07:50 | se6astian | sure: https://cloud.apertus.org/index.php/s/WCE3Z5G5wxQLMYA?path=%2FCNC%20mill
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07:50 | se6astian | e mount V4 Drawing.pdf
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09:50 | anuejn | what is the distance from the sensor surface to the bottom surface of this part?
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10:09 | se6astian | https://wiki.apertus.org/index.php?title=AXIOM_Beta/Enclosures#E-mount_FFD_verification
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12:56 | anuejn | so its 9,128mm distance from the sensor plane?
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12:57 | anuejn | with 4 m4 holes in a distance of 56mm
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12:57 | anuejn | is that right?
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13:24 | se6astian | 4.994mm from sensor to outer surface of cp enclosure and then 2mm for blank filter and 2.378mm for UV/IF filter, then 0.15mm shims = 9,522mm
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13:27 | se6astian | 4x M4 clearance hole in 56mm grid, yes
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13:54 | anuejn | thanks :)
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14:04 | anuejn | is it important, that the cover glass has a different refraction-index?
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14:05 | anuejn | or the filters?
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14:18 | anuejn | and why is the UV/IR filter such an odd thickness?
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14:26 | se6astian | <anuejn> is it important, that the cover glass has a different refraction-index? you mean compared to air or compared to glass?
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14:26 | anuejn | compared to air
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14:26 | anuejn | so does it make the path longer because the light travels slower?
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14:26 | se6astian | yes, 0.244mm is a significant distance change it causes
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14:27 | anuejn | ah thats what is meant
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14:27 | anuejn | now I get it
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14:28 | anuejn | is that also why the UV/IF filter is 2.378mm and not 2mm?
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14:28 | se6astian | and the 2.378mm thickness of the UV/IR filter is also exactly for countering the glass density light path distance change
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14:28 | anuejn | I see
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14:28 | anuejn | so it is physically 2mm thick?
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14:29 | anuejn | and what happens if I insert another filter?
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14:29 | anuejn | will that not cause problems then?
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14:30 | se6astian | well this system is designed exactly so you can switch filters but the glass and metal parts are married together
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14:31 | se6astian | any filter needs to have a thickness that compensates the glass in it for 2mm thickness
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14:31 | se6astian | 2mm thickness of air basically
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14:31 | anuejn | ah okay
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14:31 | anuejn | thats smart
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14:31 | se6astian | so you can switch filters and not need to change the shims
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14:44 | anuejn | so what is the thickness of air from the sensor to outer sourface of cp?
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14:44 | anuejn | also why is the shim thicker and not thinner?
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14:45 | anuejn | not the shim, the filter holder
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14:56 | se6astian | <anuejn> so what is the thickness of air from the sensor to outer sourface of cp? <- 4.75mm
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14:56 | se6astian | <anuejn> also why is the shim thicker and not thinner? <- did we make a mistake with the calculation?
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14:56 | anuejn | Idk maybe my intuition is wrong
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14:57 | se6astian | https://www.spektrum.de/lexikon/optik/planflaechenabbildung/2588
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14:57 | anuejn | vup: what do you think
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14:58 | anuejn | ok no seems to be correct
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14:59 | se6astian | please double check
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14:59 | anuejn | so a lens mount needs to have the thickness of d=(Flange distance)-(4.75mm-2mm-2mm-0.15mm)
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14:59 | anuejn | so (flange distance)-8.9mm
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15:00 | se6astian | yes that looks correct
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15:02 | anuejn | nice :)
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15:03 | se6astian | what do you plan to build?
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16:05 | anuejn | just some general investigation into lensmounts again
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16:06 | anuejn | prompted by https://chaos.social/@*email address removed*/111723474237278079
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16:29 | se6astian | great
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