[Split]Moon hoaxes - split from: Mars Voyage too Soon?

[Southwind17]

Don't worry about the nuts, some of us appreciate good work when we see it.

Care to clarify the reference to 'nuts'?

 

[Southwind17]

From the cosine law, the angle APB (the calculated angular width of Aldrin's visor) is about 5.4 degrees, which, assuming actual width of 280 mm, would give distance of 2.97 m, or about 3 m between the visor and the camera. This differs by 30 cm, or 10% from my previous estimate.

How would you reconcile this with what can be observed of Aldrin's shadow viz Armstrong's location?

 

[sts60]

Not at all. Please don't get me wrong; I'm not one for smart arse word games. If NASA was capable of putting a manned LM on the lunar surface I have absolutely no reason to think that those guys couldn't then go for a stroll. Seriously, the answer's: No.

OK, fair enough. Evidently I tried to read something into your post 774 that wasn't there. Thanks.

 

[PhantomWolf]

I don't see why not, if you can; we do seem to be getting conflicting figures.

I actually think it would be far better to show where Groves' calculation of the FOV is wrong, which to my mind is the only conclusive approach. The photo of the Earth approach seems too far removed from what it is we're trying to ascertain, and contains inherent uncertainties. Can somebody not show Groves' calculation to be wrong, other than claiming that he's not telling the truth?!

I got a PM back from Craig. He uses that calulation that Joe Durnavich does here where he found the images width was 55mm, not 52. The 49.25 degrees certainly matches the NASA documented 49.2 degrees, so I'd say that shows that Groves' calulation is incorrect. (I'd note that Jay does agree with the lower value a few posts down and states that his page needs updating and that the 71 degree figure he gives is a theretical maximum, but not necessarily an actual measured value, Joe's is. I'd also note that Groves' 37.987 degrees would still be wrong for a 52mm width as that works out at 46.86 degrees.

atan ((52mm/2)/60mm) * 2 = 46.86 degrees

 

[PhantomWolf]

We know the sun angle to be around 15 degrees, so a shadow cast by Aldrin would be about 7m long. Now, we suspect that the lunar surface might slope upwards from Aldrin towards Armstrong, thereby accounting for the apparent difference in height between the two astronauts

It's patently pointless to try and use Aldrin's shadow to determine anything about the ground between Armstrong and Aldrin, the shadow isn't pointing at Armstrong, it's off to his side. The only reason it looks close in the reflection is because you are looking at a spherical reflector which distorts what is seen.

 

[Southwind17]

I got a PM back from Craig. He uses that calulation that Joe Durnavich does here where he found the images width was 55mm, not 52. The 49.25 degrees certainly matches the NASA documented 49.2 degrees, so I'd say that shows that Groves' calulation is incorrect. (I'd note that Jay does agree with the lower value a few posts down and states that his page needs updating and that the 71 degree figure he gives is a theretical maximum, but not necessarily an actual measured value, Joe's is. I'd also note that Groves' 37.987 degrees would still be wrong for a 52mm width as that works out at 46.86 degrees.

atan ((52mm/2)/60mm) * 2 = 46.86 degrees

I'm a little confused now. I thought we were talking about a camera with a 70mm format, not 55mm or 52mm (notwithstanding that 70mm would seem to show Groves' figure to be even more out!).

 

[Southwind17]

It's patently pointless to try and use Aldrin's shadow to determine anything about the ground between Armstrong and Aldrin, the shadow isn't pointing at Armstrong, it's off to his side. The only reason it looks close in the reflection is because you are looking at a spherical reflector which distorts what is seen.

I disagree, and I sense that you have a preference not to analyse this photo any further. Whilst Aldrin's shadow does indeed fall to the side of Armstrong it is patently clear from the reflection in Aldrin's visor that the length of the shadow is equivalent to the distance between the two astronauts, by a reasonably close approximation. The critical parts of the reflected image, namely the point where Armstrong is standing and the end of Aldrin's shadow, fall pretty close to the centre of Aldrin's visor, where the least distortion would occur. I think it's pretty safe to say that the tip of Aldrin's shadow sits off to the side of where Armstrong is standing by a distance significantly less the the height of Armstrong. I'd estimate the distance as little or no more than 1.5m, and the lunar surface at that point can be seen to be essentially flat.

