Panning Exercise

Quote:

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Originally Posted by Stagecoach

Ted,

fortunately, being an engineer the term angular velocity is relatively easy to consider for me. Perhaps to simplify things when panning a moving subject from a fixed point the angle between sensor and subject change as your body swivels.

The effect of this is that a ‘specific’ point on the vehicle (say door handle) changes from going from a purely right to left direction only to a direction of right to left + moves farther away or closer.

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Yes indeed. I have another analogy which is more extreme that just a car shot.

Standing on a railway platform, a long train is zooming past with the middle of the train before your very eyes. You pan perfectly and speedily with the aforesaid fish-eye lens and later examine the image. Would not the front and the back cars of the train be blurred almost as much as any visible background?

Because of panning, the middle of the train becomes stationary relative to the middle of the image. But the back is now speeding away from the camera, as is the front speeding towards it (both relatively speaking). Irritated, you crop the image so there is only 1ft of train left in the image. Goodbye, motion blur :D

Your car shot must lie between those two extremes, I reckon.

I did a quick calc. A car, going 40 km/h, 5m away from the cam: To freeze the car, the camera is panning approx 2.2 rad/s at the point of aim. But a point on the car 2m back from the point of aim is 'panning' 0.34 rad/sec slower.

I'm sure you all know that 1 rad = 57 degs approx ;-)

Thank you Grahame. Reading this has been very helpful to me. I would use VR if I have it but I don't and I don't think having it makes and difference when using a long lens.

Quote:

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Originally Posted by Stagecoach

Christina,

I think what you have to accept is that there will be a compromise with horses as there is with cars at similar speeds to horses.

My car shots show that there is a great difference in visual appearance of 'speed' between using shutter speeds between 1/40 to 1/200. It's all about compromise and if you look at Manu's shots even at 1/160 he was only able to freeze the two legs that were at the extremities of their movement (against the ground) but the 'speed' aspect was compromised if that what your priority was.

I would suspect that the best motion shots of horses racing with a good motion blurred background are when the majority of the subject is captured with the least number of parts (legs, heads, tails etc) moving in different directions to the main body.

As for where the best compromise is I would suggest somewhere between the minimum SS you can use up to halfway to the shutter speed that freezes too much.

Grahame

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After half a night's sleep, I am up earlier than I should be.

There has to be a simple relationship between the speed of panning, the length of the background streak and the distance of the features to be streaked from the camera, rather than using examples by rote, e.g. running wildlife, horses in a race, cars, racing cars, trains in a station, jets or even props (airscrews).

I'm thinking that the speed of the moving object (Vo) and it's distance from the camera (Do) sets the angular speed of the panning (w). And the background distance (Db) with desired streaks of length (Sb) sets the angle of streak or blur viewed from the camera.

I'll use radians/sec for w and assume small angles of motion blur which is probably good for guessing out in the field.

Speed of panning w = speed divided by object distance from camera = Vo*1000/(Do) = radians/hour divided by 3600 = w rad/sec. Where Vo*1000 = meters per hour, Do is in meters.

A streak Sb at a distance of Db occupies an angle of streak viewed from the camera of Sb/Db.

Shutter speed required is, therefore, angle of streak divided by panning speed = (Sb/Db)/w. That is to say, rad/(rad/sec) = sec.

Lets put an aircraft at 200m away and you want 1m streaks at the same distance at a take-off speed of say 150km/h:

Panning speed = (Vo*1000)/(Do*3600) = 150*1000/(200*3600) = 0.208 rad/sec.

1m streak at 200m = 0.005 rad.

Shutter speed is 0.005/0.208 = 0.024 or about 1/40 sec.

Lets say there is a crowd 10m in front of you and, instead, you desire a head blur of 100mm (0.1m). Angle of streak = 0.1/10 = 0.01 rad.

Shutter speed = 0.01*0.208 = 0.048 or about 1/20 sec.

