# moon picture question **URL:** \ **Category:** Factual Questions\ **Created:** [April 1, 2002, 1:01pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192 "2002-04-01T13:01:26Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Knighted\_Vorpal\_Sword](https://avatars.discourse-cdn.com/v4/letter/k/ac91a4/32.png) [@Knighted\_Vorpal\_Sword](https://boards.straightdope.com/u/Knighted_Vorpal_Sword)\ **Post date:** [April 1, 2002, 1:01pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/1 "2002-04-01T13:01:26Z")
On many pictures of the moon, there are lots of crosses. Why are they there, and what are they for? See, for example: [http://antwrp.gsfc.nasa.gov/apod/astropix.html](http://antwrp.gsfc.nasa.gov/apod/astropix.html) ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [April 1, 2002, 1:21pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/2 "2002-04-01T13:21:05Z")
Hassleblad (spell?) the camera maker put them on the lens for targetting. The astronauts looked through the lens when targetting pics = these “crosshairs” helped. ---
**Author:** ![Photog](https://avatars.discourse-cdn.com/v4/letter/p/c77e96/32.png) [@Photog](https://boards.straightdope.com/u/Photog)\ **Post date:** [April 1, 2002, 1:27pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/3 "2002-04-01T13:27:28Z")
> [@](#): > > \*Originally posted by Philster \* > \*\*Hassleblad (spell?) the camera maker put them on the lens for targetting. > > The astronauts looked through the lens when targetting pics = these “crosshairs” helped. \*\* Well, not exactly. The marks, created by something known as a Reseau plate, are there to provide a standard of measurement when analysing the photos. From [this site](http://www.hq.nasa.gov/office/pao/History/alsj/a11/a11-hass.html) > [@](#): > > The Data Camera was fitted with a so-called Reseau plate. The Reseau plate was made of glass and was fitted to the back of the camera body, extremely close to the film plane. The plate was engraved with a number of crosses to form a grid, and the intersections were accurately calibrated to a tolerance of 0.002 mm. The crosses are recorded on every exposed frame and provided a means of determining angular distances between objects in the field-of-view. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [April 1, 2002, 1:44pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/4 "2002-04-01T13:44:11Z")
Photog…nice backup there! So they were on the plates, huh? It always comes up in “they faked the moon landing” arguements. I tell folks that the camera maker intentionally had those crosshairs on the lens - but I can be more accurate now. -thanks ---
**Author:** ![Photog](https://avatars.discourse-cdn.com/v4/letter/p/c77e96/32.png) [@Photog](https://boards.straightdope.com/u/Photog)\ **Post date:** [April 1, 2002, 2:05pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/5 "2002-04-01T14:05:06Z")
> [@](#): > > I tell folks that the camera maker intentionally had those crosshairs on the lens A bit more ‘ammo’ for you: Anything etched into the lens will be rendered out of focus on the film. Furthermore, marks on the lens itself will appear out of focus to the photographer looking through the camera, and could not therefore be used for “targeting” as you mentioned in your earlier post. The Reseau plate is positioned just in front of the film plane so that the marks will be rendered sharply on the neg (think of contact printing in which the negative is placed directly on the photographic paper to produce a positive image). Because of the position of the plate, the photographer cannot see the marks that create the grid on the film. Therefore, once again these marks cannot be used for “targeting”. There may very well have been marks etched onto the **focusing screen** that could have been used for targeting. But, again, because of the postion of the focusing screen, these marks are not recorded on the film. ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [April 1, 2002, 5:16pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/6 "2002-04-01T17:16:12Z")
One of the photos I saw from the fake moon landing program showed a close-up of the flag they planted…with one of those crosses partially hidden behind the flag…arguing proof that the photo was retouched and/or edited. ---
**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\ **Post date:** [April 1, 2002, 5:16pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/7 "2002-04-01T17:16:44Z")
What the moon hoax proponents say about the crosshairs is that there are some images where the thing being photographed goes _through_ the crosshairs, allegedly showing that the crosshairs were added later. As in all other evidence for the moon hoax, a little information is a dangerous thing. Anyone who knows just a little more about film photography knows that overexposed parts of an image will bleed to be slightly larger than they should be, because light gets scattered by the film emulsion to expose areas that might be shadowed with the direct light from the lens. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [April 1, 2002, 5:40pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/8 "2002-04-01T17:40:37Z")
> [@](#): > > What the moon hoax proponents say about the crosshairs is that there are some images where the thing being photographed goes through the crosshairs, allegedly showing that the crosshairs were added later. Which kind of begs the question “Why would people faking the moon landing add fake crosshairs to the pictures in the first place?” 😕 Maybe it’s better not to ask. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [April 1, 2002, 6:58pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/9 "2002-04-01T18:58:39Z")
In all of the cases where a portion of the crosshair appears “hidden” it is “behind” a white object which is overexposed slightly. As anyone who’s played with cameras knows, when you overexpose an object it tends to “bleed” on the film, washing out detail. The film behind the crosshairs which would normally remain unexposed (thus black) become exposed due to the bleeding effect. This is pretty easy to simulate with any SLR camera here on Earth. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [April 1, 2002, 9:00pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/10 "2002-04-01T21:00:03Z")
> [@](#): > > \*Originally posted by friedo \* > \*\*In all of the cases where a portion of the crosshair appears “hidden” it is “behind” a white object which is overexposed slightly. As anyone who’s played with cameras knows, when you overexpose an object it tends to “bleed” on the film, washing out detail. The film behind the crosshairs which would normally remain unexposed (thus black) become exposed due to the bleeding effect. This is pretty easy to simulate with any SLR camera here on Earth. \*\* Absolutely correct; photographic emulsion is composed of tiny crystals (usually of silver compunds); not all of the photons that hit each crystal (or indeed the spaces between the crystals) are immediately absorbed - a certain proportion are dispersed and end up activating other crystals nearby. Usually this isn’t noticeable, but for intense light sources, it happens and is a well-understood effect; conspiracy theorists clutching at this particular straw are merely parading their ignorance. ---
**Author:** ![The\_Bad\_Astronomer](https://avatars.discourse-cdn.com/v4/letter/t/f05b48/32.png) [@The\_Bad\_Astronomer](https://boards.straightdope.com/u/The_Bad_Astronomer)\ **Post date:** [April 1, 2002, 9:43pm UTC](https://boards.straightdope.com/t/moon-picture-question/101192/11 "2002-04-01T21:43:43Z")
Have you tried [here](http://www.badastronomy.com/bad/tv/foxapollo.html#crosshairs), or [here](http://www.clavius.org/photoret.html)? 😉