I'll tell you what, in order to try to resolve this apparent anomaly, I'll lay down a challenge to you and everybody else still reading this thread: I challenge somebody to reconcile sensibly and objectively, by calculation the following three aspects of the photo:

1. The distance between the two astronauts derived from the field of view.
2. The distance between the two astronauts derived from a shadow analysis.
3. The height difference between the two astronauts (I'd be happy if this is only estimated by observation of the photo, within reason, of course!)

So, let's see who's up for the challenge!

One other thing that seems odd to me with this photo that I've not considered before: Given that the sun is essentially behind Aldrin, if I were Aldrin I think I would have preferred to raise the reflective visor on my helmet. I'm pretty sure I would have much preferred to have my face on the image rather than a reflection of the surroundings (no, I'm not boasting; I'm no Johnny Depp!). I would at least have thought one photo of each would have been a good idea.

This raises an interesting question in my mind: How many photos of astronauts on the lunar surface are there where the astronaut's face can be seen, and the astronaut identified?

 

[Belz...]

Why are we still talking about this ? I thought it was settled.

 

[Southwind17]

Why are we still talking about this ? I thought it was settled.

You just don't take the time to follow threads properly do you! I suggest you read Posts #772 to #774 above for the answer to your question, and please pay attention to what I pointed out to PixyMisa, although it should go without saying, but some people here seem not to realize: PLEASE FEEL FREE TO WANDER OFF!
Actually, why not have a go at the challenge I set above (I assume you didn't read that either!). I've just run Groves' analysis with the FOV figure that PhantomWolf confirms above, namely 49.2 degrees, i.e. the NASA documented figure. Guess how much difference it makes to his calculations and conclusions? Zilch! That said, I think that figure of 49.2 degrees is only potentially valid with an image width of 55mm, and as I've written above I'm confused over the apparent inconsistency that that raises given the 70mm format cameras that the astronauts supposedly used.

Incidentally, it's pretty evident from all of your posts, including other threads, that you have very limited, if any, constructive contribution to make to any intelligent discussion. It seems to me that the total sum of your 'contribution' to this Forum amounts to keeping your head below the parapet by siding with the masses and chipping in with sarcy, smart-arse comments when you find the time, that serve only as slave to your own self-gratification.

Oh well, time to hit the 'ignore' button again, and probably keep it that way this time!

 

[Shrinker]

You just don't take the time to follow threads properly do you! I suggest you read Posts #772 to #774 above for the answer to your question, and please pay attention to what I pointed out to PixyMisa, although it should go without saying, but some people here seem not to realize: PLEASE FEEL FREE TO WANDER OFF!
Actually, why not have a go at the challenge I set above (I assume you didn't read that either!). I've just run Groves' analysis with the FOV figure that PhantomWolf confirms above, namely 49.2 degrees, i.e. the NASA documented figure. Guess how much difference it makes to his calculations and conclusions? Zilch! That said, I think that figure of 49.2 degrees is only potentially valid with an image width of 55mm, and as I've written above I'm confused over the apparent inconsistency that that raises given the 70mm format cameras that the astronauts supposedly used.

Incidentally, it's pretty evident from all of your posts, including other threads, that you have very limited, if any, constructive contribution to make to any intelligent discussion. It seems to me that the total sum of your 'contribution' to this Forum amounts to keeping your head below the parapet by siding with the masses and chipping in with sarcy, smart-arse comments when you find the time, that serve only as slave to your own self-gratification.

Oh well, time to hit the 'ignore' button again, and probably keep it that way this time!

70mm is the physical width of the film including sprocket holes, not the image projected onto the film. A gate or mask within the camera determines the size of the exposed portion on the film. This page discusses the issue with respect to motion picture cameras. A quick google didn't turn up anything for stills cameras but the principle (and the film) is the same.

FWIW, I think you should continue to discuss the subject if you want to learn more about photographic analysis and the tricks of conspiracy theorists. And I don't think it's beyond possibility that anyone here could make a mistake in their counter-analysis. Carry on...

 

[Southwind17]

70mm is the physical width of the film including sprocket holes, not the image projected onto the film. A gate or mask within the camera determines the size of the exposed portion on the film. This page discusses the issue with respect to motion picture cameras. A quick google didn't turn up anything for stills cameras but the principle (and the film) is the same.

FWIW, I think you should continue to discuss the subject if you want to learn more about photographic analysis and the tricks of conspiracy theorists. And I don't think it's beyond possibility that anyone here could make a mistake in their counter-analysis. Carry on...

