Saturday, February 16, 2019

Visiting London's Underground Farm

More adventures underground, this time visiting the Growing Underground farm in a WW2 bomb shelter in south London.

I'd been down the Clapham shelters before for an art installation (natch) and was told tunnels nearby were being used for a farm. That intrigued me so when tickets appeared for a visit I snapped up one quickly.

The aim is to produce low emission high quality food within urban areas. The idea came from the vertical farm but the initial concept in that book has difficulties, not the least cost, but also temperature control.

Using empty tunnels is not just cheaper, it is actually beneficial to keep the plants to the required temperature, particularly if horizontal (like here), rather than a shaft, as there is less height differences and hence less temperature difference.

In the racks shown above, salad is being grown, and the colour isn't wrong, that's what it looks like: the LED lamps only emit the frequencies used by plants i.e. excluding green.

The seeds germinate in one hot and humid tunnel (below) that still looks like the air raid shelter it is, before being transferred to the growing tunnels such as the one above.

The seeds are "planted" on what looks like carpet with the roots below picking up nutrients directly using hydroponic techniques:

We got to try some of the crop and wow! was it tasty! Intense flavours - my favourite were the pea tips.

It was all very high tech, indeed these types of farms are being studied by NASA for future space colonies.

But its also potentially very useful here on Earth. The two biggest environmental problems with have are global warming and loss of habitat, and farming contributes to both of these. Putting the farm underground means land can be returned to wildlife (surely better) and the LEDs can be timed to come on when there is spare renewable energy (e.g. wind farms at night).

And there are lots of potential sites for expansion, from cold war bunkers to coal mines. According to this BBC article, in the UK there are 25,000 km^2 of disused mines and tunnels. And with the potential to have up to 60 crops per year, that could be very productive.

Plus, have I mentioned it was delicious? Already its products are being used in restaurants, and one of their advisers is none other than Michel Roux Jr.

Absolutely fascinating, another of the wonders beneath the streets of London.

Wednesday, February 13, 2019

Photography Blog: Do you need Full Frame?

The Bursledon Blog had a post about cameras and how much the tech is required which interested me as it's a topic I've been thinking about. In particular, the long debated question "do you need full frame?".

This question relates to sensor size which relates to how big a camera is and a whole host of other factors. Basically, the order is:

  • Full frame 36 x 24mm 
  • APSC 24 x 16mm e.g. my Sony A6xxx series, shown above
  • 4/3rds 17 x 13 mm
  • 1 inch 13 x 9 mm e.g. my Sony RX100m4
  • 1/2.3 inch e.g. my GoPro 5 Black, Mavic Pro drone
  • 1/2.6 inch 5.5mm x 4.1mm e.g. my Pixel 2 phone

There is a school of thought that to be a true photographer you have to use full frame and only noobs and amateurs use anything else. But is that right?

As always, the answer it that it depends, most importantly, on what sort of photography you do, and is strongly connected to the choice of lens.

Many years ago I did a camera comparison and Tillerman commented all the photos looked very similar, which is a good point. For scenes such as these, well lit, using medium aperture and results displayed on small sizes on a screen, there is very little difference and so you don't need full frame.

However there are times when this is not true, such as:

  • if you want shallow depth of field and use lenses with large aperture, then full frame is better (e.g. for portraits)
  • if you want to take photos and videos in low light, then larger sensor (again, with suitable lens) is better

But how often is that the case for you? With me its not that often, as I get sufficiently shallow depth of field for portraits with my APSC camera if use longer focal length and/or shoot wide open. Also, these tend to be family photos, so the moment and expression are most important, not technical details.

That's an important point: very often its composition that is key, not technical details for pixel peepers. On one of my Greenland trips, someone was just taking photos on his phone and they were great - but he was a film director, used to thinking about composition and using what he had.

The APSC camera is usually, but not always, ok with low light scenes. Sometimes you can get away using a tripod, other times there is actually enough light (e.g. London at night isn't that dark). But there are shots my A6500 can't handle - such as I tried to take a video of us sailing off Morocco under moonlight, and the noise & lack of dynamic range were disappointing.

However that's rare, and there's another consideration, which is weight and size. I take pictures for fun, often while travelling, and there is a significant difference in weight between full frame and APSC. On another Greenland trip I was there with my A6300 and someone else had the full frame Canon 5Dm3. In a battle on features the A6300 would win on all counts apart from sensor size and yet was literally half the size and weight, which to me is an important factor.

And if you're going to crop, e.g. for wildlife photography, you might as well go APSC to start with.

If you're a professional photographer then maybe you'd take what is required because its a job, but I was off travelling for fun, and that fun is a lot less if you're carrying many kilos of weight you don't need most of the time.

There's a saying that the best camera is the one you have with you: yes, the APSC camera might struggle with some shots but if the full frame is so large you leave it at home, you might actually get more shots using a smaller sensor camera as you'd actually bring it.

Then there are specialised niches, such as action cameras. Yes, you could strap a full frame camera to you head and take videos of you zooming down mountains, but its much more sensible to use a GoPro even if its sensor is smaller.

Similarly you might want a stabilised camera, using (say) a gimbal. These are what professionals use to get the butter smooth flowing shots, but that all adds weight. Say you have a full frame camera, good lens & gimbal - that might be 2 - 3 kg in total. Plus you'd need other stuff like ND filters, batteries, external mics, recorders etc etc. Yes the results might look great, but I'd never travel with it.

Instead what I've recently got is the DJI Osmo Pocket, small enough to take anywhere and weighing only 118 grams. Ok, the image isn't brilliant but what matters is story telling and the best camera is the one you have on you, and you can take this anywhere.

So there's not simple answer: it depends on what sort of photography you do.

Maybe one day I'll go full frame, but don't feel you have to. Focus on composition and think about what lenses you need.

Sunday, February 10, 2019

Cadiz and Three Kings

I'd visited to Cadiz before when sailing from Lisbon to Gibraltar, and it was great to explore this beautiful city again. Previously (as blogged here) we'd moored at nearly the same berth in the marina as before, as can be seen in these two photos:

Oriole, 2019:

Selene, 2006:

Golly, time does fly by, doesn't it? So there were all sorts of memories when walked from the marina into Cadiz, as in the top photo.

The previous time was during the visit of the Tall Ships, which was very lucky. This time was lucky again, as was there for the Three Kings celebrations:

This is the big event in Spain, more significant than Christmas day. There were a series of processions on different days in which men dressed as kings throw handfuls of sweets at kids in the crowd.

Then we went for dinner had lovely fresh fish:

Thursday, February 07, 2019

Sailing Europe to Africa: Seville, Cadiz and a green ray sunset

I was to join the yacht in Cadiz, but there isn't an airport there, so you have to fly to one of the nearby cities and then takes a train.

I flew to Seville (seeing a great sunset on the way, above) as I'd been there before and really liked it:

There was time for some tapas, a stroll around the town (complete with ice cream), listen to a little guitar music then head for the hotel.

The next day took the train to Cadiz where saw yet another rather nice sunset:

There was even a green ray!

Monday, February 04, 2019

A partial sail trip from Europe to Africa

Last month I was meant to sail from Cadiz down the coast of Morocco then across to Lanzarote, as in this route map:

Alas the lurgy that I've had several times before came back so I had to leave the yacht at Rabat, but at least I managed to sail from Europe to Africa.

It was a trip by Rubicon3 down the coast of Morocco in yacht Oriole (top photo, in Cadiz).

Ah well, at least I can post on the first part of the trip.