Lets say instead that there is a Control Tower behind the aircraft at say 500m from the cam and you want to blur it double of it's width, say 60m. Angle of streak = 60/500 = 0.12 rad.

Shutter speed = 0.12/0.208 = 0.576 or 1.7 sec - hmm . . a bit too much blur, I reckon.

Lets say there's a horse 25m away and a fence 5m behind it. You desire 300mm streaks on the fence.

Angle of streak = 0.3/(25+5) = 0.01 rad.

At 40 km/h velocidad del caballo, panning speed is (40*1000)/(25*3600) = 0.44 rad/sec

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

(to get deg/sec from rad/sec multiply by 57)

Ipso fatso, Q.E.D. :)

Quote:

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Originally Posted by xpatUSA

After half a night's sleep, I am up earlier than I should be.

There has to be a simple relationship between the speed of panning, the length of the background streak and the distance of the features to be streaked from the camera, rather than using examples by rote, e.g. running wildlife, horses in a race, cars, racing cars, trains in a station, jets or even props (airscrews).

I'm thinking that the speed of the moving object (Vo) and it's distance from the camera (Do) sets the angular speed of the panning (w). And the background distance (Db) with desired streaks of length (Sb) sets the angle of streak or blur viewed from the camera.

I'll use radians/sec for w and assume small angles of motion blur which is probably good for guessing out in the field.

Speed of panning w = speed divided by object distance from camera = Vo*1000/(Do) = radians/hour divided by 3600 = w rad/sec. Where Vo*1000 = meters per hour, Do is in meters.

A streak Sb at a distance of Db occupies an angle of streak viewed from the camera of Sb/Db.

Shutter speed required is, therefore, angle of streak divided by panning speed = (Sb/Db)/w. That is to say, rad/(rad/sec) = sec.

Lets put an aircraft at 200m away and you want 1m streaks at the same distance at a take-off speed of say 150km/h:

Panning speed = (Vo*1000)/(Do*3600) = 150*1000/(200*3600) = 0.208 rad/sec.

1m streak at 200m = 0.005 rad.

Shutter speed is 0.005/0.208 = 0.024 or about 1/40 sec.

Lets say there is a crowd 10m in front of you and, instead, you desire a head blur of 100mm (0.1m). Angle of streak = 0.1/10 = 0.01 rad.

Shutter speed = 0.01*0.208 = 0.048 or about 1/20 sec.

Lets say instead that there is a Control Tower behind the aircraft at say 500m from the cam and you want to blur it double of it's width, say 60m. Angle of streak = 60/500 = 0.12 rad.

Shutter speed = 0.12/0.208 = 0.576 or 1.7 sec - hmm . . a bit too much blur, I reckon.

Lets say there's a horse 25m away and a fence 5m behind it. You desire 300mm streaks on the fence.

Angle of streak = 0.3/(25+5) = 0.01 rad.

At 40 km/h velocidad del caballo, panning speed is (40*1000)/(25*3600) = 0.44 rad/sec

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

(to get deg/sec from rad/sec multiply by 57)

Ipso fatso, Q.E.D. :)

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No wonder you can't sleep with all that going on inside of your head:D

Can you get all of your subject in focus? I guess so. Can this also be called panning, though it is moving a tad faster than a horse or car?
Shot at 1/320sec, F9 at 135mm. (Nikon D200)

http://i42.tinypic.com/2n1wc4o.jpg

Saab Grippen on take off.

Out of sheer respect for your mathematical genius this weekend I will try to simulate the exact conditions....

[I]Lets say there's a horse 25m away and a fence 5m behind it. You desire 300mm streaks on the fence.

Angle of streak = 0.3/(25+5) = 0.01 rad.

At 40 km/h velocidad del caballo, panning speed is (40*1000)/(25*3600) = 0.44 rad/sec

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

and give it my best effort! Thank you.


There has to be a simple relationship between the speed of panning, the length of the background streak and the distance of the features to be streaked from the camera, rather than using examples by rote, e.g. running wildlife, horses in a race, cars, racing cars, trains in a station, jets or even props (airscrews).

