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Topic: Jumpy picture chinon 7500MV help

Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 10, 2013 05:44 AM

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Hi all,i've got the chinon 7500MV and i've heard they have a soft filmgate tension which makes most of my films have a picture that is unsteady - it is like i am moving the framer up and down like a bouncy picture.
Anybody had this and made the picture more steady?
Cheers

--------------------
Cheers from me in New Zealand :-)

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Michael Wright
Expert Film Handler

Posts: 184
From: Chorley, Lancashire, England
Registered: Dec 2008

posted March 11, 2013 04:00 AM

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Hi the first thing I would try is Filmguard to lubricate the film. MIKE

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Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 12, 2013 05:59 PM

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Thanks Mike, ordered some filmguard from the States today,not cheap but i've read good things about it.....will see what happens [Smile]

[Smile]

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Cheers from me in New Zealand :-)

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Jon Addams
Jedi Master Film Handler

Posts: 638
From: New York, NY, USA
Registered: Apr 2007

posted March 12, 2013 09:03 PM

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Hello Clinton,

Your projector appears not to be holding the loops. You may have a claw penetration problem and may need to adjust it just a bit. You will need an Allen wrench to get the job done.

Loosen the grub screws (2) in the shutter hub and slide it forward just a tiny bit at a time, testing it as you go. You may need to repeat the procedure until you get it in the right position.

If the pin is not broken, this will fix the problem in better than 90% of the time.

Good luck,

Jon

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Clinton Hunt
Jedi Master Film Handler

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From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 17, 2013 06:39 AM

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Hi Jon,
Thanks for the help. Before I attempt it I want to make sure it is that problem or does it need to rack-up a few hours running? As it is in new condition and the owner only used it about a dozen times. Did you have this type of projector and fixed it?
Thanks, Clinton

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Cheers from me in New Zealand :-)

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David Kilderry
Jedi Master Film Handler

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From: Melbourne, Victoria, Australia
Registered: Feb 2006

posted March 17, 2013 09:35 PM

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It would be the pressure plate. If you can put some gentel pressure on the sprung gate when it is jumping that will tell you. The springs give way over time and is also a problem in various Sankyo, Eumig and other projectors. Film Guard helps, but some prints will still jump you will find.

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frank arnstein
Jedi Master Film Handler

Posts: 534
From: Gold Coast. Australia
Registered: Jan 2005

posted March 18, 2013 08:31 AM

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Hi Clinton,
I agree with Jon on solving this problem.
Not enough claw penetration is usually the cause of this symptom. If the claw is adjusted correctly, very little pressure on the film is required from the pressure plate. The main force on the film is downwards as its pulled down by the claw finger. If the penetration depth is correct then it won't slip out of the film hole, even with minimal pressure from the pressure plate.
The same thing applies to the Eumigs and Sankyos. They won't usually need new pressure plate springs to fix them, just a proper claw adjustment.

Try doing it and tell us all what happens. Good Luck.

dogtor frankarnstein
[Wink]

[Wink]

[Razz]

--------------------
At Projector Heaven the Focus is always on Detail.

____
[o:/o]<|=- dogtor@projectorheaven.com.au
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Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 19, 2013 12:32 AM

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Thanks for the help, i have a film-friend visiting soon who has done this job before,i will let him do it as i don't want to do it wrong!
I will post how i get on ....
cheers,
Clinton

[ March 20, 2013, 12:36 AM: Message edited by: Clinton Hunt ]

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Cheers from me in New Zealand :-)

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Janice Glesser
Film Goddess

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From: Sunnyvale, CA USA
Registered: Sep 2011

posted March 19, 2013 05:54 PM

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I'm having a similar problem with one of my Sanyko 1000's. I'll open a new thread if needed. Frank or Jon can you guide me on how to adjust the claw on my Sanyko as well?

--------------------
Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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David Kilderry
Jedi Master Film Handler

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From: Melbourne, Victoria, Australia
Registered: Feb 2006

posted March 19, 2013 11:36 PM

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Clinton, if the problem happens with all films then it is probably the claw penetration, but I thought you said it only happened to some? I increased the gate tension on my Eumig and it fixed the problem.

