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    The Adventure of a 21st Century TOV Photo
    From: Marcel Tschudin
    Date: 2012 Jun 6, 12:56 +0300
    Sorry, did before hit the send button by mistake. Here comes now the complete story.


    In 2004 I had the chance to watch the TOV event in the office through the window. With one of those cardboard "glasses" used for watching a sun eclipse I could indeed see the fly spot Venus gradually progressing across the sun disc.

    Now 8 years later, being at a different part of the world offered again the possibility to view it. This time I aimed however at taking a photo of it. It appears that this event received not much attention in Turkey, at least the opticians did not have those cardboard "glasses" which I tried to obtain to put its material in front of my lens. On ebay such cardboard "glasses" were available, but only in larger quantities which would have required to be sent from abroad as a small parcel. Receiving a small parcel from abroad in this country? No! Never! Previous experience showed that that custom clearance for "ridiculous" items turns out to be horror, requiring a full day of travelling to the authority in charge and there being sent from one office to the other, each time lining up to receive some stamps and pay some fees. To get some parcel from abroad became therefore a no go.

    While being in off-list contact with Greg regarding his Bris the subject turned also on the coming TOV event. When I explained him my situation, Greg offered me to sent in a letter some his solar film. On May 30 he sent the letter, but would it arrive in time? Experience has shown that letters from abroad (US and Europe) take something between about 5 days and 5 weeks to arrive here, not to mention those sending which never arrived.

    In the morning of June 5, a day before the TOV event, the letter has not yet arrived. I therefore started to find some alternative solutions. Which material could dim the sun sufficiently without completely blocking its light? And, how would I have to set my camera which only has a selection of "scenes" and no individual settings of exposure time and aperture. The "sport" setting was considered likely to be appropriate because it favours a short exposure time. An additional option allowed to reduce the EV value by up to two units. First I tried with some aluminised(?) paper from inside a cigarette box this blocked the light completely. A sheet of normal white paper also blocked the sun light completely. Trying without any protection was overexposed with fastest exposure time of 1/2000 s. Later I had the idea to use the coloured plastic package of paper handkerchiefs the image was again much overexposed. Then I tried with the plastic of a strong shopping bag, the image was better but still overexposed. It looked however like it could go with additional layers of this material. With two layers it was still overexposed. When I tried to add a third layer my wife came and told me that a letter from the US arrived! Since it was already late afternoon I changed for further testing immediately to the solar film. Doing several trials showed that the dark film leads to very long exposure time and thus overexposing the sun image. By manual setting it was possible to limit it to 1/8 s.This was still too long. By activating the flash(!) it was possible to reduce the exposure time to 1/30 s. The images were still far from being ideal but it was about the best I could obtain from the tests. Greg suggested to hold the film at some distance in front of the lens, but it became too late for testing this option; may be I would have a chance to test it during the TOV event itself.

    From CalSky I learned that the TOV event will be visible here from sunrise at about 4:30am until shortly before 8am. I thought to go to bed early in order to wake up early. That was the intention, but later we received a telephone that we would get some visitors staying over night. Nothing from going to bed early. During the night we had a thunder storm. How will the weather be tomorrow? At 1 am I decided to set the clock for 5:30 am waking finally up 15 min earlier. The sky looked mostly clear, so I gave it a try. Well at home the sun appears only later during the morning. I started to search my place of observation which I found at a bus stop. It had the advantage that I could sit and control the camera on the tripod in fron of me. At the beginning the sky was indeed mostly clear. With the time more and more clouds turned up. From about 7 am onwards the sun was completely covered. I waited and waited but it did not appear again.

    At home I looked at my shots. A first look indicated nothing to be useful. Looking again at them I found finally one of the 12 photos which appears to show Venus... Could it be that some thin clouds helped to get an approximate feasable exposure?

    That's my story. It takes now a while until someone else has a story on the next TOV event.


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