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  1. Re: Making DIY aperture scale for Prontor Prof. Sshutter

    I have had similar problems when using old shutters from 120 bellows cameras with homemade lenses on a 4x5 camera. The aperture readings of the shutters bears no resemblance to the amount of light...
  2. Re: Fresnel lenses and ground glass focusing screens your worries answered

    Excellent article especially the "light spreading screen" definition.

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  3. Re: Fresnel lenses and ground glass focusing screens your worries answered

    Sent from my SM-T210 using Tapatalk
  4. Re: Fresnel lenses and ground glass focusing screens your worries answered

    There are obviously many factors in fresnel lens placement that I have failed to understand. Could someone explain to me that if a fresnel lens has to have a focal length related to the focal length...
  5. Re: Fresnel lenses and ground glass focusing screens your worries answered

    I hope this helps to clear up some confusion

    The total cost of this project was about $5 and two hours work. As an added bonus it annoyed the...
  6. Re: Fresnel lenses and ground glass focusing screens your worries answered

    I absolutely understand that the frosted side of the ground glass screen must be exactly at the film plane. If you place the fresnel lens flat onto this frosted side of the ground glass screen...
  7. Fresnel lenses and ground glass focusing screens your worries answered

    There has been a lot of chat and controversy about the use of fresnel lenses in combination with the ground glass on large format cameras in attempt to brighten the image formed on the screen thus...
  8. Re: Creating lens aperture scales - what a project!

    I have had similar problems calculating f stop values on homemade lenses mated to old canibalised shutters from vintage bellows cameras. I made a through the lens meter which has solved these...
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    Re: Tension springs

    I use car windscreen wiper springs

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  10. Re: DIY: tape measure for easy bellows extension calculations

    Have a look at the through the lens meter on this site, all your bellows factors will be resolved at a stroke

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  11. Re: Need some help cutting spring tempered steel!

    I use windscreen wiper springs

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  12. Re: Calculating, NOT measuring, aperture of compound lenses

    What you need is a through the lens meter to provide you with the data required. There is one on this site.

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  13. Replies
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    Re: spring steel for camera back?

    I use car windscreen wiper springs


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  14. Thread: springs

    by john.l.barford
    Replies
    8
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    4,285

    Re: springs

    I use the springs from car windscreen wipers

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    6,292

    Re: ULF build with extruded T-channel?

    Ihave built a 4x5 camera with MAKERBEAMhttps://uploads.tapatalk-cdn.com/20170711/b8ef948ddfde9eb2c85554e522bb131c.jpg

    Sent from my SM-T210 using Tapatalk
  16. Replies
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    6,292

    Re: ULF build with extruded T-channel?

    I have built a 4x5 camera with MAKERBEAMhttps://uploads.tapatalk-cdn.com/20170711/8012d5ff78d553f75a32c54a33c587de.jpg

    Sent from my SM-T210 using Tapatalk
  17. Replies
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    7,735

    Re: Through the lens metering

    When i first started messing about with the idea of building a through the lens meter the reasons for it were to more fully understand the effects of bellows extension on exposure, the effects of...
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    Re: Through the lens metering

    On the subject of spot or average meter readings with the through the lens meter.
    I have explored the idea of placing lots of small solar cells in patterns then activating some of them and...
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    7,735

    Re: Through the lens metering

    To calibrate the through the lens meter
    I suggest that at first you use the lux meter
    (before you chop off the end) and print out a LUX to EV conversion table from the net. Use the lux meter...
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    Re: Through the lens metering

    It is able tto cover all exposure values (EVs) from 1 to 16

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  21. Replies
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    7,735

    Re: Through the lens metering

    Through the lens metering .
    To make this meter you will need.
    1) A LUX METER. Plenty of these on e bay. You will need one where the sensor head is seperate from the meter joined to it by curled...
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    Re: Through the lens metering

    I am seriously unimpressed with tapatalk

    Sent from my SM-T210 using Tapatalk
  23. Replies
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    7,735

    Re: Through the lens metering

    Tapatalk appears to only accept one photo at a time

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  24. Replies
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    7,735

    Re: Through the lens metering

    Makerbeam camera

    https://uploads.tapatalk-cdn.com/20170705/104a151bdeeb1c3748789e315ee0441c.jpg

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  25. Replies
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    7,735

    Re: Through the lens metering

    I am having diffulculty downlooading pictures

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  26. Replies
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    Through the lens metering

    I have made a 4x5 camera using aluminium extrusions called makerbeam. I have bought one 150mm 4x5 lens and have made a couple more using binocular objective lenses and old prontor shutters from...
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