I'm thinking that the speed of the moving object (Vo) and it's distance from the camera (Do) sets the angular speed of the panning (w). And the background distance (Db) with desired streaks of length (Sb) sets the angle of streak or blur viewed from the camera.

I'll use radians/sec for w and assume small angles of motion blur which is probably good for guessing out in the field.

Speed of panning w = speed divided by object distance from camera = Vo*1000/(Do) = radians/hour divided by 3600 = w rad/sec. Where Vo*1000 = meters per hour, Do is in meters.

A streak Sb at a distance of Db occupies an angle of streak viewed from the camera of Sb/Db.

Shutter speed required is, therefore, angle of streak divided by panning speed = (Sb/Db)/w. That is to say, rad/(rad/sec) = sec.

Lets put an aircraft at 200m away and you want 1m streaks at the same distance at a take-off speed of say 150km/h:

Panning speed = (Vo*1000)/(Do*3600) = 150*1000/(200*3600) = 0.208 rad/sec.

1m streak at 200m = 0.005 rad.

Shutter speed is 0.005/0.208 = 0.024 or about 1/40 sec.

Lets say there is a crowd 10m in front of you and, instead, you desire a head blur of 100mm (0.1m). Angle of streak = 0.1/10 = 0.01 rad.

Shutter speed = 0.01*0.208 = 0.048 or about 1/20 sec.

Lets say instead that there is a Control Tower behind the aircraft at say 500m from the cam and you want to blur it double of it's width, say 60m. Angle of streak = 60/500 = 0.12 rad.

Shutter speed = 0.12/0.208 = 0.576 or 1.7 sec - hmm . . a bit too much blur, I reckon.

Lets say there's a horse 25m away and a fence 5m behind it. You desire 300mm streaks on the fence.

Angle of streak = 0.3/(25+5) = 0.01 rad.

At 40 km/h velocidad del caballo, panning speed is (40*1000)/(25*3600) = 0.44 rad/sec

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

(to get deg/sec from rad/sec multiply by 57)

Ipso fatso, Q.E.D. :)[/QUOTE]

Quote:

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Originally Posted by xpatUSA

I'm thinking that the speed of the moving object (Vo) and it's distance from the camera (Do) sets the angular speed of the panning (w). And the background distance (Db) with desired streaks of length (Sb) sets the angle of streak or blur viewed from the camera.

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Congratulations for finding a method independent of focal length.

BUT.

Also consider the visual impact of a streak of a given length (say, 1m) as seen at the same distance from the camera with a short versus a long lens. With the short lens, that streak will occupy a small portion of the lens's field of view. With a long lens, a greater portion.

There are a couple other factors to consider. Imagine you're using a 20mm lens with a subject circling you pretty close (short panning radius) and a background far away (long panning radius). Then you can get your 1m blur with your subject only moving a short distance. On the flipside, with a long lens and a background relatively close to your subject, the distance the background moves will be closer to the distance the subject moves. And the further the subject moves, the less likely they are to have a predictable path. One of many reasons I like short-lens action work.

https://scontent-b-ord.xx.fbcdn.net/...81441800_n.jpg

Note that this is a flash photo, so there's more at work than just the panning technique.

Quote:

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Originally Posted by Christina S

Out of sheer respect for your mathematical genius this weekend I will try to simulate the exact conditions....

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Hopefully, you'll find proof of the pudding . . . ;)

Quote:

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Originally Posted by RustBeltRaw

Congratulations for finding a method independent of focal length.

BUT.

Also consider the visual impact of a streak of a given length (say, 1m) as seen at the same distance from the camera with a short versus a long lens. With the short lens, that streak will occupy a small portion of the lens's field of view. With a long lens, a greater portion.

