8mm Forum: Unstable image with 16mm camera

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Posted by Robert Neia (Member # 890) on January 03, 2017, 12:10 AM:

Hi everyone,

I picked up a bell and howell H16 and am having some problems with it. After shooting a test roll, I noticed that the image is not stable when projected. It's a little hard to describe, but basically the image violently shakes up and down. I thought it might be the projector, but I tested it with other film and it didn't have any issues.

I'm wondering what could be the problem. Could it be a problem with the pressure plate? If it's not a problem with the pressure plate, what else could it be?

I'd appreciate any help!

Posted by Terry Sills (Member # 3309) on January 03, 2017, 02:53 AM:

Robert
Don't you mean a BolexPaillard H16?

Posted by Robert Neia (Member # 890) on January 04, 2017, 12:49 AM:

Hi Terry,

That's exactly what I meant to say! Sorry for the mistake, it was late at night when I was posting this! Just to be clear, I have a BolexPaillard H16. Any suggestions on what might be wrong?

Posted by Robert Lewis (Member # 1458) on January 04, 2017, 03:52 AM:

From what you say it might be that somehow you lost one or both of the loops which are normally formed by the guides above and below the pressure plate. In my experience this doesn't happen, but it would be worthwhile checking both loops immediately after loading film and immediately after the guides have withdrawn. Another possibility is that you didn't have the pressure plate fully locked in position and it released itself. It might therefore be worth loading some waste film in daylight and observing how the film loads and that it moves through the gate smoothly whilst maintaining the loops.

Posted by Paul Mason (Member # 4015) on January 05, 2017, 01:19 PM:

I think Robert Lewis is likely to be correct. A Bolex or Bell & Howell 16mm camera should be run for at least 3-5 seconds after loading to check the film is running through the gate and both loops are stable before closing the back.

Posted by Barry Fritz (Member # 1865) on January 05, 2017, 02:02 PM:

Paul. I think you meant to say projector, not camera. Robert, what projector are you using?

Posted by Robert Neia (Member # 890) on January 05, 2017, 11:35 PM:

Hi Barry,

I'm using a Singer Insta-load projector. I've already played some other film on it to test if the projector is working properly. The only time I had image stabilization issues was when I played the filmed shot with the Bolex H16.

I'm going to run some film through the bolex and see how smoothly everything works. I will upload a video of the film running through the camera shortly so you all can take a look. Thank you very much for your help.

Posted by Barry Fritz (Member # 1865) on January 06, 2017, 06:19 PM:

Certainly doesn't sound like a loop or pressure plate issue with the projector then.

Posted by David Michael Leugers (Member # 166) on January 09, 2017, 05:30 PM:

Is the image very blurry or is the image normal but jumping up and down during projection? On the Bolex if you have the shutter in "T" when filming normal you will get the blurred images, check to see that the little selector arm is pointing towards "I". Later model reflex cameras have a knob instead of a lever.

Posted by Robert Neia (Member # 890) on January 09, 2017, 10:57 PM:

Hi David,

Thanks for the reply. I just took a look at my camera and the lever is pointed to the "T". Do you think that could also be the issue to the unstable image? Or just the blurriness?

Posted by Paul Adsett (Member # 25) on January 09, 2017, 11:03 PM:

Run the film taken on the Bolex H16 through the projector again, but this time adjust the framing knob on the projector so that the frame line between the pictures is clearly visible on the screen. If the frame line is jumping up and down then it is an issue with the projector. If the frame line is steady, but the picture is jumping up and down in relation to the steady frame line, then it is a camera issue.

Posted by Robert Neia (Member # 890) on January 09, 2017, 11:07 PM:

Hi Paul, I actually did that a few days ago. The frame line is steady, but the picture is jumping around.

I've uploaded a video of some junk film running through the camera. Can you guys please take a look at it and let me know if everything looks alright?

Here is the link:

test film going through camera

Posted by Terry Sills (Member # 3309) on January 10, 2017, 03:12 AM:

There's no obvious chattering of the gate, but the bottom loop looks too small which might be the problem. I don't think the film should be touching that post, which it appears to be doing in that video clip.

Posted by Maurice Leakey (Member # 916) on January 10, 2017, 03:43 AM:

See my attached video showing how to load. It appears that the loop formers have not been released after loading.
https://www.youtube.com/watch?v=ZV0JE_gz7hM

Posted by Robert Lewis (Member # 1458) on January 10, 2017, 04:24 AM:

Robert ... In my earlier response to your original posting, I suggested that the loop formers had not been released and withdrawn or that somehow you might have lost any loop formed. Having now seen your video, it is quite clear that the camera is running with the loop formers still in place. Also, the video shows that there is no bottom loop at all and the consequence of this is that the film is running tight around the bottom post of the pressure plate. The top loop is also very small. I would not have thought that the top loop being small would necessarily be a problem, but the lack of a bottom loop and the consequential running of the film around the bottom post of the pressure plate would almost certainly cause a very jerky image. I think there is also some chatter from the pressure plate. You can't actually see this in the video, but I think the possibility is supported by the fact that there is something about the noise created by the film running through the camera. It is not normal in my experience. If there is chatter from the pressure plate, this would also cause a lack of focus because if the pressure plate is chattering that means it is moving as the film is tugged around the bottom pressure plate post referred to above.

Posted by Robert Neia (Member # 890) on January 11, 2017, 12:18 AM:

Hi Robert and Maurice,

Thank you very much for your inputs. Maurice, I took a look at the video you sent me. It appears I was loading the film incorrectly and this video helped a lot.

Robert, thank you very much for your input. Like you said, the bottom loop is non-existent and the film is running against the pressure plate post. I tried loading the film according to the directions in the video posted by Maurice... what happens is that the top and bottom loops form, but only for a few seconds. After a few seconds, the loops get very tight just as in the video I had originally posted. I'm convinced I'm following the loading directions correctly.

Here are the steps I am taking to load the film:
1. Let the camera run allowing it to take up the film.
2. Once the film moves through the top and bottom loop formers, I stop the camera and thread the film onto an empty reel.
3. I then release the loop formers and start the camera again. Its as if the force generated when starting the camera excessively pulls the film, making the loops before and after the pressure plate tighter.

Does any of what I'm trying to describe make sense? Sorry, I know there is a lot of detail to here, I can try and take another video if that would help.

Posted by Tom Dee (Member # 4468) on January 11, 2017, 02:05 AM:

Have you tried running the camera at different speeds to see if the loops change running slower vs faster.

Posted by Maurice Leakey (Member # 916) on January 11, 2017, 03:56 AM:

Robert
As you say, it certainly looks as if the take-up spool tension is too tight when it starts, allowing it to over-ride the auto loop settings.
Perhaps someone may be able to advise if any adjustments can be made.
Oldtimer Cameras, here in the UK, can supply paper copies of H16 service manuals.
http://www.oldtimercameras.com/search/fullsearch.asp?SearchQuery=H16

Posted by Robert Lewis (Member # 1458) on January 11, 2017, 04:03 AM:

Robert... I have to say that I am puzzled. The upper and lower sprockets are related and therefore the upper sprocket pushes film forward to the gate and the lower sprocket pulls film from the gate and so unless something goes wrong if the bottom loop is lost, I would expect the upper loop to become larger. Assuming that the pressure plate is properly in place and secured (and looking at your video it appears to be) the claw should be moving the film through the gate at a speed which is consistent with the turning of the upper and lower sprockets, so maintaining the upper and lower loops.

