Originally Posted by
salvatore
Hi Nana Dadzie,
A few words on the progress of my project.
I bought a 19" Artar red dot lens and build a primitive camera mounting such lens.
A computer screen was projected (1 to 1) on a radiographic Fuji green film and developed with HC110 1:50 for 10 minutes.
I could not get a large optical density, even by extending exposure time.
By inspecting the negative with a magnifier I could clearly detect the single pixels, and I understood why I was limited in o.d.
Since the film is sensitive only to green (and perhaps a little to blue, but not to red), only a part of the pixel impresses the film.
Actually, the transmission of the impressed film could range from 66%(only green) to 33%(green and blue), and even more, considering the inactive part of the pixel.
This means an o.d. of 0.5 to 0.18, a very poor result.
Such a situation is very bad for the direct production of a negative, and acceptable to produce an intermediate positive to contact print to get the desired negative.
To overcome this problem (I do not like to need two films) I plan to build a device which moves the image up down and left right to the extent of a pixel (about 0.2 mm) to impress homogenously the whole pixel with the green one.
If it works fine I will describe it in detail.
Does anybody know of a similar approach?
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