camera settings for photographing detail pencil drawings

[eggbertfrazzle]

Hi i was wondering if you guys could help me, my task at work is to begin to archive a load of very important architectural drawings. Most of these drawings are pencil sketches onto paper no bigger than A1. However some of these drawings are very light and cannot be clearly seen and some maybe very detailed. My job is to make a digital archive of these drawings and develop a cataloging system for them.

We are about to buy a high resolution scanner to scan to most important drawings however for now we just need reference images of each drawing for the catalogue and hence have decided to use a camera along with a tripod mounting next to some sufficient lights.

I use a Nikon d100 and have finally setup the tripod and camera to line up with an A1 page. My question to you guys is what format should i begin to save these images as, jpegs, raw, tiff etc.

Also as some of these drawings are very fragile some post production may be needed to darken the lines via photoshop.

 

[eggbertfrazzle]

test

 

[Dwig]

You should shoot RAW and after PP you should save in TIFF for the archive.

You are probably going to find that the D100 doesn't have adequate resolution to do this job well. at least if you are planning on shooting the copies as single images. With only a 6mp sensor (~2000x3000px) and an A1 original (594 × 841mm) the finest line that will be well resolved will be about 0.6-1.0mm, which is a rather heavy pencil line. Each individual pixel will cover only about 0.3-0.4mm of the original.

To resolve fine pencil lines on an A1 original you need something more in the line of 24mp. You could achieve this type of resolution with the D100 by using a very high end lens with very low distortion (e.g. Micro-Nikkor 60mm f/2.8, Micro-Nikkor 55mm f/2.8, Micro-Nikkor 105 f/2.8, ...) and making 4 images of the original, one of each quadrant. You would then need to stitch the four images together. If the lens used for copying has any barrel or pincushion distortion you will find the stitching to be all but impossible.

 

[eggbertfrazzle]

thank you for your reply Digg,

I am currently using a Sigma 20-40mmD lense, do you think it is sufficient?
also i have created a sort of mini photobooth, with two spot lights facing the drawings at equal angles on a white base.

Do you recommend any other specific camera settings i should implement?

Also if some of the drawings don't need any PP do i save the archive drawings as TIFF also?

What are the benefits of saving in TIFF for he archive as appose to a RAW file?

Thank you in advance

 

[degro]

thank you for your reply Digg,

I am currently using a Sigma 20-40mmD lense, do you think it is sufficient?
also i have created a sort of mini photobooth, with two spot lights facing the drawings at equal angles on a white base.

Do you recommend any other specific camera settings i should implement?

Also if some of the drawings don't need any PP do i save the archive drawings as TIFF also?

What are the benefits of saving in TIFF for he archive as appose to a RAW file?

Thank you in advance

RAW files are camera dependened. TiFF is not. In other words a photoshop might not recognises the raw file in the future and tiff will. Also you can view TiFF in windows explorer without the need for a plugin. Also a good possibility is to convert the raw files to DNG that is also a platform free fileformat.

 

[epatsellis]

Typically, this type of work is done with a view camera, a process or very high quality enlarging lens and scanback. Take a look at betterlights website to get some idea of what kind of a hornet's nest you've walked into. Read some of their technical papers and look at some of the case studies.

I would seriously reconsider the high resolution scanner approach, in favor of the scanback approach. There's a reason why nearly every museum, archeological survey, library and even the Library of Congress uses a scanback.

 

[Dwig]

...
Also if some of the drawings don't need any PP do i save the archive drawings as TIFF also?...

RAW files can't be viewed, displayed, or printed without doing some form of post processing. They are useless for any purpose other than for post processing to create images that can then be put to use. Archiving the RAW files would mean that the only people that could make use of the archive would be those with the proper software and skill set to post process the RAW files into a usable bitmap format. Even searching through the archive would require specific software that can read the particular RAW flavor used.

TIFF is the universally accepted bitmap format for high quality image archives. It allows you to avoid the image quality loss associated with lossy file compression, such as that used by JPEG, while being as universally readable.

BTW, the Sigma 20-40 lens might well be adequate for single images, it will have way too much rectilinear distortion to do really good work. It would be all but impossible to do good stitching using images made with it. The necessary distortion correction would compound the limited resolution problems resulting from the camera's 6mp image files.

 

[zigzaggzoom]

I think you should make two changes in there to improve the image quality. Basically you should buy the best quality scanner and you can tell the painter to draw with the best quality pencil so the effect would be great.

