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View Full Version : Horizon 202 -- how does the baffle behind the lens work?



Trask
04-01-2009, 03:09 PM
I can understand that after you take a picture with a 202 that the lens needs to be drawn back across the film, and therefore there must be some sort of baffle that comes between the rear lens elements and the film plane. But when I "take" a picture while watching the rear of the lens with the back open, I can't see the rear of the lens because of what I'm calling a baffle in place. My question is why that baffle isn't moving out of the way when I take the picture (admittedly with the back open and no film). I though that the engagement of the baffle might be linked to the little button that gets pressed down when the back is closed so the counter will work, but that doesn't seem to be it.

Anyone have a 202 who can take a look and tell me if the too cannot (or can) see the rear of the lens when the lens turret rotates? Any thoughts on this topic?

David Brown
04-01-2009, 03:30 PM
Will the camera take a picture?

Trask
04-01-2009, 04:44 PM
Don't know -- haven't wanted to waste some film if some can tell me that what I'm seeing (or not seeing) is normal!

Mick Fagan
04-02-2009, 06:24 AM
Trask, there is a vertical slit and what appears from memory, to be a shutter blind (so to speak).

My 202 is loaded with film so I cannot look.

Basically if you put the camera to the slow speed rotation, set the f/stop to wide open, sit in a darkened room with the camera on a tripod and facing a lighted doorway, open the back of the camera, and trip the shutter, you should be able to see a vertical slit of light traversing the round steel section of the rear of the camera from one side to the other.

If you need more help I can look at the camera over the weekend as I'm using it on Saturday morning, when I'll change film.

Mick.

Trask
04-02-2009, 02:26 PM
Mick - I tried it, and...nothing. No light coming through because of what appears to be a solid cover within the rectangular cutout of the drum. I think if I ran a roll through it, I'd get a whole lot of nothing.

Mick Fagan
04-03-2009, 04:41 AM
Trask, right I now have finished the roll of film in my 202.

Set the camera rotation speed to the yellow or slow rotation.

Set the bottom slightly longer lever out the front to 1/60 speed, aperture doesn't matter.

Click the shutter, you should see a very slow rotation happen, also you should see that the shutter blind is drawn and you can see through to the lens.

As you re-wind you will not see the lens as the shutter is drawn over and you will see a darker black which is slightly recessed, this is the shutter blind.

Get back to us.

Mick.

Trask
04-03-2009, 04:17 PM
Ahhh, that's what I needed to know. The shutter blind is not retracting. Your experience is the proof. I'd thought that there might be some sort of interlock (as with the standard film counter in many cameras) that meant the blind would only retract when the back was closed, but apparently not. Guess I'll have to figure out where I can get this repaired. Thanks very much.

AgX
04-03-2009, 06:21 PM
By the way, how would you call this mechanism?
"Covered Cocking"?

MickH
04-06-2009, 04:42 PM
Hi,

I've seen it refered to as

"Shutter focal plane, rotating slit, gives 1/250 s, 1/125 s, 1/60s, 1/8 s, 1/4 s and 1/2 s"

If you haven't seen Alfred's Page, you're missing lot's of insight and opinion too.

http://cameras.alfredklomp.com/horizon202/index.htm

If it's not on Alfred's page, it hasn't been written! ;)

AgX
04-06-2009, 06:21 PM
Mick,

That there is a relative movement between the slit and the film, may the film move and the whole camera rotate, or the camera and film stand still and the lens swings, is part of the game for panoramic cameras beyond 110.

But as the slit has passed the film in a swing-lens camera, the lens either has to make a further 220 turn or swing back to be ready for the next exposure. During this movement the slit has to be covered. This is similar to cocking a common focal plane shutter where the slit between the curtains has to be closed or covered.

An alternative way would be to stop a swing lens after exposure just off the film, thus blocking the slit. Then advance the film, and expose by means of swinging back to the initial position. Again stopping just off the film.

Mick Fagan
04-07-2009, 08:05 AM
AgX, I agree with you, but others may not quite understand.

The Horizon 202 should show an open shutter when the shutter has been cocked and you press the shutter button.

Without film in the camera and on the slow rotation speed, you should be able to see the blind drawn and look through to see the lens.

Simple really, not Majic :D

Mick.

MickH
04-07-2009, 11:41 AM
Terrible quality, I just did this (http://s169.photobucket.com/albums/u219/MickH56/Public/?action=view&current=05SecF28.flv) in the back garden, but you'll get the idea how it should work.

Mick Fagan
04-08-2009, 02:40 AM
Mick, brilliant, that is exactly what I see.

