Posted by
Guy Cox-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Preparing-figures-for-publication-PPI-vs-DPI-tp5232491p5242537.html
A 1024 x 1024 image at 300 dpi will be reproduced at 3.4 inches wide.
This may not show your fine detail. If you want to make it a full page
width image you should resample to 2048 x 2048. This will then be 6.8
inches wide. If it's a high-quality journal using 150 dpi printing you
will then have 1 half-tone dot per (original) pixel. In practice, this
will look pretty good, in spite of my theoretical discussions. Since
you won't actually be able to see the dots in the printed image, you can
check if this is adequate by printing the image at that size. If
important information doesn't show, you'll have to enlarge part of the
image.
Guy
Optical Imaging Techniques in Cell Biology
by Guy Cox CRC Press / Taylor & Francis
http://www.guycox.com/optical.htm______________________________________________
Associate Professor Guy Cox, MA, DPhil(Oxon)
Australian Centre for Microscopy & Microanalysis,
Madsen Building F09, University of Sydney, NSW 2006
Phone +61 2 9351 3176 Fax +61 2 9351 7682
Mobile 0413 281 861
______________________________________________
http://www.guycox.net
-----Original Message-----
From: Confocal Microscopy List [mailto:
[hidden email]]
On Behalf Of Johannes-P. Koch
Sent: Thursday, 1 July 2010 5:54 PM
To:
[hidden email]
Subject: Re: Preparing figures for publication --PPI vs DPI
Just to get it right:
Say, I have a CLSM image with 1024x1024px, which was acquired at exc/em
488/520nm using a 63x NA1.4 objective. The zoom factor was adjusted for
Nyquist sampling, let's say such that I have 50nm pixel size.
I have to use these settings, since I want a whole human cell on my
image and I need the resolution as well.
If I consider now the second part of the Nyquist theorem, I would have
to use at least 2 pixels on the print for one pixel in my image - this
would be some 6.8 inches for a 300dpi printer!
This is obviously not feasible anyway! I assume, that only something
like 256x256 px are acceptable for todays image sizes in journals. This
would imply that either I am not "allowed" to use high NA objectives
(because then my field of view is rather limited if I stick to Nyquist)
or I have to crop excessively such that the whole context in a cell is
lost (see settings above). I suppose, you all agree that neither is a
solution. Then, the question remains for me: How can I properly transmit
such an image to a journal. The answer according to all of you is
simply, that it is not possible!
Am I right? This is disastrous.
Johannes
Am 30.06.2010 21:57, schrieb Craig Brideau:
> On Wed, Jun 30, 2010 at 8:29 AM, Robert J. Palmer Jr.
> <
[hidden email]> wrote:
>
>> 1) does anyone actually read paper journals? One can lament or
applaud the
>> trend towards "electronic only" but it is unstoppable and makes some
of this
>> discussion irrelevant.
>>
> I have to say that 99.9% of the papers I read are PDFs I view on my
> monitor. Occasionally I will print one out if I want to show it to
> somebody else, but I usually just forward it via email. That said, it
> is odd that I am viewing an image downsampled in a PDF. I think it is
> worthwhile to have a downsampled 'thumbnail' or 'preview' image in an
> electronic paper to keep the file size easily emailed/portable.
> However, I think critical images should be hotlinked to the original
> data. That way I could click on the placeholder/thumbnail image and
> get the raw data to make my own assessment against the author's
> claims. The tricky part would be to have a static location to store
> the raw data so that the links in the PDF stay good. Also, the reader
> would have to have an appropriate application to open the data, so
> something free and common, like Fiji/ImageJ would be required.
>
> Craig
>
>
--
Mag. Johannes-P. KOCH
Department of Biochemistry and Cell Biology
MFPL, University of Vienna
Dr. Bohrgasse 9/5
A-1030 Vienna
Austria
phone: 0043 1 4277 52809
fax: 0043 1 4277 9528
mail to:
[hidden email]
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