Equipment to Photograph Blueprints

[ctindall]

First, please forgive my ignorance... I know nothing about photography.

I would like to build a table for photographing large format blueprints (up to 48"x36"). I envision that this would consist of a digital camera attached to an adjustable support above the table. Through trial and error, we would determine the proper camera height for different sizes of paper.

This is not going to be used for production photography. I am an engineer and I need an effective and inexpensive method for sending my red lined construction drawings to another office. Wide format color scanners are WAY too expensive.

If a device is available for this application I'd sure like to know. Any tips would be appreciated. Feel free to send me an email: chris (at) tindall (dot) pro

[Ralph Barker]

Although what you describe is a large version of a typical copy stand, I think you need to define a few more parameters, Chris. Note, too, that this is a large format photography forum, so, within that context, most of us would approach the problem using 4x5 or larger film in a view camera.

The first question I'd have is how the remote office is going to use whatever you produce? Will they just be viewing the annotations, already having a copy of the blueprints? Will they need to add further comments of their own? Will they need to print the result to scale? Any to-scale reproduction would get rather involved using a typical digital camera.

How are the drawings created in the first place? If they are created from a computer-based design/drafting program, you might be better off looking into annotating the original files - assuming you and the other offices also have the same software.

[JW Dewdney]

forget it! The equipment you'd need to get the infomation you need on there would be about the same as an Océ large format copier/scanner ($50K plus!) - the best and cheapest way is to send them to an engineering copy firm for scanning. Trust me. I know.

[photographs42]

I would forget about the copy stand concept. Of course it would work, but you don’t need to go to all that trouble. Get a decent Digital SLR and one lens (they usually come with one). Get a tripod, two light stands and two lights. The lights can be about anything but something directional is best (they could be flash units but continuous lighting is easier to work with). Pin the prints to a wall and place the lights to each side at about 45 degrees to the print.

Point the camera at the center of the print, put it in automatic mode and make the picture. If you have a space to dedicate to this just leave it set up. If not, find a way to mark the floor so you don’t have to experiment each time.

Jerome

[JW Dewdney]

Let me spell it out a bit:

Problem One:
The only problem with this is that you need a MINIMUM of 6 000-12 000 pixels to resolve the details of E size drawings. Most engineering copy places will be able to provide a 1-bit tiff file at this resolution. The only way to get a readable drawing is to use a digital scanning back, such as a better light, etc... not cheap.

Problem Two:
SOME people (i.e. architects) receiving the file will trace over it on computer to generate working drawings. There's going to be a lawsuit for someone, somewhere down the line if there's any uncorrected distortion (i.e. barrel, pincushion) as there are with ALL lenses, to some extent. The only way around this is to use photogrammetry - you'd have to purchase a very expensive system with dedicated software for that SPECIFIC camera and lens, that corrects for distortions in the glass, and in the film or sensor plane.

Problem Three:
Your copy setup. It's all well and good to use lights against a wall, but your 'workflow' is going to be MUCH easier if the lighting is PERFECTLY even (within 1/4 stop) which is EXTREMELY difficult to do - and is going to take a long time to get just so. Therefore you'd have to dedicate at least 100 sqare feet to your copy setup. You get the idea.

There are definitely other issues having to do with the amount of time it takes to properly prep the files to give to a client - but I won't get into it here.

[Louie Powell]

I'm also an engineer. And to me there are two practical solutions to this problem.

One is to adopt Ralph's suggestion - install a copy of AutoCad on your laptop, and annotate the original digital files. I seem to recall that there is a scaled-down version of AutoCad that allows you to annotate existing drawings but not create new drawings that is designed specifically for this purpose.

If the drawings are hand drawn (unlikely - this is the 21st century), or if there is some other obstacle to digital annotation, then the fallback solution is to have a duplicate set of prints prepared, and then transfer the annotations to it as an office copy. Send the originals back via FedEx. Actually, transferring annotations to the backup set of drawings is one of the traditional assignments given to the youngest engineer in the office.

