Roger Cambell Posted May 11, 2016 Share Posted May 11, 2016 Hello everybody.My name is Rogers and this is my first time posting on Cinematography.comToday for a school project I attempted developing Kodak Tri-X 7266 with a Fomapan R100 Kit in a lomo tank. I followed the instructions yet the project did not work well. It appears as if the whole emulsion was removed from the base of the film leaving it clear. My problem is I can't figure out at what step this happened. Would someone have any information on what could have caused this to happen? Perhaps it was during bleaching something went wrong? Also, it would be nice to understand the re-exposure part a little bit more. This was my first time so I was expecting some chaos.Thank for reading my post and to anyone who can spare some info! Link to comment Share on other sites More sharing options...
Richard Tuohy Posted May 11, 2016 Share Posted May 11, 2016 How did the film look during reexposure? Assuming the chemistry was all mixed correctly, then clear film could be caused by forgetting to redevelop (or using the wrong chemical) or forgetting to reexpose. Link to comment Share on other sites More sharing options...
Roger Cambell Posted May 12, 2016 Author Share Posted May 12, 2016 How did the film look during reexposure? Assuming the chemistry was all mixed correctly, then clear film could be caused by forgetting to redevelop (or using the wrong chemical) or forgetting to reexpose. Thank you very much for your response Richard Tuohy! I want to ask you more about the re-exposure part because that is where I may have messed up. What exactly are you supposed to do? Perhaps I did use the wrong chemical, I followed the instructions given in the kit. I just can't figure out where I went wrong I am going to the lab today to try again. Thank you! Link to comment Share on other sites More sharing options...
Richard Tuohy Posted May 13, 2016 Share Posted May 13, 2016 Re-exposure is very simple. The simplest thing to do is to take the film out of the lomo tank (still on the spiral) and walk outside with it for a few minutes. That works. Normally, I do the re-exposure in the dark room using a 100 watt lamp. I wave the spiral around under the lamp for a couple of minutes. You can't get it wrong really. Here is how the reversal process works. I assume you are comfortable with the idea that when you put film in developer you create a negative - ie on the film you will have black in areas that were hit by light and clear where there was no light hitting the film. Okey, so with the reversal process, you start with developing a negative. This is the first developer stage. Note that while various instructions will provide you with time and temperature recommendations for all the various steps of the process, it is only this first developer step where time and temperature really matter. With all other steps - including re-exposure - there is a minimum amount of time required to complete the step, but no maximum. You can't really do any of the other steps too long. They are all simply done 'to completion'. Once the step is complete, staying longer in that step doesn't matter. Okey, so first you develop a negative. If there is a negative on the film, then in some sense you can say that 'everything else' on the film 'would' make a positive. So, next step is to bleach away that developed negative. Bleach bleach bleach. You have bleached out the developed metalic silver - the black stuff that makes the negative image. Left on the film is silver halide - basically raw emulsion. This, I like to say, is in the 'shape' of a positive. Pour developer on it at this stage, however, and nothing will happen. This is because silver halide (the stuff of raw photographic emulsion) needs to be exposed to light in order to develop. If you don't expose to light (the re-exposure stage) then no image will develop. It will just remain silver halide. So, you have to re-expose. Turn the lights on! Now, develop for the second time. This will turn the exposed remaining silver halide into metalic silver. Presto - a positive image. There are two other baths in the reversal process, but only these three are really doing photographic work. The clearing bath which comes after the bleach is simply there to remove a stain caused by the chemicals in the bleach. The fixing stage, with occurs after the second developer is there simply to get rid of any silver halide that is 'dead' - that is, silver halide that for whatever reason didn't develop in the first developer or the second developer. There are always some dead grains of silver halide. Fixer dissolves silver halide. But in the case of reversal processing you can't really see it do its work because virtually all of the silver halide on the film was developed in either the first or second developer. so, clear film after the reversal process means: - you didn't re expose - you didn't second develop or you used the fixer before you did the second develop. cheers, richard 1 Link to comment Share on other sites More sharing options...
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