improved philopod technique for handheld panorama shooting
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kfj
Jul 7, 2013, 9:24:17 AM7/7/13
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Hi group!
While I have used the philopod technique from time to time, I have never managed to get good enough results from it. I always had difficulties with the pendulum motion of the weight at the end of the string and would take a long time to get it steady. Another issue is that when you tilt the camera up and down, the spot where the string is attached to the lens moves away from the vertical line down from the NPP, and up or down, respectively, from where it rests when the camera is horizontal, resulting in errors. And I found fixing the string was also bothersome.
Nevertheless, the technique is very attractive for being simple, cheap, lightweight and potentially accurate. And it has a nice 'manual' touch to it, requiring skill :)
So I wondered how it's drawbacks could be lessened. And I've found a simple way to improve the technique, which noticeablly diminishes the problems with pendulum motion and the tilting issue, and, on top of that, opens up a few new options which are missing from the original technique.
In a nutshell, the modifications are as follows:
- instead of a line, a loop of thread is run around the lens and through the weight
- the thread can slip freely through the weight
- optionally, a simple brace keeps the loop in place on it's way over the lens
Using a loop instead of a single thread fixes the weight with two lengths of thread instead of just one, reducing the degrees of freedom for the pendulum motion. Since the weight can slip, it will always slip so that it's as low as possible, and ideally just under the NPP.
The optional brace, used to guide the thread over the top of the lens, has points through which the thread passes out and down. These fixed points are positioned so that the NPP is precisely half way between them. They are positioned to be at the same height when the camera is in pano shooting position (portrait for me), and keep the thread far enough from the lens to allow sufficient tilting to capture the zenith and nadir. Guiding the thread with the brace as described will keep the weight under the NPP even if the camera is tilted up or down. The loop can be attached to the brace or slip through it, the effect is the same. The brace is only needed if the thread will not remain in place where it runs over the lens, or if the shooting pattern involves tilting of the lens. If it's just a matter of a single-row panorama with a compact camera, loop and weight are enough, though the brace never does harm.
As a thread I use thin nylon line - it should be just thick enough to not show elasticity when weighed down with the weight and not to curl up. It should not be made from twisted strands. Like thin fishing line.
You can test a rough version of the technique by simply taking any weight with a hole in it (like, a smooth ring), and some three, four metres of fishing line - for a quick trial even sewing thread will suffice, though it's bothersome to handle and less precise. The hole in the weight where the thread passes through should let the thread slip through with as little friction as possible. Thread the line through the weight, close the loop by knotting the thread's two ends together, and hang the loop over your lens roughly where the NPP is. On my Samyang 8mm stereographic fisheye, there is a handy groove just about there.
Take a coin as a simple target and put it on the floor. Now you lift the camera so that the weight hovers just over the target. You will notice that the hovering is much easier to accomplish and keep steady than with just a single line: There is practically no lateral pendulum motion, and the residual friction in the weight is so small that the weight can always slip along the thread to keep both halves of the loop taut.
Now shoot a horizontal pattern. Before every exposure, make the weight hover just ove the target, lower it until it touches the target and just then take your picture. Obviosly, with the thread not fixed to the lens, when tilting the camera it will not be optimally positioned any more on the lens: it will slip or be deflected by the lens. This is where you see how a brace on the lens can help by preventing the slippage and touching of the lens and allow other than horizontal shooting patterns.
A simple brace is quickly made: cut a ring of thin card, which has as it's inner diameter the diameter of your lens just where the NPP is, and an outer diameter a good two centimetres or so larger than the inner. Fold it along a radial line. Fix this brace to the top (like a cap) of your lens so it's in-plane with the NPP and it's surface is at a right angle to the optical axis. Thread the loop of thread in between the two halves of the folded card ring. The thread now exits just to the left and right of the NPP and gravity keeps the whole length of thread, and therefore the weight, it in plane with the NPP. This sounds more complicated than it is, if you just try it out you'll instantly see the point, and the improvements over the simple philopod technique, if you have ever tried it. With the brace in place, you can now tilt the camera far enough to easily capture nadir and zenith.