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Now we see why I prefer angular measure. However, how we get the angle of streak is up to us. Those who are concerned about different 'length' lenses can consider instead the lens angle of view (AOV) for their camera. I will not insult us by stating how we figure that out! When the AOV is known, we can instead define the streak as a fraction of the angle of view. Say it's 70 deg for some lens and you decide you want 3% streaks, then that would be 70*3/100 = 2.1 degs/57 = 0.037 radians.

Quote:

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There are a couple other factors to consider. Imagine you're using a 20mm lens with a subject circling you pretty close (short panning radius) and a background far away (long panning radius). Then you can get your 1m blur with your subject only moving a short distance. On the flipside, with a long lens and a background relatively close to your subject, the distance the background moves will be closer to the distance the subject moves. And the further the subject moves, the less likely they are to have a predictable path. One of many reasons I like short-lens action work.

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You're right, and the formulae do account for different distances between back- or fore-ground and the subject. The special case is when the distances to the subject and our selected surrounding is the same. The formula still works though and the stationary surrounding will still blur.

Quote:

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Note that this is a flash photo, so there's more at work than just the panning technique.

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Yes, that is a complication which I did not address but feel free to do so (I don't use flash much). There is also the complication implied by Andre's aircraft shot where the machine is moving away from the camera in 3 axes: left, up and away. For that particular shot, the aircraft is still going mostly left and the formula would work "close enough for Government Work" (American expression, meaning barely acceptable).

An equally probable complication is when the subject is approaching at a significant angle e.g. car rounding a curve. The speed of the car can not be used to calculate panning speed. A bit of trigonometry would solve that.

Very nice roller shot by the way, does it all without formulae ;)

Quote:

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Originally Posted by Christina S

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

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Christina, I don't want to discourage you but at that shutter speed I will guarantee you a ratio of 100% miss.

Get the sun behind you.
Set camera to Shutter speed priority dial in 125 - 160 shutter speed and ISO100. Find a spot on the track where you would like to take the shot. Focus on that spot and look at the settings the camera gives you. Note the Aperture setting. Change to Manual mode and duplicate the settings you had in Shutter Speed Priority. Set camera to focus tracking.
Wait for your subject to be close to the spot you chose, following the horse (pan) in the viewfinder - forget that little screen at the back of the camera, point and shoot at Continuous high frame rate.

If you still miss it you can blame me. ;)

Quote:

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Originally Posted by RustBeltRaw

https://scontent-b-ord.xx.fbcdn.net/...81441800_n.jpg

Note that this is a flash photo, so there's more at work than just the panning technique.

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Lex,

A brilliant example of "dragging the shutter". This technique is much easier to create long streaks than panning a moving object and shooting without flash. You must remember Lex a flash gives you an effective shutter speed of around 1/10000sec even at a camera shutter speed of 1/30sec. No matter how fast your subject moves when using flash, you need not get a perfect pan on the subject when shooting flash, your subject will be frozen. The only thing you need to get right with this shot is WB and focus.

Edit:

For those wishing to challenge my statement here is the proof.
I went outside in the dark of night with a flash mounted on my camera. Shutter speed 1/60.
I focussed as well as I could, in the dark of night (MF) on a tree about 1m in front of me. Then I took a golf type of swing with the camera against my body and as I was facing the tree I released the shutter. Effectively the tree was moving at a speed only Ted will be able to calculate, it might not be a perfect in focus shot but, does it look like the tree is in motion?


http://i41.tinypic.com/nwzmle.jpg

Hi Christina, Ted, Lex and Andre

Firstly, apologies for starting a thread that has caused sleepless nights and mathematics:)

Ted,

As you have shown so well mathematics can demonstrate and assist in understanding exactly what is happening and why. Your effort has to be commended and I have very much appreciated reading this.

Andre,

Nice capture but I would question if it is in fact 'all' in focus. If I had looked at this image prior to this thread subject I would have not really taken any account that parts are less sharp than others and if I did I would have immediately thought DoF. As I look at it now I ask myself 'is it all in focus but some parts suffering from motion blur more than other parts'?

