Graflex Users Workshop Proposal later this summer in Tonopah Nevada

[Sirius Glass]

Well I have this for transportation there

 

[abruzzi]

You're not going to be moving fast enough on that terrain to get oval wheels in a photograph, but you might get oval wheels a different way...

 

[GKC]

Now I'm wondering what one of those steam locomotives in Nevada would look like with elliptical wheels?
It might be worth a stop in Virginia City just to find out!

 

[Sirius Glass]

Now I'm wondering what one of those steam locomotives in Nevada would look like with elliptical wheels?
It might be worth a stop in Virginia City just to find out!

Then we would need to do it in the hottest part of the summer to get those steel wheels hot enough to be stretched out that much to be elliptical, right?

 

[DREW WILEY]

Sirius - Cog railways could be way way steeper. But if 4WD drive is what you decide on, bring along a wench (just have her tug the rope; it's simpler than having her yell at you for not finding anything to hook a winch to).

 

[Sirius Glass]

Sirius - Cog railways could be way way steeper. But if 4WD drive is what you decide on, bring along a wench (just have her tug the rope; it's simpler than having her yell at you for not finding anything to hook a winch to).

I always found my wench is more useful and fun than a wrench.

 

[btaylor]

Sounds like fun- haven’t had the Baby Speed out for years.

 

[DREW WILEY]

Well, guess we need to apologize to Jim Galli for wrenching his thread away, and return that wrench in case he needs it for his Model A.

 

[Sirius Glass]

Well, guess we need to apologize to Jim Galli for wrenching his thread away, and return that wrench in case he needs it for his Model A.

Metric and Whitworth tools need not apply.

 

[DREW WILEY]

Gosh, one of the earlier jobs I have in this town was selling fasteners and precision tools to machinists and all kinds of car dealerships. We actually stocked a huge selection of Whitworth, metric, even exotic metric, everything right down to special thread gunsmith taps and antique lock taps and dies. Every size English, metric, letter, and number drill you could think of. Big selection of Starrett precision tools. I knew just about every dirty little secret about import car brands. Yep, every single brand had certain engineered in weaknesses designed to dramatically improve service department income, which is exactly where dealerships made most of their money.

But out in Jim's part of the world, transportation was different. My mother's uncle was a circuit preacher in the silver boomtowns like Silver City, as well as in the beginning of little towns like Lamoille and across the border into Calif at Big Pine. I've got an album of little albumen prints of shots taken by his daughter, including a "snowplow' consisting of a log being drawn by chains and oxen at each end. That's the kind of transportation Jim would approve of. He'd no doubt love the vintage shots too.

 

[SteveinAlaska]

i knew when I got this Crown Graphic and the Elgee lens it would put me in a league of like-minded individuals that marched to the beat of a different. Now if I could convince the Canucks to let cross the border with it.

 

[jimgalli]

Not to pop anybody's bubble or anything. The Model A on the road to mud lake. I wouldn't take my wife's 2017 Nissan Altima, but it's not a bad road. Rental cars can go anywhere of course. Buy insurance.

 

[bernard_L]

This is a proposal to solve a single problem with singular equipment. I want to duplicate the "Lartigue" effect of the leaning wheels on race cars at speed only possible with graflex curtain shutters. I am limiting myself to film and shutter speeds available off the shelf in 1908 - ish.
<< snip >>
We know he was panning the moving vehicle.
View attachment 294528

OK, Lartigue was panning, and he must have been because the car is sharp and the background motion-blurred. Then I understand that the bystanders in the background are tilted backwards, because of horizontal camera motion during curtain travel. But why are the wheels tilted backwards? The car was, after all, stationary with respect to the camera frame.
Anyone with a convincing explanation?

 

[bdial]

OK, Lartigue was panning, and he must have been because the car is sharp and the background motion-blurred. Then I understand that the bystanders in the background are tilted backwards, because of horizontal camera motion during curtain travel. But why are the wheels tilted backwards? The car was, after all, stationary with respect to the camera frame.
Anyone with a convincing explanation?

My theory would be that the wheels rotational motion doesn't match the car's horizontal motion.

 

[Sirius Glass]

i knew when I got this Crown Graphic and the Elgee lens it would put me in a league of like-minded individuals that marched to the beat of a different. Now if I could convince the Canucks to let cross the border with it.

If it is the elliptical wheels you be wanting, it will not come from a Crown Graphic. It is a focal plane shutter you will be needing.

 

[Sirius Glass]

OK, Lartigue was panning, and he must have been because the car is sharp and the background motion-blurred. Then I understand that the bystanders in the background are tilted backwards, because of horizontal camera motion during curtain travel. But why are the wheels tilted backwards? The car was, after all, stationary with respect to the camera frame.
Anyone with a convincing explanation?

