# LarScan Design Home Built 360 Degree Field of View Panorama Cameras

Built from the finest materials that I had on hand

Finest Craftsmanship that I could manage.

# These Really Work!

The story I heard was that Lars Larsen had built several revolving cameras of his own design. While driving down a highway late one night, he was thinking about his biggest design problem... how to control the length of film moving through a revolving camera so that it exactly matches the moving image. EUREKA! At once he he had it - a stationary disc inside of the camera body. As the film was pulled by a motor through the camera it would be held stationary by the disc as the camera body would rotate around it. (Think of pulling yourself along on roller skates by pulling on a rope. You would move the rope would not)The length of film for a 360 degrees would be determined by the circumference of the disc. Doing a little math Lars determined that the diameter of the disk should be exactly twice the focal length of the lens. For a 35mm lens the diameter of the disk must be exactly 70mm and so on. To test his theory Lars used the body of an old 120 folding camera and a wide angle lens from a 35mm format camera. It worked perfectly.

Basic Materials

• 120 film size folding Camera Body. Many brands will work, but in order for the film to be Transported smoothly it is necessary to use a model that has spool holders for both ends of both the supply and take up spools.
• A disk of a known diameter. For 6x6 bodies 70mm is about the maximum that will fit. For a 6x9 body 100mm is the limit. You can turn your own by chucking plastic, aluminum, or other suitable material in a drill press. I use a 1/4 inch bolt for an axle. One builder found a pulley from a broken VCR that just happened to be the correct diameter. Super glue an "O" ring to the circumference to prevent the film from slipping. Bearings are available at hobby shops.
• A lens to match the diameter of the disc. If you are using a 35mm lens the diameter of the disk must be 70mm so use a 6x6 format body. For focal lengths longer than 35mm use a 6x9 format body. I prefer to use a zoom lens. After finishing construction you can simply zoom to the desired focal length. I mount a lens cap, with a whole drilled through the center, to the lens board to act as a lens mount.
• A DC electric gear motor. 6, 12, and 24 volt models work. A friend of mine bought 5 for \$20 each (all that they had in stock at the time) from Skycraft Parts and Surplus, Winter Park, Florida USA 407 628-5634. They are available new in the \$100 range from Stock Drive Products, New Hyde Park, New York USA             516 328-3300      . Some connect the motor to the film take-up shaft directly, others use gears, I cut a grove in the take up knob to convert it into a pulley. I connect the motor and the take up knob/pulley with an  "O" ring.

DC Gearhead motors are available from:

• Herbach & Rademan, 18 Canal Street, Bristol, PA 19007-3939 USA             (215) 788-5583
• Marlin P. Jones & Assoc. http://mpja.com  email: mpja@mpja.com
• Skycraft Parts & Suplus, Winterpark, FL USA             407 628-5634

Bearings and "0" rings are available from:

# What focal length lens should I use?  What size negative do you want? A 20mm lens will give you a 360 DOV that is 4.9 inches long and will fit in a 4x5 enlarger. A 24mm lens will give you a 5.9 inch long 360DOV that can also fit in many 4x5 enlargers. A 28mm will be 6.9 inches, a 35mm will be 8.7 inches, and a 50 mm lens will give you a 12.4 inch long 360 degree field of view panorama. The choice is yours. I recomend using zoom lenses because they allow for ajustments to be made after construction is finished.For a list of focal lengths and the length of the images that they give click here.What is the distance from the film to the lens flange? This varies from camera brand to brand.  (note: Don't make the same mistake that I did. Be sure to make the measurement with film in the body.)Nikon = 46 .5mmMinolta= 43mmOlympus OM= 46mmKonica=40.5mmTake these values as a starting point. Confirm them by doing your own measurements.Please measure other brands. Send values and corrections to bob@panoramic.netHow do you determine what the exposure time is? The formula is... The size of the slit in mm, times the time the camera takes to make a 360 degree turn. Divide this number by 2 times the focal length of the lens in mm times 3.14. The answer will be in the form of a fraction and is the exposure time.

