Brian, are you counting on some precision in the x-y positioning of the film (or camera)?Originally Posted by Brian C. Miller
Brian, are you counting on some precision in the x-y positioning of the film (or camera)?
Mike → "Junior Liberatory Scientist" ✌
The problem AISI with the enlarger scenario as I see it is that a) then you would have to focus with it tethered-not a huge issue and b) more importantly you would have to move the camera to create the tiles rather than the negative. Personally I think it would be easier and more solid to have the camera fixed and move the negative.
Thanks,
Kirk
at age 73:
"The woods are lovely, dark and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep"
Earlier postings mentioned dof in the microns for the moving neg, I don't see that as easy compared to getting a sliding camera table to within 1mm.
If I remember rightly, the 20 micron range of depth of field is only for higher magnifications than we're looking at here.
Btw, I ordered a sync cord for my SB-28, and it came in the mail just now. It has a threaded PC connector. I wish I would've known about those a long time ago. I absolutely despise non-threaded pc connectors.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Jumping in late here, but Kodak invented and marketed a scanner c.1991, called the PIW (Photo Imaging Workstation). that essentially had a camera on a stand and used a moving scanner bar beneath the negative. It would do up to 5x7 and some aerial film, and used a Schneider Makro-Componon lens. As well as a Sun SparcStation 20 computer to run it. As this was pre-Photoshop it had its own image-editing software, and would write the finished files to a Photo CD. I scanned thousands of images with one when I worked for Kodak- it did a fine job but I can't now remember its resolution capabilities. That machine lasted until about three years ago when mechanical issues doomed it for good. God only knows what it cost to design, and of course I never knew what EK sold them for (or how many), but the idea could be updated with modern computers and perhaps be affordable.
You mean like a stepper motor? Or using an encoder wheel?
Yes. Everything has some precision. How precise does it need to be to accomplish a specific task?
Even moving the camera on a plane by hand according to a cheap machinist's ruler would result in a set of images that will have enough accuracy for stitching in an area with no landmarks. The human eye really can distinguish tiny gaps, and that's more than enough for a prototype.
Stitching software is designed for joining images which have an extremely wide variance of sampling accuracy. The commercial software is advertised as being able to construct an image from a hand-held camera. The project goal is a camera on a computer-controlled X-Y axis. The computer moves the camera, triggers the shutter, downloads an image, and repeats until done. After that the images are stitched.
"It's the way to educate your eyes. Stare. Pry, listen, eavesdrop. Die knowing something. You are not here long." - Walker Evans
Thanks! No free lunch as usual.
Imagine an image of a completely uniform sky with a bird in it, the bird is the only landmark. The bird ends up in the middle of a tile.
It sounds like the precision of the placement of the bird in the stitched image depends on the precision of the film/camera placement during capture. True?
(I'm not saying this is inadequate just trying to clarify.)
Mike → "Junior Liberatory Scientist" ✌
I just did a test using my D200 (ISO 100), Nikkor 55mm (F5.6), at 1:1 with a negative illuminated by an SB-28 flash gaff taped to the 6x6cm light mixing box of a Philips pcs2000 enlarger. 1/64th power on the flash gave a very good exposure.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
You will find continuous light preferable. Speedlights are the worst for output and color consistency, but even nice studio strobes have variability.
I produced some stop motion animation a while back with strobes, and the result was quite flickery. It wasn't a problem for that project, but for stitching it could result in patchiness.
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