I think Tom's suggestion that you try to establish what is happening if you run at the slowest speed you can (this is probably 12 frames per second) is excellent

From your video, it almost as if the claw is not doing it's job part of which is to hold the film in the gate frame by frame, and instead, the lower sprocket is pulling the film through continuously thereby causing the lower loop to disappear, leaving an upper loop, albeit small, in place. So make sure that the pressure plate is properly installed and try to establish if the claw is working correctly. You could also try marking and measuring the length of film from sprocket to sprocket when you first load the film, and then compare the length of the film sprocket to sprocket after the lower loop has been lost.

One last question ... Looking at the video as closely as I am able, I almost have an impression that the film is loaded with the sprocket holes nearest the film chamber door, but that could be a mistake on my part or you are using a length of film which has double sprocket holes. The sprocket holes on single sprocket film should be furtherest from the film chamber door, and I am wondering whether, if it is single sprocket film, you have it loaded the correct way. It might just worth checking.

Regards.

Posted by Robert Neia (Member # 890) on January 12, 2017, 01:04 AM:

Hi Robert,

Yes, the test film I was using had double sprocket holes. The upper loop is much larger when running the camera at a lower speeds such as 16 frames per second, the lower loop is still non-existent.

I removed the pressure plate to make sure the claw was there and in good shape. Everything seemed to be alright.

There is one thing I forgot to mention. I'm sure this has nothing to do with the unstable image, but I am using a 12.5mm lens...I thought maybe the lens could cause some kind of image distortion that I could be mistaking as an unstable image? Just a thought.... This was a lens that I recently bought and have not used before.

Other than running another roll of test film, I'm not sure what else to do. I'll continue playing around with it and see if I get anywhere.

Posted by Robert Lewis (Member # 1458) on January 12, 2017, 03:19 AM:

Robert ... I can't see how the lens can have any effect on the loss of loops. Bolex cameras are pretty reliable and well built, and I am very suspicious of the film you have used. Is this the only film you have tried to put through the camera? Looking at your video, I am pretty certain that your camera has single sprockets, so why are you using film with sprocket holes on both edges of the film? Have you ever put single sprocket film through the camera? What film are you using? I ask these questions because it just might be that the film you are using is not the correct specification. One can get film with different pitches, both 2994 and 3000. Bolex cameras usually use 2994 pitch film and are "uncomfortable" if 3000 pitch stock is used. Using film punched with the wrong pitch is known to have caused jamming and loss of loops, and unusual noise is often caused. (You will recollect that earlier on I commented about the strange noise picked up in the video). Have you ever used single sprocket film in the camera?

I think we are now drilling down to what might be significant.

Posted by Robert Neia (Member # 890) on January 15, 2017, 01:13 AM:

HI Robert, sorry for the late reply.

I've used tri-x (single sprocketed) and wittner chrome 200d, which is the double sprocketed film you saw in the video. The image was unstable with both film stocks. How can I tell what the pitch size of the film I'm using? I don't think I've ever seen pitch size labeled on any of the film packages I've used...then again, I may have completely over looked it. Thank you again for your help. Can you point me to a film stock that does use the correct pitch size?

Posted by Robert Lewis (Member # 1458) on January 15, 2017, 04:20 AM:

Hi Robert. Hmmm! Kodak Tri-X is 2994 perf - if you look at the packaging you will see to the left of the Bar Codes "16 1R 7605(2994)EIB). The "2994" indicates that it is perforated at 2994.

As for the Wittner Chrome 200D stock, I am not sure. I have never used this stock, but I did once buy some ORWO 54 stock and I and I think others had problems with it. It seemed to be not liked by some cameras, and when I checked I found it to be perforated at 3000.

Usually you don't need to check the perforation specification of stock, because the standard for cameras is 2994, but some of the stock one can get can be a problem. So it is always wise to ask the question. My understand is that 3000 perf stock is a stock often used for projection prints.

You can check the perforation specification of stock by over laying a short length of the stock in question on a short length of a known 2994 stock. If the stock you are checking is 3000 the perforations will not match. To check line up the first sprocket hole and all of the other holes should line up too. If the two sets of holes drift away from each other, you know you have a mismatch.

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