A correct attribution for the "Flash Effect" photo?

Discussions about the history of the ship, technical details, etc.

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hans zurbriggen
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Re: A correct attribution for the "Flash Effect" photo?

Post by hans zurbriggen » Tue Jan 21, 2020 7:22 am

Hello,
history is always written by winners and Mr.Jurens is right: this don't preclude it can be in some cases written accurately.
When there are however controversial aspects, I have never seen losers version of history to become the accepted one. In these cases, always winners impose their point of view and only after many years a revision may possibly be done (and only if anyone is willing to undertake a review).

hans

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Re: A correct attribution for the "Flash Effect" photo?

Post by hans zurbriggen » Tue Jan 21, 2020 7:23 am

Hello,
the "flash" photo interprtations from Mr. Nilsson, Mr. Jurens and Mr. Virtuani seem all realistic possibilities to me. Thanks for your excellent drawings and explanations.
Mr. Wadinga: you say 'an extended plane through the muzzles intersects the Bismarck'. This is just an optical effect, the plan can intersect Bismarck course in front or behind her, depending from the muzzle orientation combined to the cameraman position, the camera focal length and the ships relative positions. There is no way to determine where this plan precisely intersect Bismarck track.
In this sense, Mr. Virtuani assertion that there are multiple possible geometric solutions is absolutely acceptable to me.

hans

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Re: A correct attribution for the "Flash Effect" photo?

Post by pgollin » Tue Jan 21, 2020 12:37 pm

.

Re. "history is written by the winners"

In this instance who were/are "the winners" ?

At the Denmark Strait, the Germans were the "winners", overall the British/Allies were the "winners".

.

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Re: A correct attribution for the "Flash Effect" photo?

Post by wadinga » Tue Jan 21, 2020 6:32 pm

Fellow Contributors,

P Gollins' observation is spot-on, the glib and clichéd phrase is particularly inappropriate for Denmark Straits.

Hello Hans and welcome to the discussions. You may have discovered controversy has raged for some time over the relative positions, but it is always interesting to get a new perspective.

Speaking of perspective, I would like to question one element:
Mr. Wadinga: you say 'an extended plane through the muzzles intersects the Bismarck'. This is just an optical effect,
I agree that a sighting directly along the line of the muzzles would be definitive and since the photographer is ahead and closer to the left hand muzzle than the right, it is not possible to be 100% sure. However, we are not talking of alignment with a tiny "vanishing point" on the distant horizon, but with a 50,000 ton battleship only a few hundred metres away and thus covering a considerable arc within the field of vision.

Although some have claimed to be able to determine vessel positions on a second by second basis with incredible accuracy, I think a more prevalent view is that such a feat is impossible, given the limited information we have. We could however establish a few highlights from photo evidence and so I raised five questions WRT to the Flash Effect photo NH 69730. It would be interesting to hear your observations on them. There are other photos which bear close scrutiny too, as well as some which have been withheld from publication, but may in time become available.

At the bottom of page one of this thread, Mr Virtuani posted a comparable picture taken from PoW and yet it is clear the alignment through the barrels in this case go nowhere near Hood. It is also interesting that this picture unavoidably includes deck clutter and railings. IMHO there is none in NH69730 because the photographer is so close to the muzzles that such extraneous detail is outside the field of view of the camera.

I hope that we can keep a lively level of discussion going.

All the best

wadinga
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Re: A correct attribution for the "Flash Effect" photo?

Post by Byron Angel » Wed Jan 22, 2020 2:48 am

Hi Wadinga,
Allowing for all the uncertainties related to the image, I'm speculating that Bismarck was at least a thousand yards from Prinz Eugen when the shutter was snapped.

Having been in the shipping trade, I can say from experience that a large ship (let's say a 10,000 TEU container ship for example) 200 yards distant is HUGE to the eye.

FWIW.

Byron

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Re: A correct attribution for the "Flash Effect" photo?

Post by wadinga » Wed Jan 22, 2020 10:43 am

Fellow Contributors,

Having worked at sea myself for over a dozen years I can see where Byron is coming from. However, having taken quite a few photos during that time I have often been disappointed by how small vessels appear, even when comparatively close, when shot with the "standard" lens which is surely specified around capturing terrestrial landscape shots. The eye and mind can concentrate on that which is of interest in a seascape, whereas the lens captures its entire field of view, including the tedious expanse. In this case the extraneous detail are the 105mm muzzles, with the photographer maybe 30 degrees ahead of the plane of the muzzles. What is also missing are any extraneous deck details, handrails etc showing the photographer is close to the edge and also close to the muzzles, which are obviously not deployed and not in action, ie elevated. If the mount were swung out at all, the photographer would have to be moved rapidly further away both to stay on deck and maintain the 30 degree relationship, in which case rails and deck would surely intrude into the image.