Lex,

As you point out there are many variables to consider.

Christina,

I have undertaken a bit more investigation on panning and found a very good article by John Jovic of Photo Cornucopia at
http://photocornucopia.com/1042.html and whilst in reference to cars has some interesting information on panning.

He also gives a 'starting point' for selecting shutter speed which is if the speed is known in kph convert it to mph and use that as the shutter speed. Example if the car is going at 60kph (40 mile per hour) then shoot at approx 1/40th of a second. On this basis as a starting point I would suspect a higher speed is required due to a horse having more out of direction parts flying around that need to be frozen with a higher SS.

Andre has given one example of setting up for your shots so out of interest this is what I did for the cars;

Focus mode in AF-C (continuous) with Dynamic 9 point selected.
For exposure my shutter speed was my priority so I set up in manual with auto ISO. I focused/metered on a point (the road) where I would be shooting and then adjusted my aperture so that the ISO just went above base value, in other words auto ISO would function nearer to rather than farther from base value.
Shooting conditions were between slight cloud to brilliant sun with the sun to left and front of me, not best but for just about every shot any highlights on bright shiny surfaces were just about totally eliminated with around up to 25% recovery only in ACR.

I did find that for using wide apertures and I only went to f4.5 I did have to use either a CPL or on the second day my ND filter to achieve the speeds I required.

Grahame

Hi Grahame,

Thank you for the extra tips and the very informative article, the latter which I will read a few times before this weekend.

So far the best backgrounds I've managed are with a SS of 50, so as hard as it is I am will try that SS again next time around.

Quote:

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Originally Posted by Stagecoach

Hi Christina, Ted, Lex and Andre

Firstly, apologies for starting a thread that has caused sleepless nights and mathematics:)

Ted,

As you have shown so well mathematics can demonstrate and assist in understanding exactly what is happening and why. Your effort has to be commended and I have very much appreciated reading this.

Andre,

Nice capture but I would question if it is in fact 'all' in focus. If I had looked at this image prior to this thread subject I would have not really taken any account that parts are less sharp than others and if I did I would have immediately thought DoF. As I look at it now I ask myself 'is it all in focus but some parts suffering from motion blur more than other parts'?

Lex,

As you point out there are many variables to consider.

Christina,

I have undertaken a bit more investigation on panning and found a very good article by John Jovic of Photo Cornucopia at
http://photocornucopia.com/1042.html and whilst in reference to cars has some interesting information on panning.

He also gives a 'starting point' for selecting shutter speed which is if the speed is known in kph convert it to mph and use that as the shutter speed. Example if the car is going at 60kph (40 mile per hour) then shoot at approx 1/40th of a second. On this basis as a starting point I would suspect a higher speed is required due to a horse having more out of direction parts flying around that need to be frozen with a higher SS.

Andre has given one example of setting up for your shots so out of interest this is what I did for the cars;

Focus mode in AF-C (continuous) with Dynamic 9 point selected.
For exposure my shutter speed was my priority so I set up in manual with auto ISO. I focused/metered on a point (the road) where I would be shooting and then adjusted my aperture so that the ISO just went above base value, in other words auto ISO would function nearer to rather than farther from base value.
Shooting conditions were between slight cloud to brilliant sun with the sun to left and front of me, not best but for just about every shot any highlights on bright shiny surfaces were just about totally eliminated with around up to 25% recovery only in ACR.

I did find that for using wide apertures and I only went to f4.5 I did have to use either a CPL or on the second day my ND filter to achieve the speeds I required.

Grahame

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I think everybody on this thread is making it harder than what it is. The gentleman who had a sleepless night and then went into a big calculation which you won't see in any book and a pro photographer would clearly not use. Panning is a practise and practise and out of 10 images you might have one that is ok. if you use a high ss all you will get is a car/horse/plane or whatever stuck as if somebody had stopped the object dead. Use a low SHUTTER SPEED and you will get the desired images and when you pan start at 180% then take your image at 90% and then keep panning to 0%. Simple.
Dave.

