Need to photograph large maps and drawings - Where should I start?

I'd like to get digital images of some old maps and drawings (both

color and b/w that range in size from 18"x24" to 30"x40") before

they fall apart. The problem is that these old drawings are very

useful but we are afraid to handle them. We found that preserving

them is very expensive and we'd get more benefit from these maps if

they were digital.

 

Please tell me what I should consider purchasing if it is possible

to capture images from say a Nikon D70 and a mounting table.

 

What table and lights and lense? Also will I need to correct the

images (rubbersheet)? Thanks!

30 by 40 inches from a D70?

 

Maybe you need a medium format camera, a good lens, and some Tech-Pan.

 

Cheers.

You could either put the map on the wall and photograph it or use a table. I'm thinking what you are trying to achieve is similar to copy work, right? Well, if that's the case set up your lighting similar to how you would find it on a copy stand. But since 30x40 is pretty big, I suggest you hang the map on the wall and set up lights on stands. What you need to do is light up the area with even lighting. You might be able to get away with using 2 lights. Place each at 45 degrees from the center of the map so you won't get light bouncing off the map and directly hitting the map. This will cause hot spots. Pull the light back until the lights evenly light up the map. Shoot and check image to see if you need two more lights. If so, place two on each side. One low and one high. Also, are you planning to eventually blow these up to 30x40? If so, I will suggest you forget about the D70 and go with a medium format or a 4x5. Hope that helps.

It all depends on how much detail that you want to preserve.

 

A D-70 is probably not going to be in the ball park.

 

Get a cup of coffee, get comfortable and go here:

 

http://www.library.cornell.edu/preservation/tutorial/conversion/conversion-04.html

 

and here:

 

http://www.dlib.org/dlib/october96/cornell/10chapman.html

 

and here:

 

http://www.mnhs.org/about/publications/techtalk/TechTalkJuly1998.pdf

Lets say that 30x40" map is .9x1.2 inches on the 35mm film. This is a 33.3 to 1 ratio. If you could get 50 line pairs/mm on the film; with a perfect setup; this would mean say 1.5 mm on the map as barely resolved; say 3mm lettering with some almost no safety margin; with a best case system. With old E size drawings that were photographed on 35mm non sprocketed film for aperture cards; many time specs required 1/8inch type say 3mm. This is with super high res B&W microfile film; and say a 1.15 x1.53 inch dimension on the microfilm for the 30x40" map. This is only about a 26:1 ratio. No matter what lens and film; there is a limit; and 35mm will not resolve very small type; lines; features of a 30x40" map. In copy camera work the smallest camera we would use to shoot a 30x40" map would be a 5x7 negative; for a process camera; a 8x12" lith negative. <BR><BR>Here I use a 35Mpixel scan back on a 4x5 camera; or a 4x5 trany or a 6x9 trany; and a drum scan; or a flatbed if good enough. A map that is good enough to go thru a color might be scanned at 300 to 400 dpi over a 36" width; thus the 30x40 colr map would be a 30x40 RGB image; at 300ppi; this is a 309Meg image; 549 megs at a 400 ppi 30x40 image. The files can be huge.

A smaller 18x24 image can be scanned as four panels; with a regular 11x17 flatbed; and then recombined together. You need a box with alot of ram. This can work well if you do some experimenting. I have used this for about a decade; and manually reconnected them together. Flatbeds do have illumination falloff; so allow decent overlap. This is alot of labor. When 200Mhz was state of teh art; I had a server with NT and 1 Gig of ram with photoshop; to do these jig saw puzzle projects. Today they are dedicated 36" wide flat scanners at service bureaus; soe even will scan a mounted map.

Hi Adam -

 

I would try to find a amateur LF photographer in your area. Have them shoot the maps (on an evenly illuminated wall) with a 8x10 camera and color reversal film. This can then be professionally scanned (for an archive file) and printed for other purposes.

 

Good luck.

Adam; you also can check the larger city service bureau print shops in your area; that may have a scanner or camera dedicated to shooting artwork. This has been done digitally with scan backs for now a decade.

The end usage needs to be thought out. Some museums and government contracts want an actual 4x5 trany; and a drum scan; with color references; grey scale references; and a steel rule scale on the borders. The intersting thing is that formal government specs for scanning are in written dpi specs; not ppi. Other folks may just a portfolio of their artwork or maps; for a show; to submit to a book publisher; etc. A "drawing" can be a hand drawn in ink on Linen; on vellum; on paper; a blueprint' a blueline; a giant Xerox/Bond copy; a bum wad/onion skin hard sketch; a pen and ink redendering. These can be just a bitmap or a greyscale image if shaded. Maps can be in B&W; in color; combinations of aerial and CAD grid lines. "maps and drawings" could be several hundreds of different types.

