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MUNI Heritage Weekend in San Francisco

204 pointsposted 6 days ago

(daniel.lawrence.lu)

56 Comments

dllu

5 days ago

OP here, ask me anything! I've also written about the process previously:

- Line scan camera image processing: https://daniel.lawrence.lu/blog/2025-09-21-line-scan-camera-... Previous discussions:

  - https://news.ycombinator.com/item?id=44996938

  - https://news.ycombinator.com/item?id=46383593

  - https://news.ycombinator.com/item?id=46388084

- Standalone line scan camera hardware: https://daniel.lawrence.lu/blog/2026-06-12-standalone-cnc-li...

- Line scan camera image processing 2: https://daniel.lawrence.lu/blog/2026-08-02-line-scan-camera-...

big_toast

4 days ago

Your other photos are always very pleasant to look at too. Thank you for sharing them.

Are there other photo types you've thought about taking? (I don't know very much about the topic. Rocket launches? Cruise ships? 360/Cylindrical line scan sweeps?)

I assume the train rails and constant motion are part of the appeal of making trains the subject. I can't exactly think of parallels, maybe a factory assembly line.

dllu

4 days ago

I took one of my baby on the swing. It needed custom polar coordinate dewarping:

https://i.dllu.net/swing_07_7668f7f16ff7ac2a.png

Also motorcycle cops:

https://commons.wikimedia.org/wiki/File:San_Francisco_Police...

I never thought about it until seeing these, but line scans yield an orthographic projection in the scan direction. There was a little bit of uncanny valley being able to see parts of the front/back of the car that would have normally been compressed out occluded by perspective.

ramses0

4 days ago

Yarp... Mr. Lu, please go to your nearest gigantic poster shop and immediately start selling these prints at art-gallery prices! There's a brief moment in time where you've a monopoly on "pictures that look like this" and you'd probably be able to make your money back (and more) on this highly distinctive photograph style. Do some back and forth chat with AI on "fine art photography pricing structure" and "signature style / visual voice" and you'll likely be pleasantly surprised.

...and I'll be surprised if I don't see these pictures hanging in a bank/startup lobby at some point!

dllu

4 days ago

Also, I don't have a monopoly on "pictures that look like this".

Adam Magyar and Jay Mark Johnson have line scan photos in fine arts as well, and they were in fact a big source of inspiration when I started out on my own line scan journey in 2017.

- https://www.magyaradam.com/wp/?page_id=368

- https://www.jaymarkjohnson.com/works

Seth Itow, Philomena, and Elm-chan both also have hobbyist line scan camera setups:

- https://www.sethitow.com/posts/2026-linescan/

- https://philo.gay/linecam/

- https://elm-chan.org/works/lcam/report.html (be sure to scroll down and click on the train pics)

There are also Japanese rail fans:

- https://kr64.seesaa.net/ with a bewilderingly huge collection of trains all over Japan,

And faux-line scan cameras using regular video cameras, stitching together thin chunks rather than 1 px columns:

- https://railfile.jp/

- https://x.com/yamakox/status/2089934720759144653

- https://kakeyama.image.coocan.jp/index.htm

- https://trains.jo-m.ch/#/trains/list

Line scan cameras are also commonly used for machine vision in the rail industry to inspect trains for damage and detect graffiti and stuff. And conversely, line scan cameras mounted on trains are used to inspect rails and tunnels.

ramses0

4 days ago

Nuanced and humble responses... I'm happy for you and all the retro-futurist techies that'll end up with your photos on their walls!

My responses came from a place of emotion, because there's something about them that is so striking, the odd perspective (or lack), the solid "non-blur" of a background, the juxtaposition of subject and method... when you stack all that together it's something special, and "selling" (or more precisely: letting people buy/vote with their money) is one way to encourage more of what you're doing.

Seriously, do your one of three artists proofs for some of these and shop around a gallery showing with SFAC or SF City Hall, then sell your "works exhibited to the public with certificate of authenticity and 10% of sale price going to SF muni"

They're just too striking not to get more eyes on them! Even if you don't, hopefully you feel the little warm glow of having climbed this mountain!

dllu

4 days ago

I just set up a shop at https://shop.lawrence.lu/. I also emailed Rick Laubscher and Alison Cant at streetcar.org [1] yesterday but they haven't gotten back to me yet.

