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k3 camera with different problems.


marius kildalsen

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Hi.

I do have multiple problems with my k3 camera.

First it looks like the backfocus on the standard 17-69 zoom lens is a bit off. Its hard to see this in the viewfinder but I can clearly see it in the scanned film. Does anyone know how to adjust the backfocus on these lenses? I dont think any of the local camerahouses can do it on this mount. You could see it in the first 30 seconds of this clip.

Its a bit hard to see this in the viewfinder thats why I did not see it during takes.

 

 

And I also had some problems with the test roll. I did use mutiple frame rates, 8-24-32-48 when shooting this and scanned it at 24. From aprox 00:30 the probem with the film appears. Does anyone know what this could be? Or could this just be the film not alligned correctly because I jurked around with the frame rate?

 

 

https://vimeo.com/306043963

Thanks

Edited by marius kildalsen
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Well, the jitter issues are pretty much the loop size. It lost one of the loops and was pulling the film down wrong.

 

I've had zero luck making my K3 work properly without modifying the spring assembly on the pressure plate. For some reason the film doesn't stay in position between pull downs on my camera. So I had to make the pressure plate push harder on the film and the problem went away. Id acquire a roll of test camera negative and run a bunch of it through the camera with the side off so you can see if it's working properly. My guess is, it skips/jumps every start stop just enough to where the loop goes away.

 

Flange distance on these is hard because the mount screws into the front of the camera which doesn't fit as snug as other cameras. Remember, it's a very cheap camera so it's probably just a tiny bit out.

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How did you adjust the pressure plate? The screw that keeps the spring in place?

The backfocus I can work around using other lenses, but it would be great to have a zoom in working conditions.

Yep, turn that screw and slide the little sliver thing towards the pressure plate ever so slightly and it will put more pressure on the spring. I tried different springs, but they didn't seem to help as much.

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I agree with Tyler, it's one or both loops.
In order to lose the loops, it is sufficient even if ONE perforation is damaged.
Although the image seemed to recover for a few moments, but perhaps only because the speed was less.

I also noticed some light leaks that seemed to predict instability. Usually the light infiltrations, common in K3, are random in the image, while I saw that in your case there is one that often appears in the upper half of the frame.

As for the focus: the regulator of the diopter was set according to your eye?

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Luigi. Yes the viewfinder was set to my eye. I Did test it today with a similar lens. I Also did put my lens on the other camera and I could not find anything wrong with it.

However I did tighten the pressure plate towards the gate and the film locks in a bit more.

Could it be that there is nothing wrong with the lens, only that the film was a little bit loose? Could this shake it out of focus?

 

Thanks

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I can tell right away that your camera was modified to S16, and nothing weird going in when you zoom in and out means the lens was re-centered as well. I'm going to assume you converted the camera yourself or that a technician did it but he or she didn't collimated the lens, or maybe you just bought the camera already converted. I converted my camera myself and I bought the re-centering ring and I can tell you it was poorly machined and it was bigger than the original one, that is something that changes the focal flange distance of the lens and it causes it to lose collimation.

 

I know what you mean by back focus, but in cinema lenses and specifically on the K3 lens there is not a back focus ring like the one on lenses used with ENG cameras. If you want to use the zoom in, focus, zoom out, shoot technique you will have to get the camera /lens collimated by a technician who is going to measure the distance from the lens mount to the film gate and make physically make changes to the mount or shim it to get proper distance.

 

If you don't want to spend the money or if you can survive without zooming while filming and the zoom in, focus, zoom out, shoot technique your film should be in focus if you just focus by eye. It can be complicated with wide angle lenses, but that's the K3.

 

A good idea to make sure you are getting the best results out of the viewfinder is to adjust the diopter to your eye by setting the lens to a blurry or out of focus position, point the lens towards a light source and fine tune the diopter to the point where you can see the grain on the ground glass as sharp as possible.

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No problem, well since you have the original ring you can put it next to the one mounted on the camera and you will see they are not exactly the same. I'm not looking at your camera, but I know those adapters were poorly machined.

