Priority vs Final Readout of Lunar Orbiter Images


Dennis WIngo: This image (click on image to enlarge) shows the sequence of images that were read out during what is termed “priority” readout vs the “final readout”. The priority readout was an opportunistic scanning of processed photos on the lunar orbiter before all of the images were taken. The photo process with the 70mm film began with an image being simultaneously taken by the 610 mm high resolution camera and by the 80 mm medium resolution camera. In a process remarkably similar to the old polaroid dry process instamatic cameras, the film was dry processed by a “bimat” dry processor. The bimat would separate from the film (most of the time) but would sometimes due to the timing would leave artifacts on the image, which are readily identified on the film.
The film would then be fed into the readout looper where it could be scanned and the images sent back to the Earth. During the mission when photographs were still being taken the film would run one direction through the looper. After all of the images were taken a command would be sent to cut the bimat and then the film could be read in the opposite direction.
Thus when we start with a low numbered tape, the first images that come off are from the priority readout in ascending order. However, the ascending order is not linear, jumping because images are still being taken and the film advancing while the spacecraft cannot transmit. The image of the day today shows what images are taken in ascending sequence (orbit) format. You can see the jumps. If you are really good you can see what images we are recording and then predict what the next images will be … At least during the priority readout.

How Do We Find Lunar Orbiter Images?

Dennis Wingo: Several people were interested in our process yesterday so here is some more information on what we do to figure out the images on the tapes. [Click on image to enlarge].
We almost always start with the low numbered tapes and go up, just like in the real mission. As stated yesterday, we picked Woomera because it had the most ground station time. There is 163 tapes for the Woomera LO-V, more than 50-60 tapes than for the previous LO’s. We think that there is some duplication there but we won’t know until we get all of the Woomera tapes done, then process the raw framelets. Austin then generates a report based upon our knowledge of all of the framelets for LO-V, which then tells us what we have left to do. We then will start on the Goldstone tapes.

Continue reading “How Do We Find Lunar Orbiter Images?”

Video: Oscilloscope Trace of Lunar Orbiter Image Playback


Dennis Wingo: This is a two minute video that shows, about every 42 seconds, a shift in the video. This occurs when the line is scanned to the end of a framelet, over the calibration features that were pre recorded in the tape. Keith has posted images here that show the relationship between the scope trace and the dynamic range of the tapes. This gives us a qualitative measure of the performance of the tape drive. Even in its sub optimized state today, the scope trace almost exactly matches the original transfer function of the spacecraft film, thus giving us a means to evaluate the quality of the analog data derived from the tape.

Using Software to Rectify a Photo About Mechanical Photo Rectification


Original caption: St. Louis, Mo. — RECTIFYING A LUNAR PHOTO — Mr. Ralph Wilson of the U.S. Air Force Aeronautical Chart and Information Center uses photographic equipment to rectify a composite of Lunar Orbiter Photos. Rectification is accomplished by tilting the composite on the easel until the crater and other features can be photographed at a predetermined angle. (U.S. Air Force Photo).
Keith Cowing: I found this photo on eBay. As you can see it was warped. So I used Photoshop to do a quick “rectification” so as to present the photo as it would have looked if it was laid flat. Back in the Lunar Orbiter days they did not have Photoshop – so they had to use this mechanical / optical process – one that had a clear military heritage.
Click on top image to enlarge.

A Lunar Orbiter Image Last Seen 47 Years Ago


After being forgotten for nearly 47 years, three high resolution images taken by the Lunar Orbiter II spacecraft have been rediscovered by the Lunar Orbiter Image Recovery Project (LOIRP). It is unlikely that anyone has seen these images since they were sent back to Earth. Indeed, it is unlikely that very many people saw them at that time either.
The three high resolution images were taken along with a medium resolution image on 23 November 1966 at 17:05:39 GMT. The center point of the images was 26.94 West Longitude, 3.196 degrees North Latitude. The images were taken at an altitude of 43.6 km and the image resolution is 0.93 meters.
We recently came across these three images (#2159) and noticed that they do not appear online at the LPI Lunar Orbiter database. Only the medium resolution image gets mentioned at LPI.
These three images were retrieved from original Lunar Orbiter program analog data tapes yet they appear nowhere in NASA’s publications. They do appear on microfilm archives at LOIRP and are mentioned in a simple data log online at LPI. LOIRP has a more extensive computer printout of this data that shows more detail about the images – but not the images themselves.
Unless someone happened to be looking through this microfilm collection (LOIRP has the only extant copy) then it is pretty safe to assume that no one has actually seen these images since a technician saw them on a TV monitor in 1966.