[1] https://www.streetcar.org/about-sfmsr/

dole

4 days ago

Hell, I'd shop them around to transit authorities. Gorgeous photos, awesome hardware and processing techniques that went into them.

Animats

4 days ago

Of course. The first outlet to try is Muni's streetcar museum, which is at the turnaround loop at Market and Embarcadero.[1]

[1] https://www.streetcar.org/museum/

ramses0

4 days ago

Donate copies to sfmuni (no matter what!), or front them as "distribution partner", ie: they sell those posters for $999.99 or whatever and cut checks to Mr. Lu for $99 each (or something).

thompson-rc

4 days ago

This is sick, dude! I liked the formatting of the website, quality of photos, and minimization of extra fluff.

Theodores

4 days ago

I have a long-standing dream to use a line scan camera from a moving train, assuming everything would be easy, if I had the camera. Little did I realise how much work is needed to tidy up the imagery!

Your work is extremely beautiful, and I am truly envious of your work, the aesthetic is awesome. I want to do it on the cheap though, with a regular phone as camera.

I think you have given me the directions needed to make some bold steps towards getting what I want out of the 'medium'.

dllu

4 days ago

If you want to use a regular phone or camera, check out TrainScanner!

https://github.com/vitroid/TrainScanner

It converts a regular video into a line scan style photo. It works by stitching together small chunks rather than 1px thin slices, so the background has a repetitive texture rather than being smooth horizontal stripes. But at lower resolutions, it looks similar, especially if you pick a spot with a clean background. Also the trains turn out very detailed.

Example work by Kakeyama from Japan using this: https://kakeyama.fan.coocan.jp/tec/e5e8r.htm

Theodores

2 days ago

Many thanks! Those trains are beauties. Looks like I had best get out there, giving it a go. It is canalside that I want.

maddie0

4 days ago

Have you seen https://philo.gay/linecam/ and https://github.com/FlamingSpork/grindstone for the postprocessing code?

(previously on HN frontpage, and before that, at EMF Camp!)

dllu

4 days ago

I actually reached out to Philo on GitHub Issues but she hasn't responded yet [1]. I also mentioned her cool camera on my blog [2].

By the way, I recognize your username as the person that Philo credits with "rewriting grindstone in idiomatic NumPy". That's super cool!

[1] https://github.com/FlamingSpork/grindstone/issues/1

[2] https://daniel.lawrence.lu/blog/2026-06-12-standalone-cnc-li...

Theodores

2 days ago

Looks like a realm of 'I bit off more than I can chew' when it comes to results. Good to see OpenSeadragon in the wild on Flaming Spork's site (for prsenting images). It is a rarely ploughed furrow of artistic endeavour, and I suspect that is for good reason (of difficulty).

My plan was to experiment on the canal towpath with bicycle and basic android phone. I think I need a proper camera and the train.

trebligdivad

4 days ago

They're great - I'm pleasantly surprised there's no blur on the people.

dllu

4 days ago

If people are moving, they may get stretched or distorted. But they won't ever get blurry, since the capture rate is like 10,000 lines per second.

wxw

4 days ago

These are fantastic, thanks for sharing

plun9

5 days ago

oh ok

matja

4 days ago

I like the photos, they look like architectural diagrams.

I suppose the subjects moved past the camera perpendicular to the lens direction, so you only see one side.

Are there any examples of what it looks like with a line scan camera when a subject goes past at an angle?

Also, for anyone setting up a tripod with a tripping hazard in public, do consider public liability insurance :)

abeppu

4 days ago

Ok the photos are cool and it's nice to see the vintage street cars. But Muni has a budget shortfall and is planning on cutting a bunch of bus lines and reducing frequency on lines across the system. Meanwhile, it has an internal supply chain to custom build replacement parts for vintage vehicles that no other city will operate, and teams of specialist restorers. Viewed in isolation, they look cool! Viewed in context, is this ... irresponsible?

kelnos

4 days ago

From what I understand, the grants to restore the old railcars don't come from their general funds (and if they decided not to do them, they wouldn't get the money). But I'm sure a lot of the regular maintenance comes out of their regular budget, and I agree that's a difficult thing to justify.

