Category: Technical

On 30 June there were mass protests in Egypt calling for President Morsi to go, with apparently a majority of Egyptians feeling he had betrayed the trust they put in him at his election. Egyptians in London joined in, several hundred going to the embassy for a noisy protest, and you can see my report and pictures in Morsi must go say Egyptian People.

Among them were many that I recognised from the protests in support of the Egyptian revolution, but it seemed clear to me that there were now more women in Muslim dress than at these previous events. I’m sure that there are Egyptians in London who support Morsi, but at least on this afternoon they were keeping a low profile. One man did come along, together with his wife in black with a baby buggy. I first noticed him talking to the police at the embassy door, then a few minutes later he stood and shouted from the edge of the protest, holding up pictures of the pro-Morsi protests.  I took a picture from where I was with the 18-105mm, then moved through the crowd rapidly towards him. People were shouting back, and by the time I reached him police were leading him away, telling him if he wanted to protest he should do so somewhere else for his own safety.  There were two rather smaller pro-Morsi protests by different groups at the embassy the following weekend, one of which ended abruptly when it was shouted down by people from the other, but I was busy with other issues, But perhaps he came back and joined in then.

It was a densely packed crowd, but a friendly one, with people readily making space for me when I indicated I wanted to move through to take pictures, and I was able to make my way to the centre of where things were happening with little problem. Once there, the most useful lenses were the ultra-wides, both the 16mm end of the 16-35 for a rectilinear view, and the fisheye view – around 140 degrees horizontal – of the 10.5mm, which, as usual I was using as a 16Mp DX lens on the Nikon D800E.

At times the ‘native’ view of this lens, which has a circular feeling, curving the msubject more as you move away from the centre of the image I think really adds to feeling of the crowd, but normally I work with this lens on the assumption that I will correct it to a different perspective. There are various ways you can do this, either using Lightroom’s own ‘lens corrections’, Photoshop and various plugins or other software. I find it best to choose one method and stick with it, keeping in mind the changes it will make when looking through the viewfinder, and my favourite is the ‘Fish-Eye Hemi’ plugin from Image Trends.  Working with this in mind, the huge benefit is that the centre edges of the view finder show exactly what the extent of your frame will be after processing, but you have to remember that you will lose material from each of the 4 corners.

Lightroom’s built-in lens correction is generally hopeless. It defaults to ‘100’ which produces a rectilinear image, but only a smallish rectangle – perhaps a quarter of the image area – is really usable, and most of the image you saw in the viewfinder is simply lost. It actually does rather better if you crop the result from landscape to portrait, as it keeps the mid-top and mid bottom frame edges, resulting in an image in portrait format with around half the original horizontal angle of view.  Sometimes a small value – perhaps 30 – can produce an interesting result, still with a pronounced curvature and also losing 10-15% of the horizontal field of view.

There is also other software that can be used to alter the perspective, including Photoshop itself, and plugins such as Panorama Tools and PTLens, as well as software designed to ‘de-fish’ images for panoramas including PtGui. I think these probably give better conversions to rectilinear than Lightroom but at the expense of a slower workflow.  It’s probably possible to do almost anything with Panorama Tools if you devote sufficient time and effort and become a real geek.

But none of the ways of processing the fisheye images – apart from the ‘Fish-Eye Hemi’ give me something I can really work with predictably when using the camera. If anything the results it gives are more like what I actually see when looking through the camera, as somehow I am less aware of the curvature. The mind somehow corrects much of the ‘distortion’  producing a more natural impression in a rather similar way to the filter. I often mention this filter, and I don’t get paid for doing so – it’s just something that seems unique and works. Everyone with a 10.5mm should try it.

It is generally fairly obvious whether I’ve used the 10.5mm image ‘neat’ or processed in Fish-Eye Hemi in the pictures  in Morsi must go say Egyptian People, but there is a simple way to tell if you are unsure. To apply the filter I first make corrections in Lightroom (particularly for chromatic aberration and fringing which are rather obvious with this lens) including any dodging and burning etc, then export a 16 bit copy to Photoshop to apply the filter. Lightroom renames the exported image, adding the suffix ‘-Edit’ to the filename. Browsers differ slightly, but right-clicking in mine gives an option ‘View image information’ which if chosen brings up a list with the current image name highlighted.
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My London Diary : Buildings of London : River Lea/Lee Valley : London’s Industrial Heritage

All photographs on this and my other sites, unless otherwise stated are by Peter Marshall and are available for reproduction or can be bought as prints.

