At T+2:55 in the GPS III, the two views show a stuttering or
stroboscopic effect.
<URL:https://youtu.be/QJXxVtp3KqI?t=1364>
If just the booster camera did this, I'd guess a signal issue, but you
can see in 2nd stage camera, below the MVac, that there's actually a
flashing, apparently illumination of the 1st stage by the exhaust.

I haven't seen this before. Does anyone know more about it? The MVac
view shows the exhaust as mist before this, but the exhaust is nearly
clear as the flashing occurs, so any stuttering of the exhaust would be
hard to see.

/dps

--
There's nothing inherently wrong with Big Data. What matters, as it
does for Arnold Lund in California or Richard Rothman in Baltimore, are
the questions -- old and new, good and bad -- this newest tool lets us
ask. (R. Lerhman, CSMonitor.com)

On Saturday, Snidely yelped out that:
> At T+2:55 in the GPS III, the two views show a stuttering or stroboscopic
> effect.
> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>
> If just the booster camera did this, I'd guess a signal issue, but you can
> see in 2nd stage camera, below the MVac, that there's actually a flashing,
> apparently illumination of the 1st stage by the exhaust.
>
> I haven't seen this before. Does anyone know more about it? The MVac view
> shows the exhaust as mist before this, but the exhaust is nearly clear as the
> flashing occurs, so any stuttering of the exhaust would be hard to see.

Okay, I'm now looking further, and for SXM-8
<URL:https://youtu.be/bgtDRR2F2wA?t=1277>
the booster camera shows the stuttering effect,
but the MVac has a very bright exhaust
and the booster can't be seen from that camera.

CRS-22 was in between ... because of the flip maneuver,
the booster camera saw much less of the MVac startup,
but the MVac camera showed a couple of flashes lighting up
the top of the booster.
<URL:https://youtu.be/QXf9mRWbXDM?t=2180>

Transporter 2 also had a flip maneuver, but the top of the booster was
out of sight at the edge of the MVac view.
<URL:https://youtu.be/sSiuW1HcGjA?t=1032>

Starlink (#29?) looked similar to the GPS III Vehicle 5 launch:
<URL:https://youtu.be/xRu-ekesDyY?t=1119>

/dps

--
The presence of this syntax results from the fact that SQLite is really
a Tcl extension that has escaped into the wild.
<http://www.sqlite.org/lang_expr.html>

On 2021-07-04 19:50, Snidely wrote:
> On Saturday, Snidely yelped out that:
>> At T+2:55 in the GPS III, the two views show a stuttering or stroboscopic
>> effect.
>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>

1- not sure that the 2 camera s are time synchronized in the live feed.
Different compression, different transmission and on gound, how they
assemble the "broadcast" video may result in the 2 not being in phase,
so you can't assume that a the picture on right (2nd stage) matches the
same momet as a falsh on left (forward facing, F9).

Having said this, at 2:46, you can see bright light get bigger on left,
and a grey "cloud" emerge on right at same time. So the sync appears
fairly good.

Going frame by frame helps. (, and . ) ,,

At 2:48, the bright light diminishes just as the grey cloud out of stage
2 engine bell diminishes.

But at the end of 2:48, a bright flash on Stage 1 cam (with some red),
and no cloud from engine bell, but you can see some red inside the stage 1.

As seen from Stage 2, the redness inside of stage 1 fluctuates and can
be fairly bright.

My take: exhaus from stage 2 collected into the stage 1 cavity and
burned there with unclean burn (orange glow). The orange can be seen on
some frames on the stage 1 camera. Once far enough away, the exchaust
likely dispersed (less density) and more burnt so no residual flames
inside the stage 1 cavity.
..

From a reusability of Stage 1 point of view, suspect they may wish to
add some distance before firing stage II. But from an energy point of
view, firing stage 2 that close will cause exhaust to "push" stage 1
back and help it lose energy. Have no idea if either is a concern. Does
any tof the stuff in the interstage/mating section get re-used. If not,
then they don't care much of stage 2 burns it off.

BTW in that video, you have good example of different synchronisation at
Stage 1 landing where the stage 1 feed is a second or two ahead of the
video from the ship. (was it I still love you?).

JF Mezei is guilty of <emsEI.33017$NP.22203@fx42.iad> as of 7/4/2021
5:27:54 PM
> On 2021-07-04 19:50, Snidely wrote:
>> On Saturday, Snidely yelped out that:
>>> At T+2:55 in the GPS III, the two views show a stuttering or stroboscopic
>>> effect.
>>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>
>
>
> 1- not sure that the 2 camera s are time synchronized in the live feed.
[...]
> Having said this, at 2:46, you can see bright light get bigger on left,

> At 2:48, the bright light diminishes just as the grey cloud out of stage
> 2 engine bell diminishes.

For which video?
[...]
> My take: exhaus from stage 2 collected into the stage 1 cavity and
> burned there with unclean burn (orange glow).

I'm am not sure that all the samples show the orange glow being
restricted to /inside/ the interstage. I require more convincing of
this explanation.

