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Test shot for an old lens taken from a 6x9 camera and mounted on a lens board.
Time exposure of 20 seconds at f/11.3
IN ENGLISH BELOW THE LINE
La Ansco Memo fou la primera càmera nord-americana de format 35mm produida en grans quantitats. És per tant, contemporania a les primeres Leica, i alhora amb un mecanisme completament diferent. De fet és una de les poques càmeres de format 35mm amb el funcionament i disposició verticals. La Kodak 00 Cartrige Premo és anterior, però no emprava rodet del format 135 (amb perforacions), sino 35 (llis i amb paper al dors). Indicador de ser una camera molt antiga, el cos encara està fabricat en fusta coberta de cuiro.
És una càmera d'obturador central (Wollensak Deltax No.0), amb visor situat sobre el cos de la càmera, disparador en un lateral, i el sistema d'avenç de la pel·licula, a la part posterior. A mi em fa pensar més en un llum d'oli que en una càmera. Per diverses caracteristiques concretes, aquesta càmera sembla datar del 1929-1930. Per desgracia l'obturador no funciona, però si altres mecanismes de la càmera.
camera-wiki.org/wiki/Ansco_Memo
========================
The Ansco Memo was the first American 35mm format camera produced in large quantities, from 1927 till 1931. It is therefore contemporary to the first Leicas, and at the same time with a completely different mechanism. In fact it is one of the few 35mm format cameras with vertical operation and layout. The Kodak 00 Cartrige Premo was earlier, but did not use format 135 film (with perforations), but 35 (smooth and with paper on the back). Oh, and it's a half-frame camera, producing a negative half the size of a standard 35mm machine. The body of the camera si made of wood.
It is a leaf shutter camera (Wollensak Deltax No.0), with a viewfinder located on top of the body of the camera, a trigger on the side, and the advance system of the film, on the back. It makes me think more about an oil lamp than in a camera. For several specific features, this camera seems to date from 1929-1930. Sadly, the shutter does not work.
camera-wiki.org/wiki/Ansco_Memo
www.vintagephoto.tv/anscomemo.shtml
Atelier Ying, Chinatown, Nyc.
Falcon Super Action Candid Model F
with 50mm Wollensak lens and Deltax shutter
This was $42, my most expensive vintage gear, but it's a birthday present..:)
I can think of at least 4 ways to modify this for modern "VIntage-matic" use:
1. unscrew the lens and shutter and mount it to a homemade camera (this camera is one of the few that can do it, it's so versatile!)
2. drill a hole in the back (not, as the back is in too nice a condition for that)
3. make a substitute back with a hole in it, which means I can decorate the back, nice...
4. use just the lens in another DIY project. Not, as I don't like the M4/3 style.
5. convert it from 127 to use a modern film (should be not much of a problem but it will leave sprocket holes in the final developed images - the Lomo style, I might do this even with a digital
modification as it won't interfere with the digital. Versatile!
6. buy special (expensive) 127 film and use it (my 1st choice as the wollensak is too nice in this and the special shutter is a feature I am very curious about.
However, the golden money envelope is a present from a friend..:)
Keukenhof 26-04-2022. Deltax Tours, Delft (NL) BZ-VT-84 (504), Scania KEB6X2*4 / Beulas Stergo' Spica new in April 2012.
IN ENGLISH BELOW THE LINE
La Ansco Memo és una de les primeres càmeres de 35mm, contemporanea amb la famosa Leica, i de fet la primera americana en aquest format. Però tot i la seva originalitat, és una càmera poc eficient, comparada amb la meravella fabricada a Wetzlar.
En aquest cas, el petit obturador Wollensak Deltax no acaba de funcionar be, i tot i desmontar-lo en bona part, no he reeixit en fer-lo funcionar.
camera-wiki.org/wiki/Ansco_Memo
====================
The Ansco Memo is one of the first 35mm cameras, contemporary with the famous Leica, and in fact the first American one in this format. But despite its originality, it is an inefficient camera, compared to the wonder made in Wetzlar.
In this case, the small Wollensak Deltax shutter doesn’t work, and despite disassembling it in large part, I didn’t succeed in getting it to take pictures.
IN ENGLISH BELOW THE LINE
El sistema d'avançar la pel·licula és força inusual en aquesta Ansco Memo. En comptes de la típica rodeta dentada, té dos "ganxos" que estiren la pel·licula cap avall i després retornen a la posició inicial apartats ja d'aquesta.
