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Sony A7S - Stripped down a 4th time

Started by MarkS, Sep 03, 2015, 20:10:11

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MarkS

Last night I stripped the A7S down for the 4th and (hopefully) final time.  I can now get the sensor out in 15 minutes!

So why the 4th time?  Here is the brief history:

1) Stripped out the internal filters.  This worked well on the scope but my old lenses would no longer bring stars to focus.

2) Installed a 3mm non-reflective Edmund Optics glass replacement.  Unfortunately this made an internal IR light leakage more apparent - the IR LED was leaking from somewhere inside the shutter mechanism.

3) Installed some internal shielding.  Old lenses would focus stars but nowhere near the infinity setting.  Calculations showed that the sensor needed to be 0.35mm further back.

4) Installed some 13 thou spacers (=0.33mm) cut from a old feeler guage. I was worried that 14 thou (.355mm) might be just too much.

The result?  The old lenses focus on stars very close to their infinity mark.

So hopefully this is the end of it.  I just need to make the relevant spacing adjustment on the Tak Epsilon DSLR adapter and I'm ready for a Winter of stonking imaging!! 

El Nino permitting :(

Mark

RobertM

Great work Mark, hopefully that's for the very last time.  Still can't believe you've taken it apart so many times but 15 mins is quick !

when you say the sensor needed to be further back do you mean closer to the lens i.e. you added the 13 thou spacers ?

Robert

MarkS

Quote from: RobertM on Sep 03, 2015, 21:29:25
Great work Mark, hopefully that's for the very last time.  Still can't believe you've taken it apart so many times but 15 mins is quick !

when you say the sensor needed to be further back do you mean closer to the lens i.e. you added the 13 thou spacers ?

Robert

I added spacers, which moves the sensor backwards away from the lens.

Mark

Kenny

Might have been easier to build your own camera.  ;) :lol: