Archive for the ‘Scribbles’ Category
Although I haven’t mentioned Pygmyfoto lately on this blog, I keep tinkering with the application in my spare time. So I thought I’d post a brief update on my progress.
- The most important news is that Pygmyfoto now can handle single quotes in titles and descriptions. I’m still trying to figure out how to implement escaping for quotes, though.
- The application now properly processes empty EXIF values (useful for publishing scanned images).
- Global settings have been moved to the separate config.php file, which makes it more convenient to tweak Pygmyfoto.
- As you can see from the screenshot, Pygmyfoto now features not a no-frills star rating system based on a simple PHP script.
- Pygmyfoto is now able to log basic visitor info (IP address, visited page, and date/time) in the ip.log file. You can think of it as a poor man’s web stats solution.
- Finally, I’ve added rudimentary support for RSS: the rss.php script automatically generates an RSS feed for Pygmyfoto. The script is far from perfect, but it’s a start.
As always, you can download the latest release of Pygmyfoto from the project’s GitHub repository. You might also want to drop by dmpop.homelinux.com/pygmyfoto to my own Pygmyfoto instance running on Raspberry Pi.
Besides this blog and Google+, I publish my photos on a Pygmyfoto instance running on Raspberry Pi at my home. Instead of integrating Pygmyfoto with a third-party web stats application like Piwik, I opted for a less complex, but more colorful solution based on the nifty BlinkStick LED kit.
If you are interested in the nitty-gritty, you might want to read the Using BlinkStick with Raspberry Pi article by yours truly. In the meantime, drop by my Pygmyfoto installation and give me a blink. ;-)
Thinking about dipping your toes into the film photography waters? An article series published on the Japan Camera Hunter blog can be a good starting point for your adventures in analog:
This is a good weekend read with plenty of useful info.
I always wanted to take a decent photo of the facade featured in today’s photo, but because the building stands on a very narrow sidewalk and faces a rather busy street, there is almost no room for maneuvering. The only option is to shoot from across the street.
Fortunately, I got a rather obscure Tamron CZ-715 70-150mm f/3.8 Adaptall lens as a freebie. It has been sitting idly on a shelf, until I decided to give it a go. This unassuming lens turned out to be quite alright. It’s compact and relatively lightweight, especially compared to Tamron 70-210 which weights a ton. More importantly, 150mm was just enough to shoot the facade from a longer distance. Now that this lens has proved its worth, I plan to use it more often.
Taken with Nikon F-501, Tamron 70-150mm f/3.8 Adaptall, and Ilford XP2 Super 400.
If you want to keep your photos safe when travelling, you don’t need to schlep a notebook or netbook around: an Android device can be used to pull photos from the camera’s storage card and back them up on an external hard disk or upload them to a cloud storage. The easiest solution is to use a USB On-The-Go (OTG) cable to connect an external storage device like a portable hard disk or a high-capacity USB stick and use them for storing backup copies of the photos. However, this approach requires an Android device which supports the USB OTG functionality, and not all smartphones and tables do that. This also means that you have to remember to pack yet another piece of hardware. An alternative solution is to set up a wireless backup system which enables you to seamlessly back up photos on a remote storage device or service using your Android device. Here is how this can be done.
The first piece of the puzzle is a Wi-Fi-enabled SD card. Eye-Fi is probably the most popular choice, but there are other Wi-Fi SD cards out there, including Transcend Wi-Fi SD card, Toshiba FlashAir, ez Share, and PQI Air. I use an Eye-Fi Pro X2 16GB SD card and the accompanying Eye-Fi Android app. The card is configured to use the Direct Mode, so it automatically connects to the camera and downloads RAW files to the Android device.
Another important component is an Android app that takes care of backing up the transferred photos to an SD card and a remote server. There are several apps in the Google Play Store that can do the job, but you can’t go wrong by choosing FolderSync. This app can handle a wide range of protocols, including SFTP, FTP, WebDAV, and SMB. In addition to that, the app supports popular cloud-based storage services, such as Amazon S3, Dropbox, Google Drive, and Box.net. All you need to do is to configure FolderSync to push the photos from your Android device to a server or service of your choice. The described backup solution does have its weaknesses, though. The amount of storage available for backup is limited to the free space on your Android device. You can, of course, use a microSD card for backups (provided the Android device has a microSD card slot), and replace the card when it gets full. Also, uploading photos to a remote server or storage service requires a relatively fast and stable connection which might not be readily available at your travel destination.