La Ansco Memo fou la primera càmera nord-americana de format 35mm produida en grans quantitats. És per tant, contemporania a les primeres Leica, i alhora amb un mecanisme completament diferent. De fet és una de les poques càmeres de format 35mm amb el funcionament i disposició verticals. La Kodak 00 Cartrige Premo és anterior, però no emprava rodet del format 135 (amb perforacions), sino 35 (llis i amb paper al dors). Indicador de ser una camera molt antiga, el cos encara està fabricat en fusta coberta de cuiro.
És una càmera d'obturador central (Wollensak Deltax No.0), amb visor situat sobre el cos de la càmera, disparador en un lateral, i el sistema d'avenç de la pel·licula, a la part posterior. A mi em fa pensar més en un llum d'oli que en una càmera. Per diverses caracteristiques concretes, aquesta càmera sembla datar del 1929-1930. Per desgracia l'obturador no funciona, però si altres mecanismes de la càmera.
camera-wiki.org/wiki/Ansco_Memo
========================
The film advance of the Ansco Memo is quite inusual, as it has no sprockets. The film is displaced by a pair of claws that grab it and pull it downwards, and then disengage when returning to position.
The Ansco Memo was the first American 35mm format camera produced in large quantities, from 1927 till 1931. It is therefore contemporary to the first Leicas, and at the same time with a completely different mechanism. In fact it is one of the few 35mm format cameras with vertical operation and layout. The Kodak 00 Cartrige Premo was earlier, but did not use format 135 film (with perforations), but 35 (smooth and with paper on the back). Oh, and it's a half-frame camera, producing a negative half the size of a standard 35mm machine. The body of the camera si made of wood.
It is a leaf shutter camera (Wollensak Deltax No.0), with a viewfinder located on top of the body of the camera, a trigger on the side, and the advance system of the film, on the back. It makes me think more about an oil lamp than in a camera. For several specific features, this camera seems to date from 1929-1930. Sadly, the shutter does not work.
camera-wiki.org/wiki/Ansco_Memo
www.vintagephoto.tv/anscomemo.shtml
IN ENGLISH BELOW THE LINE
La Ansco Memo és una de les primeres càmeres de 35mm, contemporanea amb la famosa Leica, i de fet la primera americana en aquest format. Però tot i la seva originalitat, és una càmera poc eficient, comparada amb la meravella fabricada a Wetzlar.
En aquest cas, el petit obturador Wollensak Deltax no acaba de funcionar be, i tot i desmontar-lo en bona part, no he reeixit en fer-lo funcionar.
camera-wiki.org/wiki/Ansco_Memo
====================
The Ansco Memo is one of the first 35mm cameras, contemporary with the famous Leica, and in fact the first American one in this format. But despite its originality, it is an inefficient camera, compared to the wonder made in Wetzlar.
In this case, the small Wollensak Deltax shutter doesn’t work, and despite disassembling it in large part, I didn’t succeed in getting it to take pictures.
Here is the Falcon (model F) camera built by Utility Manufacturing in Rochester, NY. from 1938 to 1941. The F/3.5 lens and the Deltax self-cocking shutter (time, bulb, 1/25, 1/50 and 1/100 second) were both made by Wollensak. It takes 3/4 sized photos on 127 rollfilm; so 16 3x4cm photos (as opposed to 12 4x4cm photos on most 127 cameras).
There is a fairly large mechanism on the back to see the exposure number on the back of the camera that lets in some light and the shutter on this particular camera is only reliable at 1/100.
I purchased this camera for $12 + shipping on ebay.
Pictures I have taken with this camera can be seen here:
www.flickr.com/photos/vintagejohn/albums/72157660833984261
Details on this photograph:
Camera: Ansco Speedex 4.5 Special (circa 1951-53)
(a rebadged Agfa Isolette II)
Film: FomaPan 200
Aperture: F/12.5
Shutter Speed: 1/5
Distance to Subject: 15"
Other: Used Kodak "Porta 2+" supplementary close-up lens
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Keukenhof 13-05-2017. Deltax, Delft (NL) BT-SV-52 (520), IVECO 395E.10.30 Midirider / Marcopolo Viaggio 350 new 02/2008.
