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| OH Scale |
 Title text: To access distant parts of the project, I ended up building a regular-scale passenger train inside each rail. |
Explanation
This comic references the HO (or H0) scale of 1:87, commonly used for model train sets. Due to a typo, the ratio values were switched by accident, becoming 87:1 meaning the trains, tracks, and all other pieces are 87x the size they would be in real life, resulting in a humorously and improbably large model. To reflect this, or perhaps as part of a similar error, it therefore has been nominally called "OH Scale". "Oh" is also a usual spelling for a common spontaneous expression of surprise, such as might be emitted by someone seeing such a scale model for the first time.
Creating a model at 87 times the real-life dimensions means that you are dealing with tracks and trains the size of skyscrapers. A 'model' train set of this size wouldn't fit in a typical yard and would need planning permission in most jurisdictions. This contrasts with the HO scale trains the protagonist intended to build, which likely would have easily fit in one of the rooms in their house.
| Object | Real world | HO scale | OH scale |
|---|---|---|---|
| Wheel diameter | 1.016 m (40 in) | 11.7 mm (0.46 in) | 88 m (290 feet) |
| Rail height (132 pound main line rail) (from trains.com) | 18.0975 cm (7.125 inch) | 2.08 mm (.083 inch) | 15.74 m (51.7 feet) |
| Rail gauge | 1.436 m (4 ft 8.5 in) | 16.5 mm (0.65 in) | 125 m (410 feet) |
| Typical locomotive (e.g. the EMD F7A) | 15.44 m long, 3.23 m wide, 4.57 m high (50 ft 8 in long, 10 ft 7 in wide, 15 ft high) |
177.5 mm long, 37.1 mm wide, 52.6 mm high (7 in long, 1½ in wide, 2 in high) |
1.343 km long, 281 m wide, 400 m high (0.83 miles long, 920 feet wide, 1300 feet high) |
HO scale is 'half of O' scale. O (or, originally 'zero') scale tends towards a 1:48 scale, depending upon the vendor, where 1/4 inch on the model equals 1 foot in real life. HO scale models are therefore around half the size of O scale models.
The title text further expands the joke, saying as the model rail is so large he had to build a regular sized train within it to get to far portions of the project.
Model rail and its size constraints have been covered previously in 878: Model Rail.
Furthermore "OH Scale" could be a word play on Big O notation, which is a mathematical short hand that describes orders of magnitude. That has been featured previously in 399: Travelling Salesman Problem and 2939: Complexity Analysis.
Transcript
- [A two-story house is sitting in a a plain surrounded by several assorted trees, the highest of which rise to double its height. To the right of the house, taking up most of the panel, is a large metal bar (a rail), resting on two giant railroad ties (seen end-on) to which it is anchored with track clips; the bar is about eight stories tall, and the clips are comparable in size to the house. A scaffolding tower leads to the top of the bar. Atop the bar is a huge, incomplete wheel, with the left half and the bottom quarter of the right completed. The wheel is approximately fourteen stories tall and has scaffolding going up both its sides (presumably to hold it in place) and up the incomplete portion.]
- [Caption below the panel]: Due to a typo in the plans, I've been building a 87:1 model train set in my yard.
This Week's Explanation for Improvement
As part of the Explanation Improvement Project, each week the community selects one older, neglected, or otherwise stagnant explanation to expand and polish together. This week's pick is comic 395: Morning; help us by editing its explanation!
To get involved with the project, you can also nominate an explanation that you think should be improved, or vote on current nominations!
| Morning |
 Title text: I'd press on them to try to unstick them, but I can't reach. Can we try cycling day and night really fast? |
Explanation
|
Welcome to This Week's Explanation for Improvement! Anyone is encouraged to help explain comic 395: Morning; click here to get started! If you are new to wiki editing, you can read our editing FAQ for guidance. Here are some suggestions for improving this explanation: .svg){kind=icon} Explain the references to The Matrix to someone who has never heard of the movie.
.svg){kind=icon} Upload a close-up of the three colored pixels? They may be difficult for some viewers to see in the strip.
.svg){kind=icon} Explain the "screen resolution of the world" in first panel. Is there truth to this? What resolution do our eyes actually have?
.svg){kind=icon} Explain the title text, especially "cycling day and night really fast".
.svg){kind=icon} The explanation of LCD screens is too technical.
.svg){kind=icon} Mention that OLED screens are much more popular nowadays. Do they also suffer from dead pixels?
.svg){kind=icon} Could the dead pixels that Megan sees actually be simple stars visible during the day?
|
In the last panel of the comic, there are two red and one green pixel that look exactly like actual dead pixels.
Regarding the question in the first panel, "What resolution is life?" (by which "life" presumably means the "real world" or lived experience, not living biochemistry), the typical response involves Planck distance and Planck time, the smallest digital units of distance and time that time-space can be broken down into. Humans, of course, cannot perceive on that scale, but it is the fundamental building block of the time-space around us, similar to pixels (picture elements) on a screen or a bit (one-or-zero) of data. Datum. Data. Our experience occurs at a much higher level, so a lower order of resolution.
The title text refers to usual techniques for fixing a dead pixel. One way is to apply pressure and release it, which isn't possible for Megan due to the distance of the sky. Another way is to make the area of the screen that the dead pixel is on change colors really quickly, which could happen if the day-night cycle was fast enough.
Transcript
- [Megan is standing to one side.]
- We've all seen The Matrix
- We've all joked about "What resolution is life?"
- But it doesn't blunt the shock
- Of waking up one morning
- [Megan looks up from field and sees several colored pixels in the sky.]
- And seeing dead pixels in the sky.
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