To order prints or reproduce images

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Bank holidays often rather pass me by. I’m not often working on them – there are seldom many protests taking place and I’ve gone off most of the events that are held on them. But sometimes we take advantage of my elder son being off work to go out on a walk together, especially if the weather forecast is decent – as it was for this year’s Early May bank holiday. The walks, planned by my wife and son, tend to be rather longer than I’d like, and although I like to take a few pictures, my usual camera bag is far too heavy, and this was another good opportunity to familiarise myself with the workings of the Fuji XPro1 and the Fuji XE1.

As usual I was working with raw files, and the settings that I have on Lightroom for importing files seem to me to give colour that is a little too saturated. The picture above was taken with the Fuji 18-55mm lens, and it seems pretty sharp, with very little noticeable distortion for a zoom except at the very widest focal length. This was taken at 25mm (38mm equiv) and looks more or less perfect in this respect.

Working in bright sun, I hadn’t meant to take this at ISO 3200, but given that the ISO was set at 800 and I had (by accident) and exposure correction of -2 stops dialled in, this is what it was. Image quality will have been degraded both by the high ISO, and also by the diffraction of the very small aperture that resulted of f22.  Looking at it on my screen at 1:1 – and examining portions of the almost 50 inch wide image that results on my rather smaller screen (the image is slightly cropped to 4796×3197 and my screen gives roughly 100 px per inch) there is a little noise visible, and a slight softness, but at normal print size the image is hard to fault technically.

So one problem that I have is that that exposure correction is far too easy to turn – this was on the XPro1, but the same is true of the XE1. You do get an indicator in the view, but I’m not very good at seeing such things.

But most of the time I was working with the XE1 with a Nikon adapter and the Nikon 10.5mm fisheye lens.  Its a little odd to use in that the lens at 305 g  weighs almost as much as the camera’s 350 g, and though it seems petite on a Nikon it seems pretty big here. The Nikon G adapter makes it stick out quite a long way more, and has a slider to control the aperture, needed as the lens has no aperture ring.  There are a lot of such adapters advertised on eBay, but those at reasonable prices seem to be of two actual makes, one with silver ridges on a black ring that changes the aperture. The example I bought of that doesn’t give infinity focus at the infinity setting on the 10.5mm, though it seems to work better with some other Nikon lenses. The other, with an all silver ring, works correctly with the 10.5mm.

Neither of them gives you any idea about the actual aperture in use, but you can get a rough idea from the change in the shutter speed. The 10.5 f2.8 works best around f5.6, two stops down, so if you get a shutter speed of 1/1000 indicated wide open, then stopping down until the shutter speed is around 1/250 will achieve this. Any lens used with the adapter of course becomes a manual lens , and the electronic viewfinder image gets dimmer as you stop down.

Once you have set the 10.5mm lens for both aperture and focus (normally at infinity) you seldom need to alter it thanks to the huge depth of field unless your subject is closer than a meter or two. If you set the focus on the camera to M then you can press the control on the back of the camera to zoom in to a highly magnified area of your picture when you do want to focus. As I found to my cost it is essential to check focus in this way; although the image in the viewfinder looked sharp I had it set wrongly for the first dozen or so pictures I took. It may not be easy to get images out of focus with this lens, but I managed it.

Processing is a bit of a pain, particularly as Lightroom 4 doesn’t offer automatic removal of chromatic aberration, which is a shame, as the 10.5mm needs some. You can improve the images by adjusting one of them, then syncing the settings across all of the the 10,5mm pictures – there doesn’t seem any real benefit from individual tweaking.

LR is so far a little of a disappointment for Fuji X users, although the latest version has improved the algorithm used for de-mosaicing the images. But I’m not entirely convinced with how it deals with the colour, and there are no Fuji-X lens profiles available. If I had time I could make my own, and there are profiles available on-line (using the Adobe Profile Downloader) for the 18, 35 and 60mm lenses, but not yet for the 18-55mm zoom.

