone else with insight into bird flight footage to tell me what should happen if I pan big bird flight at 1/12 sec. instead of my usual 1/50 ... specifically, will a solid background (cliff or hillside) appear (out of focus but) smooth ? and will slow wingbeats appear fluttered ?

You might say "Go out and try it and see" but unfortunately there is no access in Ireland to big soaring birds, and when I reach them abroad it's too inefficient to be learning from experience without a monitor other than my LCD.
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Old December 25th, 2007, 05:32 PM   #6
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Brendan,
I think you're asking what 10 wise men can't answer! ;-)

The only advise from me is to go out and try it out yourself. Even if you don't have any "big soaring birds" you have access to gulls in Ireland don't you? Gulls rides the wind in a fine way to practice IMHO. Find a windy day, go to the shore, take with you an assistant with lots of bread which he throw up in the air, and you're done!
I'm also not sure that your XM2 is capable of doing what you're trying to do(sorry to say!).

New camcorders arrives almost everyday now, they have something called variable frame rate. I think your best bet will be to research them. Both Sony and Panasonic (others will soon come too) have those camcorders which will make your life easier, Brendan.
The trick here will be to increase the frame rate to 40-60 frames per second, when trying out different shutter speeds, I have seen some amazing demoreels of this and without promise you anything I will definitive have tried out this!

Note that this is high end camcorders which produces huge filesize (no tape any longer but cards and disk solutions) and they require strong editing suites with lots of RAM and diskspace.
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Old December 25th, 2007, 08:07 PM   #7
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Brendan,

As per said, go out an d practice.

However:

Shooting at slower speeds will put blur into the pictuer!!

If you are shooting slow, but are panning evenly with the eagle then the background will blur out and the wing movements wil slighlty blur in relationship to how slow you are shooting!!!!

sometimes you can shoot and have the near stationary head infocus as you stay with it and have wingtips blurring into the background, it looks rather cool rreally.

when we watch raptors/birds fly we do not ever see clear wing movement, it is always blurred to some degree. So when I shoot I want to shoot so that it looks as i would actually see it. The variation of movement will be best shot between 1/30th to 150th, depending on the effect you want to see.

this is where per's advice comes into play, go practice and record verblly onto tape what you are doing.

Generally under most daylight If youa re shooting at these slower shutter speeds you will have smaller aperatures that will give you greater depth of field, hence more of the image area will be focused at the given focal length you have it set for!

I almost always shoot with the neutral density on when I am shooting into the sky.

I would bet your film that the stacatto look on the footage was from using to fast of a shutter speed. A slower shutter speed will just blur out!!

curiously, are you shooting in progressive or interlaced???



I also recomend you download virtualdub, and the deshake program and try using it on the first part where it was a little shakey!!!!


Thanks for sharing the clips!!! I really enjoy them!

Curiously, do you set your gl2 on a shoulder mount to help you steady it???
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Old December 25th, 2007, 11:33 PM   #8
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Brendan,

For your information, the Dalmation Pelican shot was filmed on a Sony D600 SP camcorder and the shutter was set at 1/50 sec and a ND filter was used so that the Canon 300mm lens was at around f5.6 - 8 as this is the aperture, which IMHO gives the sharpest pictures on this lens.

I always use 1/50 sec as I find using a higher shutter speed I may obtain sharper individual frames, but when played back it can produce a "stuttering effect".

When shooting on film I would increase the frame rate (frames/sec) up to 50 frames per second or higher so you can have a beautiful slow motion shot.

Bob
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Old December 26th, 2007, 02:37 AM   #9
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Quote:
Originally Posted by Bob Thompson View Post
When shooting on film I would increase the frame rate (frames/sec) up to 50 frames per second or higher so you can have a beautiful slow motion shot.
BINGO! Brendan there you see what Bob do on film, which support my theory (look above)!
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Old December 26th, 2007, 06:34 AM   #10
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Quote:
Originally Posted by Per Johan Naesje View Post

..........I'm also not sure that your XM2 is capable of doing what you're trying to do(sorry to say!).

New camcorders arrives almost everyday now, they have something called variable frame rate. I think your best bet will be to research them. Both Sony and Panasonic (others will soon come too) have those camcorders which will make your life easier, Brendan.
The trick here will be to increase the frame rate to 40-60 frames per second, when trying out different shutter speeds, I have seen some amazing demoreels of this and without promise you anything I will definitive have tried out this!

Note that this is high end camcorders which produces huge filesize (no tape any longer but cards and disk solutions) and they require strong editing suites with lots of RAM and diskspace.
and when Bob Thompson wrote ....
"I always use 1/50 sec as I find using a higher shutter speed I may obtain sharper individual frames, but when played back it can produce a "stuttering effect".

When shooting on film I would increase the frame rate (frames/sec) up to 50 frames per second or higher so you can have a beautiful slow motion shot."

..... he was doing 2 things I need to see contrasted , side by side, shutter speed and frames per second, AND he was probably talking about camcorders like his Sony D600.

