When You Are Satisfied With The Result, Go To The Press.
As exposure time? This is a big problem because the exposure time varies from card to card. the best thing to do is “try the photo paper,” sacrificing a sheet.
The procedure is very simple:
cover the entire sheet of paper with a card that does not let light through.
discover a portion of the paper, say a sixth (1/6) of the size.
after 5 seconds, discover a second sixth (2/6), and so on, 5 seconds in 5 seconds.
after 30 seconds, turn off the magnifier. Possibly remember you install a blower and use the switch of the enlarger, otherwise the risk of camera shake.
Your sheet will be a set of different exposures (six to be precise) that vary from 5 (the last piece discovered) to 30 seconds (the first piece) with multiples of 5 seconds. Analyzing the paper will be able to define the time that, in terms of exposure, the better the response.
Also remember that if you change the aperture http://smilesmultimedia.com, we will modify the exposure time: a stop in less translates into a doubling of the exposure time and vice versa. Different speech for the filters: the filters numbered 1 to 3 (the gradation) do not affect the time, while a gradation filter 4 is equal to a stop in less and thus serves the doubling of the exposure time.
Once you have identified the correct exposure time, we move to phase our negative exposure.
Positioning of the sheet. This process is not easy: the paper polietinata tends to be slightly bent while the fiber paper, during the exhibition shrivels. Get yourself an easel or realizzatene one: just a frame created with pieces of plastic (found at Leroy Merlin a few cents) to be placed on the edges of the card (do you remember the white part of the photograph, the edges?).
Exposure. Place the magnifier filter (if necessary). Light the lamp. Count the time exposure, turn off the lamp.
Finished, it’s time to move to the final phase of development with three bathrooms in sequence.
Take your paper with tweezers (never with the hands) and dip it in the solution development. Do not hesitate, “drown it” quickly so that it is soon covered by the solution.
In the case of paper are sufficient polietinata 60 seconds of the bathroom, in the case baryta paper about 2 minutes. With tweezers dedicated to developing solution (not mix them!), Pull the paper away, drain them and immerse in the stop solution.