Don Coffey cab ride video discussion

[Don Coffey]

The big rolling bascule bridge over the river hasn’t opened since 1956, I understand it’s no longer functional. Which isn’t intended to criticise your description of how it would have worked back when it was working. Massive structure but only low power required..

I know but I love such incredible structures. It has carried millions of tonnes of trains and road vehicles over the years.

 

[SteveyBee131]

The Cleethorpes to Oxford Road Video will air on Thursday 22nd at 19:00 UK time. Instructor Assessor Nic Blair who drove it for us will be there to answer your questions so all being well we’ll see you on Thursday.

I'm really looking forward to this one! I enjoy all your videos, as they're very informative and enjoyable, but this is my local line so it'll be extra special

 

[Pigeon]

Just watched this - thanks again! Nice bit of new mileage, and I agree about the bridges, it's a shame we can't see them actually operating any more.

 

[Railwaysceptic]

Super stuff!

On this note I have found that it is better to download cab rides in webm format rather than mp4, when it is available (which it is at least for anything recent, including Don's). When the mp4 encoder starts to find the images too complex to encode all the detail without too much loss and still stay within the bit rate limit it's been told to keep to, it tries to save bits by encoding less detail on the parts of the image that don't move very much - which of course on a cab ride means the "vanishing point", right where you're most looking, and also means that it's losing detail in a spot which will always become successively magnified in subsequent frames as the train moves forward. This repeated magnification of the low-detail spot comes out as a succession of rings of blurriness that expand out of the vanishing point and whiz towards you at a rate of about three a second, which is most annoying.

The vp9 encoder youtube uses for webm videos, on the other hand, does its emergency-bit-saving by choosing bits of the image where there is lots of random detail close to the limit of resolution to skimp on, presumably on the basis that you're not going to see those bits too well in any case so it doesn't matter too much. On cab rides this means you start to get blurred patches in the tangliest tangles of twigs in the trees at the lineside, which is still a nuisance but is much less annoying than the "Time Tunnel" effect of the expanding rings that mp4 produces.

vp9 is also a more efficient encoder, so the webm files are roughly half the size or a bit over compared to mp4, as an extra bonus.

I've just started to re-record videos using the webm format and yes, they are noticeably better, so thank you for alerting me to that option.

 

[Don Coffey]

A new video on Monday 15th April. Filmed by our usual Freightliner driver, it follows a light engine movement from Earles to Leeds Midland Road. A freight only line and an “Z” move (I made that up) to get on the depot. Don’t miss it - 19:00 UK time

 

[Y Ddraig Coch]

Looking forward to it. What is the line speed on that one?

 

[Railwaysceptic]

A new video on Monday 15th April. Filmed by our usual Freightliner driver, it follows a light engine movement from Earles to Leeds Midland Road. A freight only line and an “Z” move (I made that up) to get on the depot. Don’t miss it - 19:00 UK timeView attachment 156244

Many thanks in advance. My favourite in-cab videos are those which show freight-only routes.

 

[Pigeon]

I am intrigued as to which freight-only route it could be. Does it go GC from Sheffield to Rotherham? I await Monday's answer with bated breath.

 

[Pigeon]

...Ah - the Crofton link - thought that was not entirely freight-only.

Great to see all the new track going in around Dore. But what is that thing with the silver tarpaulin over it just before Tesco on the down side? Just temporary or what?

Entirely agree about the degree of desolation north of Sheffield. I do remember it with all the railway land full of tracks. It's awful to see the way it is now, as is what they did to Masborough station. Pause here to wail a lament for the original Midland route from Swinton to Goose Hill, which we passed both ends of and crossed under in between... imagines additional caption on passing Goose Hill, ...this is where we should have come out if we could still go the way Stephenson intended... And it's a shame it's now too overgrown to appreciate the enormous hole they dug out between Goose Hill and Normanton to put sidings in. Tremendous expenditure of effort doing all that by hand, and it used to be most impressive, even if it did always make me wonder why they didn't just do it on the other side of the station where it's more flat.

As always, thanks Don!