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Manufactured by Utility Manufacturing Company New York, USA
Model: c.1940 Model F, produced from c.1938
Medium format film Viewfinder camera; film 127 roll, picture size 3x4cm with 16 exposures
Lens: Velostigmat 2 inch f/3.5 (Wollensak Optical Company, Rochester,USA)
Aperture: up to f/22setting: lever and scale on the lens-shutter barrel
Focus range: 4-25 feet +inf
Focusing: helicoid focusing, the focus locks at every distance mark that is engraved in the focusing ring. In order to turn the focusing ring it is necessary to push down and hold the small chrome button that is located on the side of the lens mount
Shutter: (Wollensak) Deltax, everset shutter, (self-cocking),
speeds: 1/25-1/50-1/100 +B, setting: lever and scale on the lens-shutter barrel
Cocking lever and Shutter release: by the same lever, on the lens-shutter barrel
Cable release socket: on the lens-shutter barrel
Viewfinder: simple eye-level reverse telescopic optical viewfinder
Winding knob: on the top plate
Flash PC socket: none
Cold-shoe
Self-timer: none
Back cover: remeovable, opens by a latch on the right side of the camera, w/ Two red windows and built-in lid
Filmloading: special spool mechanism
Tripod socket: ¼"
Camera leg: retractable, below the lens mount.
Strap lugs
Body: Neilite (similar to Bakelite), and helical lens mount, and back cover heavy cast-metal; Weight: 540g
serial no. none
More info: McKeown’s 12th ed. p.943
Here is the second of the two prototypes of a spring wound clockwork motor driven 828 film cameras I purchased many years ago. This is the more advanced one, having interchangeable shutter/lenses, an exposure counter, a focus mount, as well as a removable viewfinder. This one sports a 2" Wollensak f3.5 Velostigmat lens in a Deltax No. 1 shutter. I believe they were made in the mid to late 1930's. It's interesting that the film counter goes up to 16 when the film was originally made for 8 exposures.
I am trying to research these cameras and welcome any input you may have as to their origin or similarities to other vintage cameras of the era.
I have now found out that my prototype cameras are actually prototypes of the Bell and Howell FOTON made by a Louis H. Moomaw.
Sky the dog, who has just been bathed, hence the wet look, in the non ferrous shop stripping copper earth cable with her teeth. She usually runs off with it and adds it to her collection of "toys"
Sky the dog, who has just been bathed, hence the wet look, in the non ferrous shop stripping copper earth cable with her teeth. She usually runs off with it and adds it to her collection of "toys"
Sky the dog, who has just been bathed, hence the wet look, in the non ferrous shop stripping copper earth cable with her teeth. She usually runs off with it and adds it to her collection of "toys"
Utility MFG Co. (New York, USA)
12,8 x 7,8 x 6,8 cm
Film 127 (3,0 X 4,0 cm)
Shuter: Deltax shutter T, B, 1/25, 1/50, 1/100
Lens: Wollensak Velostigmat f/4.5 4.5, 5.6, 8, 11, 16, 22
Focus: Fucosing lens
(McKeown's 12e p 943)
(Ull màgic nº 217)
Sky the dog, who has just been bathed, hence the wet look, in the non ferrous shop stripping copper earth cable with her teeth. She usually runs off with it and adds it to her collection of "toys"
Proyecto Deltax, Diseño de Objetos y Ambientes. Realizado por José Arias y Silvia Vicencio, estudiantes Inacap.
Foto: Emol.com
This slide discusses average velocity versus instantaneous velocity. The green (x2-x1)/(t2-t1) calculation is the average velocity across the entire part of the parabola shown. There other lines that touch in increasingly closer together points. Finally, at the limit where the two points are basically on top of each other, when the change in time between them has approached zero, we are essentially at a tangent line. This is called the derivative of the function at that point in time. To symbolize that we've gotten to the tangent line situation, where the line used in calculating slope is only touching the graph once, we change deltax/deltat to dx/dt.
appareil rentrant dans les miniatures fabriqué aux USA en 1938. Le viseur est externe et la mise au point se ait par rampe hélicoïdale de 4 pieds à l'infini. L'objectif est un Vollensak & Inoh velostigmate 4,5/50mm et l'obturateur central Deltax (25.50et 100) plus poses B et T. Le diaphragme à iris ouvre de 4,5 à 22. La pellicule est une 127 en 30x40 pour 16 vues et avance avec une molette. L'arrière et le bloc objectif sont en métal et le corps en bakélite noire. L'appareil est lourd ; 530g pour des dimensions modestes : 130x75x55 fermé et 70 objectif déployé. un petit pied dépliant permet de maintenir l'appareil posé d'aplomb.
