Batch conversion of DNG files to other file types with the Linux command line

At the time of writing, Google Drive is unable to accept DNG files, the Adobe file type for RAW images from digital cameras. The uploads themselves work fine but the additional processing at the end that I believe is needed for Google Photos appears to be failing. Because of this, I thought of other possibilities like uploading them to Dropbox or enclosing them in ZIP archives instead; of these, it is the first that I have been doing and with nothing but success so far. Another idea is to convert the files into an image format that Google Drive can handle and TIFF came to mind because it keeps all the detail from the original image. In contrast, JPEG files lose some information because of the nature of the compression.

Handily, a one line command does the conversion for all files in a directory once you have all the required software installed:

find -type f | grep -i “DNG” | parallel mogrify -format tiff {}

The find and grep commands are standard with the first getting you a list of all the files in the current directory and sending (piping) these to the grep command so the list only retains the names of all DNG files. The last part uses two commands for which I found installation was needed on my Linux Mint machine. The parallel package is the first of these and distributes the heavy workload across all the cores in your processor and this command will add it to your system:

sudo apt-get install parallel

The mogrify command is part of the ImageMagick suite along with others like convert and this is how you add that to your system:

sudo apt-get install imagemagick

In the command at the top, the parallel command works through all the files in the list provided to it and feeds them to mogrify for conversion. Without the use of parallel, the basic command is like this:

mogrify -format tiff *.DNG

In both cases, the -format switch specifies the output file type with tiff triggering the creation of TIFF files. The *.DNG portion itself captures all DNG files in a directory but {} does this in the main command at the top of this post. If you wanted JPEG ones, you would replace tiff with jpg. Shoudl you ever need them, a full list of what file types are supported is produced using the identify command (also part of ImageMagick) as follows:

identify -list format

A Look at a Compact System Camera

During August, I acquired an Olympus Pen E-PL5 and it is an item to which I still am becoming accustomed and it looks as if that is set to continue. The main reason that it appealed to me was the idea of having a camera with much of the functionality of an SLR but with many of the dimensions of a compact camera. In that way, it was a step up from my Canon PowerShot G11 without carrying around something that was too bulky.

Olympus Pen E-PL5

Before I settled on the E-PL5, I had been looking at Canon’s EOS M and got to hear about its sluggish autofocus. That it had no mode dial on its top plate was another consideration though it does pack in an APS-C sized sensor (with Canon’s tendency to overexpose finding a little favour with me too on inspection of images from an well aged Canon EOS 10D) at a not so unappealing price of around £399. A sighting of a group of it and similar cameras in Practical Photography was enough to land that particular issue into my possession and they liked the similarly priced Olympus Pen E-PM2 more than the Canon. Though it was a Panasonic that won top honours in that test, I was intrigued enough by the Olympus option that I had a further look. Unlike the E-PM2 and the EOS M, the E-PL5 does have a mode dial on its top plate and an extra grip so that got my vote even it meant paying a little extra for it. There was a time when Olympus Pen models attracted my attention before now due to sale prices but this investment goes beyond that opportunism.

The E-PL5 comes in three colours: black, silver and white. Though I have a tendency to go for black when buying cameras, it was the silver option that took my fancy this time around for the sake of a spot of variety. The body itself is a very compact affair so it is the lens that takes up the most of the bulk. The standard 14-42 mm zoom ensures that this is not a camera for a shirt pocket and I got a black Lowepro Apex 100 AW case for it; the case fits snugly around the camera, so much so that I was left wondering if I should have gone for a bigger one but it’s been working out fine anyway. The other accessory that I added was a 37 mm Hoya HMC UV filter so that the lens doesn’t get too knocked about while I have the camera with me on an outing of one sort or another, especially when its plastic construction protrudes a lot further than I was expecting and doesn’t retract fully into its housing like some Sigma lenses that I use.

When I first gave the camera a test run, I had to work out how best to hold it. After all, the powered zoom and autofocus on my Canon PowerShot G11 made that camera more intuitive to hold and it has been similar for any SLR that I have used. Having to work a zoom lens while holding a dinky body was fiddly at first until I worked out how to use my right thumb to keep the body steady (the thumb grip on the back of the camera is curved to hold a thumb in a vertical position) while the left hand adjusted the lens freely. Having an electronic viewfinder instead of using the screen would have made life a little easier but they are not cheap and I already had spent enough money.

