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Thread: Need Guidance on Getting a Sensitometer

  1. #21

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    Re: Need Guidance on Getting a Sensitometer

    Very helpful for sure. Thank you!

    Quote Originally Posted by ic-racer View Post
    In addition to the information provided by Greg above, you might find these threads useful:

    https://www.photrio.com/forum/thread...e-soon.175464/
    https://www.photrio.com/forum/thread...hootout.95837/

  2. #22

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    Re: Need Guidance on Getting a Sensitometer

    Hi, I want to make sure I am clear on a point that you made in the first link below.

    Are you saying that the blue and green LED sensitometers that are readily available today which were designed for Radiographic work I believe are sufficient for testing B&W 35mm roll films for the range of sensitometry tests as outlined in Kodak's "Basic Photographic Sensitometry Workbook"?


    Quote Originally Posted by ic-racer View Post
    In addition to the information provided by Greg above, you might find these threads useful:

    https://www.photrio.com/forum/thread...e-soon.175464/
    https://www.photrio.com/forum/thread...hootout.95837/

  3. #23

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    Re: Need Guidance on Getting a Sensitometer

    Quote Originally Posted by LFLarry View Post
    Hi Luis, I had a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
    If you want to test film for speed and developing time, I use a densitometer, NOT a sensitometer.

  4. #24

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    Re: Need Guidance on Getting a Sensitometer

    Hi Luis, I understand and agree with you. I am talking about using a sensitometer for creating a characteristic curve, determining D-min/D-max, Contrast Index, and exposure latitude. Basically, all the sensitometry "stuff". I have a solid process already in place with my densitometer only where I can accurately determine the EI rating for any film and developer combo as well as the associated development times for N, N+, N-, etc.

    My goal with the sensitometer in conjunction with the densitometer is to really compare same films in different developers and various films in the same developer to ultimately meet my personal creative vision.

    While the exposure part can be done with an enlarger and electronic timer, a sensitometer just makes that part of the process fast, painless, and easy with 35mm roll film. I also think it is more consistent than using an enlarger too.

    Quote Originally Posted by Luis-F-S View Post
    If you want to test film for speed and developing time, I use a densitometer, NOT a sensitometer.

  5. #25

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    Re: Need Guidance on Getting a Sensitometer

    I don't know of any consumer-grade sensitometers being made today. When I worked for Eastman Kodak, my division designed, built, and sold a few of the Model 1-B sensitometer. It was used to characterize aerial camera and duplicating films, and create control strips for the various specialized processes used. I believe we supplied a few 1-Bs to other Kodak divisions, as well as the U.S. government. It was also about the size of a home washer-drier combo, and the price must have been quite substantial (as in if you have to ask...). Of course if you're a manufacturer selling hundreds of million dollars worth of quality product, you'd need something like that. Oddly enough, my first assignment at EK, in 1984, was to make photographs of that machine for an upgraded instruction manual.
    I'll guess that any of the various home-made devices mentioned above will serve your purposes quite well.

  6. #26
    Tin Can's Avatar
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    Re: Need Guidance on Getting a Sensitometer

    I have no idea if these are worth buying, but there are 50 FS

    I think they were used for Mammogram X-Ray which was the last of the analog uses in NA

    https://www.ebay.com/sch/i.html?_fro...R+SENSITOMETER
    Tin Can

  7. #27
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    Re: Need Guidance on Getting a Sensitometer

    Tin Can

  8. #28
    ic-racer's Avatar
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    Re: Need Guidance on Getting a Sensitometer

    Quote Originally Posted by LFLarry View Post
    Hi, I want to make sure I am clear on a point that you made in the first link below.

    Are you saying that the blue and green LED sensitometers that are readily available today which were designed for Radiographic work I believe are sufficient for testing B&W 35mm roll films for the range of sensitometry tests as outlined in Kodak's "Basic Photographic Sensitometry Workbook"?
    LED sensitometers work fine for comparative testing most black and white panchromatic films. Analogy is a 'balance' where you have to place objects on both dishes to compare things.

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  9. #29

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    Re: Need Guidance on Getting a Sensitometer

    Just watched it Greg. I gave it a thumbs up and commented and posted a question for you too (Stealth Van Life is my YouTube handle).


    Quote Originally Posted by Greg Davis View Post
    New video in the series, Contrast Index: https://youtu.be/TwTymRBedz4

  10. #30

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    Re: Need Guidance on Getting a Sensitometer

    Randy, the issue with the X-Rite densitometers is they don't publish the exposure time or the illuminance value of the light source, both of which are needed to build characteristic curves. Based on the info from IC-Race, the Blue & Green LED units will work for B/W film exposure. I wonder if the exposure time and illumination value is provided with the calibration data?


    Quote Originally Posted by Tin Can View Post
    I have no idea if these are worth buying, but there are 50 FS

    I think they were used for Mammogram X-Ray which was the last of the analog uses in NA

    https://www.ebay.com/sch/i.html?_fro...R+SENSITOMETER

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