Ask Me Help Desk - What setup do I need to take pictures of blueprints?

I am in the process of digitizing files onto the computer.
Blueprints and larger files do not fit in the scanner so I would like to create a setup where I could take high quality photos of the larger documents and convert them to .pdf (for example). The picture would need to be taken from directly on top of the drawing.

I need to be able to see all the details, so I need a really high quality and professional image.

Do you know what equipment and materials I would need to be able to do this (eg: camera megapixels, lighting? Reflectors? Tripod?).

All details would be much appreciated as I am trying to purchase all the equipment tomorrow.

Thanks and cheers.

Quote:

Originally Posted by Kev-Cali

I am in the process of digitizing files onto the computer.
Blueprints and larger files do not fit in the scanner so I would like to create a setup where I could take high quality photos of the larger documents and convert them to .pdf (for example). The picture would need to be taken from directly on top of the drawing.

I need to be able to see all the details, so I need a really high quality and professional image.

Do you know what equipment and materials I would need to be able to do this (eg: camera megapixels, lighting? reflectors? tripod?).

All details would be much appreciated as I am trying to purchase all the equipment tomorrow.

Thanks and cheers.

In order to know what type of camera you need, I need to know details of your scanner and scanned files. How big are your scanned files - in pixels (heightxwidth, e.g. 3300x2250) If you are scanning 8.5x11 pages at 300 dpi (3300x2250) you have 7.4 megapixels and most modern digital cameras (6-8 megapixels) will give you about the same resolution on an 8.5x11 file. If you are scanning at 600 dpi, then to get equivalent quality you would need a higher resolution camera, around 16 megapixels for an 8.5x11 file. Obviously, if you need this same resolution for a very large document, it will require many megapixels - much more than consumer-grade cameras provide! Your files will also be huge, consume a lot of disk space, and be slow to open and display on the computer. But, it is very likely you do not need that much resolution in the scan or digital image if you merely need to read the blueprint clearly.

In order to determine the setup needs, I also need to know how big the blueprints are. This determines if you can easily setup a tripod to shoot straight down, or if you need a slanted table to position the blueprint and then angle the camera down to match the slant of the table. Shooting straight down can also be complicated for setting up the camera (how do you look through the viewfinder to determine that everything is in focus and in the frame) so using an angled shooting table is usually easier.

Your tripod choice will be dependent on the shooting table or vertical shooting decision, and the weight of the camera. Depending on the camera's weight you may also need a tripod head as only cheap/lightweight tripods come with built-in heads.

You need 2 lights and light stands. Depending on the size of the blueprints you may wish to umbrellas or softboxes, rather than reflectors to help produce uniform light across the width of your blueprints. The critical thing is understanding the "angle of incidence" so that you position the lights correctly to avoid glare reflecting off the document and into the camera. I suggest you get the book Light, Science and Magic and read Chapter 4 "Surface Appearance" and understand the "family of angles" so you can determine how to properly place the lights.

You don't need strobes, hot-lights will suffice. However, there can be issues with hot lights creating, well, heat, which can make your studio uncomfortable, or even cause heating problems (or fires!) with softboxes, umbrellas, and the like. For this reason you may prefer to work with strobes. If you get strobes then you also need a way to trigger the strobes from your camera. You can NOT use the on-camera flash to light the blueprints or to trigger the strobes, as this will create bad reflections in your image.

Make sure you set the white balance on the camera correctly for the light you are using so that the blueprints come out the correct color, otherwise they may end up a very strange shade. (Scanners automatically configure the white balance of their scans for their own light but with a camera you need to do this manually as the camera has no knowledge of the type of light you are using. Auto-white balance is not very accurate.)

I'll give you some results of what I did recently:

Up to 11 x 17 drawings can be scanned locally for $0.08/page with a $2.00 minimum 1 bit. Not a bad price. Otherwise about $2.00 for a b&W 1 bit scan for larger drawings.

I had some actual 17 x 24 blueprints that I wanted scanned and went to Kinkos, Staples (just copy) and a CAD company.

The drawings were scanned at about $10 to scan and about $2.00 to print. They were scanned at 600 dpi, 8 bit grey TIFF and jpg. The files are big. 150 MB

I tried to take a pic with a 10 megapixel camera with poor results.

So (600 dpi * 17) * (600 * 24) that's 67.32 Mega dots.

A pixel is 1/72" of an inch.

Only with the drawing size and the desired resolution and the camera's capabilities can you determine what you need.

You can scan pieces of your drawing at various resolutions on a flat scanner to see what you need.

