Thursday 30 July 2009

SoFoBoMo 2010: learning materials

If you're interested, or participated, in Solo Photo Book Month, then you've probably seen Paul Butzi's announcement about next year's event. And you've maybe seen Colin Jago's call for help with translations.

Another feature for the website that we are planning is learning material to help SoFoBoMoers with various aspects of planning, preparing and completing their photobook. The aim is to have two main parts to this: first a community supported Wiki with lots of useful info on relevant topics, presented in a way useful for the event and second downloadable instructions for various tasks, especially around using appropriate software for making the book. I'll be leading the charge on this front.

Topics that will definitely get covered:

image formats, pdf in general, pdf creation, colour management, book making software (Scribus, Pages, InDesign), layout principles.

But this post is also a call for help on two fronts:
If there are other topics you want covered, drop a comment here which gets published and I'll gather them all up and try and include them in the plan. Was there stuff you wish you'd known in advance? Stuff you still don't know but wish you did?

On the other hand I'm looking for volunteers to help put together material for the site. Got useful tips? Instructions on particular software? Want to help testing the instructions? Found some useful resources that got you through SoFoBoMo? Drop a comment (won't get published) with contact details and I'll get in touch with how you can help. No submissions just yet, just volunteers.

In due course there will be a community editable wiki etc on the website but for now we need to gather initial material to populate it once it's running. And we'll be encouraging translation of that stuff, too.

Amazing things with photography pt2

Photography of wildlife behaviour at its best, courtesy of the Daily Telegraph.

Experiments in JPEG compression


I wrote before about optimising jpeg compression for various output, mainly aimed at single conversion for on-screen view. Then a couple of comments on this post by Colin Jago had me thinking more about using jpeg images.

It was suggested, in reference to making photobooks, that TIFF (by inference, uncompressed images) are needed to retain image quality. I don't do that. when using Scribus I import all images as resized jpegs exported with a quality of 9 from Photoshop or 90 from Lightroom. By working with jpegs I minimise memory requirements and speed up software response. Am I losing quality in doing this?

So I've run a little experiment. I took the image above (selected for a mix of fine detail and smooth tonal areas), from its 16-bit uncopressed TIFF format and successively converted it to jpeg. that is, I converted to jpeg, took that jpeg and converted and so on. I ran 10 iterations. I tried 3 different qualities (90, 75, 50 from Lightroom), no sharpening applied in conversion. This is what I found.

The 10th quality 90 (jpeg 90-10) showed almost no discernible difference to the first jpeg (jpeg 90) which is indistinguishable from the original. That at 100% on-screen view. The one slight difference between jpeg 90-10 and jpeg 90 was slight posterization in the darkest shadows. By slight, I mean peering closely and changing my angle of view a lot. At full-screen view it is unnoticeable. It would not show in a print. Each jpeg in this series is 2.6Mb in size for a 10MP image.

jpeg 90-10 crop, click for 100%

jpeg 90 crop, click for 100%

The same story for jpeg 75-10 compared to jpeg 75. These files are 1.2MB for the same image.

For jpeg 50-10 there is definite loss of detail and a number of strange block artefacts in smooth tone areas. I had to go all the way back to jpeg 50-4 (4th in series) before it was indistinguishable from the original. The files in this series are a mere 581kB.

jpeg 50-10 crop, click for 100%. Notice the weird blocks in the smooth areas

jpeg 50 crop, click for 100%

Conclusion: it is quite feasible to use jpeg for successive output operations without losing detail. For short runs (3 or 4 successive conversions) it is feasible to use quite low quality (high compression) and not lose detail. Higher quality will support longer runs. I haven't yet run the 75 and 90 series to the point that they start to lose quality, that's a job for another day.

Sunday 19 July 2009

A bit of a hiatus

It's not been a terribly good day, Murphy plaguing me all day. Worst of all I've broken my main computer (this come courtesy of my netbook) to the point it won't boot. That's what comes of trying fancy things with moving boot partitions. I reckon it'll take me a few days to recover that lot. Thank goodness for my rigorous back-up system.

Thursday 16 July 2009

PDF: a layman's explanation

As Colin Jago points out, information on PDF formats and content is typically fairly obtuse. Heaven knows why.

Off I went to read the ISO standards to understand this stuff. When one digs in, there are some fairly simple explanations for this all. I shall try and elaborate.

PDF is now defined in a series of international standards and like all standards, they have to cover a wide range of uses and interpretations. Boiling standards to their essence is quite a skill, one which I get to practice frequently on a professional basis.

Essentially PDF breaks into 2 types - the generic document container and the specific print-ready file.

The general types of PDF (1.3, 1.4, 1.6, 1.7 etc) are wide-ranging descriptions of ways of publishing documents for various applications. Basically the standards define a very general container for a whole lot of data types. Some are application specific (e.g. PDF 1.6 is specifically for engineering data).

In their simplest use (and, I suppose, the one with which most people are familiar) they are just a way of formatting text documents in a way that they can be used across a variety of computer systems. In their most complex form they are multi-dimensional, multi-media applications with hyperlinks, cross-document linking, user input, and a variety of interaction capabilities all done in a way that a variety of computer systems can use them.

The standards lay down a whole lot of requirements on document structure and on the readers that present them to you.

In practice things get muddied by non-compliances, bad formatting and odd things getting embedded. Adobe help the user by providing Acrobat Reader with a pile of capability to try and sort the mess out so that you can use the content.

Then there are the PDF/X types. These are simplifications of the main PDF types specifically for printing and incorporating requirements for colour management data. There are basically 2 types, PDF/X-1 which is CMYK only and PDF/X-3 which also allows RGB colour spaces. The PDF/X standards pretty much says: text & pictures only, no fancy stuff, tell us the fonts & colourspace you're using.

The 2 big differences between the two types of PDF (normal and X-type) are

  • PDF/X is a simple, flat file. No layers, hyperlinks, multimedia etc. Just text and graphics for printing on paper.
  • PDF/X requires colour management data embedded so that the printer can print things properly.
There are a few niceties in PDF/X around font management and pre-determined output colourspaces that are best left to the pros with a direct working relationship with their printer.


How does this affect you, the humble photobook writer? In principle, not a great deal. If you're doing a basic photobook and writing a PDF file with embedded fonts, JPEG images with a colourspace and no fancy links, video etc anyway then there is essentially no difference between a PDF 1.3 and a PDF/X-3 file. In fact, there's little difference with PDF 1.4 either (which introduces transparency - if you don't know, you don't need to). Just write a regular PDF and it'll comply with the X-3 format. Or export as an X-3, which should take out any fancy stuff you (or your software) added inadvertently.

I hope that helps.

Movement

Fork in path, Thirlspot, Cumbria, May 2009

As Colin Griffiths comments on my last post, I enjoy the process of lugging a big camera up big hills. But it is results driven. I want movements for angle of view & focal plane control. I want fine detail and smooth tones for large prints.

For the details and tones it is (for me) prohibitively expensive to go digital.
On investigating tilt-shift lenses for 35mm it's becoming clear that the only way to properly do the movements I want is to have a large focus screen.

The more I investigate options, the more I find I have the right one.

I'm thinking of poking around with Helicon Focus, which will be cheaper than a tilt-shift lens, but it can't do some things. Subject movement is an obvious one (and I work quite a lot in windy conditions). Soft clouds is another - I like to use a front tilt to extend depth of field in the land, which helps soften up focus on the clouds. Sure I can do all that in software, and use multiple exposures.

Here's the thing, though. Using movements in the field takes no more time than running a series of careful exposures and the time I need for the final processing is a whole lot less.

Digital solutions? Here's a couple of ideas.
  • Auto multi-focus. I set start and end points for focus and the camera runs a series between them.
  • Digital tilt focus. Can be manual with confirm or auto. Define the points you want in focus and adjust accordingly, just like the manual process. Asymmetric tilt/swing would help a lot for manual (auto can do fancy simultaneous movements). 2 points needed for single-axis movement (tilt or swing), 3 for 2 axes (tilt and swing).
Of course, there is one problem that all this digital stuff doesn't fix: reliance on power in the field. Maybe we'll get really good solar panels that will sort that out too.

Wednesday 15 July 2009

Not at the limit yet

Little Man and Skiddaw, Cumbria, May 2009
Shot on 120 roll film, 6x9 on an LF camera

Those who read the Luminous Landscape have probably seen this article by Ray Maxwell ostensibly on the applicability of Moore's Law to camera sensor development, coming to the conclusion that we're hitting the limit, especially in terms of resolution. The arguments didn't look right to me and this TOP article by Ctein neatly debunks the entire thing.

Even with my moderate grasp of the subjects of optics and digital sampling it didn't take long to confirm that the LL article was wrong and to be able to come up with my own calculations (which turned out to be very similar to Ctein's).

Maxwell omitted the Nyquist-Shannon sampling [WARNING: geeky maths link] limits which means we need pixels at most half the size of the given Airy disc or smaller to get full resolution data. Sensor arrays further reduce the pixel size required in order to sample each frequency. I reckoned we can go down to about 1/4 the given Airy disc limit. Of course Maxwell did his numbers at f/11 which suggests large pixels but optics tend to be optimised for larger apertures, with the photographer accepting the resolution/depth of field trade-off for smaller values. Even if we calculate at f/11, with the 1/4 Airy pixel size then that yields a limit of 1.5micron. For comparison a typical pocket camera 1/1.7", 12MP sensor has a pixel pitch of 2micron, so within the grasp of current technology. Compare that to the current 4-6micron for larger sensors and we could happily go to pixel counts 9-16 times those used today before hitting resolution limits.

So your 22MP 35mm full frame could stretch out to around 200-300MP and still yield noticeable resolution improvement. Another upside of extreme resolution is the ability to crop. I could see an argument for using wider angles and cropping for a lot of shots. Imagine only carrying a wide angle and mid-tele for everything. Shoot 100mm and crop the centre for a 400mm equivalent shot. Monster panoramas in one exposure.

Sufficiency is never enough anyway. The sufficiency argument has been touted since cameras hit 4MP.

And all of that ignores any future technology leaps.

[Hereby rewarding a healthy dose of scepticism and justifying my geek tag]

Monday 13 July 2009

Amazing things with photography

Soap bubble bursting over at the Daily Telegraph.

Saturday 11 July 2009

The naked photographer

I'm just back from a couple of business trips. For the first time in many months I didn't have a camera with me, not even my pocket camera. And it felt odd. For sure there were limited opportunities for photography but I could have made time. Mainly it was just strange not even having the option.

Sunday 5 July 2009

More on natural colour

"This theory of what constitutes fine colour is one of the peculiar traits of the old-time painters, and of the landscape critic who studies nature in the National Gallery...Above all things it must not be natural, or it ceases to be fine and sinks to the level of the commonplace...if one suggests that it has no resemblance to what it claims to represent, they reply, 'Ah, but it is a glorious frame, full of colour!' But colour in painting can only be really fine so far as it is true to nature...Beauty in colour, as in form, depends on its fitness and truth."
T. F. Goodall
quoted by P. H. Emerson in
Naturalistic Photography for Students of the Art. 1889

Emerson continues
The vulgar view of fine colour is easily explained on evolutionary grounds, it is but a harking back to the instincts of the frugivorous apes - our ancestors.

Saturday 4 July 2009

Not the weather for printing

Tree of the field, Swaledale, June 2009

Now that all the book making is over, I've been turning my attention to running some prints and tweaking some of my favourites for paper output. This is an activity nicely timed to coincide with a spell of hot, humid weather. This is not conducive to print making. The humidity seems to cause the printed surface to absorb moisture, causing wrinkling of the paper and that is also leading to some long drying times, despite the heat. How do people in warm climes cope with this stuff?

On the positive side, I'm really happy with the output from my recent work. There are a few tricky images with subtle tones and colours that are taking some effort but most are coming straight out very nicely. My whole process is now driven from Lightroom using the custom profiles I built for my printer/paper combos.

Beauty in chaos

Leaves gathered, Hudswell Wood, Yorkshire, June 2009

Nature presents us not with the random but the chaotic. Structured form from complex interactions. Drawing out that structure in a way that the brain can fathom is the mark of great nature photography.

Thursday 2 July 2009

SoFoBoMo 09: my books, wrap-up

End of the beach, Mundesley, Norfolk, June 2009

I've got there, it's over. Here's a summary of what I did, why I did it and what I learnt along the way (with all the self-promoting links, natch).

Part 1: On England's Pleasant Pastures Seen

Norfolk, May 2009

The first two books have titles inspired by Blake's poem "And did those feet in ancient times" (better known as the hymn Jerusalem), which is evocative of all that is English. This one covers the rural county of Norfolk.

It was designed from the outset as a print book (available from Blurb with a free print offer!) with the unusual aspect of a bottom-edge binding. This is a layout I've been meaning to try for a while. The online pdf version attempts to recreate some of the experience of that format.

All of the photos wee taken using a rangefinder (Zeiss Ikon) on colour negative film (quelle horreur).

Part 2: Upon England's Mountains Green

Blencathra, Cumbria, may 2009

Following on from the rural landscape of Norfolk, this is about the hills of Cumbria. From the outset it was designed as an online book but in a format that could readily be converted to print. I was experimenting with mixing colour and black and white, multi-image pages, background colour and captioning. Variable quality of images but turned out rather better than I had imagined.

All the colour work was with a Panasonic LX3 camera, all the black and white with a 4x5" field camera on Ilford FP4+ roll film.

Part 3: Under English Skies

Swaledale, June 2009

A purely online effort, using images from a photography workshop in Swaledale, Yorkshire. Title comes from my observation that England seems to have very particular skies, which suits the very particular landscape photographed. Some pretty good photos. Book was designed from the outset as a purely online book, taking advantage of variable page sizes etc afforded by a purely electronic format.
However, I think I'll extend this idea into a longer series of my best landscape work from the UK and turn it into a printed version.

Part 4: Seafront

Fishing on the beach, Mundesley, Norfolk, June 2009

Another effort from Norfolk, this time based around the seafront of the village of Mundesley. Again designed as an online "book" but in a very different format, further exploring the unique capabilities offered by electronic presentation. Of course, it could be printed (large) but that isn't really the point.

Both books 3 & 4 were shot entirely with my Canon 40D.

There we have it - four very different books, four different cameras, two different types of film.

Why so much? Partly my travel schedule - 5 trips during the SoFoBoMo period (not all planned at the start) meant I couldn't really focus on a single topic. So I used that to my advantage to explore different ways of doing books and shooting projects.

I've learnt a few things:
Electronic presentation of photo work has its own characteristics. It is possible to produce entirely satisfying work solely for that medium, if one is prepared to think in a different manner to traditional print layout.
Editing is a tricky business - choosing work that fits together is not the same as picking a bunch of good photographs. For this effort I went for first impressions, quick selections, cutting down the time I applied as exploring the form of presentation was more important than content.
Practice with book layout and workflows for preparing images helps. Editing aside, I can easily assemble a book in an evening (3-4h). Good preparation helps: having text written, images processed (but not sized) and a clear idea of layout & storyline are requirements to do things that quickly.
Putting together presentable work takes less effort than one might imagine. While I'm not claiming any of these as works of Fine Art, they're reasonably good and didn't take a huge amount of effort, shoehorned as that was around a busy work & travel schedule.
Shooting with film is not a good idea for large volume or time-pressured work. The camera time is about the same, and I produce less frames but the processing time is high: develop, scan, dust spot, apply corrections, dust spot, prepare for print, dust spot... I do not intend to use film for SoFoBoMo 2010.

Overall it's been fun, it's got me out when I might otherwise have stayed indoors and it's taught me a lot (again) about my photography. It pushed my meagre time-management skills (although I work well to deadlines). I continue to develop the running themes in my work and see some large chunks coming together. And it was fun.

I've now downloaded around 50 of the other books and I'll be posting some comments on them in due course.

Swaledale barn

Swaledale barn walls, June 2009

A picture, as this is a photography blog.

Li-Ion battery management

Colin Jago had a post recently in response to Panasonic's decision to restrict camera battery use to on-brand only through firmware updates. It seems all their firmware updates are getting the treatment. I realised that the opinions (mine included) seemed rather ill-informed conjecture. So off I went to investigate the whole Li-ion thing, this post is the result.

I had two mind beginning this: the cynic in me regarded the Panasonic decision as pure marketing wrapped in a dodgy safety message, the engineer in me wanted to understand the risk and whether I was actually placing myself in harm's way.

I've included some handy references at the end rather than pepper this thing with links. I read a bunch of stuff, the links provided give all the information in a handy to digest form. Of course, you will have to make up your own mind, I cannot be responsible for your actions and I'm not advising anyone to follow my lead. Caveat lector.

Side-bar: testing batteries
Scott Kirkpatrick provided this link to some testing of Olympus batteries which highlights some of the problems. What do these tests show? First that there are products out there that do not have the protections built-in that they should have. Also, that there appear to be many products using common components (partly supporting my theory of limited manufacturers).
What these tests do not show (in any way, as they didn't try) is that the OEM or high-end third party products are any better. By not dismantling the Olympus product they don't support the premise Panasonic is working under that their products are inherently better. There is also no evidence that any particular manufacturer provides a consistently reliable (or unreliable) product, these being single sample tests.

As I see it, there are 4 parts of battery care: charging, handling, storage, device design/usage

There's not a lot a user can do about the last of these, that's just the kit you use. So what about the rest?

Charging - One of the sources of risk in using Li-Ion batteries comes from the battery being over-charged. There are 2 ways this is controlled, through a charging algorithm in the charger which limits the voltage and current during the charge cycle and shuts down the charger when it's done. The second part is an over-voltage protection circuit in the battery should the charger not provide the protection or fail. Both need to fail or be absent to present a failure mechanism.
Handling - carrying, inserting etc. Most batteries have mechanical control to prevent wrong insertion (i.e. the shape of the battery and compartment must match with only one orientation allowed). In order to prevent dangerous failures of the battery out of the equipment, it should be prevented from short-circuit (which seems to present more of a risk than older types due to the internal chemistry) and protection from overheating. Again, batteries should have protection circuits for both of these problems. The US Department of Transport (DoT) rules on carrying batteries in luggage are aimed at minimising the risk of short-circuit by enforcing a carrying method that specifically stops it happening.
Storage - Similar to handling, batteries should be kept from overheating and short-circuit. There is another aspect and that is battery life. The life of Li-Ion batteries is greatly extended by storing them at less than full charge (40% seems typical advice) and at lower temperatures (e.g. refrigerated but not below 0degC).

Low-quality, no-name batteries are more likely to have poor protection circuits which means you are relying more on the charger and device to prevent problems, which increases the risk by increasing the probability of an event happening. The consequences are the same, however.
Side-bar: Panasonic and the Law of Unintended Consequences
I don't know exactly how Panasonic enforces the restriction but i presume it is some sort of electronic tag in the control circuit. Maybe they'll license it to respected manufacturers, maybe not. even if they don't, I expect a bunch of unscrupulous companies to clone their batteries. Likely the sorts of companies that don't include proper protection in their products today and spoof the exterior packaging too. If the technology isn't licensed, then the chance of poor third party products being used goes up as there aren't the reputable ones around. So the problem doesn't go away.

For Li-ion batteries they should have control circuits with over-voltage protection, over-heat protection and short-circuit protection to help minimise the risks from poor handling or usage. It does not eliminate all the risks. But then that is not unique to this particular power source (remember the old, leaky zinc-carbon batteries?).

There is an aspect that I've not talked about, and that is internal failure of the battery. The large laptop battery recall a couple of years ago highlighted this. While the chargers, devices and batteries all had the correct protection circuits all failures came from internal manufacturing defects that were not protected by the circuits. The actual number of failures was low, maybe partly determined by usage pattern as inherent risk. That's easily the biggest case of Li-ion battery dangerous failure and it had little (if anything) to do with usage.

My conclusions: It appears that Panasonic aren't guaranteeing a camera's power usage control, by implicitly requiring the protection circuits in he battery itself. They can't guarantee which charger is used, regardless of battery used, so I presume expect their batteries to provide the protection. The actual chance of failure, regardless of battery type, seems very low indeed. So the decision does not, to me, represent an appropriate response to the risk, they could just as easily have issued an indemnification as part of their warranty. Then there is Law of Unintended Consequences (see sidebar). So, to my mind, this is pure marketing wrapped in a thin safety veneer.

Risks come from: poor charging, easily controlled by using quality product. Short circuit controlled by handling regime (US DoT response is a good, risk-based approach in this regard), poor device control and there we're in the hands of the manufacturer.

My regime: I buy branded non-OEM batteries. They are cheaper but should still be good quality. I avoid the low-quality, bargain priced units. I carry and store them in a protective case and will like now store them in my refrigerator (alongside all that film).

Some links:
Good place to start is (as ever) Wikipedia.
There is a lot of information at Battery University, not just on Li-ion. Specifically they have information on Li technologies, usage and safety. There is also this nice article on Li-ion battery chargers, which explains the best how they work.