One interesting part of astro imaging the Moon is image scale. With telescope and iPhone camera, which has two camera lenses, one can choose a 1x wide angle lens, 2x telephoto lens or simply vary the EP and FR lens combinations.
Be sure to move the camera to center the Moon relative to the axis of the lens used. This method is afocal. This method works well and even by introducing an additional 6 lenses into the optical train, any reflections are eliminated by camera position.The quick and dirty examples are shown to demonstrate image scale, taken without a camera mount and without a lunar drive to follow the Moon. The curvature at the bottom of the moon is caused by the restrictive FOV and gives an idea of image scale. Both images are taken with an iPhone XS Max, March 27th, 2019 up to 1am local time.
The first image is 1/79th second exposure. The second image is captured with the same 4.25mm F1.8 lens at ISO400 and 1/40th second exposure. The image scale was converted by the changing configurations of EP and FR. When a camera mount and drive are used, the image scale can be increased dramatically by eliminating the FR and selecting a different EP of shorter FL. Tracking will allow still greater EFL and the use of a 2x or greater Barlow lens. A 14-inch Celestron EdgeHD telescope was used for all experiments during hazy and cloudy conditions. IP compensation removed light pollution, fog, haze and clouds. The first image is converted to BW while the second image shows color through haze - in both instances the Moon showed the effects of atmospheric dispersion being relatively close to the horizon. The telescope was indoors shooting through an R Sky Zone which can be seen at the links.
Indoor Observing Links
https://space1usa.blogspot.com/2019/03/space1-singularity-observatory-indoor.html
https://space1usa.blogspot.com/2019/03/space1-singularity-observatory_20.html
