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5400owner
03-03-2005, 11:31 PM
Hello all,

I am the proud new owner of a Nikon Coolpix 5400. I am using the camera primarily for photographing rare documents for academic research.
I use the "S" mode, set at 1/30, F.28, saturation at black & white, and no flash (since flash burn can hurt the document and also tends to white out black text at times). All my photos are nice and crisp from the center until about 90% from the out edges, then everything gets blurry. I thought this might be a metering problem and tried all the different meters. I even tried the "Document Copy" scene mode to see if the camera's preset options would bring those edges into focus. No luck. Please help!

Ray Schnoor
03-04-2005, 06:15 AM
Hello all,

I am the proud new owner of a Nikon Coolpix 5400. I am using the camera primarily for photographing rare documents for academic research.
I use the "S" mode, set at 1/30, F.28, saturation at black & white, and no flash (since flash burn can hurt the document and also tends to white out black text at times). All my photos are nice and crisp from the center until about 90% from the out edges, then everything gets blurry. I thought this might be a metering problem and tried all the different meters. I even tried the "Document Copy" scene mode to see if the camera's preset options would bring those edges into focus. No luck. Please help!

Just to clarify, do you mean it is sharp until you get 90% away from the center(or about 10% away from the edge of the edge of photo)?

I haven't really noticed any softness around the edges of my Coolpix 5400 photos. One of the problems with photographing documents is to get the lens perfectly perpendicular to the document so that the entire document is in the same focal plane. You might try stopping the camera down a bit to increase the sharpness at the edges. As an alternative, you could try zooming out a bit to keep the edges of the document away from the edges of the photo. By just zooming out 10%, you would still have pretty good resolution of the document.

Ray.

dwig
03-04-2005, 07:34 AM
You're seeing the common results of when any lens, particularly a zoom lens, is used for macro at or near its widest apertures. You should abandon the "S" mode and use "A", setting the aperture relatively small (f/8-f/11). This will, of course, require the use of some support, copy stand or tripod, if you can't increase the lighting.

Given what I've seen in test reports on the 5400 and similar cameras, I would suspect that you will get the best results, for this type of work, if you use the camera at near its longest tele setting.

D70FAN
03-04-2005, 03:24 PM
Hello all,

I am the proud new owner of a Nikon Coolpix 5400. I am using the camera primarily for photographing rare documents for academic research.
I use the "S" mode, set at 1/30, F.28, saturation at black & white, and no flash (since flash burn can hurt the document and also tends to white out black text at times). All my photos are nice and crisp from the center until about 90% from the out edges, then everything gets blurry. I thought this might be a metering problem and tried all the different meters. I even tried the "Document Copy" scene mode to see if the camera's preset options would bring those edges into focus. No luck. Please help!

In using my 990 for document work I always worked in Macro mode. I would be willing to bet that this would help with your 5400 shots as well. Worth a try.

junkbokx
03-25-2005, 08:34 PM
I have been doing document photography for about 1.5 years now and I have the same problem as you. I currently use a Kodak D7630 6 megapixel camera that has a nice document setting. Although I am no photographer by any means, I believe the problem is something called spherical aberration in which light coming in is focused around the edges differently as in the center.

My solution is to raise the camera about 8-12 inches higher than one would normally place the camera and manually zoom the lens in to get as much of your document in the shot as possible (donít use digital zoom!). This does not correct the problem, but it does reduce it in my experience. I also focus on an area slightly larger than my document, as Ray Schnoor has already suggested. Yes, you will lose a couple of dozen dpi equivalents doing this, but that is better than having completely unreadable text in the corners.

The real root of this problem is likely the lens itself. Cheap point-and-shoot cameras do not have a sophisticated enough lens to get the level of sharpness required to scan all of the letters on an entire page of text. Consumer cameras usually make do with mass produced plastic lenses that work great for casual snapshots, but just try and find one that does a good job of getting a page number in focus all the way at the bottom left of the image.

For my next camera I wanted to get a Minolta Dimage A200, which not only has an economical 8 megapixel package, but offers a much better quality lens. Now I see that Canon has introduced the Rebel XT, an 8 megapixel d-SLR camera priced around $800 sans a lens. For the best possible document pics a SLR camera really makes a big difference. Again it is the lens that makes the difference. I have had occasion to use a Nikon D-70 (a 6 megapixel d-SLR) to photograph my documents, and the level of quality is an order of magnitude greater than with my Kodak. I was actually searching the web for information about macro lenses for the Rebel when I came accross this thread.

If you only photograph a limited number of documents I would suggest trying out page stitching (panoramic image creation). In my work I scan hundreds or thousands of pages at a sitting, and speed is of the essence, so stitching is a chore for me. You can zoom in on only a portion of the page (for example the edges), and then stitch the images into one of much higher resolution. This is great for archival quality images, or when you want high accuracy OCR. There is a program called autostitch ( http://www.autostitch.net/ ) that does a very good job, and is free. I have tried just about every stitcher out there, and this one works best for text documents in my opinion.

Just a tip if you donít already do this: use as much external lighting as feasibly possible. I use 3 desk lamps around my document area that provides light below the camera. Lighting above the camera will make a shadow on your document that doesnít really show up unless you process the images afterwards to make them bitonal or grayscale. Donít use fluorescents as they actually flicker from off to on faster than the eye can see, but the camera will eventually capture it while darkened. A flash is, as you know, unacceptable because the light does not have enough time to diffuse. The optical properties of the paper you image also plays a big role. Modern paper (like in a magazine) tends to be very reflective, but old documents donít reflect much light. You can diffuse the light of the camera flash by either taping several layers of semi-transparent milk jug plastic in front of the flash, or by using aluminum foil to reflect the flash backwards and then bounce it back with a white sheet. You can also raise the white balance setting on your camera a little bit.