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Thread: USAF-1951 drum scanned?

  1. #1

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    USAF-1951 drum scanned?

    While I've seen a lot of scans of the USAF-1951 test target from the flatbeds, I'm yet to see any drum scanned. Is there any?

    PS. Of cause I'm ready to read that I do not need it and final print is the only thing that counts.

    Best wishes
    Al

  2. #2
    8x10, 5x7, 4x5, et al Leigh's Avatar
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    Re: USAF-1951 drum scanned?

    High-quality resolution targets are usually chrome on glass.

    They don't bend around a drum.

    - Leigh
    If you believe you can, or you believe you can't... you're right.

  3. #3

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    Re: USAF-1951 drum scanned?

    I heard they produce targets on Film to. It looks you are right: it is hard to find one on a film.

    Below is not USAF-1951. It is a rooler for microscope. On a glass. One step is 0.01 mm and made of white and black. So we see 200 different color steps per mm. That makes resolution 5080 dpi and it is resolved by Eversmart Pro. One can read also the numbers.

    Click image for larger version. 

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  4. #4

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    Re: USAF-1951 drum scanned?

    If you have a high resolution chrome on glass target, and a small contact printing frame, you could contact print it on high resolution film. For sharpest results use a point light source at 8-10 feet from the frame.

    The Eversmart Pro has theoretical optical resolution of 3175 spi X 8200 spi. The higher resolution is in the direction of the movement of the CCD. If you scan at more than 3175 spi there will be some interpolation involved.

    Image quality with the Eversmart Pro is on par with a Howtek 4000/4500 scanner. The only down side of the Pro is that you are limited to 8 bit saves. The actual analog to digital conversion is made in high bit (14 bit ) but the file is saved as 8 bit. My work flow with B&W is to scan in RGB, then immediately convert the saved file to 16 bit grayscale before doing any image processing.

    Sandy King
    For discussion and information about carbon transfer please visit the carbon group at groups.io
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    Re: USAF-1951 drum scanned?

    Quote Originally Posted by sanking View Post
    If you have a high resolution chrome on glass target, and a small contact printing frame, you could contact print it on high resolution film. For sharpest results use a point light source at 8-10 feet from the frame.
    And I finally did it some years ago. I used imagesetter film and managed to contact copy all the fields (up to 7.6).

  6. #6

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    Re: USAF-1951 drum scanned?

    Quote Originally Posted by SURF View Post
    And I finally did it some years ago. I used imagesetter film and managed to contact copy all the fields (up to 7.6).
    This is 5 years later !

    7.6 is 228 lppmm, if the drum could see 7.6 then this is more than effective 12000 dpi. Some drums were advertised at even 11000 dpi, but reaching in practice way less effective performance, perhaps 6000.

    Not a drum, but X5 reaches 6500 dpi with small format film, much less as scan row is wider. So I guess that a 7.6 target should be fine...


    http://www.filmscanner.info/en/Hasse...extightX5.html

  7. #7

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    Re: USAF-1951 drum scanned?

    One can now purchase a high resolution target on film for use on drum scanners.

    http://www.silverfast.com/show/resol...target/en.html

    Sandy
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  8. #8
    Pali K Pali K's Avatar
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    Re: USAF-1951 drum scanned?

    This is a dry mount test on Heidelberg Tango.


  9. #9

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    Re: USAF-1951 drum scanned?

    Quote Originally Posted by Pali K View Post
    This is a dry mount test on Heidelberg Tango.
    It looks 6.5 element, so 101.6 lp/mm, 5161 dpi if using "filmscanner" criterion... http://www.filmscanner.info/es/Aufloesung.html

    If we consider 6.4 then it is 4598dpi...

  10. #10
    Pali K Pali K's Avatar
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    Re: USAF-1951 drum scanned?

    I agree Pere. Tango is around 4500-5500 DPI depending on the condition of the optical path. My Scanmate 11000 which is rated at 11000 DPI also is around 8000 DPI based on a similar test.

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