The people were told to lean the other way for the photograph. Siriusly, the wheels are distorted because the focal plane slit in moving down during the exposure and the image in the camera is upside down.

 

[bernard_L]

My theory would be that the wheels rotational motion doesn't match the car's horizontal motion.

"Drifting" had not been invented back then. Here is a car with wheels rotational motion not matching the car's horizontal motion:

 

[bernard_L]

Siriusly, the wheels are distorted because the focal plane slit in moving down during the exposure and the image in the camera is upside down.

This explains why the spectators appear tilted (front, back, not the issue here, just depends on the up/down slit travle direction).
As I wrote, the issue (for me) is why the wheels appear tilted at all, since clearly Lartigue was panning, and the car (body, wheels) was stationary WRT the camera's aiming direction.

One possible explanation for the left-hand picture: panning was adequate for --say-- the driver; the wheel, being closer to the camera, had faster apparent left-right motion; whence the tilt.
This does not, however, fit withe appearance of the right-hand picture. There, panning appears to be properly done (car is sharp and road completely motion-blurred). The near-side wheels, being closer to the camera, have a faster apparent angular motion; and the opposite of course for the far-side wheels; panning can match only one angular motion, presumably the car's body. So, if the explanation just given for the left-hand picture were correct, the near- and far-side wheels should have opposite tilts. They do not.

 

[GKC]

Maybe Lartigue had an early version of Photoshop?

 

[MattKing]

IIRC, the elliptical wheels are a consequence of a focal plane shutter that moves at a relatively slow speed.

 

[grat]

So, some J. Lane speed plates (ISO 25) and a Thornton-Pickard Roller-blind shutter?

Actually, that's a real question-- is the rolling shutter effect altered by the placement of the shutter relative to the film plane? ie, would a shutter-curtain behind the lens produce a stronger, or weaker, effect than a focal-plane shutter?

 

[bernard_L]

So, some J. Lane speed plates (ISO 25) and a Thornton-Pickard Roller-blind shutter?
Actually, that's a real question-- is the rolling shutter effect altered by the placement of the shutter relative to the film plane? ie, would a shutter-curtain behind the lens produce a stronger, or weaker, effect than a focal-plane shutter?

Executive summary. Behind-the-lens shutter: no slant effect, significant motion blur.
Some Explanation. With behind-the-lens shutter, at each instant during the slot travel, all parts of the image are equally exposed (except for the marginal effect of vignetting). So, motion blur for any part of the image is determined by the total slit travel time. And, because all parts of the image are exposed simultaneously they are all caught at the same instant, or rather over the same sizeable interval of time (did I mention motion blur?).
With a focal plane shutter, even if the travel takes, say 1/20s, each part of the image in (vertical) succession is exposed for, say, 1/200s; whence the slant effect.

 

[grat]

In general, I was speaking about a non-existant shutter-- if you have a curtain with a slit that's travelling across the cone of light, is the rolling shutter more pronounced if it's at the film end of the assembly, or the lens end?

But the TP shutter is still not going to equally expose the entire film plane over time. It's a large opening, but it's still going to pass from one end of the film plane to the other, exposing different parts of the film at different times. There will be one instant where the entire frame is totally exposed, but that's a short instant.

 

[jimgalli]

My theory would be that the wheels rotational motion doesn't match the car's horizontal motion.

Actually the car body is slanting forward the same amount as the wheels. Easily seen in the 2nd example. It's because of imperfect panning. He pressed the shutter button and slowed down his "pan" during the shutter's travel. As soon as we push that button the mirror shuts off our view and we decelerate because the picture taking is over. But it isn't.

Out where I worked for many years we had 3000mm telescopes looking at half frame 35mm film running at 100 frames per second. We would "track" the airplane flying along with a joystick that moved the gigantic lens azimuth and elevation. We had spotting scopes so we never lost visual during filming. In that scenario with about 1/4 of one degree angle of view and the object 7 miles away, we got astonishingly sharp images on our film. This is not that. Standing 15 feet from a car moving at 70 mph and panning with a 4X5 or 5X7 is pretty primitive by comparison.

I'm guessing that his shutter speed and film were pretty slow.

 

[DREW WILEY]

Lartigue consulted with Einstein prior to the shot, and bent the time-space interface. If only he had done it in color film, then we could have checked for Doppler shift to see if how many light years the vehicle had gone before the shutter curtain completely closed. That kind of technology is known way out in remote parts of Nevada. The aliens taught them that decades ago out in Area 51, and I learned it from a wild mustang caught out there, which I rode one summer briefly working as a cowboy.