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Steadiness Test Chart and procedure


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Hello, 

I'm conducting a super 16mm steadiness test on an Aton LTR and was wondering if anyone knows where I could download a steadiness test chart?
So far I found one from a French webpage but it doesn't look like the one I know.

I also take the opportunity to double check the procedure since it's been a while since I did one:

1 - 25 mm lens
2 - Make sure the chart occupies the entire frame
3 -  Center the camera with the chart (use a mirror to help)
4 - Load virgin film
5 - Mark the first frame in the gate of the camera with a big "X
6 - Try to use a higher F stop
7 - Under expose 1 stop
8 - Let it run for 20 seconds
9 - Rewind the film (use a darkroom or changing bag), rethread the camera and load it so that the "X" appears in the gate to fill the frame as it did in the first pass
10 - Reframe slightly to the right/left and up/down so that the chart lines are in a different position but still parallel to each other
11 - Under expose 1 stop (again)
12 - Run the same film for a second time

 
I'm in doubt about step number 10. The image attached is an illustration of what I meant!
 
Thanks in advance.
 
Best,
Marta S.

1st passage.jpg

2nd passage.jpg

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All you need to shoot is any grid of lines twice, the second exposure pass with the camera slightly shifted. You're looking to see if the two grids stay locked versus moving relative to each other.

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Like David has pointed out, you only need a grid really. However! I do have a chart that was kindly sent to me by forum member and Senior Technician/Designer) at Visual Products @Paul Scaglione

I'm sure Paul does not mind me sharing, PM me your email and I'll send it over :). 

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I used to twist the chart slightly for the second pass, which shows you very clearly if there is any movement between the two grids when you view the test because the second grid is angled to the first. But you can also offset the grid as you pictured.

With cameras like these or SRs where the mag has a pressure plate and plays a role in the steadiness you should do a seperate test for each mag. If you want to shoot high speed you should test different speeds too. Label the chart on one pass so you know which mag is being tested.

Make sure the camera is firmly supported so external vibrations don’t give you a false result.

With 35mm, marking the first frame is important because there are 4 perfs per frame so you could accidentally offset the frames for the second pass, but with 16mm it’s not necessary as there is only one perf per frame, and you’re just rewinding to the start of the roll. 

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