Getting the exposure right while juggling the three camera controls ISO, aperture and exposure time can be tricky. Calling it the exposure triangle is not very helpful because it doesn't tell you how to trade one off the other. In this double sized extended cheatsheet, a scale full of three kinds of tuna (representing ISO, aperture and exposure time) shows various combos can give the same weight (representing exposure).
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Photographing the 2017 solar eclipse: solar prominence (loops off the surface of sun) and corona., Also a “diamond ring” shot.
Read MoreI followed the suggestions in the website http://richardsont.people.cofc.edu/safe_solar_folder/ with a +2 diopter close-up filter as my first lens and a mystery -25mm (??) lens as my second one, using a shelving upright as an optics rail.
Pro: You get a nice big 2-3″ image for everyone to look at. It is fun to rearrange as the sun moves in the sky. You can photograph the projection with any kind of camera.
Con: It is kind of fuzzy. If blown up to larger sizes, you get one edge blue and the other red due to chromatic aberration. You can spend more for non-aberration lenses.
Upshot: A great interactive group activity.
"Pin holes" can be using found from boards, fingers, Venetian blinds, trees, etc. The further away, the bigger the image.
Eclipse projection from pinholes (very faint), 3/8″ holes and fingers criss-crossed.
Eclipse projection from Venetian blinds.
Eclipse projections from ~25 ft high live and ~80 ft high dead (and needle free) Balsam pine trees in British Columbia, Canada. Man’s sandals at bottom for scale. [Anonymous]
Pro: Size of image can be much better than with shoe box camera because distance is further. Compare images from different hole sizes. Multiple holes make fun effects.
Con: You might forget to look and find them!
A pin hole camera made from shoe box is frequently recommended as a safe way to view a partial eclipse.
Pro: Probably couldn’t hurt you if you ate it. Can get images of surrounding wispy clouds.
Con: Image is very tiny. Awkward to photograph. Thrown in a corner and ignored, so no photo.
But if you think bigger, much bigger, the concept can be pretty fun. See a following blog entry on found objects.
Partial eclipse viewing: Firecrest 18 Stop Neutral Density Solar Filter from the U.K.
Pro: Nice neutral color. Was in stock at B&H when others were out.
Con: Oh boy. I neglected to try this out on a non-eclipse day and didn’t debug a number of problems, maybe not due to the filter per se.
Cyan colored lens flare. Duh.
Hazy lens flare.
Double image— kind of like what you see if you have cataracts.
Curious: Why is the cyan lens flare image rotated 180 degrees from the main image? Why does the main image of the eclipse look like a banana? [see bottom tip of the crescent]
Upshot: The solar eclipse filter was disappointing.
Update: Photo was very overexposed. I suggest practicing ahead of time by photographing sun spots.