Subject: LarScan works!
From: gbraun@mail04.mitre.org (Gary A. Braun)

I've been working on my LarScan on and off for about 4 months, and just finished it the other day. I shot two rolls of Ektachrome and was astounded that it actually worked (since nothing I makes ever works the first time!)  I'm still getting a bit of minor banding which I attribute to a slightly off-center drive pulley, and I need to recalibrate the "infinity" mark on my lens for sharper images (even though they are very good now).  Otherwise, I'm extremely pleased with the performance.

I used an old Zeiss folding camera for the body, an Olympus 24mm lens which I already owned, and various bits and pieces (DC gearhead motor, bearings, miniature nuts & bolts, etc) from electronic surplus stores and RC model shops.  An excellent source for DC gearhead motors is:

C & H Sales Company
P.O. Box 5356
Telephone             818-796-2628

My next project is to build a pan camera with a surplus 3" Zeiss Planar aerial camera lens.  Hopefully this one won't take as long!
Cheers,
Gary

Hi Bob,
I thought I'd let you know I think I've finally got a fully functional LarScan!! I found the (best) zoom lens setting and expoxied the barrel in place along  with the focus ring so it can not move.  Solved the banding problem related to the take-up spool! I made a  spring out of a piece of 1/32" stainless cut about 3/4" wide and about  3.5" long. Bent it to an elongated "S" shape and drilled a hole in it.
This was attached to an adapter that fits the "hot shoe" mount on the  top of the camera that has a 1/4-20 bolt sticking out the top with a nut and washer to hold it down. With this arraingement I can adjust  the pressure on the spring simply by tightening the nut.

In the future I'd strongly suggest you not deal with fixed focal length lens's. By my observation the size of the disk is critical to match the focal length. When I do the math based on my settings achieved, the disk size is 69.2mm which gives me a focal length of  34.6mm. Nikon claim an accuracy of +/- 1% and my lens must be to the plus side. Their was no way to make the fixed lens work with that disk. A difference of .4mm doesn't sound like much but it must have been enough to keep it from working.

I also got the bearing freed up faily well, I hooked up my Dremel tool  with a rubber band and spun the hell out it for about 15 minutes.  If you're interested, as soon as I get some images that I'm willing to  have "published" I'll send you a few if you should care to use them on  the web site for your advertizing purposes. Let me know.

Thanks,
Mike Rote

# Which Lens Should You Use To Build Your LarScan?

I've been thinking about building a Larscan. . . .and to help me figure out what lens to select, I made up this chart.

The vertical angle shown (rounded) is calculated based on a 43mm image width.  This is the "guaranteed" diagonal for lenses used on 35mm cameras. (In reality, you'll typically get about 46mm, but sharpness and light falloff problems may be apparent.  I chose to use this extra width as "bonus" angle.)  Also shown are some previous Larscan lens selections as well as vertical-angle equivalents for some popular swing-lens and rotational panoramic cameras.