Hi Andre,

No worries... I like a challenge... I will try again this weekend, and if I have a chance I will try your recommendation as well. The problem is that I have only two more tries until the season is over and then I will have to wait until Spring to try again and I only have two tries for each race (8 in total) so indeed it is a challenge.

While of course I would love to have the entire horse in sharp focus I don't think that is possible in combination with a very streaked blurred background. I would be happy with an artistic type photo with just the horses head in sharp focus, which I have almost managed at a slow shutter speed but not quite, and I have seen others manage it with a super slow shutter speed hence my quest to give it a try.

Andre, while your plane shot is wonderful but it does not have the blurred background I am trying for. And yes, your plant photo provides a sense of motion but again it is not the type of background that I am trying to achieve.

On my first try I used a SS of 160 and none of the backgrounds are streaked or blurry and as you can see the background is very unattractive. All of my shots at the horse races with faster shutter speeds (80-160) have a background like this one. It could be my panning skills but as this is new to me I'm not sure, so I'll just have to keep trying. With respect to the sun behind my back I just have to find the best position I can... I would lie down on the track to blur the backgrounds if they would let me on the track but alas they will not.

SS 160 F 18 iso 320

http://backup.cambridgeincolour.com/...s-5160copy.jpg

I don't think it is possible to get this type of sharp focus (SS 2500 F4 iso 800) with panning at low shutter speed, combined with a blurred background (not here). If it is please advise.

http://backup.cambridgeincolour.com/...-62500copy.jpg

My best shots managed so far are with slow shutter speeds of 40- 60, and while far from perfect I think they show that it is possible to get focus on portions of the photo with super slow shutter speeds.

SS 60 F4 iso 450 (note the streakier background in both photos... yet the background is still distracting and is not streaked/blurred enough)


http://backup.cambridgeincolour.com/...es-760copy.jpg


http://backup.cambridgeincolour.com/...s-1260copy.jpg

My best background so far with so/so focus is this one, and this is the type of shot that I am striving for, albeit with sharper focus on the horses head and ideally the eye. Hence, I am going to try a SS of 40 once more which corresponds very nicely with Ted's mathematical analysis... even though it might be my panning skills, I'm not sure because this is still new to me.

SS 40 F4 iso 280

http://backup.cambridgeincolour.com/...s-1340copy.jpg

I am using Continuous Auto focus, single point which I'm trying to hold on or near the horses eye. Thus far I have been trying to hold the focus and fire off as many shots as I can manage while I pan as smoothly as possible.

However, just last week I watched a video in which the photographer would pan using auto focus, press the shutter button just once and pan with the camera after that single click. Are you familiar with this technique of panning? If yes, please share.

Anyway, I hope this gives you a better understanding of what I am trying to do. I want a beautiful streaked background with at least the horses head in sharp focus, and although I have not quite managed it I think that the last image shows that it is possible if I can fine tune my technique...

PS Grahame... My apologies for posting so many photos on your thread but I'm hoping to figure this out soon, before the season ends and trying to figure out as much as I can in as short a time as possible.

Quote:

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Originally Posted by AB26

Christina, I don't want to discourage you but at that shutter speed I will guarantee you a ratio of 100% miss.

Get the sun behind you.
Set camera to Shutter speed priority dial in 125 - 160 shutter speed and ISO100. Find a spot on the track where you would like to take the shot. Focus on that spot and look at the settings the camera gives you. Note the Aperture setting. Change to Manual mode and duplicate the settings you had in Shutter Speed Priority. Set camera to focus tracking.
Wait for your subject to be close to the spot you chose, following the horse (pan) in the viewfinder - forget that little screen at the back of the camera, point and shoot at Continuous high frame rate.

