8mm Forum: Throw distances?

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Topic: Throw distances?

Michael O'Regan
Film God

Posts: 3085
From: Essex, UK
Registered: Oct 2007

posted March 05, 2009 04:05 AM

I'm wondering at what distances a good picture can be got with the average 8mm projector.

I have a 22ft throw distance with 16mm and wonder if this would be too far back for a bright picture with the lamps used generally in S8 projectors.

I realise there are different lamps involved and I would exclude Xenon.

-Mike

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted March 05, 2009 06:36 AM

It should by fine, I project at about 20 feet on a screen 52" tall with 100W lamps all the time and it looks good. Obviously 150W lamps and more would be even brighter.

I've backed up another 5 to 10 feet and the only difference is it starts to be a long walk back to the machine to change reels and adjust focus! (It's two rooms away from the screen as well.)

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All I ask is a wide screen and a projector to light her by...

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Graham Ritchie
Film God

Posts: 4001
From: New Zealand
Registered: Feb 2006

posted March 05, 2009 12:39 PM

I have both Super8 and B/H 16mm "40mm lens" side by side at a distance of 7.5 meters I think thats around 23feet giving a projected screen width of about 65inches. The brightness of the Super8 ST180 12V/100watt is very good as with the ST1200 with the 15V/150watt both are much brighter than the GS1200 fitted with a 24V/200watt EJL lamp that many still use. Super8 can give a bright picture but to be up there with 16mm needs the right lens, shutter, and lamp, what Super8 projector are you using?

Graham.

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Osi Osgood
Film God

Posts: 10204
From: Mountian Home, ID.
Registered: Jul 2005

posted March 05, 2009 01:41 PM

A good sized midget can be thrown about six feet!

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"All these moments will be lost in time, just like ... tears, in the rain. "

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Michael O'Regan
Film God

Posts: 3085
From: Essex, UK
Registered: Oct 2007

posted March 05, 2009 01:43 PM

I don't have a S8 projector.

I only collect 16mm at the moment.

-Mike

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted March 05, 2009 02:01 PM

Something weird that can happen when Super-8 is shown on an extremely long throw has nothing to do with the picture. Because of the short separation of sound and picture Super-8 sometimes will have problems with 24 Hz flutter on the audio output because the machine can't completely smooth the motion of the film between the gate and the sound head.

The sound of the machine masks this, but when you move the machine away and can't hear it, the flutter comes through the speakers.

I had idea of putting my machines on the back porch and shining them on my living room screen almost 30 feet away: kind of a poor man's projection booth. This problem pretty much ended that idea.

This must not always be the case, after all there are long throw lenses for Super-8; somebody had to make this work!

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All I ask is a wide screen and a projector to light her by...

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Michael O'Regan
Film God

Posts: 3085
From: Essex, UK
Registered: Oct 2007

posted March 05, 2009 02:30 PM

Hmmmm....that's interesting.

Anybody else come across this problem that Steve mentions?

-Mike

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted March 05, 2009 03:18 PM

Oh yeah,

I started a thread about it at the time:

http://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=002888

Kind of a shame they didn't keep R8's longer separation between image and sound, it would probably have helped a lot, but maybe the closer separation made the Super-8 sound camera cartridge geometry work out better.

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All I ask is a wide screen and a projector to light her by...

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Michael O'Regan
Film God

Posts: 3085
From: Essex, UK
Registered: Oct 2007

posted March 05, 2009 04:23 PM

It sounds like a bit of a nuisance from reading that old thread.

I'm always toying with the idea of getting into S8 but, things like this are a little offputting.

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted March 05, 2009 04:52 PM

I have the exact opposite temptation, but stick with S8 because it performs very well within the set of limits I use it in and it's easy to live with.

The various gauges are meant for specific purposes. The bigger the gauge, the more the capability. The smaller the gauge, the greater portability, space efficiency and lower cost.

You don't haul concrete in a VW beetle and you don't go grocery shopping with a 20 ton dump truck. Neither is a match for the job at hand.

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All I ask is a wide screen and a projector to light her by...

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Graham Ritchie
Film God

Posts: 4001
From: New Zealand
Registered: Feb 2006

posted March 05, 2009 05:09 PM

Hi Steve
Thats interesting, I have been projecting Super8 for over 30 years and never noticed a problem with the ST1200M and later the GS1200 "later model" as you discribe with the sound. It might be I have just never picked up on it, if and when it does occur. The projection box I now use completely isolates all projector noise "less the better" which greatly improves watching a movie.

Graham. [Smile]

PS. Michael I would not be put of getting into Super8 for all its faults its a lot of fun and with plenty of film still around like from Derann its well worth it.

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Joe Taffis
Phenomenal Film Handler

Posts: 1592
From: United States
Registered: Jun 2003

posted March 05, 2009 05:12 PM

Although i've never used one, i'm told the rare ELMO f1.2 long throw lense solves this problem of throwing an image from the back of a big room or hall for the ELMO super 8 projectors. I don't know if there are similar lenses for other makes.

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Joe Taffis

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted March 05, 2009 05:20 PM

It's not a constant problem, and as I understand it projectors with a pinch roller between the gate and heads have it less often.

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All I ask is a wide screen and a projector to light her by...

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Graham Ritchie
Film God

Posts: 4001
From: New Zealand
Registered: Feb 2006

posted March 05, 2009 05:26 PM

The long throw lens I use is the Elmo F:1.4, 25-50mm lens its nice and sharp and will fit any Elmo projector.

Graham.

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