There is of course a profile for the 10.5mm Nikon, though even when used on the Nikon I’m unsure there is any point in using it. Stupidly it attempts to correct the fisheye perspective to rectilinear as the ‘distortion’ element of the profile, which seldom if ever gives usable results. It isn’t ‘distortion’, but simply a different perspective, and the first thing I have to do is to set that ‘correction’ to zero.

Most of the images I want to run through the Image Trends Fisheye-Hemi plugin – which means exporting them as 16 bit TIFF files with the ProPhoto RGB profile. It adds to processing time and also eats up disk space, with the TIFF files being roughly 4 times the size of the RAW file, adding up to around 100Mb per file.

One of the fairly few non-Fuji lenses available for the Fuji-X cameras is a Samyang 8mm f2.8 fisheye, which also gives an image that fills the frame.  Although as you can see the Nikon does a decent job, I’m thinking about getting the Samyang.  You may wonder – as I did – why it is an 8mm rather than the 10.5, and the answer is that it uses a stereographic rather than an equal area projection (this may help.) The advantage of this is that objects near the edges are less compressed than with the Nikon and should look a little more normal – and with the shorter focal length if you use the Image Trends Fisheye-Hemi plugin you end up with a noticeable wider angle of view – something like 165 degrees horizontal, which may be an advantage. Fewer of the pixels are unused in the conversion which should result in higher quality in the corners of the image.

The Samyang is also a lighter and smaller lens, and has a proper aperture ring which will make it easier to use. As with the Nikon it is manual focus, but you seldom need to focus, and if you do for the occasional very close picture, need to use the magnified view possible in the electronic viewfinder.

I’m still not entirely happy with the Fuji cameras – though I think for most purposes the XE1 works better despite the electronic viewfinder being a poor substitute for a normal visual one. But at times coaxing the XPro1 to actually wake up and take a picture can just be too slow – normally it’s better to leave it switched off, as the start-up time is then faster! There is still something very wrong here, possibly something another firmware upgrade could cure if Fuji took photographers seriously.

Tomorrow’s Bank Holiday I’m still undecided about too. There are a couple of events I’d like to photograph, but it would be nice to go out for another family walk. So I might be using either Nikon or Fuji. Or since I’ve just been over-exerting myself in the garden – and found myself catching a very large holly branch as I pulled it down from the tree where it was held by other branches after sawing it off at the trunk – I may just need to rest with my feet up.

Perhaps there are good reasons why a photographer should sometimes want to limit the flash sync speed of their camera to – for example 1/60s – but I can’t for the moment think of a single one. Any suggestions are welcome.

Of course using slow shutter speeds with synch is at times a useful technique, but something quite different. There is no problem in using flash with a synch setting of 1/250 on an exposure of 30s – and the results would be identical to those with any other synch setting.

Back in the old days, slow sync speeds were often a problem when using flash, particularly once we moved away from flash bulbs to electronic flash. Back in the 1970s, the cameras I was using – Leica M and Olympus – had horizontal travel cloth shutter blinds in its focal plane shutter that could only manage 1/50 and 1/60 respectively. This slow X-sync speed was one of the limitations of the OM series (including the OM4 – my favourite 35mm film SLR – and I still own two, though it’s now probably ten years since I used them) despite its revolutionary (at the time) off the film through the lens flash metering which made flash so much more usable.

Cameras using vertical metal FP shutters had a shorter travel for the blinds and could also manage a faster movement, allowing higher flash sync speeds – often 1/125 in the 1980s, though at the expense of louder and more noticeable shutter noise.

The Nikon D700 (and D800E) offers flash sync in normal X-synch mode at up to 1/250, with special FP modes of 1/250 and 1/320. But custom setting e1 lets you select synch speeds – down to 1/60th. It shouldn’t be confused with CS e2, which sets flash shutter speeds from 1/60s to 30s, as the slowest shutter speed that will be used in P or A modes when using flash.

For normal use on my camera I set e1 at 1/320(FP) and e2 at 1/60. I can’t see any point in using a lower synch speed than the maximum, and I’d like to be able to set a faster slowest speed than Nikon allows to avoid blurring in some images rather than have to remember to do this manually. For most purposes we can simply forget sync speeds now, as these cameras will also synch at higher speeds using ‘Auto FP high speed sync” with the SB800 and other units that implement this though the manual seems very confusing on this. But it just works, even at silly fast speeds like 1/2000. So why have a custom setting at all?

The last few of times I’ve been out working, I’ve been unable to get fill flash to work with the D700, getting over-exposure all the time. It’s taken me quite a while to work out why, though the answer was simple and obvious once I took the time to sit down and think about it. But in the middle of a fast-changing situation you don’t have time to think, and it wasn’t obvious that things were going badly wrong on the kind of occasional quick glimpse at the images on the back of the camera.

When I got home, I’d take a few test images and find that the camera and flash were both performing perfectly, and forget about it. Fortunately it hadn’t been vital to use fill, and I’d got by without it. But this morning I decided I really had to sort it out.

My first thought was that it was a problem with the flash (and I’ve had a lot of problems with flash units, with two needing expensive repairs and a third being being beyond economic repair in the past year.) So I started by resetting all settings on that. I made a few test exposures indoors and things seemed to be fine, so then I went outside where the light was considerably brighter. And noticed that when I turned the flash on the shutter speed dropped right down to 1/60. I couldn’t understand why, nor why their was a ‘HI’ in the control panel – and then I realised.

Most of the time I’ve used flash in recent weeks, a shutter speed of 1/60 has been more or less what I might have chosen if I’d been making manual settings. Possibly 1/125 or even 1/250. But the camera was still set at a high ISO and I was now in pretty bright light – the kind of conditions where I might want to use fill.

I’m sure I didn’t deliberately choose to set 1/60 as my flash sync speed, but possibly did so by mistake, thinking I was setting CS e2. Or just perhaps a load of electrons ganged up on me and decided to change it behind my back. It’s something that often seems to happen when I use the computer, and modern cameras are just computers with a few analogue bits tacked on.

But  I do wonder if the choice of sync settings is one that is there simply because it is easy for Nikon to implement and adds yet another ‘feature’ – even though it makes the manual fatter and understanding and using the camera tougher – or is there really some point to it?

1/60 f4 ISO 1250 flash

Although I don’t much like working after dark, it can often add a little drama to images, and digital cameras work so much better than film in low light. As I’ve often mentioned, the really important thing for me about this is that it enables me to produce much better images with flash.

The protest against vulture funds – companies that have bought up bad debts run up in the past by failed regimes for a small fraction of the original load (in this case the Argentine junta) and pursue their successors in courts around the world for every last penny started as light was fading fast, and I took my first pictures as the protest was starting by available light.

1/60 f4 ISO 1250 no flash

The light was rapidly fading, and soon most of the ambient was coming from street-lights and the windows of shops and offices, and was extremely varied in both quantity and quality.  Most of the pictures I took were using flash, and in the images in Vulture Funds – Claws off Argentina! there are some examples of both ‘good’ and ‘bad’ flash techniques. ‘Bad’ flash is sometimes all you have time to do, when you haven’t got time to do anything but grab the moment, and the obvious defects can sometimes produce interesting results.

So while I dislike the obvious shadow of the placard, the over-lit face of the young girl holding it does make her stand out in a dramatic fashion. Taken with the lens at 18mm (27mm equivalent) she was pretty close to the camera, and was moving around pretty rapidly. My main aim in framing was to include the message of the placard – slightly truncated but it still gets over the message that the vultures should take out their claws – and also I’d been trying hard in other frames to get in the ‘drop the debt!’ message on a number of t-shirts worn by the protesters. But the walker at top right with shoe and saucepan (and the other saucepan) is an example of the little bit of luck we need and just occasionally get.

This was taken in a particularly dark bit of pavement at one edge of the protest, and was one of a series of around 50 pictures I’d made trying to get a strong image from these two kids, who were very playful but extremely uncooperative. I could have posed them – and another photographer did, but that would have lost the incredible energy that I saw. And I don’t do that sort of thing! People posing for me of their own accord I’m happy with.

Of course the picture from the camera didn’t quite look like this. Her face was very close and like the placard needed considerable burning down to give an effect like that I saw, while the young boy’s face was rather darker, and needed some dodging. Using flash often needs quite a lot of post-processing. One thing I missed when doing it on this image was the biscuit in the girl’s mouth, which could have done with rather more toning down.