The next task after working out how to hold the camera was to acclimatise myself to the exposure characteristics of the camera. In my experience so far, it appears to err on the side of overexposure. Because I had set it to store images as raw (ORF) files, this could be sorted later but I prefer to have a greater sense of control while at the photo capture stage. Until now, I have not found a spot or partial metering button like what I would have on an SLR or my G11. That has meant either using exposure compensation to go along with my preferred choice of aperture priority mode or go with fully manual exposure. Other modes are available and they should be familiar to any SLR user (shutter priority, program, automatic, etc.). Currently, I am using bracketing while finding my feet after setting the ISO setting to 400, increasing the brightness of the screen and adding histograms to the playback views. With my hold on the camera growing more secure, using the dial to change exposure settings such as aperture (f/16 remains a favourite of mine in spite what others may think given the size of a micro four thirds sensor) and compensation while keeping the scene exactly the same to test out what the response to any changes might be.

While I still am finding my feet, I am seeing some pleasing results so far that encourage me to keep going; some remind me of my Pentax K10D. The E-PL5 certainly is slower to use than the G11 but that often can be a good thing when it comes to photography. That it forces a little relaxation in this often hectic world is another advantage. The G11 is having a quieter time at the moment and any episodes of sunshine offer useful opportunities for further experimentation and acclimatisation too. So far, my entry in the world of compact system cameras has revealed them to be of a very different form to those of compact fixed lens cameras or SLR’s. Neither truly get replaced and another type of camera has emerged.

A display of brand loyalty

Since 2007, my main camera has been a Pentax K10D DSLR and it has gone on many journeys with me. In fact, more than 15,000 images have been captured with it and I have classed it as an unfailing servant. The autofocus may not be the fastest but my subjects tend to be stationary: landscapes, architecture, flora and transport. Even any bus and train photos have included parked vehicles rather than moving ones so there never have been issues. The hint of underexposure in any photos always can be sorted because DNG files are what I create, with all the raw capture information that is possible to retain. In fact, it has been hard to justify buying another SLR because the K10D has done so well for me.

In recent months, I have looking at processed photos and asking myself if time has moved along for what is not far from being a six year old camera. At various times, I have been looking at higher members of the Pentax while wondering if an upgrade would be a good idea. First, there was the K7 and then the K5 before the K5 II got launched. Even though its predecessor is still to be found on sale, it was the newer model that became my choice.

Pentax K5-II

My move to Pentax in 2007 was a case of brand disloyalty since I had been a Canon user from when I acquired my first SLR, an EOS 300. Even now, I still have a Powershot G11 that finds itself slipped into a pocket on many a time. Nevertheless, I find that Canon images feel a little washed out prior to post processing and that hasn’t been the case with the K10D. In fact, I have been hearing good things about Nikon cameras delivering punchy results so one of them would be a contender were it not for how well the Pentax performed.

So, what has my new K5 II body gained me that I didn’t have before? For one thing, the autofocus is a major improvement on that in the K10D. It may not stop me persevering with manual focusing for most of the time but there are occasions the option of solid autofocus is good to have. Other advances include a 16.3 megapixel sensor with a much larger ISO range. The advances in sensor technology since when the K10D appeared may give me better quality photos and noise is something that my eyes may have begun to detect in K10D photos even at my usual ISO of 400.

There have been innovations that I don’t need too. Live View is something that I use heavily with the Powershot G11 because it has such a pitiful optical viewfinder. The K5 II has a very bright and sharp one so that function lays dormant, especially when I witnessed dodgy autofocus performance with it in use; manual focusing should be OK, I reckon. By default too, the screen stays on all the time and that’s a nuisance for an optical viewfinder user like me so I looked through the manual and the menus to switch off the thing. My brief flirtation with the image level display met an end for much the same reason though it’s good that it’s there. There is some horizon auto-correction available as a feature and this is left on to see what it offers since there have been a multitude of times when I needed to sort out crooked horizons caused by my handholding the camera.

The K5 II may have a 3″ screen on its back but it has done nothing to increase the size of the camera. If anything, it is smaller that the K10D and that usefully means that I am not on the lookout for a new camera holster. Not having a bigger body also means there is little change in how the much camera feels in the hand compared with the older one.

In many ways, the K5 II works very like the K10D once I took control over settings that didn’t suit me. Both have Shake Reduction in their camera bodies though the setting has been moved into the settings menu in the new camera when the older one had a separate switch on its body. Since I’d be inclined to leave it on all the time and prefer not to have it knocked off accidentally, this is not an issue.  Otherwise, many of the various switches are in the same places so it’s not that hard to find my way around them.

That’s not to say that there aren’t other changes like the addition of a lock to the mode dial but I have used Canon EOS camera bodies with that feature so I do not consider it a step backwards. The exposure compensation button has been moved to the top of the camera where I found it very easily and have been using perhaps more than on the K10D; it’s also something that I use on the G11 so the experimentation is being brought across to the K5 II now as well. Beside it, there’s a new ISO button so further experimentation can be attempted with that to see how it does.

If I have any criticism, it’s about the clutter of the menus on the K5 II. The long lists through you scrolled on the K10D have been replaced with a series of extra tabs so that on-screen scrolling is not needed as before. However, I reckon that this breaks up things too much and makes working through the settings look more foreboding to anyone who is not so technical in mindset. Nevertheless, settings such as the the type of file to capture are there and I continue to use RAW DNG files as is usual for me though JPEG and Pentax’s own RAW format also are there. For a while, I forgot to set the date, soon found out what I did and the situation was remedied. The same sort of thing applied to storing files in different folders according to the capture date. For my own reasons, I turned this off to put everything into a single PENTX directory to suit my own workflow. My latest discovery among the menus was the ability to add photographer and copyright holder information to the EXIF metadata attached to the image files created by the camera. With legislative proposals that dilute the automatic rights of copyright holders going through the U.K. parliament, this seems a very timely inclusion even if most would prefer that there was no change to copyright law.

Of course, the worth of any camera is in the images that it produces and I have been happy with what I have been getting so far. The bigger files mean less images fit on a memory card as before. Thankfully, SDHC card capacities have grown even if I don’t wish to machine gun my photography altogether. While out and about, I was surprised to apertures like F/14 and F/18 when I was more accustomed to a progression like F/11, F/13, F/16, F/19, F/22, etc. Most of those older values still are there though so there hasn’t been a complete break with convention. The same comment applies to shutter speeds where ones like 1/100 and 1/160 made there appearance where I might have expected just ones like 1/90, 1/125, 1/250 and so on. The extra possibilities, and that is what they are, do allow more flexibility I suppose and may even make it easier to make correct exposures though any judgement of correctness has to be in the eye of a photographer and not what a computer algorithm in a camera determines. For much of the time until now, I have stuck with an ISO of 400 apart from a little testing in a woodland area of an evening soon after the camera arrived.

Since the K5 II came my way a few months ago, I have been meaning to collect my thoughts on here and there has been a delay while I brought mu thinking to a sensible close.At one point, it felt like there was so much to say that the piece became larger in my mind that even what you have been reading now. After all, there are other things that I can adjust to see how the resulting images look and white balance is but one of these.The K10D isn’t beyond experimentation either, especially since I discovered that shake reduction was switched off and it has me asking if that lacking in quality that I mentioned earlier has another explanation. Of course, actually making use of my tripod would be another good suggestion so it’s safe to say that yet more photographic explorations await.

Dispensing with temptation

The compact system camera arena is a burgeoning one with many manufacturers having followed Olympus into the fray. In latter months of last year, Nikon finally took the plunge though Canon have yet to do the same. Seeing offers on Olympus E-PL1 kits with a 14-42 mm zoom lens had me tempted, particularly with a price tag of the order of £250. In fact, I even got to looking into the competition too and a shortlist emerged. This also featured the Samsung NX-11 and the Sony NEX-C3 as well as the big brother of the latter, the NEX-5N.

What eventually countered the allure of shiny objects was the question as to why I needed such an item. After all, I already possess a Pentax K10D DSLR and a Canon Powershot G11 and these have been satisfying my photographic needs for a while now. The DSLR may date from 2007 but it is still working well for me and, if it ever needed replacing, I’d be going for another Pentax with the K-5 being a strong contender. The Canon is doing what’s asked of it so the recent launching of the G1 X isn’t so tempting either.

The whole dalliance has me wondering about how photographic equipment changeovers come about. After all, it was around a decade ago with the DSLR revolution was in the offing if not in progress. Until then, film photography was predominant but it looks as if it got as far as it could from a technological point of view when I look back at what happened. The digital photography area was new and untapped so moving there offered new possibilities and purchases more easily justified. The end result is that very few film cameras are being made nowadays. Ironically, it’s film photography that now is untrammelled terrain for many and it is holding its own too in an era when digital photography predominates.

The same sort of newness that came with digital photography also applies to CSC‘s to a certain extent. From the heritage of half-frame 35 mm film photography, Olympus has fashioned a different type of digital camera: essentially a compact with interchangeable lenses. Was it the fact that I have no CSC that caused me to be tempted and has it happened to others too? Also, is that what got digital photography going in the first place?

It almost feels as if camera manufacturers have to keep bringing to market new models and new types of camera in order to stay in business. After all, Minolta had to sell its camera division to Sony when they failed to get going in the DSLR market quickly enough. The same thing might have happened to Pentax too with the marque passing to first to Hoya, and then to Ricoh after the firm lost its independence.