Lens    360
Focal    Degree Image
Length  Length in:        Vertical Angle of View Equivalents
in mm    mm    inches
14        88    3.5        114 Michel Dusariez's Larscan
15        94    3.7        110
16      101    4.0        107
17      107    4.2        103 Michel Dusariez's Larscan
18      113    4.5        100
19      119    4.7          97
20      126    4.9          94
21      132    5.2          91 Lars Larsen's Larscan
22      138    5.4          89
23      145    5.7          86
24      151    5.9          84
25      157    6.2          81
26      163    6.4          79
27      170    6.7          77
28      176    6.9          75
29      182    7.2          73
30      188    7.4          71
31      195    7.7          69
32      201    7.9          68
33      207    8.2          66
34      214    8.4          65
35      220    8.7          63
36      226    8.9          62
37      232    9.2          60
38      239    9.4          59
39      245    9.6          58
40      251    9.9          57
41      258    10.1         55
42      264    10.4        54
43      270    10.6        53 Noblex 150
44      276    10.9        52
45      283    11.1        51 Globuscope
46      289    11.4        50
47      295    11.6        49 Widelux F8, Poundshot 65 w/70rnm
48      302    11.9        48
49      308    12.1        47
50      314    12.4        47 Horizon 202
51      320    12.6        46
52      327    12.9        45 Noblex 135,Roundshot 65 w/220
53      333    13.1        44
54      339    13.4        43
55      346    13.6        43
56      352    13.9        42
57      358    14.1        41
58      364    14.3        41
59      371    14.6        40
60      377    14.8        39
61      383    15.1        39
62      390    15.3        38
63      396    15.6        38 Roundshot 35    (has 3rnm upshift)
64      402    15.8        37
65      408    16.1        37
66      415    16.3        36
67      421    16.6        36
68      427    16.8        35
69      434    17.1        35
70      440    17.3        34

I hope that this is useful.

Regards,
Alan Kafton
alan_kafton@hp.com

Find hereunder information about our book. We don't sell camera, just a book "HOW TO MAKE ONE FOR YOURSELF"

360° PANOPTIC PHOTOGRAPHY EXPERIMENTS
Michel DUSARIEZ, Ludovic PIERROUX & Lars R. LARSEN.

New technical approaches to panoptic photography and the three inventors have been sporting enough to present their findings to the public. Not only do they fairly divide the merits, but they also reveal their invention totally unselfishly, not covering up any of the details. They even add the instructions which enable skilfull amateurs to construct their own panoptic materials, using elements which are simple and inexpensive.
The English version 138 pages is now again available. It examines in details different 360° panoptic system which are easy to built, with diagrams and advice. Additional article,about stereo 3D panoptic photography on 360° and panoptic 360° underwater experiments, as well as Polaroid 360° camera. English version price : 900 BF (about U.S.\$ 26.00), package and airmail postage include everywhere. Only credit cards VISA, MASTERCARD, AM. EXPRESS accepted. Bank cheque can not be accepted. ISBN 2-9600048-1-7.

PANOPTIC PHOTOGRAPHY
Michel DUSARIEZ
14, avenue Capitaine PIRET
1150 Brussels - BELGIUM FAX 32 2 512 68 29

About the exhibition of LARSCAN CAMERAS with pictures made with, from Lars
and me, at the MUSEE DE LA PHOTOGRAPHIE in Charleroi -Belgium - Exibition
from February 14 to April 20, 1997. Michel DUSARIEZ - Brussel - Belgium
March 1997.