– Left Image [larger] [Raw TIFF – very large]
– Middle Image [larger] [Raw TIFF – very large]
– Right Image [larger] [Raw TIFF – very large]
Note: These three images actually comprise portions of a single high resolution image but these high resolution images were traditionally divided up and numbered in three parts by the Lunar Orbiter program.
The Lunar Orbiter project was rather well documented. Indeed, it is this documentation that allowed the LOIRP to figure out what images are located on which tape, but also how to repair and replace hardware on our 50 year old tape drives. In the course of retrieving images from the original analog data tapes we have come across a number of images – some only partial images – that are not included in formal program documentation or listed in LPI or USGS databases.
We have a working theory as to why these images have been forgotten for the past 47 years. There were three ground stations involved in retrieving data from Lunar Orbiters – Woomera, Australia, Madrid, Spain, and Goldstone, California. There is some overlap due to planetary geometry such that images were often recorded by more than one ground station.
When the spacecraft was playing back its imagery there was only one chance to get the data since it was really not feasible (or advisable) to rewind the film and re-scan and retransmit – since there was no ability to store these images electronically on the spacecraft. So, if one or more ground stations did not record data the first time it was sent, there was no second chance.


How data was sent back to Earth and stored as photographs and data tapes. Click on image to enlarge.
Lunar Orbiters shot their images on 70mm SO-243 photographic film. The film was developed aboard the spacecraft, scanned and sent back to Earth as analog data. One data stream demodulated the image and sent it to a high resolution kinescope (TV screen) where the image on the screen was photographed as a photographic positive. Those photographs were subsequently re-photographed to create a negative, then stitched together and photographed again to create photographic prints used for the requirements of the program.
The data was also sent to analog videotape machines where it was recorded for posterity. Given that the data stored on the analog tapes was scanned directly from the film in lunar orbit and recorded as data on magnetic tape these images were of much higher quality than the photos taken off of the kinescope and re-photographed multiple times. These data tapes were used sparingly to digitize small “chits” that were run through computer programs to measure the height of rocks on the surface and the slope of the surface within the landing ellipses chosen based upon looking at the photographic prints. These computer measurements were done to validate the safety of the landing area as this was difficult to do using just the film record.
The photographic process of capturing kinescope images continued as long as data was being received. But the data tapes had to be changed out after several images had been recorded. However, the spacecraft playback continued while the technicians changed out the tapes – and that process took a few minutes. During the time that the tape was being changed out analog data was not being recorded by that ground station – but it might be recorded by another during the overlap period. Then again it might not.
The way that the images came down involved the transmission of a medium resolution version of an area followed by high resolution images of that area. So, tape changeout tended to happen as the medium resolution image came in. That way, at most, a small portion of the medium resolution image was not recorded on tape. But the photographs of the images appearing on the kinescope continued nonstop – hence the presence of these images on our microfilm collection (these microfilm images were originally given to Dennis Wingo from then fellow student Eric Dahlstrom in 1989 after being purchased at surplus from NASA GSFC). The high resolution images were what most interested the Lunar Orbiter project team – the medium resolution images served to place the high resolution images into context.
Detailed information on image 2159. Click on image to enlarge.
You might wonder why each ground station did not have more than one tape drive. Well, given the expense of these drives, they were lucky just to have one at all three ground stations. Most of the time the images were captured without incident, often by more than one ground station.
Sometimes flaws in the film or glitches on the playback system on the spacecraft would cause flawed images to be sent back. Those flawed images were usually of partial use. That said these flawed images were cataloged as part of the detailed program documentation. As good as these folks were with documenting things, some stuff fell through the cracks.
In the case of image 2159 we think that there was some problem with retrieving the image and that it was designated as having a flaw – but that fact never made it into program documentation. The images were on microfilm that were derived from the data tapes. But the high resolution imagery for 2159 was not printed out and assembled into prints for use by the project team. When we retrieved this high resolution image we did encounter some problems that necessitated some hand assembly. This could well have been part of the problem experienced in 1966.
Regardless of the cause(s) we have retrieved the his resolution imagery and have made it public. Over the next few weeks we’ll be releasing some other images which may have suffered a similar fate.
The Lunar Orbiter Image Recovery Project (LOIRP) is located at the NASA Ames Research Center in Moffett Field, CA. Funding and support for this project has been provided by NASA Headquarters, NASA Lunar Science Institute, NASA Ames Research Center, SkyCorp Inc., and SpaceRef Interactive Inc.
For more information on the Lunar Orbiter Image Recovery Project (LOIRP) visit https://moonviews.wpenginepowered.com
For information on NASA’s Lunar Science Institute visit http://lunarscience.arc.nasa.gov/

A Typical Day at LOIRP and McMoons


Original analog data tape from Lunar Orbiter 5 recorded live as data was sent back from lunar orbit in Aug 1967 being played back today (4 Feb 2013) for data recovery and enhancement. Video clip below shows data capture under way.