Mick.

Trask
04-08-2009, 04:02 PM
Yes, that's very instructive, because it's exactly what I don't see. So off the camera goes to a tech for repair. I'm halfway to believing that I screwed up the internal mechanism by changing from the slow to high shutter speeds (or vice versa) when the shutter was uncocked. The manual doesn't say you shouldn't, but one of the websites noted earlier makes that point not too.

AgX
04-09-2009, 06:20 AM
An alternative way would be to stop a swing lens after exposure just off the film, thus blocking the slit. Then advance the film, and expose by means of swinging back to the initial position. Again stopping just off the film.

This would make a baffle obsolete, but at the same time the controlled swing mechanism (shutter) would need an additional revesing device.

On the other hand such a baffle, if designed as a coaxial plane as done here, enables to get an additional feature, namely control of slit-width and thus another means of controlling exposure time.

MickH
04-10-2009, 03:34 AM
This would make a baffle obsolete, but at the same time the controlled swing mechanism (shutter) would need an additional revesing device.

On the other hand such a baffle, if designed as a coaxial plane as done here, enables to get an additional feature, namely control of slit-width and thus another means of controlling exposure time.

The Horizon, (and Widelux and Noblex as far as I can tell) already use variation in slit width to control exposure. On the Horizon the lens barrel only rotates at two speeds, controlling the High and Low exposure timings. Slit width is set by the Aperture control lever thus varying the amount of time the film surface is exposed to light as the barrel rotates. At the end of each exposure the slit closes completely (with an audible click) which prevents the film becoming exposed when the shutter is cocked, the film wound forward, the lens barrell returned to it's starting point and the spring re-tensioned.

I'm pretty sure that introducing a "reverse swing" element would make these cameras even more expensive and complicated. And, as for the Horizon, make the beast less reliable.

RobertV
04-10-2009, 03:56 PM
You can better take pictures instead of understanding those difficult way how the camera is working ;)

http://farm1.static.flickr.com/73/177074900_d616afb152.jpg

Best regards,

Robert

europanorama
07-07-2009, 12:12 AM
The Horizon, (and Widelux and Noblex as far as I can tell) already use variation in slit width to control exposure. On the Horizon the lens barrel only rotates at two speeds, controlling the High and Low exposure timings. Slit width is set by the Aperture control lever thus varying the amount of time the film surface is exposed to light as the barrel rotates. At the end of each exposure the slit closes completely (with an audible click) which prevents the film becoming exposed when the shutter is cocked, the film wound forward, the lens barrell returned to it's starting point and the spring re-tensioned.

I'm pretty sure that introducing a "reverse swing" element would make these cameras even more expensive and complicated. And, as for the Horizon, make the beast less reliable.
Slit width is set by the Aperture control lever
WRONG-WRONG-WRONG
slit width is controlled by the time(exposure)-control lever
aperture is controlled by the aperture control lever.
the problem is that the screw which holds the door-opener can get loose. thats why it should be fixed/treated with locktite(half-strong). the position of that door-opener must be adjusted so one can get the full image-size of 58mm lenght. mine got loose during shelf storage!
lets hope that promised digital horizon will be of topquality.

MickH
07-07-2009, 05:11 AM
WRONG-WRONG-WRONG

My word, you jump in with both feet when you correct someone don't you.

europanorama
07-27-2013, 05:02 AM
The Horizon, (and Widelux and Noblex as far as I can tell) already use variation in slit width to control exposure. On the Horizon the lens barrel only rotates at two speeds, controlling the High and Low exposure timings. Slit width is set by the Aperture control lever thus varying the amount of time the film surface is exposed to light as the barrel rotates. At the end of each exposure the slit closes completely (with an audible click) which prevents the film becoming exposed when the shutter is cocked, the film wound forward, the lens barrell returned to it's starting point and the spring re-tensioned.

I'm pretty sure that introducing a "reverse swing" element would make these cameras even more expensive and complicated. And, as for the Horizon, make the beast less reliable.

the aperture lever closes the aperture and the exposure-time lever changes slit widths(3 for the horizon 202, 4 for the old horizon).
I know both cameras by heart but i am no repairman. i am the owner of the delphi-forums-rotating panoramic camera-forum.
im my opinion some important screws need loctite to be used. attention: there are special-screws(with two holes which rotate the opposite way. a special opening tool is needed.
my ho 202 had been rebuild by my repairman here, also widelux 1500-expert. in rangefinderforum i have given detailed instructions how to increase DOF(by changing distance lens to film)