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Dirk DeJonghe

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Posts posted by Dirk DeJonghe

  1. I have seen many rolls damaged by X-Rays. I am sure any lab can tell you horror stories.

    They look like a pulsating blueish fog. We can even tell if the X-ray exposure was before or after the camera exposure by the increasing rythm of the pulsations. I have one customer with a full carton of 100ft daylight spools; the box must have passed the x-ray machine looking at the short edge. The first two rows of cans were damaged, the second one less than the first one, the X-rays did not penetrate more than two rows of cans.

    The world is a changed place since the war on terror.

    All I can say is that the film is most likely total loss, no easy digital fix.

  2. We still do quite a bit of optical reductions. There are several reasons: the first and most common one is to make 16mm prints from digital files, we cannot record directly to 16 but we make very good quality 16mm direct reductions or via IP/DN. The other reason is to have 16mm prints from either 35mm or S16 originals for loop projection in art installations, the projector is part of the installation in full view of the public.

  3. The current negative films are more easily edge-fogged during loading. There used to be an extra filter layer on the base of the 100ft spool filmstock that was removed about 15 years ago. Always load the "daylight spools" in as little light as possible.

  4. You can use 100' spools on the feed side. You need to remove the core adapter using the small screwdriver that is found inside the feed side of the magazine. You will loose the mechanical footage counter. You cannot use a spool on the take-up side, only a core, so you will have to unload the exposed film in a changing bag or darkroom. Using spools on an Aaton is an emergency solution, not recommended if you can help it.

  5. We have several cinematographers also taking stills on 135 cartridges, Vision3 50D and 500T. We process them in ECN2, as long as the minimum charge of 55€ is covered. Some people bring in 10-15 cartridges, we process and deliver them on a roll. Many decades ago my father started a photographic stills lab, I started doing MP in 1973, processing ME4 for both 16mm and 35mm slides.

  6. We have processed a couple thousand feet of Tri-X reversal as a negative for a school. The grain is very fine, the latitude is much less than Double-X, same as reversal and you loose about one stop of speed. I don't recommend it except as special effect or in emergency.

  7. Several issues here, printing colour negative to B&W stock.

     

    1. normal B&W print stock is orthochromatic, sensitive to blue only, not good for colour negative.

    2. 7222 would be unsuitable due to low gamma (0.65) you need about 2.30.

    3. 7222 has a grey base

    4. most suitable for direct positive print would be sound recording stock such as ST8, still with grey base and non-straight density curve

    5. official way to do Colour negative to B&W print traditionally: make colour intermediate positive, then panchromatic B&W duplicate negative 7234 if you can find it, from there normal prints on B&W print stock.

  8. If you want a simpler explanation, read Appendix 1 'Film Testing Procedures' in Ansel Adams' 'The Negative'.

    He will show you how to do an empirical test to find the practical speed of your emulsion with your exposure meter, your lens and camera setup, and the labs processing.

    Once you have determined the correct film speed (you only need about 5 meters to do this test), then you do the classic keylight test where you start from the speed found in the previous test and search for the limits of over and underexposure. From the previous test you already know that the limit of the shadow detail is at -4 stops by design, you only have to find the limits of overexposure.

    You have control over the shadows with your exposure and 'let the highlights fall' according the the latitude of the filmstock you tested in the keylight test.

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  9. A lab scratch is usually quite easy to identify, the rollers on the processing machine are about 40mm wide and the film gently moves from left to right on the roller. The main culprits for scratches in the processing machine are the squeegees where something may get caught. In this case the scratch will have an easily visible zig-zag pattern. If the scratch is steady and straight, it usually comes from the camera.

  10. If the scratch doesn't move left to right, it is most likely caused in the camera gate. A piece of crud may be touching the emulsion and may cause a pressure scratch, the film is 'exposed' maybe in one emulsion layer only, just by local pressure, there may not be any physical scratch where the emulsion is removed.

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