Video of data collection of #lunarorbiter 5 image at LOIRP ri... on Twitpic

First Earthrise Photo Taken 46 Years Ago Today

Keith’s note: 46 Years ago today, on 23 August 1966, Lunar Orbiter 1 snapped the first photo of Earth as seen from lunar orbit (Larger view). While a remarkable image at the time, the full resolution of the image was never retrieved from the data stored from the mission. In 2008, this earthrise image was restored by the Lunar Orbiter Image Recovery Project at NASA Ames Research Center. We obtained the original data tapes from the mission (the last surviving set) and restored original FR-900 tape drives to operational condition using both 60s era parts and modern electronics. The following links provide background on the image, its restoration, and reactions to its release.
Here is a comparison of the full image in its original, familiar context (higher res)(print quality). You can download a 1.2 GB version from NASA here. Note: this is a very large file.


Newly Restored Lunar Orbiter Image of Earth and Moon (Detail)
How the Photo Was Taken
House of Representatives Honors Lunar Orbiter Image Recovery Project
Nimbus II and Lunar Orbiter 1 Imagery: A New Look at Earth in 1966
Dumpster Diving for Science, Science Magazine
What Lunar Orbiter 1 Was Seeing on 23 August 1966

High Resolution Lunar Orbiter Imagery of Central Uplift Features Inside Copernicus

On 11 August 1967 Lunar Orbiter 5 took one medium resolution and three high resolution images of the central uplift features inside crater Copernicus. These photos exhibit some processing artifacts (splotches) resulting from the film development process aboard the spacecraft. The imagery comparison discussed in the LOIRP poster presentation The Lunar Orbiter Image Recovery Project (LOIRP) Comparison of LO Copernicus Central Uplift with LRO LROC Mosaic at the 2012 Lunar Science Forum is taken from frame h1 – lower right hand portion.

This newly retrieved high resolution image, frame 5151_H3, was taken by Lunar Orbiter 5 on 11 August 1967 at 11:18 GMT LPI reference. Images: [large at LOIRP] [Very Large at NASA NLSI]

This newly retrieved high resolution image, frame 5151_H2, was taken by Lunar Orbiter 5 on 11 August 1967 at 11:18 GMT LPI reference. Images: [large at LOIRP] [Very Large at NASA NLSI]

This newly retrieved high resolution image, frame 5151_H1, was taken by Lunar Orbiter 5 on 11 August 1967 at 11:18 GMT LPI reference. Images: [large at LOIRP] [Very Large at NASA NLSI]

Printing The Moon


Between 1966 and 1967 NASA sent five Lunar Orbiter spacecraft to the Moon. Their job was to survey the surface to help determine landing sites for the upcoming Apollo missions. In addition to their recon role, these spacecraft also contributed to the nascent scientific understanding of the Moon.
At the time that the images were taken using film that was actually developed aboard the spacecraft in lunar orbit, the ability to send back imagery was nothing like it is today. The photos were scanned much like news photos of the day and the data was sent back to Earth. The images were then printed out on photographic paper and used to construct maps of the lunar surface. In so doing a lot of data from the original photos was lost. Luckily NASA had the foresight to listen to the suggestions of project engineers such as Charles Byrne and stored the original data on analog tapes.
Some 40 years after these missions were completed the Lunar Orbiter Image Recovery Project (LOIRP) was begun with the intent of using refurbished tape drives and a complete set of original project tapes (over 1,500). Utilizing funding from NASA the LOIRP team was able to return the original drives to operation such that the data on the tapes could be accessed.
By adding modern computer interfaces and data handling techniques, the LOIRP was able to scan and record the data in ways that simply could not have been accomplished in the 1960s. As a result the images that were obtained had a much higher resolution and dynamic range than had been seen to date. Indeed, in many cases, these images often rival or exceed images taken by the Lunar Reconnaissance Orbiter which is currently surveying the Moon.
As clever as we thought we were, we were not the first team to tackle the issue of generating high resolution imagery. Someone tried to do much of what we were doing today – but did so with technology available in the 1960s. We were recently contacted by someone who had seen our project’s Facebook page. His name is Joe Watson and he worked on a project that used computer printers that worked like giant electric typewriters – but using varying sizes of squares instead of letters. With this system and a lot of creativity, Watson and his team created immense high resolution versions of Lunar Orbiter images from which topographic maps were made.
We had heard some vague stories about such projects but were unaware of just how audacious they were. So, in Joe Watson’s own words, here is the story of a precursor of the LOIRP.

Continue reading “Printing The Moon”