Samyang 8mm for Wikipedians

There are various cheap manual 8mm fisheye lenses out there. Samyang’s offering appears to be the best of the field and has the advantage that it can be purchased in the UK without going through the Ebay store. The thing’s full name is “Samyang 8mm f/3.5 Fisheye Lens AS IF MC CSII (Detachable Hood), CANON EOS” which is probably a reflection of how many versions samyang likes to produce of its lenses rather than anything else.

In terms of build quality the lens seems solid enough and much the same applies to optical quality. I have had some slight issues with the focusing ring not always staying in place. I don’t spend time taking picture of test charts so I’ve leave the pixel peeping conclusions to those who do. The lens seems pretty sharp mind. One optical issue worth mentioning is that the lens apparently uses a stereographic projection resulting in a less extreme fisheye effect than other fisheye lenses.

So is it useful to wikipedians? To an extent. When I purchased this lens I was expecting it to be like the Samyang 800mm. More of a toy than a useful lens but the 8mm is a serious bit of optical equipment. Where as the 800mm only produced images useful for showing the optical effects of a mirror lens I could actually see some of the 8mm being used in articles. For example this image would be usable if I wanted to write an article about the Barbican conservatory.

Against that rectilinear lenses are likely to be more useful in most cases and for much the same money you can buy a Samyang 14mm. Still if you already own a 14mm lens and want something wider still the samyang provides a cheap and fairly high quality way to access the fisheye world.

All my use of the lens has been on a full frame camera which produces a slightly cropped circle as the resulting image. Looking at what’s on commons suggests that the results on ASP-C sensors should be even better although you get a slightly reduced field of view.

Final conclusion; If you have already reached the limits of rectilinear linear lenses and you can afford its fairly reasonable price its a lens worth owning.

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Musing on a Let’s Play videos and wikipedia

The wikipedia article on Let’s Play videos lacks an example. This is understandable. Wikipedia isn’t video heavy and the vast majority of games are locked down under extensive copyright.

There are some free ones though. The one I’m most familiar with is Battle of Wesnoth. A pretty solid game and a search of youtube shows that let’s play videos of it do exist. However such videos are pretty long. There isn’t much work on how long encyclopedic videos should be but I feel for that for the most part they should max out at under 10 minutes.

Probably the best bet in that case is would be racing type games. Looking at wikipedia’s list a couple of them are based off the light cycles from Tron. I’ve actually played one of the (GLtron) and while fun there are potential copyright issues here (although lets face it no one is going to sue). X-Moto looks rather like an elasto mania clone. I’m not aware of much caselaw in the area but it might be a theoretical concern. Speed Dreams looks to be the best option in terms of copyright, graphics and actually being out of alpha/beta. Copyright wise and lets play video of the thing would need to be released under the free art license.

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The Canon EF 50mm f/2.5 Compact Macro for wikipedians

This is the cheapest of canon’s macro lenses. While not up to L glass standards I have no particular complaints about its build quality or optical quality. Since I don’t spend my time taking pictures of test charts I can’t really comment on its absolute optical performance beyond saying its adequate and I hear that its slightly edges out the nifty 50 in optical quality (but then given the extra cost it probably should). One technical issue is that instead of the 1:1 magnification most macro lenses give the the 50mm Compact Macro only offers 0.5 magnification. The focus system is rather noisy and the extending barrel can be annoying in some situations. The manual focus ring looks like it should be a weak point but it seemed to stand up to a fair bit fiddling.

So how useful is the lens for wikipedians? For proper macro photography (full lighting setup and effectively a tabletop studio) its probably going to be worth spending the extra money to get a lens that allows proper 1:1 magnification. For more casual out and about use extension tubes are cheaper and lighter. Still those involve a lot of lens changes unless you are prepared to put up with losing infinite focus. The 50mm Compact Macro allows you to shoot at post macro distances something which is quite common if the commons category is anything to go by. On a full frame 50mm also tends to be a bit short for the kind of macro work you might do in a museum. Small items are often far enough back from the glass that something a bit longer comes in handy. The situation with crop sensored cameras is better (75mm equivalent) however I don’t own a crop sensored camera. WikimediaUK does though so I’ve lobbed the lens in their direction if anyone want so try it. Eh if all else fails at f/2.5 it is faster than your standard kit lens.

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Update on Military radio station of Pierre-sur-Haute situation

So some questions have been answered in the French parliament about wikipedia’s clash with the DCRI over the content of the Military radio station of Pierre-sur-Haute article.

Original (in french of course) can be found at:

Hat tip David Gerard

 Looking through google translate it appears that the position of the minister is that the DCRI was justified in what it did (worrying). They did apparently attempt to forward things to the US who told them that the data retention period for something had passed (no mention of the 1st amendment natch). It also appears to confirm that it is Pierre-sur-Haute’s place in the French nuclear weapon control network that has them worried.

There is meant to be some kind of committee delivering a report on the situation at the end of November which I guess is the next time we might hear something.

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Museum photography for wikipedia with the Canon 16-35mm lens

Back when I wrote about the canon 14mm lens I suggested that the Canon 16-35mm would be better for museum photography.

Well I have now purchased on and after some use I have found that in short it is. 16mm is wide enough for most things while at the same time with the limited interior space in museums its uncommon to hit a situation where 35mm isn’t narrow enough. While f/2.8 isn’t up with the speed of fast primes the high ISO performance of modern DSLRs means that it has to get pretty dark before it can’t do the job. The short minimum focusing distance also comes in rather handy when placing the lens against case glass to cut down on reflections. It is L glass so the usual standards of optical and build quality (although I have manage to damage the filter thread on mine) apply.

On the downside the 82mm filter thread is odd but then I wasn’t planning on using any filters with it so not a big deal. The lens speed also needs watching since f/2.8 can often produce a shallower depth of field that would be ideal for wikipedia.

I spent a week visiting various museums and the 16-35mm was the lens that ended up living on my camera. The 14mm saw some use where 16mm wasn’t wide enough and at the other end of the scale Canon’s 24-105mm saw some use. On the other hand my sigma 50mm f/1.4 was only resorted to once. While the lens works best with objects that are fairly large or medium it can produce usable images of small items with a bit of cropping.

All in all for wikipedians with full frame canon camera’s I’d say this is the lens for museum photography.

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Military radio station of Pierre-sur-Haute and wikipedia

So basically the French analogue of MI5 (DCRI) decided that there was something in the French version of the article that was classified and pressurised an admin into deleting it. Fuller story at:

The article has since been undeleted and translated into a number of languages and people are making comments about the probably overrated Streisand effect. Unless there are further developments things have probably settled down for now.

There are however a number of questions. The most obvious being what was the classified information that DCRI were worried about. There’s nothing particularly obvious. Sure it has some involvement with France’s nuclear weapons command and control system but the rather banal information in the wikipedia article doesn’t exactly compromise that. Its possible we are dealing with a situation similar to the one where the existence of the BT Tower was nominally classified and some bureaucrat has taken that a bit far. Still the level of resources used would suggest that we are dealing with more than a single low ranking bureaucrat. Another possibility is that the photo gives something away about the station’s abilities but photos are available from other sources. For the more paranoid (there is an intelligence agency involved) the suggests are that it was either an attempt to confuse other intelligence agencies (although it seems unlikely that they would threaten a civilian with arrest to do that) or an attempt to test a method of removing information from wikipedia.

It should probably be said that the French appear to be far more ready than some to get the police involved with trying to deal with material on wikipedia. Florence Devouard got called in to see the police over a matter involving copyright back in 2008.

As a tactic it may be effective in wikipedias that cover a language which is only really spoken in one country but for more widely spoken languages you are going to tend to hit the problem that there are admins that live outside your jurisdiction.

Strangely at the same time as this has been going on another state has been trying to control the content of wikipedia. In this case it is Russia and it is using the long standing and fairly conventional method of threatening to block the project entirely. I feel that their motivations are also rather more transparent.

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Samyang 800mm MC IF f/8 Mirror Lens

There is a  lens is available from several brands. Mine came from samyang and since it says “Made in Korea” on it they may be the people who make the lens. Samyang have developed a fairly positive reputation of late making cheap but good manual lenses. The Samyang 800mm mirror however comes from a previous generation.

Mirror lenses never really had the best of reputation and to be honest the Samyang 800mm is towards the bottom of the pile. But still 800mm is 800mm right? And at £155 its fairly affordable.

So is it worth it for wikipedians? To be honest probably not. There simply isn’t that much that needs shooting at 800mm. Most of the time its simply a matter of getting closer. Of the stuff there is it generally isn’t too good at that either. If it wasn’t too slow for sports at f8 its fiddly focusing system (¼ of a turn between 3.5m and ∞) makes it pretty much unusable in that area. Wildlife would be a more classic use but the money would probably be better spent joining a birdwatching society. Unless you live outside north America and western Europe your local wildlife has already been well documented by people with more serious kit. Photos taken in zoos and the like fill up a lot of the gaps. That’s not to say that there isn’t still work to do but it will involving going after less common species and given the time and effort required to do that in most cases better kit can be justified. As for astrophotography thanks to NASA and wikipedians with serious gear (yes technically the samayang lens is a Schmidt–Cassegrain telescope however some wikipedians have far better ones and tracker mounts) that area is pretty much saturated. About the only other use is taking photos of things like castles that are on private land making it impossible to get close to them (taking local laws into account obviously).

While the lens isn’t that heavy its fairly large making it unlikely that it is something you would carry around on the off-chance it would come in handy.

Outside of wikipedia’s however things are a bit different. 800mm may not be particularly useful but it is fun particularly once you get past the fiddly focusing system. The build quality is solid enough that you don’t need to worry about it falling apart and the image quality is certainly usable (although the fixed f8 does limit you to bright light only). In fact if you take images beyond 100 meters or so the limiting factor is likely to be the clarity of the atmosphere rather than the lens. If 800mm isn’t enough the T2 mounting system that the lens uses can be used to attached the lens to a micro four thirds system giving you 1600mm equivalent. Why you would want to do this I’m not sure but its not like you have to justify it to anyone. Samyang also sell a x2 extender for the lens although I can’t imagine the results are much good. I did try sticking it on the canon x2 extender but since the extender expects there to be some lens electronics to talk to this doesn’t work.

As with most mirror lenses its worth getting the lens hood with it. Samyang do make a lens hood for the lens (nice solid metal) but I had to phone up the supplier I was using in order to get hold of one. One problem with the lens hood is that since it attaches inside the barrel it is impossible to attach the lens cap while it is in place and the thread on the hood tends to stick making it hard to remove.

Overall the lens scores not so well on the image quality stakes but high on the fun stakes. For wikipedains though there are more useful lenses although not at the same price.

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