Conversion to vector was impossible with programs that the CAD place had. They suggested that they be re-drawn.

We basically determined that the .JPG format would be smaller and printable, but I asked for both. Didn't cost me extra.

Most people did't even know the resolution of their scanners. For instance they can tell it photo or grey scale, but you don't get shades of grey. It is still a 1 bit image.

They want to charge you to use their color scanning or color printer to print blueprints even if black and white except the CAD place.

Thank you for your responses.
I am by no means an expert in scanning or photography, I just know basics, lol. And unfortunately , I am in somewhat of a rush and need to purchase the equipment in the next 2 days.
We are currently scanning all of our b/w 8.5 x 11" files at 300dpi. For color photos I use the 24bit color option.
For this particular project that involves larger photos (lets say 12 x 18" color photo) that won't fit in the scanner, I need to get a scan-like quality image. However, for the blue prints (17 x 24" and larger) , I would only need the equivalent of the 300dpi b/w scan.
I just want to get a setup that would also allow me to be able to do the blue print pictures in the near future without going to Kinko's.
Sorry that I am unable to provide you with all the necessary technical specs as to what I need...
I was originally thinking that a 10-11 megapixel camera could be enough?
Would you recommend purchasing a slanted table and to shoot vertically? With a vertical tripod?
And if I understood correctly, I would need 2 lights (hot lights?) with 2 umbrellas?

Quote:

Originally Posted by Kev-Cali

Thank you for your responses.
I am by no means an expert in scanning or photography, I just know basics, lol. And unfortunately , I am in somewhat of a rush and need to purchase the equipment in the next 2 days.
We are currently scanning all of our b/w 8.5 x 11" files at 300dpi. For color photos I use the 24bit color option.
For this particular project that involves larger photos (lets say 12 x 18" color photo) that won't fit in the scanner, I need to get a scan-like quality image. However, for the blue prints (17 x 24" and larger) , I would only need the equivalent of the 300dpi b/w scan.
I just want to get a setup that would also allow me to be able to do the blue print pictures in the near future without going to Kinko's.
Sorry that I am unable to provide you with all the necessary technical specs as to what I need...
I was originally thinking that a 10-11 megapixel camera could be enough?
Would you recommend purchasing a slanted table and to shoot vertically? with a vertical tripod?
And if I understood correctly, I would need 2 lights (hot lights?) with 2 umbrellas?

For "photo quality" 300 dpi reproduction of a 17x24" image, you need more than 300 dpi which means more than 11 megapixels. But if you just need "working quality" then the 10-11 megapixel camera would be fine.

With a slanted table you shoot at an angle, not horizontally, not vertically. As an example, the table might go from floor level to 3 feet high, at a 45 degree angle. Then your camera can be placed at a 5-6 foot height on the tripod, and about 3-4 feet away from the center of the table. The camara would be angled 45 degrees down so the sensor of the camera is parallel to the shooting table, and aimed directly at the center of the shooting table so that you don't have any distortion in the image.

Hot lights are cheaper than strobes, but are more difficult to work with when you use diffusion materials (umbrellas, softboxes) because the heat can be dangerous near these materials.

Are you going to purchase this setup over the internet, or purchase it in-person at a camera store? Ideally you would go to a professional camera store where they can show you a variety of lighting options, and you can evaluate the cost and evenness of the light for each option.

Great Info! Thanks!
I will actually be needing a photo quality reproduction of the pictures. For the blueprints, working quality is fine. Are there any particular cameras that you would recommend?
Also, Are these shooting tables available at camera stores?
I intend to purchase the equipment at a local store in SF tomorrow or over the weekend and will figure out the lighting once there. I appreciate your suggestions.

Quote:

Originally Posted by Kev-Cali

Great Info! Thanks!
I will actually be needing a photo quality reproduction of the pictures. For the blueprints, working quality is fine. Are there any particular cameras that you would recommend?
Also, Are these shooting tables available at camera stores?
I intend to purchase the equipment at a local store in SF tomorrow or over the weekend and will figure out the lighting once there. I appreciate your suggestions.

I recommend you shop at Calumet in SF, and also at Keeble and Shuchatt in Palo Alto. K&S has a much better selection of lighting. There is also Gassers in SF but they are geared to professional photographers who know what they need and you won't get the advice and direction you need there.

The camera question is huge - it depends on so many different things - what else you might want to use the camera for, your photography experience, etc.

I can help you with this in-person - I'm in the SF area and shop at all of these locations. You can reach me at jcdill (dot) lists (at) gmail (dot) com