4×5 Digital Back Part IV

UPDATE 10/1/16: Check out the latest photos made by a DigiTiler at Digitiler.com

Development of the “DigiTiler” continues into its fourth month. After hundreds of hours and dollars spent on a custom electronic trigger I discovered the 41-cent micro limit switch. After a little work with some pliers and a scroll-saw, I can now quickly fire the A7 shutter at 20mm increments across the horizontal plane.  Here is the front and back of the current prototype.

DigiTiler_Back DigiTiler_Front

The vertical ratchet creates a bit of twisting torque. Attaching the DigiTiler to the Graflex is also a struggle. I go back and forth between holding it on using the Graflex’s slider and strapping it onto the housing. Continuing frustrations aside, the images are getting better.

Here is a test image I’ve set up so you can view through OpenSeaDragon.

Zoom into the pipe to appreciate some of the benefits of large-format digital photography. The image is compiled using 7 rows of 6 images from a Sony A7 camera (42 images total). I use Microsoft’s Image Composition Editor (ICE) to stitch the images together.  For now, ICE is the easiest software to use.

OpenSeadragon is a javascript plugin that expects images in a “deep zoom” format. That is, you must first take your image, in the image above, one that is 300MP large, around 20,000 x 15,000 in dimension, and creates around 6,000 smaller images that the viewer uses to show you whatever part of the image you want to look at.

At first I tried Microsoft’s “Deep Zoom Composer” (DZC) to create these zoomable image sets, but it crashed on my images. It appears Microsoft has given up on this technology and DZC in the new Windows won’t work because DZC was written in the old windows. I’m just guessing of course. Anyway, I stumbled upon VIPS.  Although it’s a command line utility (and the older I get the more I want a GUI) it is simple enough.

vips dzsave [image] [zoom set name]  

In my case that was “vips dzsave J:\Files2016_Maxotics\Photos\20160731Digitiler\Set8\Stitches\DSC05155_stitch_reserver5x7.jpg J:\Files2016_Maxotics\Photos\20160731Digitiler\Set8\Stitches\bricks_dzi.  It then created a bricks_dzi.dzi file and a folder with the 6,331 files in \bricks_dzi.

At first, I tried to upload the files to DropBox.  However, although I know DropBox will work with OpenSeadragon, the upload process was taking hours.  So I used FileZilla to FTP the folder to my server which takes around 20 minutes.   The bad news is I don’t see most photographers using command line scripts and FTP.  Like everything about this project, ANOTHER THING where I need to find an easier way (for non techies).

Here’s another OpenSeadragon example where I didn’t crop the image.

I’m still not getting error-free stitched images.  I’m not sure how much of these errors are mechanical, and how much software.  I’m still hopeful I can get them perfect.

The DigiTiler is getting close to where I would loan one to a photographer with a large-format camera and Sony A7.  If you’re interested and fearless, contact me.


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