[jnantz]

chris

from time to time i photograph blueprints...

what i do is get 2 piece of foam core and tape them together.
then i spread the blueprints onto the board and hang it vertically.
i shoot it straight on, light it evenly and have no problems.

while i use a 4x5 camera to do it, you could easily use a different
type of camera in the end ...

good luck
john

[photographs42]

Chris,
I made some assumptions in my earlier post. I assumed that the other party already has a copy of the blueprint and all they need is the red line mark-ups. I also assumed they are not really “blueprints” but are blue line or black line prints. If they are blue line or black line, the red marks should show up clearly enough using my method.

You don’t tell us where you are but if you are in a town large enough to have a decent camera store, go there with one of your marked up prints and ask them to demonstrate a 6MP camera by taking a snapshot of your print. Have them set the camera to jpeg mode. Don’t worry about lighting, just hold it up and snap. If you have a laptop, take it and transfer the picture to your laptop. From there you can see if the image will do what you want.

It may turn out that you don’t even need the lights depending on the lighting in your office. You don’t need extremely even lighting for your purpose but you can’t have glare. You really don’t need the tripod except the tripod will insure a stable camera (no blur).

If my assumptions are correct, others here are making this far more involved than it needs to be. If I am wrong about my assumptions, please let me know.

Jerome

[andy bessette]

Chris,


..if you are in a town large enough to have a decent camera store, go there with one of your marked up prints and ask them to demonstrate a 6MP camera by taking a snapshot of your print. Have them set the camera to jpeg mode. Don’t worry about lighting, just hold it up and snap. If you have a laptop, take it and transfer the picture to your laptop. From there you can see if the image will do what you want.

It may turn out that you don’t even need the lights depending on the lighting in your office. You don’t need extremely even lighting for your purpose but you can’t have glare. You really don’t need the tripod except the tripod will insure a stable camera (no blur).

If my assumptions are correct, others here are making this far more involved than it needs to be. If I am wrong about my assumptions, please let me know.

Jerome

Yo Jerome,

I agree about there being no need to complicate this, and I for one don't think you are wrong. But for the tripod.

An inexpensive tripod will allow as long a shutter speed as is required by the ambient lighting. And a simple test can determine the proper setup. All one needs is a wall and a tripod-mounted camera. If required, the biggest lighting expense should be a clip-on worklight with daylight fluorescent bulb.

best, andy

THERE'S MORE TO OPTICS THAN MEETS THE EYE

[JW Dewdney]

Being an architect who frequently gets digital files of original drawings - I would expect the drawings to be accurate enough to trace over and build from. I will personally do this if I have no other reference. It's EXTREMELY common in the industry. I really have no idea what anyone would want with files that weren't dimensionally accurate or contained distortions. But that's me - and MY assumptions. I just figure that if you release a file to someone, that you have the responsibility to ensure that the file is useful for even the most demanding of applications.

But I suppose - as long as they are ONLY for indicating the redlined AREAS - and not to dimension from... that pretty much anything would work, including an $80 digital camera.

[photographs42]

Being an architect who frequently gets digital files of original drawings - I would expect the drawings to be accurate enough to trace over and build from. I will personally do this if I have no other reference. It's EXTREMELY common in the industry. I really have no idea what anyone would want with files that weren't dimensionally accurate or contained distortions. But that's me - and MY assumptions. I just figure that if you release a file to someone, that you have the responsibility to ensure that the file is useful for even the most demanding of applications.

But I suppose - as long as they are ONLY for indicating the redlined AREAS - and not to dimension from... that pretty much anything would work, including an $80 digital camera.

JW,
I don’t know what happened to Chris! Remember him, the guy who started this thread.

Anyway, I am also an Architect and if someone sends me drawings to be traced I also want them accurate. But Chris indicated that he wanted to pass on his red marks to other people, and that only makes since if the other people already have the drawings being red marked.

Jerome :)