>>these old drawings are very useful but we are afraid to handle them<<

 

From what you are saying I take it the issue is more a practical one than an artistic one. In that case, just get the clearest image you can using whatever DSRL you have. The D70 with a standard lens (50mm) will do fine. Make sure the light is uniform and no hot spots fall within the maps/drawing. Then, you can make prints and handle those instead of the originals.

 

However, *if* the originals are of any value to you (financial or sentimental) you will still have to solve the preservation issue, which would be best discussed with an expert in that field.

Not a problem. If, after reading the excellent advice already posted, which may be best concentration of good advice on a tough subject that I have seen in a while, you wish to shoot with a D70, here's how.

 

Shoot the maps as panoramas, using as many pieces as need to get the detail you want. At 300dpi, a 30x40 is 9000x12000 pixels. that is a grid of 3x6 landscape frames, plus 1/3 overlap for stitching gives you 4x8 frames. If you need more detail, shoot more frames of smaller areas.

 

If you shoot very small areas, you may have to flatten the maps with glass or use a vacuum frame. Amateur frame=cardboard box, replace one wall, or part thereof, with pegboard; tape over flaps and other air infiltration places; insert vacuum hose through hole in another wall; use low vacuum.

 

Macro lenses are corrected for both close focusing and for a flat field. Try different focal lengths with your existing lenses, taking these factors into consideration:

Enough distance to stay out of the way of your lights;

Long enough to avoid light fall-off typical with many wide angles, so you do not get light-dark-light-dark across the final print.

 

You will probably find it much easier to shoot the maps if you can safely mount them to wall. Getting centered and oriented correctly above a big map on a table is a big task. Most process cameras and large-scale copying is done with horizontal camera mounted on tracks. That way the shooter can walk around to touch up things, not climb up and down a ladder or need assistants. It also gives you the distance needed for longer focal lengths.

 

Being able to pivot the camera around what is called the lens nodal point increases quality by eliminating parallax errors. To do that, you need to mount the camera so that you can move the camera backward on your tripod head. Typically, you would use a slider rail or calibrated focusing rail. If you look up this panorama topic here and on various sites, you will get a lot of info, including the nodal point distance for your particular lens. You can also forget the nodal point and see if you like what you get. The better the repro quality you want, the more important the technique.

 

Unlike going at prints with razor blades, with digital the stitching software does the toughest work.

 

If the maps are of some historical value, you may be able to obtain assistance from local museums, historical societies, or universities.

 

Forgive the scantiness of the reply, in spite of its length, but panorama is a big topic.

 

This may be too much trouble, but if you want to shoot big maps with a D70, this is how,

 

Bill

I'll agree with Bill here - stitched pictures from a DSLR will probably get you the best price/result ratio. You'll probably want a good macro lens (typically because those have a reasonably flat field and reasonably low distortion at those distances). Stop down to an "effective" aperture between f/8 and f/11.

 

As for the lights, I'll guess that flashes are less likely to cause problem than continuous lights (flashes generate less heat). If future preservation of the maps is important, it probably makes sense to use flashes that have a lower UV emission. I'd guess that a pair of studio flashes with large umbrellas of softboxes would probably be best.

 

Shoot raw files with a lot of overlap - those'll help you get the best possible quality.

 

Shoot a pair of test targets (one with a grid, one pure white) along with each (entire) map, they will potentially help you map the lens distortion and falloff better.

 

Summarizing, the idea is to get the raw data in a digital form. Putting the bits back into an image can actually wait.

 

If there's any risk of any kind of perspective distortion, put a marked "frame" flat on the map as you shoot, such that the frame ends up at the edge of each shot. Correcting perspective for the frame will be easy, and will give you perspective correction for the entire shot, including the "active area".

 

The alternative, like someone said, is to have a large format camera with a lens optimized for those distances (there are macro lenses), and to shoot on a single piece of LF film.

get it scanned at a blueprinter's for god's sake. It'll cost you all of $40

MAYBE. Probably less.

Yeah, Jean-Baptiste Queru. If you shoot a control grid the size of the frame you decide upon, you can correct distortions for that, apply the same corrections to each frame, and then stitch. Distortion can include uneven lighting, although testing should allow you to remedy that beforehand. That is so cool.