If you're being genuine with this last paragraph, thanks.

Everything I've read, so far, though, basically says that the FOV can be calculated from the focal length of the lens and the format size as:

A = 2 arctan d / 2f

Where d is the actual dimension of the format (in the same direction) and f is the focal length.

This formula becomes slightly more complex when focusing close up compared to the focal length.

So, are we possibly saying that although the camera format is 70mm that's NOT the figure we should be using to calculate the FOV, even though all the literature seems to say so?

Where have all the budding photographic experts gone?!

 

[Shrinker]

If you're being genuine with this last paragraph, thanks.

Everything I've read, so far, though, basically says that the FOV can be calculated from the focal length of the lens and the format size as:

A = 2 arctan d / 2f

Where d is the actual dimension of the format (in the same direction) and f is the focal length.

This formula becomes slightly more complex when focusing close up compared to the focal length.

So, are we possibly saying that although the camera format is 70mm that's NOT the figure we should be using to calculate the FOV, even though all the literature seems to say so?

Where have all the budding photographic experts gone?!

Absolutely, you need to use the actual image size, not the format size. I don't know about individual camera types to know whether you can assume an image size given the format.


Edit: you also need to know whether the image you are analysing has been cropped. A full scan ought to include the gate itself (usually seen as a slightly fuzzy black border with rounded corners). If it doesn't how do you know you haven't lost a bit of the image during developing, reproduction or scanning?

 

[Belz...]

Incidentally, it's pretty evident from all of your posts, including other threads, that you have very limited, if any, constructive contribution to make to any intelligent discussion. It seems to me that the total sum of your 'contribution' to this Forum amounts to keeping your head below the parapet by siding with the masses and chipping in with sarcy, smart-arse comments when you find the time, that serve only as slave to your own self-gratification.

That's alright, Wind. I prefer the smart-ass comments to being a complete ignoramus like you.

ETA: And considering what you've also found "evident" before, I'm not particularily insulted.

Oh well, time to hit the 'ignore' button again, and probably keep it that way this time!

Don't worry, by the time you're done ignoring everyone who disagrees with you, you won't have anybody but yourself to listen to. That should sound pleasing to you.

 

[CurtC]

I'll tell you what, in order to try to resolve this apparent anomaly, I'll lay down a challenge to you and everybody else still reading this thread: I challenge somebody to reconcile sensibly and objectively, by calculation the following three aspects of the photo:

1. The distance between the two astronauts derived from the field of view.

Haven't we done this already?

• The distance between the two astronauts derived from a shadow analysis.

I'm not sure this is possible with any degree of accuracy. Certainly nowhere near the accuracy you could get from the first method.

• The height difference between the two astronauts (I'd be happy if this is only estimated by observation of the photo, within reason, of course!)

I know we've done this, because I did it myself. Imagine Armstrong standing right next to Aldrin, Armstrong with the camera on his chest. The famous image caught Aldrin right about eye level, so what's the difference between Armstrong's camera height and Aldrin's eye height? Somewhere around 20 to 25 cm. That's how much higher the ground would have to be underneath Armstrong to produce that photo.

Edit: you also need to know whether the image you are analysing has been cropped.

Fortunately, the Apollo Hasselblads had those convenient reseau marks for that.

 

[Southwind17]

CurtC - I think you might have missed slightly what the challenge is. It's not simply to identify the three measurements, it's to reconcile them, and I say 'reconcile' because, to my mind, the shadow analysis, even a close approximation, seems to derive a distance nothing like any of the figures that have been suggested from the FOV derivation. That's why I'm not so fussed about getting the difference in height between the two astronauts right, because it has little impact on the outcome.

Imagine that the lunar surface were flat. At a 15-degree sun angle Aldrin's shadow would be around 6.5m long, allowing for a reduction in height of 200mm for the depression that he's standing in. I doubt that anybody would seriously deny that Armstrong seems to be standing at a distance from Aldrin pretty close to the shadow length, based on the reflection. In order to foreshorten the shadow to the distance calculated by Thabiguy, the incline between Aldrin and Armstrong would need to be in the order of 15-20 degrees (around 1:3), assuming Aldrin is already about 200mm lower. That seems wholly inconsistent with what we see in the photo.

Haven't we done this already?