This photo is often cropped in publication to "lose" the muzzles, which are a distraction for the average viewer, but the version which includes them still has Bismarck dominating a huge section of the available field of view, indicating that she is indeed very close. Observations about the slowness of contemporary telephoto lenses, their inability to focus close objects like the muzzles as well as their target, and a limited field of view leaving out objects 30 degrees off their centreline should be borne in mind. This is surely a standard lens and if the maximum image size available includes only the muzzles, the normal published image is not a hugely enlarged fragment from a much larger field of view.

It would be interesting if Bill were prepared to give a little instructional detail about how he arrived at his heavily qualified estimate of distance:
It appears as though the photographer exposed the frame through the airport at frame 88.8 from the mannschaftskuche on the Oberdeck looking more or less perpendicular to the centerline. If so, and assuming that a 50mm focal length lens was used (which would be typical for a 35mm camera of the period) this geometry, if extrapolated, would suggest that at this point Bismarck was only about 230 meters distant. This seems very close, so I’m a bit skeptical about this latter finding, but present it ‘for what it is worth’ without further analysis, and subject to revision.
I still think the muzzles of the forward mount are the best candidate, but then that is just my opinion. I really wish some of these hidden photos would come to light so they can be evaluated too.

All the best

wadinga
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Re: A correct attribution for the "Flash Effect" photo?

Post by Bill Jurens » Wed Jan 22, 2020 5:03 pm

The photo geometry to estimate Bismarck's distance goes roughly as follows:

The vertical offset of the muzzles, assuming they are horizontal and using drawings of the mount as a guide for the distance between the muzzles, allows one to construct a line angled downwards pointing at the camera. The height of the muzzles above the deck is known, and the angled line just found gives a rough idea of the photographer's distance from the muzzles, as one can locate, via geometry, the point at which the angled line intersects a reasonable eye line for a 35mm camera.

Given the distance to the camera, the (assumed) focal length, and the diameter of the muzzles, one can geometrically construct the size of the muzzle image on the actual negative. One can then compare the height of Bismarck to the size of the of the muzzle image, place this new dimension on the negative and thereafter project backwards through the lens to create a 'wedge' for the height of Bismarck proceeding outwards. Geometrically, one can then find the distance at which the lines of this wedge intersect the actual height of the ship.

That gives your the distance to Bismarck.

It's a long chain to be sure, and subject to a variety of errors, insofar as the very precise determinations of certain values -- e.g. the height of Bismarck, the diameter of the muzzles, the focal length of the lens, and the eye-height of the photographer -- are somewhat problematical and the solution is quite sensitive to small errors in the values assumed. But, assuming the assumptions are reasonable, it should put one somewhere in the ball-park...

That's where I got my estimate. With the emphasis on estimate.

Bill Jurens

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Re: A correct attribution for the "Flash Effect" photo?

Post by hans zurbriggen » Wed Jan 22, 2020 5:45 pm

Hello,

About Mr. Wadinga questions:
1.Yes, due to their shape.
2.No, or just only very roughly.
(Two different plans for the two muzzles appear to be present, due to perspective effect from photographer POV: the left and right gun bores are seen from very different angles. For this reason I agree the photographer is quite close to the guns).
3.No. 30 is too much. According to my calculation (I can share) it should have been maximum 15 degrees ahead of the nearest muzzle end plan. Less from the other muzzle end plan. Muzzle bearing and elevation is unknown, therefore position of the photographer cannot be determined.
4.They appear so. Too many variables are missing to say if elevated or depressed (anyway not too much in my opinion). Different is the photo at the bottom of page one of this thread referenced by Mr. Wadinga, where guns appear to be elevated (while they are most probably not).
5. Such conclusion can not be derived as a logical consequence of 3 and 4.

I consider impossible to determine where is photographer, what is guns training and elevation and what are the courses of the ships only analyzing this photo.
Considering also the Prinz Eugen map, I think both Mr. Nilsson and Mr. Virtuani (using Mr. Bonomi image) drawings to be the most probable (and also the only) conclusions that can be derived from this image.



About a 'second by second' battle development (referenced by Mr.Wadinga), I'm in the process to study all recent threads (and requesting some books I have not). There is a lot of information. I have no clear idea yet and I will not express my opinion yet.

hans

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Re: A correct attribution for the "Flash Effect" photo?

Post by Bill Jurens » Thu Jan 23, 2020 2:32 am

The angle between the camera and the muzzles can be determined -- if one has a sufficiently sharp image -- by measuring the ratios between the major and minor axes of the ellipse cast by the circular muzzles on the image plane. The ratio is related to the tangent of the angle. But the images I've seen are really not good enough to make that sort of estimate too reliable. I get (very roughly) seven degrees or so.

