I recently got a circa 1978 Soligor C/D 650mm f8.5 mirror lens for cheap at auction. Its has a T mount, and after a cleaning and adding a T-PK adapter, it worked perfectly.
Mirror lenses are not for everyone. Or anyone. At least not these days. They are generally light weight, slow, lack sharpness, and offer busy bokeh. But if you can get one cheap, they can provide some nice images under specific circumstances.
I’ve been playing with hugin to stitch together the dozens of frames for the Egner Memorial Chapel Stained Glass project. During yesterday lunch I shot some material in the front lawn and turned it into a one of those “little planet” images. Here is a screen capture from the preview dialog. A quick hack….
OK, its terrible, and I’ve quickly learned a lot about what the input images need to be. But still, pretty cool! Next time, it will be AWESOME! I’m already addicted to planetoids.
Update: So after rendering this out, and “correcting” the flag in GIMP, and cloning out the tripod on the lawn and some other noodling, I ended up with this:
I consider this to be pretty respectable, considering the input images were not at all what they needed to be. The above image is construced from 5 concentric rings of images, so as we get further out, the overlap issues an parallax issue get to be severe.
The proper way to shoot this is use a wider lens, as a 15mm ( this was shot at 24mm equiv ) an use a single band, ensuring anything architectural is in full fames.
Even so, the Haas building looks plausible, I salvaged the flag nicely, an at least its not egg shaped.
I got married in The Chapel and so it is somewhat special to me. Its a more modern chapel, built in the 1920′s. The stained glass work in the chapel is rather nice, and I think under appreciated. So during break I have been starting work to create some high resolution panoramas:
The stitched image is about 125 megapixels. The above image, to fit here, is about 5 megapixels, so 5x the resolution you are seeing above. There are various image quality issues, but overall the results are rather nice, and certainly better than anything I could do with a single image from any affordable medium format camera.
With a better lens, like a 400mm APO of some sort, I could easily achieve resolutions perhaps 3x higher, or approximately equivalent to a 150 dpi scan of a 2 story tall object.
So how many reducers do you need to attach a thermometer to a boiler? Precisely nine.
The Pentax K-5 includes the ability to perform in-camera correction for geometric distortion and lateral chromatic aberration. Here is an example of both enabled / disabled for the 18-55mm kit lens at 18mm where both distortion and CA are abundant.
Just a quick testimony to old Pentax primes… This is a quick comparison of center and and edge… ( Click on the images to see them full sized. ) First here is the target:
I often see people stacking small numbers of photos in an attempt to improve image quality. Sometimes this works as expected, and other times…. not so much. One of the major issues with this technique is that it can actually yield lower image quality when the individual frames are subject to atmospheric distortions or occasional vibrations in the camera and mount system itself.
[ Left to right: One of the less blurry stills, 100 image stacked, one of the more blurry stills. ]
One of our profs gave me one of these, then one turned up in the DPR Pentax SLR forums. Confirming my theory that some thing spread like viruses, and some like a fungus. The latter being the “yesterday I was unaware they existed, today they are everywhere” emergency pattern.