I wish they could do something about fare evasion. I ride Muni fairly often (both buses and trains), and I see maybe 20% of people paying when they get on. I know some of the remaining 80% probably have monthly passes or something and don't strictly need to tag on, but I can't imagine it's a large percentage. Biggest offenders seem to be out-of-towners who are going to Chase Center or Oracle Park events (I live in the Dogpatch and see a lot of that on event days). There's no excuse now that the fare terminals accept NFC credit cards too (and not just Clipper cards). I expect getting more people to pay could solve some of these funding problems, or at least make them less severe.

(I do wonder if the cost of fare enforcement exceeds what they'd recover in fares, though...)

wolfgang42

4 days ago

I couldn’t find any documents on percentage of riders by payment method, but [1] says that in 2025 they actually got $14M more in fares than they budgeted for, partially because of “increased ridership that is paying full — or close to full — fares.”

Looking at the list of options on [2], your observed 1-in-5 Clipper taps seems within the realm of plausibility; there are a lot of ways to pay for Muni that aren’t visible to fellow passengers. In particular, out-of-towners who plan to ride Muni a lot are likely to get a MuniMobile (or, for the old-fashioned, paper) pass; and a ticket to any Chase Center event also counts as a Muni day pass. You also mentioned monthly passes (I know a lot of people who get them from their company’s commuter benefits), and there’s also transfers: not only are “single ride” fares valid for 2 hours, but if you board after 8:30pm you can’t tap again, because Clipper can’t handle it and you’ll be double charged!

[1] https://www.sfmta.com/projects/paying-your-fares-keeps-us-mo... [2] https://www.sfmta.com/getting-around/muni/fares

ProfessorLayton

4 days ago

>I wish they could do something about fare evasion.

Reminder that vast majority of the fare is covered by taxes (Roughly 87%). I wish they just funded the remaining 13% instead.

It might not even cost that much more considering all of the expenses involved with hiring more staff (Salary/healthcare/pensions etc.) to collect the last 13 cents on the dollar.

aesthesia

4 days ago

This doesn't feel like the right way of thinking about it---if you went from 20% of people paying fares to 80%, that's 4x the revenue with the same fixed costs, and farebox recovery goes from 13% to 52%. Now, I don't think compliance is actually that low, but the point is that you shouldn't think of fares as collecting a fixed share of the operating costs.

ProfessorLayton

4 days ago

The costs may be fixed but so is ~87% of the revenue via tax money.

Muni can be 100% free without increasing taxes too. The people using public land to store their private vehicles are not paying their fair share. Proper parking pricing and enforcement could easily pay for Muni’s deficit.

aesthesia

4 days ago

Yes, money is fungible. But why should it be that people who park cars on the street need to pay their fair share but people who ride Muni don't need to pay anything?

fragmede

4 days ago

To incentivize the people taking their cars to use the bus instead!

aesthesia

3 days ago

Sure, but then it's not about a "fair share" any more; it's about incentivizing specific behaviors.

ProfessorLayton

3 days ago

It's both. Why should the public 100% subsidize private vehicle storage in vast swaths of the city (And greatly undercharge when it's paid), but not public transit?

SF has some of the most valuable private[1] and public land in the US. Why is it so pressing to charge the last 13¢ on the dollar for a Muni rider, but not for drivers to pay for the public space they're storing their property on?

[1] Private land owners know this, which is why they charge a lot to use their parking garages/parking lots in SF.

aesthesia

3 days ago

The proposal was to charge for public street parking so we can make Muni free. That's not (at least not obviously) a "fair" allocation, it's just a transfer from one group to another. I agree that it's bad for street parking to be free, I just don't think it's necessarily the best use of funds from that to make transit free. If you're spending on transit, why not spend the money on expanding service instead?

ProfessorLayton

3 days ago

> The proposal was to charge for public street parking so we can make Muni free.

My proposal is to make Muni free full stop. Via taxes is fine with me, I provided another way that doesn't necessitate that. We are already paying for the vast majority of each Muni trip from taxes.