If you still miss it you can blame me. ;)

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Hi Dave,

Do you think that the shutter speed I am using of 1/40 - 1/60 per second is reasonable (assuming that with more practice my panning skills will improve)

What are your thoughts on panning trying to squeeze of as many shots after grabbing focus and panning versus just squeezing off one shot on auto focus and just following through with a pan after that shot? Does this fit with your statement..

Use a low SHUTTER SPEED and you will get the desired images and when you pan start at 180% then take your image at 90% and then keep panning to 0%. Simple.

Thank you.

PS Yes, we may be making it harder than it is, especially if panning is simply an art that one gets better at with practice.. Still that said I think understanding the science behind everything is a good thing and might help one reach their goal a little quicker. :) albeit tired for lack of sleep...

Quote:

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Originally Posted by Dusty

I think everybody on this thread is making it harder than what it is. The gentleman who had a sleepless night and then went into a big calculation which you won't see in any book and a pro photographer would clearly not use. Panning is a practise and practise and out of 10 images you might have one that is ok. if you use a high ss all you will get is a car/horse/plane or whatever stuck as if somebody had stopped the object dead. Use a low SHUTTER SPEED and you will get the desired images and when you pan start at 180% then take your image at 90% and then keep panning to 0%. Simple.
Dave.

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Quote:

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Originally Posted by Stagecoach

. . .I decided to have an attempt at panning cars to look at the motion blur characteristics. . .Why when my panning was good are some areas of the car sharp with others blurred (except wheels) when it cannot possibly be due to DoF? . . .

Anyway, to investigate further I undertook another session today and am convinced it's due to movement in the vehicle bodies in a different direction to the right/left direction caused by suspension and not too perfect road condition. But I'm open to other ideas.

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For these examples - I concur, definitively.

Forensic examination of these three enlarged sections of the image of the white van is just one example:


EXAMPLE 01
http://i39.tinypic.com/2e4dq4y.jpg

Note the leading and trailing edges of the white number plate indicating the forward and downward lurch of the van, (pivoting at or about the point of front wheels - pivot point is shown in another enlargement, below).

***

EXAMPLE 02
http://i44.tinypic.com/33a73ph.jpg

Note in the printing there is little or no leading edges that indicates very little if any perceivable vertical movement of the camera or of the Subject. Note also in the door gap there is no leading edge which indicates that the panning speed is consistent with the vehicle speed.

***

EXAMPLE 03
http://i39.tinypic.com/xcoozl.jpg

Note the door frame gap and how the gap’s leading edge gets bigger as we follow the line of the gap as it moves to the front of the vehicle and thus further away from the pivot point of the downward and frontward lurch of the vehicle.

WW

Hi Bill,

Can you simplify/clarify this statement for me... I would like to understand this better so I can figure out if my panning speed is consistent with my horses, or not, or close, etc...

Note in the printing there is little or no leading edges that indicates very little if any perceivable vertical movement of the camera or of the Subject. Note also in the door gap there is no leading edge which indicates that the panning speed is consistent with the vehicle speed.


Thank you.

Quote:

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Originally Posted by William W

For these examples - I concur, definitively.

Forensic examination of these three enlarged sections of the image of the white van is just one example:


EXAMPLE 01
http://i39.tinypic.com/2e4dq4y.jpg

Note the leading and trailing edges of the white number plate indicating the forward and downward lurch of the van, (pivoting at or about the point of front wheels - pivot point is shown in another enlargement, below).

***

EXAMPLE 02
http://i44.tinypic.com/33a73ph.jpg

Note in the printing there is little or no leading edges that indicates very little if any perceivable vertical movement of the camera or of the Subject. Note also in the door gap there is no leading edge which indicates that the panning speed is consistent with the vehicle speed.

***

EXAMPLE 03
http://i39.tinypic.com/xcoozl.jpg

Note the door frame gap and how the gap’s leading edge gets bigger as we follow the line of the gap as it moves to the front of the vehicle and thus further away from the pivot point of the downward and frontward lurch of the vehicle.