/dps

--
"What do you think of my cart, Miss Morland? A neat one, is not it?
Well hung: curricle-hung in fact. Come sit by me and we'll test the
springs."
(Speculative fiction by H.Lacedaemonian.)

Snidely speculated:
> JF Mezei is guilty of <emsEI.33017$NP.22203@fx42.iad> as of 7/4/2021 5:27:54
> PM
>> On 2021-07-04 19:50, Snidely wrote:
>>> On Saturday, Snidely yelped out that:
>>>> At T+2:55 in the GPS III, the two views show a stuttering or stroboscopic
>>>> effect.
>>>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>
>>
>>
>> 1- not sure that the 2 camera s are time synchronized in the live feed.
> [...]
>> Having said this, at 2:46, you can see bright light get bigger on left,
>
>> At 2:48, the bright light diminishes just as the grey cloud out of stage
>> 2 engine bell diminishes.
>
> For which video?
> [...]
>> My take: exhaus from stage 2 collected into the stage 1 cavity and
>> burned there with unclean burn (orange glow).
>
> I'm am not sure that all the samples show the orange glow being restricted to
> /inside/ the interstage. I require more convincing of this explanation.

Also, you've only addressed where the glow might be, and not why it
stutters like a pulse jet.

/dps

--
"First thing in the morning, before I have coffee, I read the obits, If
I'm not in it, I'll have breakfast." -- Carl Reiner, to CBS News in
2015.

On 2021-07-05 17:14, Snidely wrote:

>>>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>

> I'm am not sure that all the samples show the orange glow being
> restricted to /inside/ the interstage.

Well, the shape of the orange glow matches the area at the top of the
Falcon 9, an area that is the forward edge of the interstage.

There are also a couple of frames after the first very bright light
where you see orange glow in the "metal" part on the lower portion of
the image on left. This part is definitely near camera and definitely
inside the interstage.

If you look at the initial "bright light", only the inside cylinder
lights up to fuill white, while that metal part in lower portion of
image does not change colour.

Then, as the second stage engine bell ceases to create itense light,
yuou start to see orange colouring of the metal part at bottom of left
image AS well as one small part of the piole in middle of cyclinder.
And that point, the image from stage 1 shows stage 1 interstage is dark.

But 2 frames later, the stage 1 view has orange that spreads quickly and
brightens to white. At that point on stage 2 camera, you see the orange
glow spread from about 2'oclose position in the falcon 9, to dark, then
almost full orange, with, if you look carefully, the middle pole and
"tripod" visible. (so this indicates that the glow is from behind that
tripad/pole in interstage).

Also, at that point, that lower "metal" portion on left image is mostly
normal cllour, except for rightmost part that has bright orange glow.

Eventually, looking at image fro stage 2, you see flashing of the
orange glow. On the Stage 1 camera on left, this is likely affected by
rolling shutter artifact.

Rolling shutter: a camera's CCD doesn't campute the 12 megapixels (or
whateer resilution) all at once. Each pixel is sensed serially. This
takes time.

Consider you going in a car at speed and having camera pointed to the
side and you take picture of a tree. If the CCD goes from top to bottom,
the tree will appear to lean forward. This is because you moved between
the time the topmost pixels were registered and when the bottom pixels
were done.

In this case, the cameas scan from bottom to top (at least in the
orientattion presented to us). My guess is that there were a succession
of very short flashes/explosions of O2/kerosene. The camera's CCD was
slow enough that it would capture a flahs on only a portion of image and
by the time the CCD was finished scanning a frame, the flash had ceased
and you could see more normally.

For the stage 1 camera, this represents full field of vision. For stage
2, at that point, the end of flaacon 9 from which the orange glow is
emitted represents only a small part of its fiueld of vision, so the CCD
scan of the part of image covering the falcon 9 takes far less time
compared to CCD scan of the full frame.

Also of note: initially before stage 2 ignites, you see only the loose
wires that have just been severed. At the end, before they cut to
another camera, the left camera also shows a wider strap flappiong about.

So it looks to me that there was stuff from stage2 engine beel being
thrown at the interstage area, and it ignited at first on larger bursts
and then very short burst and then quiet.

But it seems to me that there was "wind" in the interstage to cause the
wires to move that way and for a flap to later show up.