 

There is better and worse graph paper. Get engineering-quality paper. If you print your own from the many templates online, measure the printout carefully to be sure the template and your printer give you excellent results. Just a little bit of distortion, repeated several times, will give you a wavy look, like looking through a piece of cheap glass.

 

Bill

Here is one way to get the best of what you got. Like other said, you may have to scan it for best result.

 

Put the DSLR on a L-plate. Rotate it 90 degree. Put the L-plate on a shift plate. Take two shot with the shift plate and merge it. With a 3:2 canon 20D, two merged shot like this will yield 22.5 x 30mm effective sensor size. At this sensor size, you will need 34X magnification to get to 40 inches. If you use a 50mm macro lens and manual focus, you should be able to get some contrast at 68 lp/mm if you stop it down to F11 or so. At 34X, you will end up with around 2 line pair (or 4 dots) per mm. AAA map has 1mm pitch font. You won't able to read 1mm line pitch fonts. 2mm line pitch font should be OK.

 

You may need to do 2x2 (4 frame) stitch if you want to read 1mm pitch font. Good Luck.

This thread is like wanting to make your own flour; bolts; paper; shoes; grow you own watermelons in New York City; Growing corn in a shut garage in ames Iowa with grow lights; making ones own soaps with potash and lye and fats. Alot can be fun and a way to learn; but folks do this type pf work all the time; for radically less in coast than a fun experiment.<BR><Br>a fine map with engraved hatchings can require a 400 ppi image at full size. Thus that D70 will give a whooping 7.5 x5 inch image at 400ppi; and require 32 panels; ie 30x40/7.5x5... Probably about 50 panels with a tad of overlap. <BR><BR>The bluprinet comment is abit funny; here I run 5 blueline machines.

With a 36" color scanner; one just sets the computer to say 300 or 400 ppi; and feeds the original in; and then a giant file is created. There is no camera.

A once common 11x17 "300dpi" flatbed can be used to scan several sections; and then fit them together. This was common 5 to 10 years ago. It is usually radically quicker then messing with a digital camera; theat has way less resolution.

Please just take it to the blueprinter's like I said... usually there are many

reprographic places in a decent sized city. Anywhere there's an engineer.

They can scan 48" by any length usually. This way - it's their risk handling

the documents also. You are guaranteed dimensional accuracy and don't

have to mess with a new process this way. I have it done all the time for

architectural drawings. Just trust me on this - you can write me directly if

you need more info.

I concur with Jonathan Dewdney and Kelly about the blueprints. I worked with thousands of very old Architectural drawings before they were transfered to the digital world. Sometimes having the originals is better too, I have the original architects drawings of some very old buildings in London, they look great framed. I imagine if I were an architect looking for a drawing it would be easier via the computer than via the archived file rooms I once got lost in!

 

Cheers.

On a Wall with a true copy camera or at least a 4x5 and then drum scan them.

I doubt if drawings and maps have enough detail to require drum scans of 4x5! An Epson 2450 or newer, plus any printer capable of producing 30" wide stuff, will make a reproduction as good or better looking than the original. A 4x5 camera will do more than an adequate job of recording them. Scan for a 300dpi image (at 30"x40") and could probably have the color depth reduced to trim the filesize. Then make prints to work from.

 

You could do this just as well, I'm sure, with medium format equipment, but 4x5 is cheaper.

Thanks for all of the advise. Our local blueprinter is more concerned with production and would not think twice about tearing or damaging an original in a sheet feed slit scanner. It appears that tiling might be the answer. Does anyone recommend a stable camera mount (for a DSLR) like is used in an enlarging system?

 

Thanks again!

Before you invest on the equipemnt, you may want to take a few test shot to make sure the nikon D70 can give you the look you want. For your reference, I took a quick 4x4 stitch of a 36"x24" AAA Map. Here is how a 500x500 section 100% crop look. Shot with a Canon 6MP 300D with a 50mm Pentacon f1.8 at F11. 4x4 stitch with post stitched size = 5635x3754. Depending on your resolution need, look like you may need more than a 4by4 stitch. Hope it help.

 

<img src="http://d6d2h4gfvy8t8.cloudfront.net/3402077-lg.jpg">

Adam:

 

Listen to Jonathan - You will save a lot of time and money to simply go to a blueprint/architect/civil engineering printing company and the quality will be superior to anything you do digitally regardless of what others may say.

 

They can sandwich the maps/drawings & protect them while providing a direct repro

 

Good Luck