A new release of the Instant Guide to DSLR Dashboard is available for your reading pleasure. In addition to minor tweaks and improvements, this version of the guide includes information on setting up wireless tethering and using Raspberry Pi as a DSLR Dashboard server.
If you’ve already purchased Instant Guide to DSLR Dashboard, you can download the new version as described in the guide.
Our garden residents provide ample opportunities to make use of my Tamron SP 300mm f/5.6 Adaptall 2 lens mounted on a Canon EOS 1100D. Most of the time, I have to shoot through the thick double-layer glass of a terrace door, but I managed to capture this photo through an open window on the second floor of our apartment. This is, by the way, our blackbird named Haru. These days, he is busy feasting on apples we put for him and his lady (more about her in another post) and patrolling his territory, a.k.a. our garden.
Sunday wasn’t a very good day for him, though. After he took a bath in a plastic tray we put for that purpose, the poor bugger flew right into the glass terrace door. He hid then in a corner of the garden, and sat there for a while slightly confused. He is alright now, dashing around the garden and looking busy as usual.
Taken with Canon EOS 1100D and Tamron SP 300mm f/5.6 Adaptall 2. Processed in digiKam. Shutter speed: 1/250 sec. Aperture: f/5.6 ISO: 400
The Sharpen tool in digiKam offers three sharpening methods: simple sharp, unsharp mask, and refocus. Each method has its advantages and drawbacks. The simple sharp technique uses a standard convolution matrix algorithm to improve image details. If you are curious about the nitty-gritty of the convolution matrix, the GIMP documentation provides a brief description of the algorithm. In fact, the simple sharp tool in digiKam is ported from the GIMP project. The main advantage of the simple sharp method is its simplicity. The Simple Sharp tool in digiKam has only one adjustable parameter called Sharpness which determines the strength of the applied sharpening filter. On the downside, the simple sharp method doesn’t handle image noise very well: it tends to introduce more noise in photos taken at lower ISO settings.
Unsharp mask is a popular sharpening method which sharpens the edges of the elements without increasing noise. The unsharp mask technique creates a slightly blurred version of an image, which is then subtracted from the original in order to detect edges. The resulting mask is then used to increase contrast along the detected edges to produce a sharper final image. The Unsharp Mask tool in digiKam has three adjustable parameters:
Radius specifies how many pixels on either side of an edge will be affected by sharpening. High-resolution photos allow higher radius.
Amount determines the strength of sharpening.
Threshold specifies the minimum difference in pixels that indicates an edge where sharpen must be applied. This lets you protect areas of smooth tonal transition from sharpening, and avoid creating blemishes in face, sky or water surfaces. 
When using the unsharp mask tool, you should keep in mind that it can introduce subtle color shifts and halo artifacts visible as dark or light outlines near edges.
Finally, the Refocus method is based on the Refocus plugin for GIMP which uses a technique called FIR Wiener filtering to sharpen the image (see http://en.wikipedia.org/wiki/Wiener_filter). Similar to the original plugin, the Refocus tool in digiKam offers several adjustable parameters:
Circular sharpness is a key parameter which determines the radius of the circular convolution. Basically, it specifies the strength of the refocusing action.
Correlation helps to reduce artifacts. Increasing the correlation value reduces the sharpening effect. Useful values are 0.5 and values close to 1 (e.g., 0.95 and 0.99).
Noise filter may help to reduce artifacts. Similar to the Correlation parameter, increasing the noise filter value reduces the sharpening effect. A useful value is 0.01.
Gaussian sharpness is used to specify the radius of the Gaussian convolution for correcting Gaussian blur. In most cases, it should be set to 0, as it introduces artifacts. When using non-zero values with Gaussian sharpness, you might need to increase the Correlation and Noise filter parameters, too.
Matrix size determines the size of the transformation matrix. Increasing this parameter may give better results, especially when large values are chosen for the Circular sharpness or Gaussian sharpness parameters. In most cases, you should select a value in the range 3-10. 