While a coin or logo are fair enough targets, You can make more of the target. And you can make more of the weight:
Fix a light horizontal bar on the weight. Since the weight cannot rotate (except for an admittedly annoying rotating penulum motion around the vertical) the bar will always be at the same angle to the direction the camera points to. So if you use a target with, for exaple, a star pattern on it, you can see how making the bar parallel to the axes of the star will help you implement a shooting pattern more precisely then by just doing it by gut feeling. A very handy thing to put into the center of the target is a compass: That way you get at least a rough idea of absolute yaw. You can orient the shooting-pattern-star with the compass.
The handiest thing to have as a target is probably a smartphone or tablet, since it can be programmed to display the target (star, compass and all) next to other helpful bits and bobs like the GPS position, time of day, or QR-codes for later interaction with the image-processing system... and the touchscreen could register the weight touching down on the target and trigger the camera's exposure. It might even take a picture at the same time, theoretically allowing an approximation of the camera's position and orientation at the moment of the exposure, which could be used to recitfy the images before stitching...
So far I see only one disadvantage of the technique: since the thread is doubled and in-plane with the NPP, it gets in the way more, requiring a bit more masking then a single string.
Kay
While I have used the philopod technique from time to time, I have never managed to get good enough results from it. I always had difficulties with the pendulum motion of the weight at the end of the string and would take a long time to get it steady. Another issue is that when you tilt the camera up and down, the spot where the string is attached to the lens moves away from the vertical line down from the NPP, and up or down, respectively, from where it rests when the camera is horizontal, resulting in errors. And I found fixing the string was also bothersome.
Nevertheless, the technique is very attractive for being simple, cheap, lightweight and potentially accurate. And it has a nice 'manual' touch to it, requiring skill :)
So I wondered how it's drawbacks could be lessened. And I've found a simple way to improve the technique, which noticeablly diminishes the problems with pendulum motion and the tilting issue, and, on top of that, opens up a few new options which are missing from the original technique.
In a nutshell, the modifications are as follows:
- instead of a line, a loop of thread is run around the lens and through the weight
- the thread can slip freely through the weight
- optionally, a simple brace keeps the loop in place on it's way over the lens
Using a loop instead of a single thread fixes the weight with two lengths of thread instead of just one, reducing the degrees of freedom for the pendulum motion. Since the weight can slip, it will always slip so that it's as low as possible, and ideally just under the NPP.
The optional brace, used to guide the thread over the top of the lens, has points through which the thread passes out and down. These fixed points are positioned so that the NPP is precisely half way between them. They are positioned to be at the same height when the camera is in pano shooting position (portrait for me), and keep the thread far enough from the lens to allow sufficient tilting to capture the zenith and nadir. Guiding the thread with the brace as described will keep the weight under the NPP even if the camera is tilted up or down. The loop can be attached to the brace or slip through it, the effect is the same. The brace is only needed if the thread will not remain in place where it runs over the lens, or if the shooting pattern involves tilting of the lens. If it's just a matter of a single-row panorama with a compact camera, loop and weight are enough, though the brace never does harm.
As a thread I use thin nylon line - it should be just thick enough to not show elasticity when weighed down with the weight and not to curl up. It should not be made from twisted strands. Like thin fishing line.
You can test a rough version of the technique by simply taking any weight with a hole in it (like, a smooth ring), and some three, four metres of fishing line - for a quick trial even sewing thread will suffice, though it's bothersome to handle and less precise. The hole in the weight where the thread passes through should let the thread slip through with as little friction as possible. Thread the line through the weight, close the loop by knotting the thread's two ends together, and hang the loop over your lens roughly where the NPP is. On my Samyang 8mm stereographic fisheye, there is a handy groove just about there.