Tell me please why the XLH1 is excluded from consideration for this exercise?
How limited is the frame rate on XLH1? [I believe my XM2 is limited to 25fps ] If XLH1 is similarly limited or nearly as limited I might as well forget about XLH1 and think about Sony and Panasonic? Is this true advice for my type of flight footage ?? I smell a sharp price rise in the air! [I have 400 Gigs + 200 + 100 on drives. How much spare Gigs do I need?
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Old December 26th, 2007, 07:40 AM   #11
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Hi Brendan.
I guess you live in PAL-land?

XLH1 got these settings:
Frame rate is 50 fps/intelaced mode (same as TV-signals) or 25 fps output signals converted into 50 fps intelaced.

Shutter speed it depends on how you use it, but it goes from 1/3 to 1/16000.
When it comes to shutter speed I almost shoot in 1/50.

You can't shoot slow motion with the XLH1. This you have to do in post, sorry about that.

The reason I bought this camera, is because I can change to different lenses.
A huge benefit in wildlife video.

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Old December 26th, 2007, 07:42 AM   #12
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Quote:
Originally Posted by Brendan Marnell View Post
Tell me please why the XLH1 is excluded from consideration for this exercise?
How limited is the frame rate on XLH1? [I believe my XM2 is limited to 25fps ] If XLH1 is similarly limited or nearly as limited I might as well forget about XLH1 and think about Sony and Panasonic?
Well, the XLH1 have exactly the same frame rate as your XM2, albeit I'm not sure about the progressive alternatives (in PAL-world 25f) on the XM2 if present at all?
The XLH1 is a magnificent camcorder, that for sure. And I love this camcorder for it's daily work, but for special recordings like what you are trying to archieve, I think even the XLH1 will suffer! Also the highly compressed HDV Mpeg2 codec, gives you sometime headache when you try to succeed in glorious pans without any motion blur and artefacts. The more motion the harder things become. I have tons of rejected footage laying in the trashcan due to this!
Luckily the technology improve even in our price level and as said before some brands like Panasonic and Sony have put on the market some really interesting products recently.

Quote:
Originally Posted by Brendan Marnell View Post
Is this true advice for my type of flight footage ?? I smell a sharp price rise in the air! [I have 400 Gigs + 200 + 100 on drives. How much spare Gigs do I need?
Don't think that exhanging solely the camcorder will give you an easier life Brendan! As said new technology induce new challenge in the chain.
New gear will introduce new codecs and formats, no more tapes for backup but everything has to be stored on disks. Huge disks!
Wildlifephotographers like myself want to store most of the footage we record for our stock library and future productions. It's not only about good skills in front of the camcorder any more but also having a degree as a chief engineer in computer engineering too!

I can not tell you if your gigs of drives will do nor if your computer will have the power to handle the amount of datastream new systems and codecs needs. You are on Adobe Premiere Pro? The most popular editing suites will certainly hang on the race of new codecs in the future. Old PC's don't.

Speaking for myself I have a brand new Mac Pro stuffed with the hottest accessories and software of today, being shipped to me as we speak. This is a major upgrade for me as I'm going to make wildlifefilming for my living in the next years to come. In my budget I've will be planning major upgrades every 2-3 years or so... ...what's our workingplattform today is not what we're working on tomorrow.
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Old December 26th, 2007, 08:22 AM   #13
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So, it boils down to this:-

All modern camcorders have lots of shutter speed & DOF, x10 or (much) more optical zoom, plus mics + shoes + lots of pre-set modes, other options and gadgets. Whether they have CMOS or 1 to 3 ccd chips and the chip-size does seem to be vital for image quality but there's a fair amount of discussion on DVInfo about that ... what a pity there are not comparative clips on DVInfo illustrating the real differences in quality, side by side!

Many modern camcorders have NEITHER variable frame rate NOR interchangeable lens facility ...

Now my search begins for a cam with those 2 vital ingredients .... any suggestions please? And probably HD as well. Any recent conclusions on the debate between CMOS and ccds also welcomed.
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Old December 26th, 2007, 12:41 PM   #14
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Brendan,

When I shot film with my bolex I shot at 64 frames a second and that was not to bad. Bob's comment is dead correct.

Sony fx7 and a couple other sonys have variable frame rates for up to something like 6 seconds.

I thought this was brillant but upon further research found that the quality of the footage suffers rather dramaticly.

I was ready to jmp right in there!!!

It looks like it may be a few years beofre the perfect that at a price we could afford and still have quality video.

Perhaps someone on this list has one and could post some slow mo footage from them for a comparison.
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Old December 26th, 2007, 04:13 PM   #15
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Quote:
Originally Posted by Per Johan Naesje View Post
.............Speaking for myself I have a brand new Mac Pro stuffed with the hottest accessories and software of today, being shipped to me as we speak. This is a major upgrade for me as I'm going to make wildlifefilming for my living in the next years to come. In my budget I've will be planning major upgrades every 2-3 years or so... ...what's our workingplattform today is not what we're working on tomorrow.
..... Wildlifefilming for your living! great news and good for you, Per Johan.

If you become interested in big birdflight I should be delighted to learn from your efforts and experience; so don't disappear into the snowmelt up there and make a meal for a polar bear.
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