Refocus is the most powerful and effective sharpening tool in digiKam’s arsenal, as it not only offers a superior sharpening method and granular controls, but can also handle noise.
 Source: http://refocus.sourceforge.net/
It all started with a Tamron 70-150mm f/3.8 CZ-715 Adaptall lens I got thrown in as a freebie when I bought my Nikon F-301. Although I had a vague idea of the Adaptall technology, I knew nothing about this particular lens. While doing research on the lens, I discovered that Tamron had a strong product line of the SP series Adaptall 2 lenses targeted at serious amateurs and professional photographers. One lens, in particular, piqued my interest: Tamron SP 300mm f/5.6 Adaptall 2 54B. While this model is a bit slow, it has an impressive 300mm focal length and features 1:3.3 macro capabilities. More importantly, the lens is rather inexpensive, and I’ve managed to find a unit in excellent condition at a very reasonable price on a local online auction.
Tamron also produced a 2x converter for use with Adaptall 2 lenses, and I was lucky to find one on eBay. This converter doubles the focal length, but it does so at the expense of the aperture. So the converter transforms a Tamron SP 300mm f/5.6 into a 600mm lens with the maximum aperture of f/11. Tamron lenses with the Adaptall 2 adapter for Nikon F mount are compatible with Nikon’s analog and digital SLRs. When bolted onto a Nikon DSLR with a DX sensor, the lens’ focal length equals 450mm. Add the 2x tele converter, and you get an whopping 900mm focal length.
To test the lens, I went to our local botanical garden. I started with my Nikon F-501 film SLR loaded with Fujifilm Fujicolor C200.
I also tried the lens with my trusty Nikon D90 DSLR. Using Tamron Adaptall lenses on a modern DSLR is only possible in the Manual mode. The camera can’t read aperture values either, and you have to switch to manual focusing. In other words, shooting with the Tamron SP 300mm f/5.6 Adaptall 2 lens is a full-manual affair. On the positive side, focus confirmation seemed to work just fine.
So how did the lens perform? For its age, the lens did admirably well. Sharpness is good, and the lens produces pleasing and creamy bokeh. Overall, it’s not so shabby for a twenty-something-year old lens, especially considering the price.
By the way, if you are looking for information about Tamron’s Adaptall lenses, the Adaptall-2.org website got you covered.
Install the DSLR Dashboard app on your Android device, and you can use it to control a Nikon DSLR camera via a USB connection. But in certain situations, tethering the Android device to a camera using a cable is not ideal. This is where DSLR Dashboard’s wireless functionality can come in rather handy. Using this feature, you can link up two Android devices running the app via a Wi-Fi connection. In this case, the device connected to the camera acts as a wireless bridge (or client in DSLR Dashboard’s terminology) between the camera and the master (or server) Android device. And the latter is used to control the DSLR camera remotely. Here is a diagram that illustrates this setup:
- Nikon DSLR camera
- Android device running DSLR Dashboard that acts as a client
- Wi-Fi access point (AP)
- Android device running DSLR Dashboard that acts as a server
As shown on the diagram, both devices must be connected to the same AP. Instead of using a regular wireless router, you can opt for a mobile router like TP-LINK TL-MR3020 to make the entire setup portable. The clever part is that many mobile routers can be powered via a generic power adapter which can be bought cheaply on eBay. This allows you to create a wireless network whenever and wherever you need it and use it to link Android devices running DSLR Dashboard.
To set up this portable wireless remote control solution, you need the following items:
- Two Android devices running Android 2.3 or later
- A USB OTG cable (can be bought cheaply on eBay)
- A USB cable supplied with your DSLR camera
- A mobile wireless router like TP-LINK TL-MR3020
- A battery power adapter
Power up the mobile wireless router and configure it as an AP (consult your router’s documentation on how to do this). Connect the Android device that will act as a server (i.e., the device for controlling the DSLR camera) to the wireless network created by AP. Tap the Menu button and choose the Start Network Server command. Connect the other Android device to the DSLR Camera using the USB OTG and the USB cables. Enable Wi-Fi on the device and connect it to the wireless network created by AP. Turn the DSLR camera on and launch the DSLR Dashboard app. Once the app has detected the camera, tap Menu and choose the Start Network Client command. This should automatically hand over control to the server device which you can then use to operate the DSLR camera in the usual manner.