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Re: A correct attribution for the "Flash Effect" photo?

Post by hans zurbriggen » Thu Jan 23, 2020 9:52 am

Hello,
the angle posted by Mr.Jurens may be related to the distant right muzzle, the close left muzzle appear to be seen from a 10-15° ahead of the plan through muzzle.
My calculation, based on trigonometry, assumes the ellipse minor axis is linked to the sin(angle) not to the tan(angle). If tan(angle) is used, at 90°from the plan the minor axis would be infinite compared to the major and not equal. For small angles, difference is negligible. I agree the image is not good enough to have a more precise evaluation that a rough estimation.
As I said, 30° ahead is far too much from both muzzle end plans because the minor axis would appear half of the major axis and it is not such a case. Depending from muzzles orientation, the position of the photographer can be almost any point ahead of the 105 gun place.

hans

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Re: A correct attribution for the "Flash Effect" photo?

Post by wadinga » Thu Jan 23, 2020 3:50 pm

Fellow Contributors,

My original guesstimate for the angle ahead of the muzzle plane was simply by eye, but I would like to revise it down to 20 degrees. I have not attempted to evaluate the ellipses, since , in my opinion the photo quality is not good enough. However since the outer barrel overlaps the inner one, and the length of this overlap can be estimated in terms of gun barrel diameter on the photograph, I used the following method. I drew a series of lines at 10, 20 and 30 degrees from one gun muzzle on a plan of the mount in Miroslaw Skiwiot's book German Naval Guns 1939-1945 and then parallel lines through the inner margin of the end of the other and the one where the apparent overlap matched the photograph at about 1.5 barrel diameters was 20 degrees.

If the left and right guns were actually being seen from "very different angles" the photographer would have to be very close indeed, since the distance between the barrels is only 70cm. While decreasing the angle ahead of the muzzles to 20 degrees does increase slightly the distance ahead of the mount where the photographer can stay "on the deck" were the mount to be rotated outboard, it is not by much.

Hans, could you explain why you say :
2.No, or just only very roughly.
Since drawing a perspective line through the centre of the ellipses you have used would surely intersect Bismarck amidships. I suspect that if the photographer had moved a little to the right and had been exactly on the plane of the muzzle ends Bismarck would line up exactly.

I also can't imagine any situation where the barrels could be significantly elevated or depressed and still appear parallel to the horizon given the important factor that the POV is almost at the same level as the inner gun which obscures most of the outer. If the POV is significantly higher or lower than the gun it might give a false impression vis a vis the horizon, but that is not the case here.
For this reason I agree the photographer is quite close to the guns).
Depending from muzzles orientation, the position of the photographer can be almost any point ahead of the 105 gun place.
Do we agree the photographer is close to gun muzzles eg 2-5metres or do you consider he could be at some other distance along the deck?

All the best

wadinga
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Re: A correct attribution for the "Flash Effect" photo?

Post by Bill Jurens » Thu Jan 23, 2020 5:00 pm

My estimate is something in the vicinity of two meters assuming a 35mm camera ( or a "press camera") , held at eye level. If it were a twin-lens, or some of the Graflex press types, the camera would be held somewhat lower and the distance correspondingly greater. Perhaps three meters... Without more information about the camera, it's hard to tell. It probably wouldn't be MUCH greater, though. Less than 10 meters.

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Re: A correct attribution for the "Flash Effect" photo?

Post by paul.mercer » Thu Jan 23, 2020 5:51 pm

Gentlemen,
Another rather naive question I'm afraid, would the a photographer be standing in the open that close to the muzzles of a gun even if it was only 4.1" in the middle of a battle when it is likely to be fired?
One would have thought that it would not be good on the ears!

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Re: A correct attribution for the "Flash Effect" photo?

Post by Bill Jurens » Thu Jan 23, 2020 6:45 pm

That's what I suggested earlier. The chances of having a photographer wandering about the weather decks and basically just getting in the way in a combat situation are pretty slim. That's why my guess was that the photo was exposed from inside the galley, looking through an open air port. The geometry matches pretty well.

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Re: A correct attribution for the "Flash Effect" photo?

Post by Herr Nilsson » Fri Jan 24, 2020 8:22 am

I have to raise objections.

It's pretty unlikely that there were open air ports or doors or anything else. The ship is in battle condition.

However, I found a picture in my collection, which probably was taken on May 23rd:
PG23.5.41 cr.jpg
PG23.5.41 cr.jpg (6.73 KiB) Viewed 276 times
Last edited by Herr Nilsson on Fri Jan 24, 2020 8:28 am, edited 1 time in total.
Regards

Marc

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