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Scanning some trains


dllu

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I've obtained a specialized line scan camera and have been trying to scan some Japanese trains using strip photography.

 

The platform of the Himeji station is ideal for scanning some trains of the Sanyo Shinkansen as they blast through the station at 300 km/h.

 

Here's an example of the N700A Shinkansen set G13:

 

n700.jpg

 

With a close-up of car 01:

 

n700_head.jpg

 

The camera is stationary and captures single columns of pixels at a rate of around 40 kHz. The 404.7 m long N700 series moving at 300 km/h is scanned as an image around 200,000 pixels wide.

 

Just for fun, I also captured what appears to be a Nankai 7000 series:

 

nankai.jpg

 

This one was taken from a moving train, so you can see the background changes, unlike the Shinkansen picture above.

 

Does anyone know of any areas in Tokyo where I can scan similar pictures of other types of trains? I'd like to go around documenting the other Shinkansen trains as well, and I'll be in Tokyo for about 3 days.

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Wow, amazing picture! What about capturing some Tohoku shinkansen trains? What kind of station or place are you looking for?

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Wow, amazing picture! What about capturing some Tohoku shinkansen trains? What kind of station or place are you looking for?

Thanks! Capturing Tohoku Shinkansen trains sounds good. It seems like I'd have to find a spot somewhere between Tokyo station and Ueno station. The main requirement is that it has to be on stable ground within 30 meters of the train, and be able to view the entire height of the train from the rail to the pantograph. The vantage point should be level with the trains, or higher. An overpass overlooking the tracks that allows me to scan trains directly from above may be interesting too.

 

The last time I tried scouting out places, I walked north along the Shinkansen tracks from Tokyo station. Since the tracks are elevated, I was looking for a stairwell, balcony, bridge, or rooftop that is at the same height as the trains. Unfortunately, most stairwells have signs saying that only residents are allowed (one even said explicitly that photographers will be reported to the police) and most sections of track are covered from view.

 

Also, my JR rail pass will have expired by then so I can't get access to the station platforms. Moreover, station platforms in Tokyo tend to be full of people and unsuitable for setting up tripods anyway.

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Sounds to me like Akihabara might be suitable. Just north of the train station on the west side there is a public raised walkway where you can see shinkansens. But I am not sure if there is a wall or fence (partially) in the way, I don't remember it anymore...

Edited by Yavianice
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Akihabara

That's a good idea, I'll go check it out, thanks! I also found that there may be a pedestrian crossing over the Tohoku main line at 35.749682, 139.741416.

 

Nice! What line scan camera do you use? I've made some tests with a camcorder (like this guy http://trainsideview.ddo.jp/t/ ), but I guess a line scan camera would be a more elegant solution.

I use an industrial line scan camera called the Alkeria Necta N4K2-7C. It costs around 1900 Euros (USD $2200). I think the line scan camera produces cooler striped backgrounds and can be much higher resolution (up to 4096 pixels tall), but the camcorder is a much cheaper solution and produces really good results judging from your photo and trainsideview. It seems very tedious though. My photo took little or no manual processing.

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Wow, amazing photos! If you manage to get a shot of a keihin tohoku line e233, I'd love to get a print to hang on the wall. Thanks for sharing, I've never heard of this photography before.

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Dllu,

 

Welcome! Great images! Thanks for posting, really a fun technique that gives a view you really can't get any other way! When I first saw line scan photos I thought of looking around at our local print shops to find one with an inkjet with roll paper to print one out to the whole wall length, but framing it was a head scratcher! Now thinking a poster might be fun with a lot of trains stacked small might be really fun.

 

They really are cool images!

 

Cheers

 

Jeff

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These line scan cameras are essentially the same techology that is used for finish line photos. They depend on the train having the same speed across the whole photo, otherwise heavy postprocessing is needed. If the speed is constant, the postprocessing only needs to correct the aspect to 1:1.

 

Camcorder or photo mosaics are essentially mosaics of still pictures that are prone to line scan jitter on cheap sensors and pheripherical disortion if the train is too close to the lens. The good side is that the mosaic process works even if the train stops during the scan. Some mobile phones have this feature built in for panoramic images and if not using g sensors for turn detection might work with stationary camera and moving train.

 

Imho an app for mosaic scanning would be great.

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3 hours ago, kvp said:

They depend on the train having the same speed across the whole photo, otherwise heavy postprocessing is needed. If the speed is constant, the postprocessing only needs to correct the aspect to 1:1.