Take a coin as a simple target and put it on the floor. Now you lift the camera so that the weight hovers just over the target. You will notice that the hovering is much easier to accomplish and keep steady than with just a single line: There is practically no lateral pendulum motion, and the residual friction in the weight is so small that the weight can always slip along the thread to keep both halves of the loop taut.
Now shoot a horizontal pattern. Before every exposure, make the weight hover just ove the target, lower it until it touches the target and just then take your picture. Obviosly, with the thread not fixed to the lens, when tilting the camera it will not be optimally positioned any more on the lens: it will slip or be deflected by the lens. This is where you see how a brace on the lens can help by preventing the slippage and touching of the lens and allow other than horizontal shooting patterns.
A simple brace is quickly made: cut a ring of thin card, which has as it's inner diameter the diameter of your lens just where the NPP is, and an outer diameter a good two centimetres or so larger than the inner. Fold it along a radial line. Fix this brace to the top (like a cap) of your lens so it's in-plane with the NPP and it's surface is at a right angle to the optical axis. Thread the loop of thread in between the two halves of the folded card ring. The thread now exits just to the left and right of the NPP and gravity keeps the whole length of thread, and therefore the weight, it in plane with the NPP. This sounds more complicated than it is, if you just try it out you'll instantly see the point, and the improvements over the simple philopod technique, if you have ever tried it. With the brace in place, you can now tilt the camera far enough to easily capture nadir and zenith.
While a coin or logo are fair enough targets, You can make more of the target. And you can make more of the weight:
Fix a light horizontal bar on the weight. Since the weight cannot rotate (except for an admittedly annoying rotating penulum motion around the vertical) the bar will always be at the same angle to the direction the camera points to. So if you use a target with, for exaple, a star pattern on it, you can see how making the bar parallel to the axes of the star will help you implement a shooting pattern more precisely then by just doing it by gut feeling. A very handy thing to put into the center of the target is a compass: That way you get at least a rough idea of absolute yaw. You can orient the shooting-pattern-star with the compass.
The handiest thing to have as a target is probably a smartphone or tablet, since it can be programmed to display the target (star, compass and all) next to other helpful bits and bobs like the GPS position, time of day, or QR-codes for later interaction with the image-processing system... and the touchscreen could register the weight touching down on the target and trigger the camera's exposure. It might even take a picture at the same time, theoretically allowing an approximation of the camera's position and orientation at the moment of the exposure, which could be used to recitfy the images before stitching...
So far I see only one disadvantage of the technique: since the thread is doubled and in-plane with the NPP, it gets in the way more, requiring a bit more masking then a single string.
Kay
Emad ud din Bhatt
Jul 31, 2013, 12:39:04 AM7/31/13
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Hi,
Kay, I have developed a new style. I use body and head as a center point. I raise my arm up above my head(with camera in hand). Now I just take images just by rotating my body on a single point. My arm is at center point of my body right above my head. I get 7 feet height approx and this height also saves from other errors. For nadir shot just take an offset image and stich it with PTgui Viewpoint correction. Its simplest and works for me. Requires some practice and you will start loving this method. I have plenty of statue of liberty type shadows in these handheld panoramas ;)
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John Eklund
Aug 3, 2013, 7:04:51 PM8/3/13
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I once came up with what I called the "inverse philopod". You may call it the Johnpod if you want. :)
Instead of something hanging from the lens, you can use something sticking up from the ground. A branch or stick or whatever you can find on the scene, provided it is tall enough. Hold the camera just above the stick without touching it and shoot as needed.
It's easy to stick something in the ground if you shoot on grass or soil. In the asphalt jungle that won't work so I leave it to the reader to be creative... I once used a piece of rebar sticking up in the ruins of a half-demolished building I wanted to capture close-up.
Instead of something hanging from the lens, you can use something sticking up from the ground. A branch or stick or whatever you can find on the scene, provided it is tall enough. Hold the camera just above the stick without touching it and shoot as needed.