 

[kkamin]

I'm not an expert, but it seems like it would be easiest to scan everything in. In PS, all you need to do to darken the lines is duplicate the layer (command+J) and put the new layer in 'multiply' mode--you can then adjust the effect by lower the layer's opacity. <edit: but if these are colored blue prints, you might have to approach it in a different way through selection techniques, curves adjustment, masking, etc. to get the same result. Idk though, you could post a sample in the Post Processing section and have others help you figure it out.> If you were to photograph everything correctly, it is a lot of added hassle in my opinion (copywork can be very complicated with a lot of gotchas).

Here are some links for file management:
Catalog Software Basics | dpBestflow

Quick Reference | dpBestflow

I think a larger issue of your new job is creating a sustainable way to catalog and preserve these files. Some museums have useless catalogs now and are needing to redo everything, because the system they used is no longer supported. Archived files will eventually become corrupt down the road, and you'll need a way to test for that and have much redundancy, and a way to maintenance that. I'm not an expert but I am in a similar process right now for my own business and I didn't realize the can of worms or concerns I was opening. Good luck!

 

[epatsellis]

...I think a larger issue of your new job is creating a sustainable way to catalog and preserve these files. Some museums have useless catalogs now and are needing to redo everything, because the system they used is no longer supported. Archived files will eventually become corrupt down the road, and you'll need a way to test for that and have much redundancy, and a way to maintenance that. I'm not an expert but I am in a similar process right now for my own business and I didn't realize the can of worms or concerns I was opening. Good luck!

Can you provide references for this statement? My work and with historical societies and museums says differently, if that is the case, I'd like to know.


I still contend that your capture medium, scanner or camera is the limiting factor, either too small of a capture (and Bayer pattern interpolation) in the case of the camera, or poor tonal reproduction without significant operator involvement (and a non calibrated, likely inaccurate color response) with the scanner.
For reference, see: The Khabouris Codex Reproduction Project for a dicussion on shooting papyrus texts, and Better Light ...The Best Device for Art Reproduction Imaging for general art repro info.

erie patsellis

 

[kkamin]

Can you provide references for this statement? My work and with historical societies and museums says differently, if that is the case, I'd like to know.

I listed some links before the statement that does into detail on digital asset management issues. It sounds like the project is big for the company but it isn't epic where they are going to hand over the digital files to a company for preservation. He will probably have to devise a system where he is storing the cataloged files in several redundant ways (RAID type system, read once media, remote server) and has a system to check on the files health from time to time and address file corruption--hard drives and dvd's are not archival. They are not film negatives preserved in glass in a fire proof climate controlled vault. Corruption will eventually make its ways into the files; dvds die, HD sectors go bad. So to be able to identify when this is occuring and being able to make a new disc or replace a HD is critical.

Just 12 years ago many people and museums were using Kodak Photo CD technology to create digital archives of their work.
kodak

Compared to today, little was known about those processes. It is now obsolete and I forgot which museum, but a big one, is having to go back into their collection and re-archive everything. This was only 12 years ago. I'm not saying a .TIFF file will be obsolete in 12 years--it'll be good for a long time I'm sure, but eventually something will replace it. .DNG is building steam but who knows what will happen to it and if it will survive in 12 years, something more inspired might come around.

I am placing my eggs in the dpBestflow basket. Those were the initial links I posted in my first post in this thread. It is an ASMP initiative funded by the US Library of Congress. There are not software specific (they do use examples of different ones) but rather outline principals in great detail in order to preserve digital information and a digital workflow for commercial photographers.

I think the scan back is a great idea and know museums having been using them for sometime to do their copy work. But it might be overkill for an architectural firm just wishing to convert their paper blueprints to a digital format. And he or she would have the have color calibration issues as well working with a camera.

To the OP. For the time being, you can get something called a 'copy stand' which is designed for doing this type of work. It insures you wont have keystoning by having the camera on a fixed plane. And the ones I've used have lights mounted on them to light the copy area evenly. If you end up trying to hang these on the wall and light them that way, it can be quite an exercise in patience.

Good luck.

 

[epatsellis]

If these are important and are truly in need of archiving, I would use whatever digital means, and shoot archivally processed 4x5 or 5x7 film negatives as well.

It's a lot of work, I know, I'm presently working on a pro bono (mat'l cost only) project involving archiving some 2,000 8x10 glass negatives, and close to 1,000 5x7 nitrocellulose based negatives. But in order to qualify for a matching funds grant, they have to be archived to industry accepted archival standards, which in the eyes of conservators means film dupes, no digital file is considered suitably archival.