8mm Forum: Newer Acetate focus problems

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Topic: Newer Acetate focus problems

Chip Gelmini
Phenomenal Film Handler

Posts: 1733
From: Brooksville, FL
Registered: Jun 2003

posted February 22, 2006 05:16 PM

I have been collecting super 8 for a very long time. I have run acetate and polyester for so long, it is difficult for me to solve this new problem.

Can anyone tell me why, newer select prints of acetate with sound striping are running out of focus? The given problem....when spliced to polyester, major focus adjustments are required.

WHY?

These prints I have aquired from Steve Osborne and I believe they are from CHC in Cleethorpes.

They are:

Rupert & The Frog Song
Mr. Bean Goes to a Premiere
Chubb Chubbs
Various Dolby Stereo Snipes

Even after multi runnings and 3 Filmguard screenings I am having this problem. Any information would be greatly appreciated. The pressure springs on the front gate of the Elmo ST1200HD that I use seem to be just fine. Older acetate prints from years ago are not giving trouble.

Thanks in advance.

Chip

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Adrian Winchester
Film God

Posts: 2941
From: Croydon, London, UK
Registered: Aug 2004

posted February 22, 2006 06:20 PM

I've always thought that this was liable to be a problem, if you splice the two together, because I believe polyester stock is usually thinner. So I'm more surprised that you have not found the same thing with your older acetate films.

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Adrian Winchester

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Michael De Angelis
Phenomenal Film Handler

Posts: 1261
From: USA
Registered: Jul 2003

posted February 22, 2006 07:10 PM

Chip,

As you know, there are many variables to take into consideration.

I do not have any prints from CHC, but I always need to
touch up the focus between prints.

It's not what you have failed to do with film treatment, it's
only that the stocks are different, and a slight touch up
on the focus is due between the different stocks.

Have you changed the lens on your setup?
A faster lens, will make this incident more noticeable between stocks.

Some lenses such as the Elmo 1.0 lens, has less depth of field.
It is more difficult to keep films in focus.

But it seems that the newer stock that CHC is using is
different than what you may have been accustomed to using in the past.

I have also found the longer or warmer the lamp is running will also affect the focus.

I don't know if this answers your questions, but I hope it was helpful.

Michael

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Isn't it great that we can all communicate about this great
hobby that we love!

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

posted February 23, 2006 01:22 AM

Polyester stock is thinner than Acetate and also most poly stock had laminated stripe I believe? The films coming form Dearann and CHC have paste stripe whcich is probably thicker. The stripe is on the base of the film which sits against the fixed film gate so any variations in stripe thickness along with film thicknes will shift the focus.
This is why Noris and one or two others had the fixed part of the gate on the lens side so that the emulsion side was allways the same distance from the lens. Variations in thickness wont show up in that arrangement.
Earlier Poly and Acetate print stocks were the same thickness.
Todays Acetate stock is thinner than the earlier stocks I know that contradicts what I said at the start but the spec of film has changed over the years.

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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John Clancy
Phenomenal Film Handler

Posts: 1954
From: Cornwall
Registered: Jun 2003

posted February 23, 2006 05:42 AM

Kev, the present acetate prints coming from CHC have laminated stripe applied at the lab. That is possibly what makes the stock appear thicker than acetate stock from years ago.

--------------------
British Film Collectors Convention home page www.bfcc.biz. The site is for the whole of the film collecting hobby and not just the BFCC.

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

posted February 23, 2006 07:46 AM

I think it is probably down to stripe thickness. Yes I forgot that Derann arent applying the stripe to CHC's prints now. Thinking about it Derann have been applying paste stripe to all their poly prints.
If the CHC laminate stripe is thicker then that would give the prob that Chip has mentioned.
Chip, it looks like you will have to stay close to those focus controls.

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Chip Gelmini
Phenomenal Film Handler

Posts: 1733
From: Brooksville, FL
Registered: Jun 2003

posted February 24, 2006 11:32 AM

Thanks guys for your inputs. Somehow, I expected to read Kevin's final comments about this. It's just a bummer, because I run with two machines and I've taken the time to buy 3 reels of Dolby snipes, cut them up and insert at the ends of short reels and/or on the front of feature reels. Imagine a quick focus adjustment just seconds before changeover, then back again between formats and big reels!

I really like the Dolby snipes. I've been using them sort of, as feature presentation snipes. My other complaint about them is they are not stereo sound on super 8. I understand CHC does not have stereo dubbing equipment, so that's OK, but still alittle dissapointing. By the way for those of you who don't have these buggers, they are great graphics and look positively stunning in scope. You get five prints on one reel, 2 scope and 3 flat. Between formats there are duplicate graphics, but all 5 screened there are atleast several different versions. My personal favorite the very last one, flat, that has a helicopter flying through downtown, and the word Dolby is built into the theater's building design.

CG

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James N. Savage 3
Phenomenal Film Handler

Posts: 1375
From: Washington, DC
Registered: Jul 2003

posted February 25, 2006 11:21 AM

Chip- I purchased the helecoptor dolby clip on another reel a few years back and had Robert Aragon re-record it to stereo- now it sounds a-m-a-z-i-n-g! Check with Robert to see if he's still re-recording.

Nick.

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Mark Norton
Master Film Handler

Posts: 330
From: Hampton Hill, Middlesex, U.K.
Registered: Feb 2004

posted March 02, 2006 10:23 AM

I have this reel too.The Dolby steam train is my favourite but it is the mono sound that lets it down. I have managed to re-record the "Helecopter" one from video and this is now the business with sound comming from the surround speakers.
Does anybody know where to sorce the sound for re-recording the others? Also I seem to have the same focusing problem with these.

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