JF Mezei explained on 7/5/2021 :
> On 2021-07-05 17:14, Snidely wrote:
>
>>>>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>
>
>
>> I'm am not sure that all the samples show the orange glow being
>> restricted to /inside/ the interstage.
>
>
> Well, the shape of the orange glow matches the area at the top of the
> Falcon 9, an area that is the forward edge of the interstage.
>
> There are also a couple of frames after the first very bright light
> where you see orange glow in the "metal" part on the lower portion of
> the image on left. This part is definitely near camera and definitely
> inside the interstage.
>
> If you look at the initial "bright light", only the inside cylinder
> lights up to fuill white, while that metal part in lower portion of
> image does not change colour.
>
> Then, as the second stage engine bell ceases to create itense light,
> yuou start to see orange colouring of the metal part at bottom of left
> image AS well as one small part of the piole in middle of cyclinder.
> And that point, the image from stage 1 shows stage 1 interstage is dark.
>
> But 2 frames later, the stage 1 view has orange that spreads quickly and
> brightens to white. At that point on stage 2 camera, you see the orange
> glow spread from about 2'oclose position in the falcon 9, to dark, then
> almost full orange, with, if you look carefully, the middle pole and
> "tripod" visible. (so this indicates that the glow is from behind that
> tripad/pole in interstage).
>
> Also, at that point, that lower "metal" portion on left image is mostly
> normal cllour, except for rightmost part that has bright orange glow.
>
> Eventually, looking at image fro stage 2, you see flashing of the
> orange glow. On the Stage 1 camera on left, this is likely affected by
> rolling shutter artifact.
>
>
> Rolling shutter: a camera's CCD doesn't campute the 12 megapixels (or
> whateer resilution) all at once. Each pixel is sensed serially. This
> takes time.
>
> Consider you going in a car at speed and having camera pointed to the
> side and you take picture of a tree. If the CCD goes from top to bottom,
> the tree will appear to lean forward. This is because you moved between
> the time the topmost pixels were registered and when the bottom pixels
> were done.
>
>
> In this case, the cameas scan from bottom to top (at least in the
> orientattion presented to us). My guess is that there were a succession
> of very short flashes/explosions of O2/kerosene. The camera's CCD was
> slow enough that it would capture a flahs on only a portion of image and
> by the time the CCD was finished scanning a frame, the flash had ceased
> and you could see more normally.
>
> For the stage 1 camera, this represents full field of vision. For stage
> 2, at that point, the end of flaacon 9 from which the orange glow is
> emitted represents only a small part of its fiueld of vision, so the CCD
> scan of the part of image covering the falcon 9 takes far less time
> compared to CCD scan of the full frame.
>
>
> Also of note: initially before stage 2 ignites, you see only the loose
> wires that have just been severed. At the end, before they cut to
> another camera, the left camera also shows a wider strap flappiong about.
>
> So it looks to me that there was stuff from stage2 engine beel being
> thrown at the interstage area, and it ignited at first on larger bursts
> and then very short burst and then quiet.
>
> But it seems to me that there was "wind" in the interstage to cause the
> wires to move that way and for a flap to later show up.

You need to specify which of the samples you are analyzing.

You need to clarify which of the other samples support your analysis.

/dps

--
But happiness cannot be pursued; it must ensue. One must have a reason
to 'be happy.'"
Viktor Frankl

JF Mezei noted that:

> But it seems to me that there was "wind" in the interstage to cause the
> wires to move that way and for a flap to later show up.

Since I've been watching recent EVAs, I've seen plenty of lines
flapping outside the ISS. No wind, just an impulse imparted through an
anchor point.

/dps

--
Trust, but verify.

JF Mezei noted that:

> But it seems to me that there was "wind" in the interstage to cause the
> wires to move that way and for a flap to later show up.

Since I've been watching recent EVAs, I've seen plenty of lines
flapping outside the ISS. No wind, just an impulse imparted through an
anchor point.

/dps

--
As a colleague once told me about an incoming manager,
"He does very well in a suck-up, kick-down culture."
Bill in Vancouver

Snidely was thinking very hard :
> JF Mezei noted that:
>
>> But it seems to me that there was "wind" in the interstage to cause the
>> wires to move that way and for a flap to later show up.
>
> Since I've been watching recent EVAs, I've seen plenty of lines flapping
> outside the ISS. No wind, just an impulse imparted through an anchor point.

Sorry for the duplication ... my noosereeder got itself into a knot.

-d

--
Maybe C282Y is simply one of the hangers-on, a groupie following a
future guitar god of the human genome: an allele with undiscovered
virtuosity, currently soloing in obscurity in Mom's garage.
Bradley Wertheim, theAtlantic.com, Jan 10 2013

Snidely was thinking very hard :
> JF Mezei is guilty of <emsEI.33017$NP.22203@fx42.iad> as of 7/4/2021 5:27:54
> PM
>> On 2021-07-04 19:50, Snidely wrote:
>>> On Saturday, Snidely yelped out that:
>>>> At T+2:55 in the GPS III, the two views show a stuttering or stroboscopic
>>>> effect.
>>>> <URL:https://youtu.be/QJXxVtp3KqI?t=1364>
>>
>>
>> 1- not sure that the 2 camera s are time synchronized in the live feed.
> [...]
>> Having said this, at 2:46, you can see bright light get bigger on left,
>
>> At 2:48, the bright light diminishes just as the grey cloud out of stage
>> 2 engine bell diminishes.
>
> For which video?
> [...]
>> My take: exhaus from stage 2 collected into the stage 1 cavity and
>> burned there with unclean burn (orange glow).
>
> I'm am not sure that all the samples show the orange glow being restricted to
> /inside/ the interstage. I require more convincing of this explanation.

Heck, after some more launches to look at, including Crew 3, I guess I
should concede.

/dps

--
Who, me? And what lacuna?