All professional projectors have adjustable gate tension for this reason as some film is greener and some is dryer than a regular correctly cured and lubricated print. On professional projectors you back off the gate tension until the image just starts to jump then tighten it up a fraction. Good luck with your projector regardless.

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frank arnstein
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From: Gold Coast. Australia
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posted March 20, 2013 07:35 AM

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Hi Janice,

Jon has basically outlined the procedure for us above.
It involves loosening the 2 hub grub screws with an allen key tool and carefully sliding forward the hub till the claw protrudes about 1mm past the aperture plate when it is in the maximum out position. That should be enough to ensure good penetration into the film.
When you think you have got it right, slowly hand rotate the shuttershaft to observe the claw retreating and ensure it completely retreats from the film before it moves up for another frame grab. It must be seen to go below the aperture plate, where its safe to move up for another grab at the next waiting film frame.

Test with a piece of old film when confident, by hand turning it over. Observe the location of the claw tip within the film sprocket hole, especially with Super 8 film which has a very small sprocket hole. It must be exactly central in the hole or it may cause an unsteady picture if it touches the sides. There is an adjustment for sideways claw-tip relocation if needed. Often it means moving the side film guides a tiny bit.

On the Sankyo 1000, I usually remove the lens holder and lens to provide better visibility of the action going on at the claw tip.

Before you make any adjustment changes, always look at the claw finger to see if a fluff ball has formed on the tip. This buildup of hairs and fluff happens to all projectors and will eventually prevent the claw finger from penetrating the film properly. Then the film jumping begins. So inspect and clean the claw tip and gate rails before making any changes to the claw settings.

Good luck with the adjustment if its required. Take it nice and slow. Use good lighting and magnifying goggles. Be prepared for a number of attempts to get it optimal. Let us know how you go.

dogtor frankarnstein [Razz]

[Razz]

[Smile]

--------------------
At Projector Heaven the Focus is always on Detail.

____
[o:/o]<|=- dogtor@projectorheaven.com.au
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Janice Glesser
Film Goddess

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From: Sunnyvale, CA USA
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posted March 20, 2013 11:13 AM

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Thanks Frank...I'll give it go [Smile]

[Smile]

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Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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Clinton Hunt
Jedi Master Film Handler

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From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 22, 2013 01:05 AM

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....well I got my Filmguard today and cleaned a few films,they play much better,and by looking at the cloth I used it showed the film edges were quite dirty.I think I have solved my unsteady picture problem.
Thanks all [Big Grin]

[Big Grin]

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Cheers from me in New Zealand :-)

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Janice Glesser
Film Goddess

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From: Sunnyvale, CA USA
Registered: Sep 2011

posted March 22, 2013 01:37 AM

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Glad to hear that Clinton. I think my problem is more mechanical. I'll just have to wait until I have some time work on it. I hope I didn't hijack your thread to much [Smile]

[Smile]

--------------------
Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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Clinton Hunt
Jedi Master Film Handler

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From: Waharoa,North Island,New Zealand
Registered: May 2010

posted March 22, 2013 02:07 AM

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Hi Janice,hi-jack as much as you like..that's the beauty of these forums and this hobby.Here in New Zealand my "goto" man for film help and advice lives thousands of kilometers away...ah the internet is tops [Smile]

[Smile]

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Cheers from me in New Zealand :-)

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Barry Webb
Film Handler

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From: Cornwall, England.UK
Registered: Jan 2010

posted March 28, 2013 04:03 PM

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A slight adjustment to the claw worked for me I had to move it back a bit and happy days.
I never had to adjust the film gate I think there was to much claw in the gate due to wear from a plastic cam drive from the Sutter.

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Janice Glesser
Film Goddess

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From: Sunnyvale, CA USA
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posted March 28, 2013 07:43 PM

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Frank...Adjusting the claw seems to be much more difficult on the Sankyo 1000 then these other models...or maybe the lightbulb just hasn't gone off in my head yet [Confused]

[Confused]

First ... The claw is well masked by the pressure plate. Removing the lens doesn't really help and I can't reach one of the screws to remove the lens holder.