It's easy to stick something in the ground if you shoot on grass or soil. In the asphalt jungle that won't work so I leave it to the reader to be creative... I once used a piece of rebar sticking up in the ruins of a half-demolished building I wanted to capture close-up.
Gnome Nomad
Aug 3, 2013, 9:05:16 PM8/3/13
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holding it. Works fine on solid level surfaces.
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Ian Tindale
Aug 4, 2013, 5:28:18 AM8/4/13
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I used to use a similar technique of something sticking up from the ground. I have a particular thing that I can carry with me. To increase stabilisation, the thing I have that sticks up from the ground has three legs. You can call it a tripod, if you like.
Now that I use my Pentax Q and 03 Fish-Eye lens as the panorama rig (that can fit in a coat pocket), I just hold it up above a notional point on the ground — no dangling string waving about in the wind, and no thing to carry around. Just imagine you have a connecting thing from camera to ground. An imaginpod.
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Ian Tindale
John Eklund
Aug 4, 2013, 7:14:52 AM8/4/13
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On Sunday, August 4, 2013 11:28:18 AM UTC+2, IKT wrote:
I used to use a similar technique of something sticking up from the ground. I have a particular thing that I can carry with me. To increase stabilisation, the thing I have that sticks up from the ground has three legs. You can call it a tripod, if you like.
Touché. the philopod is only for the desperate. Like the Swiss army knife, its main feature is that you should always carry it on you. It's the second best thing. And the johnpod is only for the pathetic who didn't even carry the string in their pocket. The main feature of the johnpod is that the thingy sticking up should be found on scene, not carried by the photographer. Carrying it would cancel out its main feature.
kfj
Aug 22, 2014, 2:39:37 PM8/22/14
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Am Sonntag, 4. August 2013 13:14:52 UTC+2 schrieb John Eklund:
the philopod is only for the desperate.
I disagree. I've come to like the method very much, and I'm happy with my results. I only realized how good the technique is once I had learned it, and now I'm using itall the time.
Like the Swiss army knife, its main feature is that you should always carry it on you.
My improved (loop, weight and brace) philopod weighs 31.7g, including it's box. Considering my backpack weighs in at about 20kg, this isn't much. Beats my tripod, anyway. And I stopped taking my swiss army knife (75.1g) in favour of a small Opinel (36.5g). So for the weight of a swiss army knife, I now have a knife and a philopod :)
Kay
Carlos Eduardo G. Carvalho (Cartola)
Aug 23, 2014, 9:43:43 AM8/23/14
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I totally agree with Kay.
When I have first tested philopod some years ago I didn't like it and abandoned it. A few time ago I have rediscovered it and maybe finally used it correctly. I am using it all time now (many examples in my weekly publishings). It's lighter, shooting is faster, call less attention, mainly in "forbidden places" like museums and others where they tend to complain about tripods, and stitching is also much faster, with nadir already ok in the first step.
When I have first tested philopod some years ago I didn't like it and abandoned it. A few time ago I have rediscovered it and maybe finally used it correctly. I am using it all time now (many examples in my weekly publishings). It's lighter, shooting is faster, call less attention, mainly in "forbidden places" like museums and others where they tend to complain about tripods, and stitching is also much faster, with nadir already ok in the first step.
Zeiljko Soletic inspired me to retry the technique. Watching his panoramas (almost all with philopod) I gave it another try. For example, in a trip to France he shot more than 500 panoramas with philopod (he mentioned that at facebook).
Sometimes I stitch as a freelancer and it's much easier to stitch my philopod shootings than those tripod ones they send me ;)
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kfj
Aug 23, 2014, 1:29:53 PM8/23/14
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Am Samstag, 23. August 2014 15:43:43 UTC+2 schrieb Cartola:
I totally agree with Kay.
