4x5 format pieced together panorama questionsgreenspun.com : LUSENET : Large format photography : One Thread
I have become interested in making panoramic images out of "pieced together" 4X5 format images. I really like the exploration of space that this affords. Having never tried it, I have a few questions about basics that you may be able to help me with so that I don't have to recreate the wheel... (I will be using a 150mm lens)
1. On an evenly lit scene I can see that just one exposure measurement will work, but what about a long horizontal scene where the lighting changes across the scene? Should I just be taking an icident measurement for each segment or should I use some other technique?
2. What's the best way to think about enlarger exposure for each of the segments so that the pieced together image looks smooth all across its length?
3. How much of the field of view of my lens should I use (all/part) to achieve good flow across the scene without too much distortion?
4. Is there anything good written out there on the technical aspects of this type of project?
Thanks in advance for any help with this new adventure.....
-- Scott Jones (email@example.com), October 12, 2001
I have not done much of the type of work you are asking about but hopefully you are using a camera which will let you shift the film standard and not just the lens standard. Rear shifts will prevent strange ange near/ far relationship perspective shifts.
As far as exposure goes, I'd bracket on the suspect frames makinbg one exposure for the highlights and another for the shadow portion. if you are using digital output for the final montaged panoramic there are ways in Adobe Photoshop to drop in better shadow details into the more overall well lit portions so the effect looks more as the human eye would perceive the scene.
-- Ellis Vener Photography (firstname.lastname@example.org), October 12, 2001.
View Camera's Platinum issue like 6 mos, or a year ago has a nice story of a guy who does triptychs -- He says to not bother trying to make them fit as they won't. The triptychs I've done never fit anyhow, so I like his idea of letting your mind sew them together rather than looking for the problems. Though a triptych and a panorama are different I suppose. Dean
-- Dean Lastoria (email@example.com), October 12, 2001.
Scott, I'm just about to get my feet wet in LF but let me throw in my two cents (and worth much less) on questions (1) and (2):
Finally, http://www.panoramas.de/panoramas/html2e/index.htm has some good hints on finding your lens' nodal point around which you want to pivot the camera.
- I would use the same exposure (Zone III for important dark areas, etc.) for all negatives in the panorama. This simplifies printing exposure and ensures that scene tones will combine seamlessly. However, this will rule out scenes with values greater than 5 stops unless you can precisely dial the correct N- or N+ development for each neg.
- Related to (1) above, I would start with the minimum exposure time to get maximum print black (MEMB), derived from printing a blank negative, to print all the negatives in the panorama.
-- Bong Munoz (firstname.lastname@example.org), October 12, 2001.
Take a look at the following link:
-- Dave Willison (email@example.com), October 12, 2001.
I meter the whole scene as if it were one frame and shoot all the images at the same exposure, then correct locally in the darkroom to the extent that it is possible, otherwise the images won't have a consistent texture and the edges won't match. Also, if you are taking time to adjust the exposure between frames, you will have more problems with clouds and other elements in the picture moving.
-- David Goldfarb (firstname.lastname@example.org), October 12, 2001.
Scot, are you trying to stitch the images together for a seamless Pan, or are you looking for a piece by piece effect. there is a very big difference...
-- Bill Glickman (email@example.com), October 15, 2001.
You're going to have difficulty making the individual images line up.
Think about all you see projected on a sphere like in a planetarium or an Omnimax theater, with your lens nodal point at the center. Note that your film is a flat plane. Basically, the sphere is projected onto the plane. When you rotate the camera, even being careful to rotate around the nodal point, the overlapping areas are not going to map to the plane identically, and therefore, you can't lay the flat images side-by-side and have them line up.
The answer to question #3 is, to get perfect alignment, you can only use an infinitesimally thin vertical line down the center of your image. That is not a very encouraging answer, since you'll need an infinite number of images. However...
If you digitize the images, you can merge them in a computer using merging software. These programs effectively project the images back onto the sphere (or cylinder) and merge them there, and then project them back onto a longer, flat plane. Most of the instructions I've seen suggest 30-50% overlap between images.
One of the most useful sites I've found is Panoguide. They include reviews of available software.
The one piece of software that is free and easy to use is Pixmaker Lite. It may be limiting for more sophisticated projects, but is something that is very easy to learn to use when starting with panoramas.
-- John H. Henderson (firstname.lastname@example.org), October 16, 2001.