Frequently Asked Questions

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How can I get a question answered?

Hundreds of questions about NIH Image have been asked and answered on the NIH Image mailing list, which is subscribed to by over 1000 NIH Image users. You can see if your question has come up on the list by doing a keyword search of the list archives at:

gopher://gopher.soils.umn.edu
Note: you can narrow searches by combining keywords using AND.

You can also browse the monthly list archives at:

http://www.soils.agri.umn.edu/infoserv/lists/nih-image/archives/
If you can't get an answer by searching the archives, try posting a message to the list (you must be subscribed) at the address:
nih-image@soils.umn.edu
Your message will be routed to each and every person on the list. You should, therefore, consider the nature of your post and by all means do not send email subscription requests to this address.

How do I (un)subscribe to the NIH Image mailing list?

The NIH Image mailing list is a forum to post and answer questions concerning NIH Image and its use. There are over a thousand subscribers to the list. Subscription and all mail routing is done via a listproc server at the University of Minnesota. Subscribe to the NIH Image mailing list by sending a message containing the line:

subscribe nih-image [your real name]
Note: substitute subscribe or unsubscribe as appropriate Send this message to listproc@soils.umn.edu There is a separate email address (nih-image@soils.umn.edu) for posting your question or answer regarding NIH Image.

I don't want a ton of email but I want to subscribe, how?

You can set your subscription to "digest" mode, which collects all the daily messages (sometimes there will be very many) and sends it out once per day. Send an email message to listproc@soils.umn.edu with the command:

set nih-image mail digest
To reset your subscription to "trickle", or many mailings mode send:
set nih-image mail ack

Does NIH Image run on a PC?

Scion Corporation is porting NIH Image to Windows 95. See the "What's New?" section of the NIH Image home page for more information. NIH Image also runs under DOS, Linux, or NextStep using the Executor Mac emulator from Ardi (http://www.ardi.com).

Is there a UNIX version of NIH Image?

NIH Image has not been ported to UNIX but it runs on SUN and HP workstations using Apple's Mac emulator for UNIX called Macintosh Application Environment (MAE). Information about MAE is available from "http://www.mae.apple.com".

My Mac has 128MB of RAM but the NIH Image About Box shows only 2500K free. Why is that?

You need to allocate more memory to NIH Image. Click (once) on the NIH Image icon (a microscope), select the Finder's Get Info command, and increase "Preferred size".

Why does the desktop change color when I run NIH Image?

NIH Image uses all but two of the 256 available screen colors when the monitor is set to 256 colors. The two "colors" that Image never changes are white (0) and black (255). Objects on the screen that are not black and white are likely to change color when NIH Image is being used. You can avoid this problem by selecting "Desktop Friendly" in Preferences, but this reduces the number of grays displayed to 16. If your hardware supports it, you can also avoid this problem by switching the monitor to "thousands" or "millions" of colors.

Why does text look ragged when I print an image on a laser printer?

NIH Image treats text as if it were part of the bitmapped image. To create high quality text for laser printer output and slide makers you need to export the image to a multi-layer, object-oriented drawing program, such as ClarisDraw or PowerPoint.

In NIH Image, white is 0 and black is 255, which is the opposite of what I'm used to. How can I change this?

Check "Invert Pixel Values" in Preferences. This sets up an inverting density calibration function, causing pixels values displayed in the Info and Results windows to be inverted.

Why does the Paste command sometimes get dimmed out?

Images copied to the clipboard are stored in the Clipboard buffer. In some situations, such as filtering, NIH Image has to use the Clipboard buffer for internal operations. When this is happens, the Paste command gets dimmed out.

  • How can I create a composite color image?

    You can't normally combine two images that have different LUTs, but if you check "Keep LUT" when you open the second image (which must be stored as a PICT file) its pixel values will be remapped to conform to the LUT of the first image. You will then be able to successfully Copy and Paste, since both images have the same LUT.

  • How can I convert a stack to a QuickTime movie?

    Save the stack in PICS format and open it in Apple's MoviePlayer program. MoviePlayer will automatically convert the PICS file into a QuickTime movie.

  • Is there help in understanding densitometry and/or gel analysis?

    There are a number of documents available explaning anything from portions of the theoretical principles of densitomtry, to step by step help in using the gel analysis macros. Those interested in densitometry should strive to understand NIH Image's Calibrate command and why it is used.

    For explanation regarding basic underlying principles of densitometry read the section of NIH Image Engineering on densitometry.

    For basic step by step explanation on the gel macros, the Techniques section of the NIH Image Manual should be read.

    And finally, for a longer and more thorough step by step explanation as to how to use the gel macros, refer to the Using Image for Densitometric Analysis of 1-D Gels manual.

    How should I cite NIH Image

    Published research assisted by NIH Image should use a statement similar to the following in the materials and methods section "... analysis performed on a Macintosh computer using the public domain NIH Image program (developed at the U.S. National Institutes of Health and available on the Internet at http://rsb.info.nih.gov/nih-image/)".

    Is there an NIH Image Home Page?

    The NIH Image home page provides on-line documentation, links to download the software, tutorials, links to other image processing software, an archive to search for answers to questions and more. The NIH Image home page is located at:

    http://rsb.info.nih.gov/nih-image/

    How do I download NIH Image using a Web browser?

    The latest version of NIH Image, documentation, source code, macros and more can be downloaded by going to NIH Image Home Page and following the "Download" link.

    How do I download the latest version of NIH Image via FTP?

    The latest version of NIH Image, documentation, source code, macros and more can be found on the anonymous ftp server zippy.nimh.nih.gov. Choose the directory directory /pub/nih-image. The best way to download the program is to use the user-friendly Macintosh FTP client Fetch..


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