You're right. In my photos I just scaled it to approximately 1:1 aspect ratio. Fortunately, the speed of an N700 series Shinkansen didn't change much during the 5 seconds it took to move past the camera. There are techniques to automatically de-skew an image caused by trains moving at a non-uniform speed, but so far I haven't had to do that. Another photographer, Adam Magyar, also did some line scan photography of trains and discussed this issue in a TED talk.

One advantage of line scan cameras is that they are capable of very fast shutter speed. I used an exposure time of 15 microseconds (1/66667 seconds). For a train moving at 300 km/h (83 m/s), you'd need such a fast shutter speed. A typical camcorder with an exposure time of, say, 1/1000 seconds, will suffer a motion blur on the order of 8 cm. Another issue is that each chunk of the mosaic will have slight perspective distortion if the subject isn't perfectly planar, unless using a very long (telephoto) lens, or an image-space telecentric lens.

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I'm in Kagoshima enjoying some hot springs. Meanwhile, I found an old KiHa 47 diesel multiple unit on the Ibutama line.

ibutama_kiha47.jpg

The train is actually black on the right and white on the left but I only scanned one side of it (the white side). The train was accelerating much slower than expected so even a 30 second capture wasn't enough to get all 4 cars.

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Huh, I didn't know the Ibusuki no Tamatebako was 4 cars? I have only seen it/been in it as a 2 car train myself. 

Where else do you plan to go? Kyushu has very many good looking (and some less good looking) tourist trains. Will you publish a photo album of your pictures? I would be very interested to see it!

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21 hours ago, Yavianice said:

I am referring to this walkway:

https://goo.gl/maps/BH6tzuRUJF32

Apparently, this walkway is no good as the platforms inhibit the view slightly and the Shinkansens are entering the tunnel to go to Ueno.

This bridge, just north of Nishi-Nippori station (on the Chiyoda line) might be suitable? There is a chainlink fence, but it seems that you have a clear view of the Shinkansen branch to the servicing area. Unfortunately the main line seems to be walled off, so you have to be lucky when a Shinkansen enters the servicing area.

https://www.google.de/maps/@35.7350708,139.7659009,3a,75y,261.94h,70.8t/data=!3m6!1e1!3m4!1szr_PC-7IlraHwGwiIk-QFg!2e0!7i13312!8i6656?hl=en

The bridge you linked also seems to be inhibited by a concrete wall to the Shinkansen line by the way.

Edited by Yavianice
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15 hours ago, Yavianice said:

Huh, I didn't know the Ibusuki no Tamatebako was 4 cars? I have only seen it/been in it as a 2 car train myself. 

Where else do you plan to go? Kyushu has very many good looking (and some less good looking) tourist trains. Will you publish a photo album of your pictures? I would be very interested to see it!

Three cars as explained earliers. Since 2015 I thnk.  The third car is a kiha 40 with big double windows like the Hayato no Kaze and Isaburo-Shinpei.

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On 21/08/2017 at 11:20 PM, Yavianice said:

I am referring to this walkway:

https://goo.gl/maps/BH6tzuRUJF32

 

That will give an excellent view of the northbound Keihin-Tohoku line, but the Shinkansen line is on the other side of the station on a descending line.
This photo was taken from the walkway:

34459371682_4337fd5aa1_z.jpg
low-bridge-akihabara-station by Rail Squid, on Flickr


There's a MacDonalds on the other side which has (IIRC) a decent-ish view of the Shinkansen line.

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On 21/08/2017 at 11:07 PM, dllu said:

Thanks! Capturing Tohoku Shinkansen trains sounds good. It seems like I'd have to find a spot somewhere between Tokyo station and Ueno station. The main requirement is that it has to be on stable ground within 30 meters of the train, and be able to view the entire height of the train from the rail to the pantograph. The vantage point should be level with the trains, or higher. An overpass overlooking the tracks that allows me to scan trains directly from above may be interesting too.

 

The last time I tried scouting out places, I walked north along the Shinkansen tracks from Tokyo station. Since the tracks are elevated, I was looking for a stairwell, balcony, bridge, or rooftop that is at the same height as the trains. Unfortunately, most stairwells have signs saying that only residents are allowed (one even said explicitly that photographers will be reported to the police) and most sections of track are covered from view.

 

Also, my JR rail pass will have expired by then so I can't get access to the station platforms. Moreover, station platforms in Tokyo tend to be full of people and unsuitable for setting up tripods anyway.

You can get platform tickets, though tripods are very probably not allowed anyway.

North of Ueno, there may be a number of locations like this: https://goo.gl/maps/cPsBNNnohk32 where the land to the left (west) of the railway lines is elevated, putting you more-or-less level with the Shinkansen viaduct.

Roof of the JR museum in Omiya might be an option. Good side views from the Saikyo line platforms north of Akabane too.

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