What doesn’t help is the lack of longevity of camera models. The coming of digital photography has exacerbated this situated with models being launched at a frenetic rate. In the days of film photography, a model could last on the market for a few years and there was once a time when a twenty year lifetime wouldn’t have looked so ridiculous though there were incremental improvements made over that time too. For instance, a Pentax K1000 wouldn’t be exactly the same at the end of its production run as it was at the start though the model number may be the same. That world is gone.

Camera types have done better with the SLR design lasting around 50 years so far. However, mirror-less camera technology is adding pressure like never before. Even compact cameras allow live TTL type viewing and Olympus dug into its film camera heritage to add an interchangeable lens mount to give us the first E-P1. The original PEN cameras were half-frame 35 mm affairs and, appropriately enough, their descendants have small sensors in the micro four thirds mould. Then, there’s Sony’s efforts with translucent mirrors that do not move like their SLR counterparts. Canon tried this in the 1980’s with film cameras but never pursued the genre. After that, there are mirror-less SLR-style cameras from Samsung and Panasonic that make you wonder if a full size equivalent is in the offing with live viewing and an electronic viewfinder. Olympus is doing a teaser advertising campaign at the moment and it has some wondering if an OM-D is in the offing.

In parallel with all this, Sony is making a good impression with their CSC’s, the NEX series. These have APS-C sized sensors like many DSLR’s and in compact bodies as well. However, the feel very much is that of a compact camera and some have complained of a like of buttons on them though the photographic quality is very good. Samsung have gone for the same sensor size in their NX-11 thought they have gone for SLR styling. That may be more suitable for some than having to find settings buried in menus.

In summary, we are in an exciting if unnerving time in camera technology at the moment. On one hand, we are seeing a great deal of miniaturisation and what formerly were still cameras can do movie making as well. The latter may not be an interest of mine and it looks like a time-consuming hobby too. A lot is in flux right now and a recent court case reminded us of the difficulties in doing original work these days with image processing in Photoshop forming the basis of a victorious copyright claim. Because the number of images that are getting created everywhere, it could be hard for some to avoid this one and that could be exacerbated if the government changes the law so that intellectual property claims can be processed in the small claims courts. That sort of thing makes film photography seem attractive and it does seem that it isn’t disappearing either, even if Kodak has its financial problems. Novelty seems to change photographic tastes and it seems that film photography is novel again. It’s a changing world and who knows where it take us. Maybe a new DSLR body might make a good purchase in case CSC’s usurp their place entirely. Photographic technology is interesting yet again.

Extending ASUS Eee PC Battery Life Without Changing From Ubuntu 11.04

It might just be my experience of the things but I do tend to take claims about laptop or netbook battery life with a pinch of salt. After all, I have a Toshiba laptop that only lasts an hour or two away from the mains and that runs Windows 7. For a long time, my ASUS Eee PC netbook was looking like that too but a spot of investigation reveals that there is something that I could do to extend the length of time before the battery ran out of charge. For now, the solution would seem to be installing eee-control and here’s what I needed to do that for Ubuntu 11.04, which has gained a reputation for being a bit of a power hog on netbooks if various tests are to be believed.

Because eee-control is not in the standard Ubuntu repositories, you need to add an extra one for install in the usual way. To make this happen, launch Synaptic and find the Repositories entry on the Settings menu and click on it. If there’s no sign of it , then Software Sources (this was missing on my ASUS) needs to be installed using the following command:

sudo apt-get install software-properties-gtk

Once Software Sources opens up after you entering your password, go to the Other Software tab. The next step is to click on the Add button and enter the following into the APT Line box before clicking on the Add Source button:

ppa:eee-control/eee-control

With that done, all that’s need is to issue the following command before rebooting the machine on completion of the installation:

sudo apt-get install eee-control

When you are logged back in to get your desktop, you’ll notice a new icon in your top with the Eee logo and clicking on this reveals a menu with a number of useful options. Among these is the ability to turn off a number of devices such as the camera, WiFi or card reader. After that there’s the Preferences entry in the Advanced submenu for turning on such things as setting performance to Powersave for battery-powered operation or smart fan control. The notifications issued to you can be controlled too as can be a number of customisable keyboard shortcuts useful for quickly starting a few applications.

So far, I have seen a largely untended machine last around four hours and that’s around double what I have been getting until now. Of course, what really is needed is a test with constant use to see how it gets on. Even if I see lifetimes of around 3 hours, this still will be an improvement. Nevertheless, being of a sceptical nature, I will not scotch the idea of getting a spare battery just yet.