 

Is not a good idea to change the mount now, the gate was widened and the center of the new frame (S16) is not the same as the previous one (R16) if you change the lens you would get a weird effect when you zoom in and out, maybe not on the viewfinder if it was not widened but on the film for sure. The other factor is even if you use still photography lenses designed to cover a much bigger area you would be using the side of the lens. Most lenses have the best optics in the center, and the last factor is going back to the original mount would not fix the problem because it was touched. If you want to have perfect collimation you don't mess with mounts, as soon as the original mount was removed the colimation was lost. Now collimating a mount is not impossible, is just a matter of having the right distance (45.46 mm) between the mount and the film plane, but when you don't have the tools and the experience it can be complicated. When I converted my camera I got it close to proper focal flange distance using sand paper to reduce the size of the adapter, but it can be challenging.

I would suggest getting some M42 lenses, they are inexpensive and have good quality with the benefit that they cover the S16 area without a problem so you would not get vignette. Personally I don't like using zoom when I'm filming so that was not exactly a problem for me.

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No problem, well since you have the original ring you can put it next to the one mounted on the camera and you will see they are not exactly the same. I'm not looking at your camera, but I know those adapters were poorly machined.

 

Is not a good idea to change the mount now, the gate was widened and the center of the new frame (S16) is not the same as the previous one (R16) if you change the lens you would get a weird effect when you zoom in and out, maybe not on the viewfinder if it was not widened but on the film for sure. The other factor is even if you use still photography lenses designed to cover a much bigger area you would be using the side of the lens. Most lenses have the best optics in the center, and the last factor is going back to the original mount would not fix the problem because it was touched. If you want to have perfect collimation you don't mess with mounts, as soon as the original mount was removed the colimation was lost. Now collimating a mount is not impossible, is just a matter of having the right distance (45.46 mm) between the mount and the film plane, but when you don't have the tools and the experience it can be complicated. When I converted my camera I got it close to proper focal flange distance using sand paper to reduce the size of the adapter, but it can be challenging.

 

I would suggest getting some M42 lenses, they are inexpensive and have good quality with the benefit that they cover the S16 area without a problem so you would not get vignette. Personally I don't like using zoom when I'm filming so that was not exactly a problem for me.

Thanks. Ok then I wont do that. Yes I already own some m42 lenses that i have used for stills. Maybe I should just comit to those witout worrying. I am not a big fan of zoom in the middle of a shot myself, but I would prefer not bringing so many lenses around. Especialy since this is more a hobby camera for personel projects. I do have a 50,85 and looking for 35. Any suggestions for an even wider lens?

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The meteor lens is very good really, but when you have a converted camera you cannot take advantage of it because it will vignette on the wide side as you can see on your film. I think M42 lenses are the way to go, considering that the crop factor of S16 is 3X I don't think you need to have more than two lenses most of the time. You already have a 50mm x 3 =150mm and a 85mm = 255mm I would suggest searching on eBay for a 28mm f2.8 those were very common and you can find an inexpensive one. For the wide angle end there are two good options, the Peleng 8mm which is equivalent to a decent 24mm on FF and the Zenitar 16mm, you can buy those brand new and they won't break the bank. I have a film on YouTube titled "Santa Monica on Super 16" I whot that one with a converted K3, and Zenitar 16mm, Vivitar 28mm f2.8, Super Takumar 50mm f1.4, a 85 and a 135mm.

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I was of the idea shared with Tyler on the distance of the film in the gate, I had not thought about the lack of collimation; interesting.


At this point I add: it's not convenient to convert the K3 in Super 16mm. Or have to make a professional laboratory, that really knows what it does. It is also at risk to buy it already modified on ebay.


However, I also agree with Marius's vision: with the K3 it is a bit 'annoying to bring with you various lens, it's a camera more for "shot and go". But at the same time it is not convenient to repair it...

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Luigi,

 

The film shows two different problems, jitter and out out focus. I didn't comment on the jitter problem because one I agree with Tyler and second I know that a converted K3 will be unstable.

 

The moment you decide to unscrew a part of a camera you are messing with parts that must be perfectly aligned and you will have to pay a cost for doing that, still I would really like to find a virgin K3 with the only intention of modifying it it to S16 and document the process. I think the K3 is what it is... a beautiful camera that can teach you a lot, a camera that you can use to learn, and a camera that you can love, but that doesn't change the fact that it is an affordable camera with no crystal sync motor, with no orientable viewfinder and video tap, it's just a K3

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