On the night of Oct 23/24, 2020, RIT capstone student Vince Iglesias-Cardinale and I practiced taking pictures of the Moon with various combinations of telescopes and cameras. We hope to acquire simultaneous images of the Moon from two different locations in the future, in order to measure the Moon's parallax.
We were joined by Jennifer O., a member of the Rochester community, who was hoping to take pictures of the Moon herself.
All three of us tried using several small telescopes, together with smartphones attached to the telescopes via a special bracket. The eyepiece projection provided a nice, big image of the Moon, but focusing and centering it was a challenge. Jennifer picked a couple of her images and sent them to me. The blue color is due to a filter we used to cut down on the brightness of the lunar surface.
I used a Nikon D50 and 300mm f/4.5 lens mounted on a tripod to take images as well. My notes from the night are shown below.
Images taken Oct 23, 2020, at RIT Observatory.
- Moon at age 7.8 days, at First Quarter
- skies clear
- using Nikon D50 and Nikkor 300mm f/4.5 lens, on tripod
- ISO 1600 setting
- pressed shutter release with finger, rather than using remote
- Moon spans 355 pixels = 30:55 arcmin = 1855 arcsec -> 5.2 arcsec/pixel
- field of view 3008 x 2000 pixels = 4.4 x 2.9 degrees
- lens set at f/4.5
- images taken around 7 PM local time (EDT)
even shortest exposure of 1/250 saturates most of the illuminated
portion of the Moon
1-sec exptime shows blooming of illuminated portion of Moon,
but can see clearly stars of mag 6-7 at > 0.7 degrees from Moon
stellar images are round, no trailing
5-sec exptime shows trailing of approx 10 pixel East-West
can see stars of mag 8; mag 9 are very faint, but visible
- lens set at f/5.6
again, 1/250 sec saturates most of illuminated portion of Moon
1/10 sec doesn't show even the brightest star
1-sec exptime shows round stars
5-sec exptime shows stars down to mag 9, as before
10-sec exptime shows some stars at mag 10, very faintly
Now switch to Jupiter, time is around 8 PM EDT
- lens at f/5.6
shortest exposure, 1/100, just barely saturates Jupiter
Moons are invisible
1/10 sec shows some moons faintly, looks like double exposure
1-sec exptime shows moons very well: pixel values 100-200 out
of 255, not saturated, but far above sky
10-sec exptime shows stars of mag 10 and 11 (faintly),
considerably trailing
Try doing astrometry. Pick image 401, 1-sec image of Moon.
- in GIMP, convert image to monochrome, save as JPG.
- then run "convert" to turn into FITS (which will be 8-bit version)
- then add const=0, save in outfile to create 16-bit FITS
- Moon is at RA = 20:35:43 Dec = -23:14:08
Last modified 10/25/2020 by MWR.