Author Topic: Video Teardown & Repair of a Stanford Research PS350 5000V DC Supply  (Read 13146 times)

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Offline HugoneusTopic starter

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Re: Video Teardown & Repair of a Stanford Research PS350 5000V DC Supply
« Reply #25 on: July 13, 2015, 02:31:15 pm »
The camera is set to indoor lighting, but the exposure is on auto.

Offline Lightages

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Re: Video Teardown & Repair of a Stanford Research PS350 5000V DC Supply
« Reply #26 on: July 13, 2015, 04:25:38 pm »
Florescent lights are the nemesis of video. "Indoor lighting" assumes incandescent lighting of a color temperature around 3900°K and black body radiation spectrum. Florescent light are usually around 4400-4700°K and have peaks at some colors. This makes the image look yellow/green instead of normal. It should be possible for you to set the color temperature to florescent, or use a piece of white paper and do a manual white balance. This still won't be correct because white paper is actually a bit bluish but it will be much better than the mismatch with the color temperature settings you are using now.

The auto-exposure issue is a bit fiddly to correct but not expensive. Set your seen up, make sure there are no specular reflections from the lighting and then lock the exposure. If you find the image to bright or dark, then if your camera has manual compensation control, but that up or down to get it closer to correct. If not, Stick your face on the scene and lock exposure on that. Again, it won't be perfect but better.

The better way is to buy one of these. It won't break the bank  ;D
http://www.bhphotovideo.com/c/product/101853-REG/Delta_22030_Gray_Card_8x10_1.html
and one of these
http://www.bhphotovideo.com/c/product/300868-REG/Porta_Brace_WBC_White_Balance_Card.html
 

Offline Muxr

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Re: Video Teardown & Repair of a Stanford Research PS350 5000V DC Supply
« Reply #27 on: July 13, 2015, 07:18:36 pm »
So the first thing that caught my eye with this unit was how it wasn't sitting flush on the table. You'll notice the front left leg is lifted off the table. My guess is that it was dropped, and it's the most likely reason why the 15V regulator had its pins severed due to the transformer weight on that side.
« Last Edit: July 13, 2015, 07:20:22 pm by Muxr »
 

Online MarkL

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Re: Video Teardown & Repair of a Stanford Research PS350 5000V DC Supply
« Reply #28 on: July 23, 2015, 02:07:28 am »
I was surprised you trusted the survival of your nice Fluke to a single 1G resistor at the input of the voltage divider.

Perhaps that 1G resistor is rated for 5kV, but it doesn't look like it to me.  I'd be worried about arc-over or internal breakdown.
 


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