Panoramic Conversation or 25 years of turning around.
Michel Dusariez: Since 1986, I have been interested in photographs taken
with Cirkut cameras, which are large format panoramic cameras dating back to the beginning of the century, of which many are still in service, especially in the United States. I started my own exploits in panoptic photography with a transformed Rollei 35 ( April 1987) the reasonable results of which encouraged me to persevere. The way the technical inventor's mind works, means that he is in constant need of efficient tools and materials and has to do with the available means and the constant doubt as to whether he will succeed often means that he reluctant to invest - an cruel dilemma.
A trip to Japan in 1989 with a view to demonstrate the advantages in the use of kites for aerial photography, (1979) and the fact that I met Hideaki Sato, amateur builder of panoramic cameras confirmed me in my intentions. The first results gave me negatives of 250 mm x 24 mm which I thought were far too long, and I decided to go on to build a prototype based on a single use Fuji with a 25 mm lens which gives me negatives of 157 mm x 24 mm. The length/height ratio was improved, but still too long for my taste. This camera was named "Rubbish" (1989) because it was made from scrap parts only and it works quite well. I then came upon the ides of a non-definitive transformation of a modern SLR camera. Cameras with an interchangeable back make it possible to construct a panoptical interchangeable back system with two interchangeable motors for two different speeds. The focal length chosen, was deliberately very short with a view to reducing the negative length. This gives a negative of 106 mm x 24 mm. We reduce the length/height ratio. The camera body itself undergoes no changes and can still be used normally.
At this point in time, I meet the Dane Lars R. Larsen who had already been exploring panoptical photography ( 1970). Lars R Larsen: I had built my first almost panoptical camera (350°) in 1970 with the intention to make panoramas of buildings and interiors. The prototype was built from an alarm clock casing with an internal diameter of 90 mm (2 x the focal length of the lens 45 mm) which gave me negatives of the very unhandy length of abt 270 mm with a height of 24 mm. after a few successful takes, I abandoned the project, but luckily, I kept the camera.
When twenty years later, I met Michel, his system appealed to me, but at the time, I had neither a camera with interchangeable back, nor did I have a 17 mm lens. I wanted to use a 21 mm which I have, and I came upon the idea to let the camera turn around a fixed rubber disc the diameter of which is twice the focal length of the lens. I built the system around a 6x6 Zeiss Ikon Nettar body, so that I could benefit from the #120 format with a film of 60 mm.
Four points are worth mentioning here: 1: a lens for a 24x36 SLR, the focal length of which is shorter than the depth of the camera body is constructed as a retrofocus lens. - the distance between the lens and film is longer than the focal length - which in our case gives us room enough for the abovementionned rubber disc. 2: that the picture circle covered by 24x36 lenses is at least equal to the diagonal of that format, i.e.43 mm. Often it is more and may thus attain twice the height of the 24 mm of a 35 mm film. 3: that the use of a 17 mm lens gives negatives of 106 mm ( 2 x 17 x pi) when covering 360°. With a negative height of 48 mm the vertical angle covered exceeds 100°. 4: that this length of negative makes it possible to use enlargers for the 9 x 12 cm or 4 x 5".
In the spring of 1991, I built a prototype which I first called "Rundhorisontkamera" and later renamed "Larscan" (1991) which after a few improvements gave results that were so convincing that Michel decided to do at least as well. Using the same system, he very quickly built a very
pretty camera with a 17 mm lens.
Michel Dusariez: Since 1979, I had been doing aerial photography by kite, so I came upon the idea to make an aerial photography by kite (1992 ) covering 360°. The French seaside town of Toquet was chosen for this "World's first" on the 25th April 1992. As the risk of a crash can never be totally excluded, and as the camera used could not easily have been replaced, nerves were strained during the experiment, but fortunately nothing untoward happened. As the camera for the 120 format takes up quite a lot of space, I got the idea of creating a smaller, pocket sized model. A further Rollei 35 meets the hacksaw and the vice and with a 12.5 mm lens (taken from a Kodak Disc) it gives negatives of 76 x 18 mm, an acceptable length/height ratio. (1994). This prototype comes with an accessory which makes it possible to change the rotation ratio (to compensate for the change in refraction index under water) and a submarine body which permits underwater takes of 360° at any depth. (1994).
Lars R. Larsen: It was after having seen Michel's "pocket" prototype that I decided to make something neater in a Praktica point and shoot body using the motorised film advance system of the camera itself. This lightweight camera can easily be carried by kite and with radio remote control, it gives excellent aerial photographs. Michel Dusariez: I simply had to make a further conversion. This time of an Olympus Mµ. (1994) using the original motor drive of the camera. The outside dimensions corresponding to those of the original camera making it truly pocketable.
The construction of a 360° camera which simultaneously takes the same scene from two different points (stereoscopic views) took place, first for the 35 mm format ( 1993) and finally format 120 (1994). The stereoscopic vision is reestablished with the View Magic viewer from Dimension Press of USA using the over/under system. The latest camera of the series, a camera using a Polaroid 4" x 5" film holder saw the light of the day towards the end of 1996. It makes it possible to take instantaneous 360° views with a re-useable negative.

Michel Dusariez