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Re: [APML] May Lunar eclipse camera?
Scott writes:
> My
> problem is my current cameras don’t offer the ability to shoot the same
> frame multiple times...
Hey Scott... I recall you're using Canon equipment. My FTb QL manual instructs
that you push the canister release button, turn the rewind crank 7/8 of a turn,
then turn the film advance/shutter reset lever... without holding the release
button, of course. This is inaccurate as far as this type of Eclpise
photography goes. You can get some decent double-exposures this way... see:
http://home.att.net/~astropix/Down_Town_Double_X.html
... but not the precision desired for the shot you seek. 'Hat Trick' it! Here's
how: First, get to the darkest location that's practical for you. Ambient light
will quickly fog the film with this technique. Next, carefully place the camera
in the position it will be in for the duration of the exposures. Probably best
to do some dress rehearsals with the selected equipment in the nites preceding
the actual event.
Begin the first exposure by covering the aperture with a black card and
locking the shutter release cable in the bulb position. (you will leave the
shutter locked on bulb the entire time) Remove the card to effect the exposure.
Cover the aperture at the end of the exposure with the card once again,
then :::install the lens cap::: to wait for the next exposure time. Remove the
lens cap several seconds before time for each exposure to allow vibrations to
dampen... remember to have the card in front of the lens before removing the
cap!
I have two different black cards I made from black foam-core. One will
cover the front of my C-8. I used a large wooden paint paddle (for 5 gallon
buckets) super-glued to the foam square as a handle. The smaller, camera lens
sized one has a foam-core handle... I even added a piece of black twine as
a 'strap' to the small one so it can hang from my wrist while I fiddle with
other things! I painted a light coat of ultra-flat black to the business end of
things. These have worked very well for me... I don't bother with mirror lock-
up on my deep sky shots anymore... I lock the cable with black card in front of
the scope... count 3 for things to dampen... and begin my exposure by removing
the card from in front of the aperture. I end my exposures in reverse... block
the aperture, then release the cable lock.
Covington has very good recomendations on exposure times and field of
view. I'd refer you there for lens selection. He's a mathematician... I'm just
a mechanic... :O)
Hope This Helps...
Geoff
--
http://home.att.net/~astropix/
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