WW

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Quote:

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Originally Posted by Christina S

Can you simplify/clarify this statement for me... I would like to understand this better so I can figure out if my panning speed is consistent with my horses, or not, or close, etc...

Quote:

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Note in the printing there is little or no leading edges that indicates very little if any perceivable vertical movement of the camera or of the Subject. Note also in the door gap there is no leading edge which indicates that the panning speed is consistent with the vehicle speed.

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Hi,
Try this:

Look carefully at the EXAMPLE 01.
See how there is a leading edge of the WHITE Number Plate (Car Licence Plate) - it is blurred but if you look closely it appears as though there are actually three plates - you can see the edges.
Notice how these leading edges move forward and also downward.
These edges are a strong (courtroom evidence strong) indication that the NUMBER PLATE is moving (slightly faster than the PANNING SPEED and also that the NUMBER PLATE is definitely moving DOWNWARD (i.e. Vertically).

Now look at the EXAPMLE 02.
And carefully look at the blue writing in the sign and note that there is none or very little leading edges VERTICALLY - this is evidence that the car at the middle are is NOT moving up or down (i.e. vertically) and also that the panning movement is very even in an HORIZINTAL movement.

The door frame (in EXAMPLE 02) is just about vertical so look closely at the THICKNESS of it and note how it appears a consistent thickness from top to bottom, which is (when we COMPARE IT TO EXAMPLE 03) is another indication that the PANNING speed is consistent with the VEHICLE speed.

Now look at the ALL the door frame in EXAMPLE 03.Note how it becomes THICKER where the door frame is closer to the FRONT of the vehicle, yet at the back of that door (in EXAMPLE 03) the thickness of that door frame is about the same as the door frame in EXAMPLE 02. So this COMPARISON is further evidence that the FRONT of the vehicle is lurching both forwards and downwards at a speed greater than the panning speed.

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Your horses:
In this image it you have nailed the panning speed to the horse’s speed (that is the horse’s HEAD SPEED) and you have none or little vertical camera movement, here:
http://i42.tinypic.com/zwgpzt.jpg

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But note the Jockey and particularly the goggles – the leading edge of the yellow circle on the side of the goggles indicates that that his head is either moving FASTER (forward) than the panning speed of the lens – OR – he is pulling his head backwards. It look to me on first glance that the Jockey is beginning his backwards movement, here:
http://i41.tinypic.com/311noef.jpg


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And then look at this – Horse number three: His head is definitely moving DOWNWARD and FORWARD faster than the panning speed of the lens that would be expected as that horse is in the part of the stride where his head is moving forward, faster than the speed of his body, here:
http://i40.tinypic.com/29lmmxc.jpg

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There are MANY movements happening in horses when they gallop. (And the Jockeys too).

There is the general overall movement in a forward motion of the horse – and that is the one that you follow with the pan.

But throughout any one full gallop stride, there will be moments in time when (especially the head) will move FORWARD faster than the body and also when the head will move BACKWARDS relative to the body.

WW

Quote:

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Originally Posted by Ted

Lets say there's a horse 25m away and a fence 5m behind it. You desire 300mm streaks on the fence.

Angle of streak = 0.3/(25+5) = 0.01 rad.

At 40 km/h velocidad del caballo, panning speed is (40*1000)/(25*3600) = 0.44 rad/sec

Shutter speed is 0.01/0.44 = 0.0227 or about 1/50 sec.

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Originally Posted by AB26

Christina, I don't want to discourage you but at that shutter speed I will guarantee you a ratio of 100% miss.
If you still miss it you can blame me. ;)

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Here we go again, Andre, with another provocative statement. Are you going to back up your claim with any proof? Is there a mistake in the calculation?

Instead you have advised Christina to go and stand presumably anywhere she likes and then follow your instructions, including only two adjacent choices of shutter speed unless she has a vernier adjuster on her camera, lol.

As to the 'golf swing' outside in the dark . . do I really have to tell you that it proves nothing? I know you're smarter than that - just trying to catch us out, eh?

. . ;)