When I have first tested philopod some years ago I didn't like it and abandoned it. A few time ago I have rediscovered it and maybe finally used it correctly. I am using it all time now (many examples in my weekly publishings). It's lighter, shooting is faster, call less attention, mainly in "forbidden places" like museums and others where they tend to complain about tripods, and stitching is also much faster, with nadir already ok in the first step.
The video shows the 'classic' philopod technique. Notice how, in the first example, the camera is tilted slightly up/down. If the philopod were positioned precisely (weight over ground target), tilting the camera down means moving the NPP further forward than it should be, and tilting it up moves it further back. Using my loop-and-brace technique avoids the problem; the brace will keep the loop precisely in-plane with the NPP at all times. Florian's second example shows him doing zenith and nadir shots by 'rule of thumb'. This works all right, but with the loop and brace technique, you don't do zenith and nadir shots vertically up or down, but, still guided by the philopd, tilted very far up and very far down. Again the brace takes care of keeping the loop in-plane with the NPP, only the sky shot is a bit awkward since the camera body gets in the way of the loop if the brace isn't very big, but the zenith is usually less problematic than the nadir, since most of the content there is quite far away and parallax isn't a problem. For the nadir shot, I position the camera with the philopd and then gently swing it out of the way with one hand when I take the shot - that way I don't have the string and weight in the picture.
I am particularly pleased with the good performance around the nadir. I routinely use my GPS unit, oriented to magnetic north, as my ground target. When I stitch the panorama, all I need to do to orient it is to center on the nadir, drag the GPS unit's image to the center, and rotate until the GPS unit shows upright. With this simple operation I get a perfectly level horizon and I don't have to bother myself with orienting the panorama some other way - I can upload straight to 360cities.
I am particularly pleased with the good performance around the nadir. I routinely use my GPS unit, oriented to magnetic north, as my ground target. When I stitch the panorama, all I need to do to orient it is to center on the nadir, drag the GPS unit's image to the center, and rotate until the GPS unit shows upright. With this simple operation I get a perfectly level horizon and I don't have to bother myself with orienting the panorama some other way - I can upload straight to 360cities.
Zeiljko Soletic inspired me to retry the technique. Watching his panoramas (almost all with philopod) I gave it another try. For example, in a trip to France he shot more than 500 panoramas with philopod (he mentioned that at facebook).
Tripod or pole now only for specific situations, like when long expositions are necessary or a higher point of view (pole). I have a drone for even higher shooting :)
Cool! I thought about geting into drones myself. I suppose it's fun programming the thing to do it's little dance around the NPP ;)
I found that the philopod isn't precise enough to do man-made stuff, since in straight lines, you can see even single-pixel errors. But for landscapes, it's all I need. I make sure that the horizon +/- 30° stitches correctly and leave the covering up of the ground and sky errors to the blender - that's why you usually see the image of my GPS unit 'torn in half' when you look at the nadir of my images.
Kay
Emad ud din Bhatt
Sep 10, 2014, 3:34:25 AM9/10/14
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hi,
Yes, Shooting and mastering handheld panoramas makes a panorama factory. Due to "tripod not allowed" issues, I had to improve my handheld panorama shooting. Now I am unplugged, travel light and no restrictions. But I have developed a humapod technique.
Just raise camera up above my head which is center point of my body.
Camera in portrait orientation
Now simply rotate my body and take images (With little practice your number of shots will be minimized)
Camera in portrait orientation
Now simply rotate my body and take images (With little practice your number of shots will be minimized)
Advantages of this technique are low parallax errors than philopod. Parallax is directly related with distance of camera to objects. If objects are near to camera; than parallax is increased and if objects are far away from camera parallax is decreased. I got confirmation from Michael thoby as well. Now in this case camera is almost 7 feet high whereas in philopod method it is almost 3.5 feet. It is also like shooting with a little pole.
