I do that sometimes because I'm sensitive to light, so I can get a better look at something.
If you're talking about in a medium to subdued light situation, I'll look at one aspect of something to be able to enjoy that particular aspect.
Take for example, something truly interesting--watching a train leave. Most people have seen this, but if it's something you really enjoy, you want to really
see it, not just look at it. You want to have a little knowledge of it, to know what is going on--to add a few extra dimensions to the appreciation of a train.
First off, it's never "just a train." In this case it was SY-class #3025 on the Valley Railroad. Fascinating locomotive--built from a Chinese freight locomotive into a hybrid of SY class and New Haven practice. Steam locomotives in the United States are usually painted a plain black but they are still going to have fascinating details. Up close, just an absolutely beautiful locomotive--design philosophy from 1920s American practice, built in a Chinese plant in 1989 during the twilight of the steam era, sold to American operators in Tennessee, destroyed in an engine-house arson attack on the Knox & Kane in 2008, and rebuilt in Connecticut with parts and design cues from the extinct New Haven Mikados, all making one of the more unique locomotives you will see. As a completely hand-fired engine (no mechanical stoker) it is one of the fewer medium-sized locomotives you will see set up like that, and the 2-8-2 wheel arrangement is just good looking overall, with the trailing axle under the cab to support the weight of a full-sized firebox. It's enough to let you get a lot more power and range out of an eight-coupled design. Mikados and the old 2-8-0 Consolidation class locomotives are about the perfect type to run on heritage railroads, and they can pull plenty if needed while still being smaller and easier to keep going.
Here's a picture I took when I got stuck at a railroad crossing.
You walk across the tracks and the engine is waiting at the station--the fireman is doing a walk-around inspection and oiling the rods, making sure the fire is hot but not so hot as to cause the safety-valve to pop off. Over-firing an engine wastes coal and water, and it's loud and looks a bit ridiculous. There is a certain amount of style, of panache, to operating live steam. It is a carefully controlled finesse of elemental forces of nature: the "iron horse" is best ridden in dressage classes.
Just the lighting and electrical system of a steam locomotive are a fascinating thing to see and hear and watch in action: Pyle dynamos, a species of small turbine to power the electrical system, always have a unique sound spooling up--humming, irritating whining from the dynamo turning, hiss of steam escaping at the top of the narrow pipe near the generator. You can see the dynamo on #3025 in that photo, near the beginning of the cab roof. When that starts, the headlight will make a faint
clink and begin glowing--first dimly, then brighter and brighter--if you look at it from the side it looks about like a standard household light bulb; stand in front and the reflector throws a single condensed beam of light.
The engineer and the fireman climb their stairs and are back in the cab--the fireman is a chubby girl in overalls with blue hair, tall as a man; apparently Generation Z is preparing to fall heir to the world of infrastructure. Engineer Lewis looks like the prototype of a railroad engineer--filthy blue overalls and holes burned in his hat, skin looks like his driving gloves, eyes creased into a permanent wrinkled fold from leaning out of the cab of too many locomotives over too many years. Some men retire into a recliner, but he seems to have chosen to retire to the right-hand side of an engine--either steam or old 1940s diesels.
Even just sitting still this is worth seeing, and there is really no "glance once" way to see a locomotive--you need to get a good look at the
whole thing, so you run back away from the edge of the line when the whistle blows so you can watch the train leave. It is not so much a departure as it is a performance, a ritual. The drain-cocks open at the bottom of the cylinders--the front of the engine is shrouded in a sudden rush of white vapor, and very slowly the side rods begin to turn the wheels. You get the impression that it is possessed of a powerful force not entirely mechanical, something that is working the cranks on the driving wheels much like you would push the pedals of a bicycle. Water is flying everywhere and the engine creeps forward for a few yards, then, with the cylinders preheated, the driver closes the drain-cocks and advances the Johnson bar in the cab. The sound changes from the hissing breathing to a deeper note like the low pedals on a theatre-organ, and everything moves all at once. The ground begins to throb with each exhaust beat, the chimney is throwing a steady fountain of hot-water spray and cinders, and the slack between the cars starts to take up--bang, bang, bang, all the rest of the way down until the observation platform at the very last car shakes and the crossties begin to walk away from underneath. Cold weather means the heat is on in the cars--escaping from hoses and fittings at each coupling, the white lifebreath of the engine is running a set of iron radiators along the baseboards, keeping passengers from getting too cold in a New England winter.
No one is going to run anything fast on that stretch of rail; the tracks crossing Main Street are dated to 1893 along the sides of them and it's a rough patch going out of the yard. The start-up is over, the train is moving, and the hunched olive-green rooftops of the cars follow a black wraith of coal-smoke into the woods until the last car with its red tail-light is gone off into the bushes, and the thump-thump-thump of the engine picks up its pace as it disappears. You dig a few cinders out of your eye, look down at your camera, and realize you have forgotten to take a picture--but you have
seen the train, and that is what matters. As you turn to go home you begin to think that maybe coming back again to watch the next one leave won't be that bad either, but there is a colorful eighty-ton General Electric on a sidetrack, both motors idling, and you realize that you never really watched a Diesel engine that closely either. Maybe you never really saw one for what it was.
As you leave you hear the train whistling for a grade-crossing further on down the line, and decide that it will certainly be worth seeing again. Maybe next time you'll bring a camera.
Why do autistic people (and cinematographers, painters, sculptors, artists) look at something with their hands like that? For me it was about "composing the shot" in my mind's eye--about getting to enjoy one little aspect of something, then throw it in with a mental montage of the whole thing. Sometimes, you just want to enjoy the experience in all its intensity without overdoing it and taking the whole thing in all at once.
