Digital BW, The Print

On Dec 10, 2004, at 9:57 AM, Carl Schofield wrote:

>
> Just to follow up on my previous post about stitching, I took some
> comparison shots yesterday at a local waterfall with a 4x5 and a Canon
> 10D.  Here is a side by side comparison of a stitched composite image
> (18 frames (landscape orientation) in a 3 column by 6 row matrix) made
> with the Canon 10D and 135mm f/2 L lens and a scanned (Epson 3200 set
> to produce a 16x2016 bit grayscale at 360 ppi) image from a Polaroid
> type 55 4x5 negative, shot with a Tachihara 4x5 field camera and
> Fujinon A 240mm f/9 lens.  Exposure for the 4x5 was 2 seconds at f/32
> (EI 25) and for the 10D images 1/6 sec f/16 (EI 100).  The comparison
> images are side by side screen grabs in Photoshop at 8, 25, 50 and 100%
> of image size.  The 4x5 image is 83.6 MB and the stitched 10D image is
> 80.1 MB and both are 16 bit gray. The 25% image is approximately the
> appearance when the images are printed at 16x20 inches.  The stitched
> 10D image compares quite favorably to the 4x5, although the stitching
> is very tedious and time consuming.  You would need a 40 MP digital
> camera to get single shot images comparable to the size and quality of
> either the 4x5 or stitched 10D images.
>
> http://homepage.mac.com/scho/forweb/index.htm

Good comparison! Of course many factors at work (different exposure 
times most importantly) but it shows what can be done with stitching.

Just fyi, if you're shooting a lot of panoramas to be stitched, there 
are autostitching possibilities. I see you're on a Mac... you could use 
XPoints (free) and PTMac (not so free) from Kekus.com... for this kind 
of work it's very fast/effective and you shouldn't usually have to do 
much/any manual stitching (unless you have image pairs where there is 
virtually no detail for it to match - like expanses of water). XPoints 
does the job of scanning through your images and generating a PTMac 
project file with control points set for you - then just open in PTMac, 
optimize, and render. Pretty smooth for non-spherical panoramas.

-R