Second...Are these the grub screws you mean and if they are...where do I push or pull to adjust the claw?

--------------------
Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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frank arnstein
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From: Gold Coast. Australia
Registered: Jan 2005

posted March 30, 2013 10:20 AM

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Hi Janice,

Those are great pics.

To remove the lens holder, a long shafted Philips head screwdriver will do the job. It will just squeeze past the focus knob and get onto that tricky rear screw. If you can't get it off then peer through the gap at the film gate or look down into the lens barrel to watch the claw tip as it extends into the film path. Turning it over by hand, use a magnifying glass to see the depth of claw penetration occurring.

As for the 2 grub screws, you have correctly located them on the shutter hub. When loosened, the shutter will slide forwards or back on the shaft, taking the cam with it and so altering the depth of claw tip. When loosened push the hub and it will slide.

When you have set it up OK, hand rotate it to see if the claw retreats properly. Then check that the claw tip is in the middle of the film sprocket hole. Use a piece of test film to crank through the gate. Adjust the side film guide to centralise the claw tip in the sprocket hole if required.

good luck with it Janice
report how you go.

dogtor frankarnstein
[Wink]

[Wink]

[Smile]

--------------------
At Projector Heaven the Focus is always on Detail.

____
[o:/o]<|=- dogtor@projectorheaven.com.au
//``\\
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Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010

posted April 08, 2013 10:37 PM

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Hi all, here's an update on my Chinon 7500MV bouncy picture......the filmguard did help on a very small number of films I have cleaned and screened, so I now think that isn't the problem with the projector and maybe it is the other things that members have posted here [Frown]

[Frown]

.
I have sent it to my friend who repairs these things for him to have a look at [Smile]

[Smile]

and will let you all know what the outcome is.
Hopefully it will be fixable as it is in new condition with very little use over the years.
Cheers from me in New Zealand

--------------------
Cheers from me in New Zealand :-)

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Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010

posted April 23, 2013 06:26 PM

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....it was a loose filmgate....tightened it and it runs like a dream..... [Smile]

[Smile]

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Cheers from me in New Zealand :-)

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Brian Stearns
Master Film Handler

Posts: 487
From: Lexington
Registered: Jun 2013

posted July 27, 2013 03:14 AM

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Very helpful topic,this forum is a great database for answers.

My projector had this problem only when adjusting the framer, made the image shake. I went in and cleaned everything out and noticed globs of dirt around the claw.This was probably my problem I have been having. the framer nob was hard to turn and shakey image when adjusting.I'll have to see if everything is ok if not I'll have to do the claw adjustment

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Brian Stearns
Master Film Handler

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From: Lexington
Registered: Jun 2013

posted July 27, 2013 03:15 AM

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Very helpful topic,this forum is a great database for answers.

My projector had this problem only when adjusting the framer, made the image shake. I went in and cleaned everything out and noticed globs of dirt around the claw.This was probably my problem I have been having. the framer nob was hard to turn and shakey image when adjusting.I'll have to see if everything is ok if not I'll have to do the claw adjustment

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Maurice Leakey
Film God

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From: Bristol. United Kingdom
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posted July 27, 2013 04:39 AM

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The claws on a Super 8 projector are very small, and whilst most owners clean the gate they seldom pay any attention to the claw.

The claw can pick up small bits of muck, sometimes badly made tape joins, and over time will these will build up to give problems with projection.

Use a very small artist's brush and very gently clean occasionally.

--------------------
Maurice

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Brian Stearns
Master Film Handler

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From: Lexington
Registered: Jun 2013

posted July 27, 2013 06:18 AM

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Everything is tight and hard to see, so I had to use a flashlight to notice the dirt. I would think compressed air would work as well

Like I said it only shook when I used the framer.

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Brian Stearns
Master Film Handler

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From: Lexington
Registered: Jun 2013

posted August 01, 2013 07:40 PM

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Chinon8000 variant model,I can play film ok for about a minute or so then the film starts to shake. Do you know if it's a bent claw or not good pressure gate or claw penetration?

Don't know how to access the film gate to measure penetration or see if anything is bent. I cleaned the claw so that's not the problem

Any tips

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