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Weird "bar" effect in B&W 16mm testroll - HELP


Willem Jansen

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I've just received the first footage I'd shot with my Eclair. To my surprise, there's a weird bar (clearly visible in the upper middle) throughout the whole footage. It looks like some sort of reflection. I've posted a screenshot underneath the text.

 

I shot in natural light and the sun was behind us. I used a lightmeter and as far as I know, I did everything right. I often went two stops further but in the shots where I used the lightmeter, the bar is there also. The camera had been serviced by Bernie a while before, so I can't imagine anything wrong inside the camera.

 

Could anyone help me further?

 

https://postimg.cc/image/ewxy5ypnb/

Edited by Willem Jansen
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That top thing? Looks like a mattebox shadow from the light source.

 

 

Well, the sun was behind us and I used a lightmeter for correct exposure. So I can't imagine that it's the mattebox.

Also, it's visible throughout the whole footage. Including shots where I did some handheld where the lighting was a lot less brighter than in the screenshot I posted here.

 

But for the most part I'm guessing since I have no clue what the hell it is.

If anyone knows please let me know.

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Someone who knows the Eclair will have a good idea, but it's a light leak or flare from the bottom of the camera. The dark bar is the projection of some straight edge very near the gate, hence the sharp shadow. Some looking through the gate with the shutter open and a light in front of the camera, lens off, may reveal it.

I'm sure you'll get some more detailed answers here. I got something somewhat like this when I had a bad light seal in a Hasselblad film magazine. Hence the light coming in from an oblique angle and casting a "shadow", in that case, of the film gate.

Edited by Mark Dunn
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Yeah, I just shined some bright light into the camera and looked through the viewfinder. There's a small light leak at the bottom, but have no idea and thus far figured out where it exactly breaks in (the viewfinder or somewhere else?)

Edited by Willem Jansen
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This may be it. Or at least one of them:

Anyone who thinks the same? When I looked through the viewfinder and layed my finger on it, the leak seemed to disappear. But this could also me my finger blocking the light... :rolleyes:

 

 

post-73387-0-28922500-1533288099_thumb.jpg

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Does your camera have a gel filter slot open on top of the camera? I know the old ACL did and could fog film if it was left out.

 

Not sure if it was retained on the ACL 2...

 

Verne and Sylvia Carlson in "The Professional Cameraman's Handbook" (pg 317, 1st edition on the ACL), "CAUTION; Filter holder must be inserted into camera to avoid fogging film - whether or not gelatine filter is used."

 

Also: "Always insert holder with chamfered side forward..."

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Had a talk with Bernie yesterday. I've since then closed the gelatine holder with tape and the C Mount plate on the front of camera, but it didn't help any unfortunately. I also have to remove the C Mount plate to see if there are any gaps between the rim and edge of the plate. Or that it was screwed in tight enough. But since I already taped it off before and nothing changed, I'm waiting with that.

 

I'm kind of running out of options. I've been looking through the viewfinder most of the times to see what's going on. There's this tiny light shining at the bottom. When I turn the inching knob, I can see the claw moving in that little light from left to right(!) I'm starting to wonder if that's maybe it. But at the same time, maybe it's supposed to be there and am I looking completely at the wrong thing. Right now, my guess is, is that it's a reflection coming from something that I haven't figured out yet. The ground glass, maybe?

 

Bernie and I have another telephone call planned later today as we both want me to figure it out myself and try to fix it. He's of great help so far and I hope we get there. But the opinions or ideas from folks here is also still greatly appreciated.

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I did. And as weird as it may sound, I'd like it to be the case. However, I've now shined a led light a couple of times on the c mount and around other places on the camera in a dark room to see if there are any gaps, letting through light. But the camera seems to be tighten up the way it should be. Which is great. But also states that something else is causing the problem.

 

For the Eclar ACL owners on this forum: When I look through the viewfinder and see the ground glass, I see a vague bit of light on the bottem, in between the eyepiece and ground glass. When I turn the inching knob, I see the shadow of the pin claw moving from left to right. That bit of light is there even when not turning the inching knob. Is this normal? Or...

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Hey Willem,

Which ground glass do you have, which eyepiece do you have? I had a look, an ACL II, big self leveling Kinoptik finder and Visual Products S16 ground glass. Took the lens off and shone a light into the port. Didn't see any of your observations. But the viewing image is big with only a small periphery. The Angeneuix finders I seem to remember have a wider periphery, the visble area outside of frame, they may allow what you saw.

 

What exactly did Bernie say? Is he making you think, solve it yourself, like a test or a right of passage....

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I have the normal 16mm ground glass with the small rotatable viewfinder.

Bernie told me to tape off the gelatine filter holder and c mount plate, which I did but didn't seem to do anything really.

The next step was to take off the c mount and see if it leaked light. But I don't have the right screwdriver to take off the screws, so I haven't done that yet. Also, in the meanwhile, I've shined a light on the c mount in a dark room to see if light came through which didn't. Kinda wondering if taking off the c mount is actually worth doing then.

 

Bernie helps me doing it myself so I can learn more about the camera and so I don't have to ship the camera all the way to NY for him to take care of it. It hasn't been that long since it was actually over there for a CLA. But seen how things are going right now, I might just be better off by sending it over to him and have a professional looking at it.

 

Here's a photo of the viewfinder on my ACL II:

post-73387-0-07894400-1533547964_thumb.jpg

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Are you sure your ACL is ACL 2? Just wondering since that small viewfinder is AFAIK the one the ACL 1 shipped with. I have ACL 1.5 and it has the Angenieux finder, I have also owned an ACL 2 which had the big Kinoptic finder.

 

Is there any flicker in the image or is that bar there just all the time? In darker scenes, is there that reflection as well (the one in the upper center part of the frame)?

 

If there is no flicker, the cause of that bar is not in the mount area. Swinging mirror would cause flicker to light leaks from that direction.

 

Some people with ACL 1 have reported having had problems with the clapper light being broken and exposing the frame from below (due to the bulb glowing a bit). I guess that wouldn't really show up in the finder though, except perhaps in very dark conditions when the camera is running.

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I actually also assumed mine was an ACL 1. Because it has the Jaeger input and not an XLR. But Bernie told me it's a ACL II when he serviced it and it says so on the receipt with the serial number next to it.

 

In the footage that I shot is actually some flickering. Not much per se, but it is there at some moments. Most clearly seen from the left of the screen.

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Update: Talked to Bernie again and we think it's the lens that I used. Everything in and around the camera seems perfectly fine and found nothing. The lens that I used, a Pentax Takumar, isn't a good combination with the Eclair. Too much light comes through and overexposed the film. Bernie sends over a 16mm lens so I can make another test. I don't have a lot of experience nor knowledge about lenses, if anyone wonders how I could make that mistake ;)

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This makes sense, the Takumar is a 35mm stills lens with a large exit pupil. A lot of light will hit outside of the filmgate, scattering light and bouncing off reflective surfaces.

 

 

Yeah I bought that lens when I had a Krasnogorsk 3. Thought it would also work with the Eclair... Oeps

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