>That's not (at least not obviously) a "fair" allocation, it's just a transfer from one group to another.

You're saying we're just transferring from one group to another, well SF was built for people before cars became commonplace, with excellent public transit before it was torn out for cars. I'm arguing that some of that needs to be transferred back to the people for better use (Bigger sidewalks, bike lanes, restaurant parklets etc.)

>If you're spending on transit, why not spend the money on expanding service instead?

Expanding service is great, but you'd be hard pressed to pay for it via parking meters/tickets and it costs even more to run a system on top of that, particularly the metro system.

convolvatron

4 days ago

looks like the one time cost for doing a renovation is around $1m per car, and are funded by spot grants rather than the general budget. I was unable to find the overhead involved in ongoing maintenance, but it looks like killing the F line is already on the table.

abeppu

4 days ago

Apparently the cable cars have by far the highest cost to operate per hour anyway.

At 2024 numbers in this SPUR report:

Cable car 872 streetcare 631 lightrail 412 system avg 327 motorbus 302 trolleybus 281

So canceling each cable car could IIUC, allow the system to add roughly 3 electric buses.

https://www.spur.org/sites/default/files/2026-03/SPUR_Taking...

wolfgang42

4 days ago

Note that Muni cannot legally reduce cable car service; the city charter[1] mandates a minimum level of service, due to a 1947 ballot proposition[2]. As your link notes:

> Cable cars are a symbol of San Francisco, a major tourist attraction, and an indelible feature of the city’s cultural and historical landscape. [...] While SPUR doesn’t recommend changing SFMTA’s role in cable car operations, the agency may wish to explore options to generate additional revenue from the cable car system or seek supplemental support from the city’s budget, given the outsized expense of providing cable car service and the unique value this mode brings to the city as a cultural attraction. SFMTA already acknowledges the special status of cable cars by pricing them differently from other modes and by excluding cable car service from some of its passes and fare discount programs.

Apart from that, I suspect the per-service-hour figure is particularly misleading for cable cars and removing one cable car from the schedule would free up significantly less than $871: there is a significant fixed overhead (from power usage and cable wear) to having the system running at all, regardless of how many cars are on it.

1: https://codelibrary.amlegal.com/codes/san_francisco/latest/s... 2: https://www.cablecarmuseum.org/60th_Anniversay.html

Animats

4 days ago

> there is a significant fixed overhead (from power usage and cable wear) to having the system running at all, regardless of how many cars are on it.

Each cable car trip costs Muni about US$20. They charge about $8.

I was amazed when I first found out how the grip worked. I figured they clamped pulleys around the cables and then applied brakes to the pulley system. Nah. It's brutally simple. They squeeze two soft metal plates around the cable. The cable wears a groove in the plates during starting and stopping. Those plates are replaced every 3-4 days. The cables are replaced every few months.

Plus the thousand or so pulleys under the street need regular attention. The whole system has way too many friction points, which means intensive maintenance.

The PCC streetcars were a really good design, built for efficient operation with modest maintenance. Their successor in San Francisco was built by Boeing Vertol, which totally botched it.[1] None of those cars are still around. The PCC cars roll on.

[1] https://en.wikipedia.org/wiki/US_Standard_Light_Rail_Vehicle

abeppu

4 days ago

How about the reducing the F, which for a decent portion of its route down Market is directly above the underground KLM lines? The F is slower and lower capacity per car and stops at lights (and stops traffic when it needs to turn) in addition to apparently being more costly to run. I am clearly not a transit planner or traffic engineer, but it seems perfectly reasonable to run the F only from the Ferry Building to Fishermen's Wharf.

- People who want to go up market can transfer to the KLM at Embarcadero and if they're going to Castro (or maybe Church?) they may also get there faster.

- If tourists want to see an old-timey street car, they could ride one perhaps half the distance, only along the water with views Coit tower, and the eastern end of the line would be right by the Railway Museum anyway. And we could run perhaps half as many cars.

SllX

4 days ago

The part that runs on Market Street is the useful part. The part that runs along the Embarcadero isn’t useless, but it’s more seasonally useful. I’d rather see the old PCC cars replaced with a solid modern low-floor LRV using more standardized parts & aggressive transit policing to keep freeloaders from abusing the system. It is partially redundant with the subway, but if you’re going to have a surface street railway anyway, I’d rather it be optimized for local use.