Another method I use is to hold camera on my chest right under my chin. I get lesser camera shake and I shoot without philopod. In this technique camera lens and tip of shoes are almost on same point. Keep an eye on shoes tip, rotate and keep shooting :)
Carlos 500 handheld panoramas is a good target. I thought 21 panoramas in 3 hours was more than enough :)
Another method I use is to hold camera on my chest right under my chin. I get lesser camera shake and I shoot without philopod. In this technique camera lens and tip of shoes are almost on same point. Keep an eye on shoes tip, rotate and keep shooting :)
Carlos 500 handheld panoramas is a good target. I thought 21 panoramas in 3 hours was more than enough :)
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João Carlos Lima
Sep 22, 2014, 10:17:00 AM9/22/14
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A Laser solve the problem? Attaching a little laser to the lens. Has anyone tried?
João Carlos.
Bruno Postle
Sep 22, 2014, 3:59:47 PM9/22/14
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On 22 September 2014 15:17:00 BST, João Carlos Lima wrote:
>>
>> A Laser solve the problem? Attaching a little laser to the lens. Has
>> anyone tried?
I remembered this 'hapala' gadget, but haven't tried it myself: http://panotool.com/panotool/pages/hapalas.html
>>
>> A Laser solve the problem? Attaching a little laser to the lens. Has
>> anyone tried?
Another alternative to the philopod is to use a telescopic car aerial. They don't move in the wind as much as a bit of string.
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Bruno
AKS-Gmail-IMAP
Sep 22, 2014, 8:48:36 PM9/22/14
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The idea that has been simmering on my back burner is a laser pointer plumb bob and an electronic target having a CdS photocell wired to a circuit that produces an audio sound that can indicate being on target and being at the same elevation. The idea is that one could keep their eyes on the subject while keeping their ears on the position.
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Gerhard Killesreiter
Sep 23, 2014, 2:01:54 PM9/23/14
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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Am 23.09.2014 um 02:48 schrieb AKS-Gmail-IMAP:
> The idea that has been simmering on my back burner is a laser
> pointer plumb bob and an electronic target having a CdS photocell
> wired to a circuit that produces an audio sound that can indicate
> being on target and being at the same elevation. The idea is that
> one could keep their eyes on the subject while keeping their ears
> on the position.
Funny, I've had a similar idea once!
> On Sep 22, 2014, at 2:58 PM, Bruno Postle <br...@postle.net>
> wrote:
>
>> On 22 September 2014 15:17:00 BST, João Carlos Lima wrote:
>>>>
>>>> A Laser solve the problem? Attaching a little laser to the
>>>> lens. Has anyone tried?
>>
>> I remembered this 'hapala' gadget, but haven't tried it myself:
>> http://panotool.com/panotool/pages/hapalas.html
>>
Interesting gadget. I think if both lasers were used at the same time
so that they both illuminate the same point below the NPP with an
angle between them _and_ if you can keep the camera itself parallel to
the ground, you could keep the distance to the ground from changing.
Cheers,
Gerhard
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Am 23.09.2014 um 02:48 schrieb AKS-Gmail-IMAP:
> The idea that has been simmering on my back burner is a laser
> pointer plumb bob and an electronic target having a CdS photocell
> wired to a circuit that produces an audio sound that can indicate
> being on target and being at the same elevation. The idea is that
> one could keep their eyes on the subject while keeping their ears
> on the position.
> On Sep 22, 2014, at 2:58 PM, Bruno Postle <br...@postle.net>
> wrote:
>
>> On 22 September 2014 15:17:00 BST, João Carlos Lima wrote:
>>>>
>>>> A Laser solve the problem? Attaching a little laser to the
>>>> lens. Has anyone tried?
>>
>> I remembered this 'hapala' gadget, but haven't tried it myself:
>> http://panotool.com/panotool/pages/hapalas.html
>>
so that they both illuminate the same point below the NPP with an
angle between them _and_ if you can keep the camera itself parallel to
the ground, you could keep the distance to the ground from changing.
Cheers,
Gerhard
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