This slide shows how to take a (t,v) graph and convert it back into a (t,x) graph. First, one finds the area under the curve in a given time segment. For example, on this graph, there is a change in the curve at 10 seconds, 20 seconds, 30 seconds, and 40 seconds. The time limits are therefore 0-10, 10-20, 20-30, etc. The upper and lower bounds in each segment are the curve and the t-axis. Thus, the areas in question are the boxes on the center graph. It is important to recognize that these represent displacement, deltaX, and not position, X. Math can't help you find position from displacement if you don't know your starting position. Look at the two graphs on the right. The (t,v) graph shows a constant velocity of 3 m/s. Which of the (t,x) graphs generated it? The red, the blue, or the green? We don't know. All have a slope of 3 m/s. If I dropped you off in the middle of nowhere on the side of a highway and had you walk 5 miles north, you wouldn't know where you are. You'd be 5 miles north of somewhere you don't know where it is. So someone has to TELL you your starting position, x0. In the table, I specified it as 17 meters. I did that randomly. Notice from the second row of the table downward, I filled in the area of each segment of the curve, delta x. The new position in each row, x, is obtained by adding deltax to whatever x came before it. Hence 50+17=67, 67-30=37, etc. If you think of the table as a checkbook, deltax is a deposit or withdrawal, and x is the balance.
This is a nice question about Hooke's Law. At the lower left, we see a black spring, and then a maroon compressed version and a green extended version. Note that either compression or extension can be deltaX. The problem shows using free body diagrams and sum of force equations to determine things about the spring. Note that the - sign is missing from the spring force because the free body diagram already determined its direction.
Robert Hooke discovered something that might seem obvious: if you stretch (or compress) a spring more, it resists more. That's a positive trend that you'd expect since you played with your first pogostick. But what's interesting is the shape of the graph. In this lab, we discover that for many springs, the relationship is linear. hence the equation F=k(deltax). the spring constant, k, is a measure of the spring's stiffness. Unlike other laws you've seen, Hooke's law isn't really a law. It's just true for a lot of springs. We can't assume it's true unless a.) we check by making a graph like this or b.) you're told it's an "ideal" spring. Note there's usually a negative sign put in front. This sometimes confuses students. It's just there to remind you that F and deltax are in opposite directions. If you squash a spring in, it pushes out. If you yank it out, it pulls back in. The negative NEVER goes into sum of force equations (you've already determined direction with your free body diagram.)
This is an open-ended lab where students need to find the relationship between F and deltax, the spring force and the spring displacement. The students are given three springs and they're going to make a graph like in this slide for each of the three springs. The graph will consist of different spring forces (caused by different weights hanging on them at equilibrium) and measuring the effect on how the spring stretches. We'll use the graph to come up with the spring equation.
Appareil folding fabriqué aux USA de 1923 à 1927 de n° 47294. Viseur optique basculant, objectif achromatique f : 8, obturateur rotatif Wollensak Deltax n° 0 T B 100 50 25. Ouvertures iris de 8 à 64 et mise au point sur rail de 2 à 30 m et infini.. Film 120. Prise déclencheur souple, 2 écrous de pied, soufflet noir de 10 plis et 390 g. 31 x 73 x 170 mm. Poignée marquée Ansco et marquage sur socle en intérieur.
Here is the Falcon (model F) camera built by Utility Manufacturing in Rochester, NY. from 1938 to 1941. The F/3.5 lens and the Deltax self-cocking shutter (time, bulb, 1/25, 1/50 and 1/100 second) were both made by Wollensak. It takes 3/4 sized photos on 127 rollfilm; so 16 3x4cm photos (as opposed to 12 4x4cm photos on most 127 cameras).
There is a fairly large mechanism on the back to see the exposure number on the back of the camera that lets in some light and the shutter on this particular camera is only reliable at 1/100.
I purchased this camera for $12 + shipping on ebay.
Pictures I have taken with this camera can be seen here:
www.flickr.com/photos/vintagejohn/albums/72157660833984261
Details on this photograph:
Camera: Ansco Speedex 4.5 Special (circa 1951-53)
(a rebadged Agfa Isolette II)
Film: FomaPan 200
Aperture: F/12.5
Shutter Speed: 1/5
Distance to Subject: 15"
Other: Used Kodak "Porta 2+" supplementary close-up lens
Math is a simple black and white: You either get the correct answer or the wrong one.
Perhaps that's why I enjoy it so much.
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It was really awkward trying to take this picture. Thank you, Ms. Sciacca, for understanding.
***Constructive criticism is highly appreciated!***
3 cameras here! Using the Lumix(reflected in the strap stud) looking through the viewfinder of the old Agfa Synchro Box camera (c.1950's), at the even older (c.1913) Harrington's Deltax No.0 camera in afternoon light. The oldies are still in perfect working order.