Another example of flash is this image of the vultures with pans holding the banner. I’d decided to work (as usual) from the side and needed a fairly high viewpoint to see the pans they were banging behind the banner. Flash was essential, but the nearest part of the image was perhaps a couple of feet away from my lens and the furthest perhaps ten or fifteen. Using the inverse square law, the difference in light from the flash would have been in the order of something like 25:1, perhaps 4 or 5 stops.

You can cut down the ratio simply by aiming the flash away to the right, swivelling the head on the SB800 around 45 degrees. I was using the built in diffuser and rather ineffective reflecting white plastic, which gives slightly more even lighting and there was still more than enough light at the left edge of the image. Using a high ISO 3200 also helped, giving a little fill from the street lighting, although most of the light around was actually from the windows behind. Because there was a lot of vigourous pan-bashing happening, I was working at a fairly fast shutter speed – 1/320 – and the results for this particular image would have been better had I thought to move to a slower speed. I’d simply forgotten to do so.

Again, a straight jpeg would have showed much more uneven lighting, and I’ve dodged and burnt to get the result I wanted, rather more like how the scene actually appeared than a completely straight result. I haven’t got it completely right, and the light is still rather uneven. The furthest parts of the image are also noticeably ‘noisier’ as a result of needing to be brightened in post, but the result is still usable.

One of the things I also found it that photographing vultures isn’t too easy. It was very easy to find angles from which vultures don’t really look too much like vultures. I’m rather more used to photographing people – and there are plenty of examples of that to, as well as more in the issue in Vulture Funds – Claws off Argentina!

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My London Diary : Buildings of London : River Lea/Lee Valley : London’s Industrial Heritage

All photographs on this and my other sites, unless otherwise stated are by Peter Marshall and are available for reproduction or can be bought as prints.

To order prints or reproduce images

________________________________________________________

Above is the latest modification I’ve made to my D800E, with a short length of nylon pictures frame cord between the strap slot on the sling strap and the strap ring on the camera body.

It’s very much a stable-door modification after my run for the train on the way home on Saturday resulted in the camera detaching from the strap and bouncing along the platform. Fortunately the camera itself doesn’t appear damaged, as it landed on the flash unit. This broke quite neatly leaving the shoe in the camera and the body of the unit – which appears more or less undamaged skidding along the platform, from where another would-be passenger kindly returned it to me. It looks a fairly simple repair – and putting the two pieces together it still seems to work. The miniature flat cable from the shoe to the body actually looks like it was designed to unplug during this kind of event!

A colleague suggests that a little Loctite on the screw thread would be a good idea, and I don’t often want to remove the sling strap fitting (it takes a tripod screw on the rare occasions I need to use a tripod or monopod.)

I’d realised when I started using the sling strap that there was nothing to stop it coming loose, and added another to my repertoire of many nervous twitches, attempting to tighten it, but had never actually found it needed tightening. Saturday had been a fairly active day, moving around a lot when taking pictures and it had obviously worked loose, with running for the train the last straw.

The nylon picture frame cord is tough stuff – unlikely to break under the weight of camera and flash, leaving it hanging just a few inches lower if the strap becomes unscrewed again. I deliberately have left it loose both to allow the movement the sling strap needs and to avoid chafing.

I like to work with two cameras, and at the moment I have the D700 still on a normal neck strap and the D800E on a sling strap.  I quite like this, as it helps me to tell which camera is which (sometimes a problem for me, particularly as the telephoto lens I use is shorter than the wide-angle) and also helps prevent the banging of the cameras into each other which can result in minor damage.

I didn’t notice any problems working with the cord in place at a protest on Wednesday, so I think its a permanent feature on the camera for me, though I’ll need to watch out for wear.  So as I sat down on the bus to go home, I thought I’d mention it here and put the camera on my knees and took a picture of the modification – heavily cropped above. It was getting dark and it isn’t a high quality image, but it shows the idea clearly enough.

It also told me I had been working with the VR on the 28-105mm lens switched off. I can’t think why this should have been, probably just that I pushed the switch by accident when changing lenses. I don’t think I ever need to switch it off, and it has quite a heavy detent. I hadn’t noticed the images were any less sharp than usual.