You could pull the J up from underground too using the same low-floor LRV model chosen for the new F, having it turn at Church & Market rather than making an awkward diversion to Church & Duboce first.

dam_jackalopes

4 days ago

Depends on what value you place on the vehicles I suppose.

kqgnkqgn

4 days ago

The photos are really cool, and I do like trains and infrastructure in general.

But came here to say the same thing. There is an advertising campaign in SF right now to encourage people to vote to give Muni more money (again) in November, because they can't cover their essential costs. This...looks pretty non-essential to their core mission to me.

They should have done everything they can inside their org to cut costs, before going to ask residents to give them more money.

Now I hope - maybe this is primarily funded by donations / grants or volunteer work, and SFMTA contributes very little to this. If so great - but it would have been wise for them be very clear about that.

tobiasdorge

4 days ago

I'm a member of Market Street Railway (https://www.streetcar.org/) which does a lot of advocacy to keep these street cars maintained. Many of these cars were either purchased long ago from other cities that would have otherwise scrapped them (most of the PCCs, the long sleek ones) and others are often either preserved Muni originals or donated / purchased by Market Street Railway. Car 162 just came back into service and was purchased by Market Street Railway and worked on by volunteers (and Muni) [1]

I obviously am I biased, and think this is very very cool. There are many intangibles here beyond the budget numbers; a bit of history, a bit of whimsy, a bit of color to what is often utilitarian (public transit). It certainly attracts tourists to the city (I was pretty surprised at the number of out of towners at Muni heritage weekend).

But I do think it's important, not just for tourism but also as a legitimate connector along the Embarcadero corridor that otherwise has no public transit along it. Agree that a breakout of the cost of maintaining these things would be appreciated, not sure if that exists in clear terms, but I don't think it's massive. For example Car 162 was damaged in a collision in 2014, and took 12 years to fix and return to service. For many gripmen / Muni restorationists working for the city, it's a side project.

And while I'm here, I'd be remiss if I didn't post an article about Maurice Klebolt, one of the biggest advocates for vintage transit in San Francisco. It describes how he acquired car 106 from the Soviet Union [2]

[1]: https://www.streetcar.org/streetcars/162-162-muni-1950s-live...

[2]: https://www.streetcar.org/remembering_a_trolley_titan/

dang

4 days ago

Re https://www.streetcar.org/remembering_a_trolley_titan/: that would make a great HN submission in its own right! We should just let enough time go by so it doesn't count as a follow-up [1].

Would you be up for posting it in, say, a couple months and then email hn@ycombinator.com? We'll put it in the SCP [2] for sure, so it will get a random placement on HN's front page.

[1] https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...

[2] https://news.ycombinator.com/item?id=26998308

tobiasdorge

4 days ago

Sure; can do!

Goatsgiats

5 days ago

These are really lovely.

gerikson

4 days ago

Very cool images!

What lens are you using? Does it have to cover 135 format?

dllu

4 days ago

Muni heritage weekend was shot on my new Voigtlander Apo Ultron 90mm f/2. The line scan camera's sensor is 28mm long so any APS-C lens will work, not necessarily full frame. I modded my line scan camera from Nikon F mount originally to Sony E mount so that I can use more compact high quality lenses like M mount ones.

Previously I've also used these full frame lenses:

- Myutron 50mm f/2.6 (Shinkansen N700A, SF Cable Car 2017)

- Voigtlander Nokton 58mm f/1.4 (Brisbane Queensland EMU)

- Samyang 135mm f/2 (Madrid AVE Class 102 and Shanghai maglev)

- Voigtlander Apo Lanthar 125mm f2.5 (Yamanote Line, CR400AF)

- Voigtlander Apo Skopar 90mm f/2.8 (London Tube photos)

- Voigtlander Ultron 35mm f/1.7 (Hong Kong trams)

and APS-C lenses:

- Cheecar 50mm f/1.2 (Osaka trains)

- Samyang 85mm f/1.8 CS (Caltrain)