Well Thabiguy did it, and I disputed it, and nobody has verified it one way or the other. The confusion over how one calculates FOV has only served to muddy the waters, in my mind. Regardless, both Groves' figure and Thabiguy's are inconsistent with what the shadow analysis derives.

I'm not sure this is possible with any degree of accuracy. Certainly nowhere near the accuracy you could get from the first method.

I believe, given what I've written above and recently, that Armstrong's position viz the shadow length can be estimated, certainly with a degree of accuracy (as anything can, technically), but actually with a good degree of accuracy. Where would you say he's standing in relation to the end of the shadow? How much margin for error would you reasonably allow?

I know we've done this, because I did it myself. Imagine Armstrong standing right next to Aldrin, Armstrong with the camera on his chest. The famous image caught Aldrin right about eye level, so what's the difference between Armstrong's camera height and Aldrin's eye height? Somewhere around 20 to 25 cm. That's how much higher the ground would have to be underneath Armstrong to produce that photo.

OK, let's go with either one of those figures then; it makes insignificant difference.

Fortunately, the Apollo Hasselblads had those convenient reseau marks for that.

So what are you suggesting?

Any views on my comment re. the reflective visors?

 

[phunk]

Imagine that the lunar surface were flat.

If you start off with a false premise, the rest of your analysis is doomed.

 

[Belz...]

Imagine that the lunar surface were flat.

 

[Southwind17]

If you start off with a false premise, the rest of your analysis is doomed.

How can 'imagining' something be a 'false premise'? I suppose I could have written 'assume' instead, which, equally, is not a false premise, particularly when that assumption is used as a means to an end, and is exchanged later with facts, or eliminated completely. In order to calculate the effects that an incline has on shadow length it's helpful, if not essential, to start by calculating the shadow length on a flat surface.

What's really 'doomed' is the idea of coming into a thread late erroneously thinking that you understand what's being discussed and purporting to make a meaningful contribution when you don't take the time to read up and, therefore, completely miss the point and/or substance. That's what's 'doomed'!

 

[tsig]

I disagree, and I sense that you have a preference not to analyse this photo any further. Whilst Aldrin's shadow does indeed fall to the side of Armstrong it is patently clear from the reflection in Aldrin's visor that the length of the shadow is equivalent to the distance between the two astronauts, by a reasonably close approximation. The critical parts of the reflected image, namely the point where Armstrong is standing and the end of Aldrin's shadow, fall pretty close to the centre of Aldrin's visor, where the least distortion would occur. I think it's pretty safe to say that the tip of Aldrin's shadow sits off to the side of where Armstrong is standing by a distance significantly less the the height of Armstrong. I'd estimate the distance as little or no more than 1.5m, and the lunar surface at that point can be seen to be essentially flat.

I'll tell you what, in order to try to resolve this apparent anomaly, I'll lay down a challenge to you and everybody else still reading this thread: I challenge somebody to reconcile sensibly and objectively, by calculation the following three aspects of the photo:

1. The distance between the two astronauts derived from the field of view.
2. The distance between the two astronauts derived from a shadow analysis.
3. The height difference between the two astronauts (I'd be happy if this is only estimated by observation of the photo, within reason, of course!)

So, let's see who's up for the challenge!

One other thing that seems odd to me with this photo that I've not considered before: Given that the sun is essentially behind Aldrin, if I were Aldrin I think I would have preferred to raise the reflective visor on my helmet. I'm pretty sure I would have much preferred to have my face on the image rather than a reflection of the surroundings (no, I'm not boasting; I'm no Johnny Depp!). I would at least have thought one photo of each would have been a good idea.

This raises an interesting question in my mind: How many photos of astronauts on the lunar surface are there where the astronaut's face can be seen, and the astronaut identified?

Just take a picture. Look at it. You were not in charge.

 

[tsig]

If you're being genuine with this last paragraph, thanks.

Everything I've read, so far, though, basically says that the FOV can be calculated from the focal length of the lens and the format size as:

A = 2 arctan d / 2f

Where d is the actual dimension of the format (in the same direction) and f is the focal length.

This formula becomes slightly more complex when focusing close up compared to the focal length.

So, are we possibly saying that although the camera format is 70mm that's NOT the figure we should be using to calculate the FOV, even though all the literature seems to say so?

Where have all the budding photographic experts gone?!

Someday you will find a map.

This map will be printed on soft paper.

It will show you great treasure.