1

Topic: Pixelized Spectra

Hi to all mass spec people,

I would like to exploit the possibility of using mMass for my work. Specifically, I am exploiting the possibility of using the exported spectra from the mMass, for publication quality figures. Playing around with a spectrum and after exporting it to a vector program and printing the figure, I have noticed one thing that personally I find it a drawback (of the otherwise perfect program) and restricts me from using it. The aforementioned printed figure looks like "pixelized" and I think this is happening because it draws all the isotope pattern, in a way that the isotopic vertical lines protrude from the main line making the spectrum looking like pixelized (I hope you understand what I am talking about).

Would it be possible to do something with it, or is it something that I a missing?
Nice software,
Thank you.

2

Re: Pixelized Spectra

Hi,
could you please send me an image to show what exactly you mean? (support at mmass.org) I am not sure I understand it correctly.

Anyway, the best way to export spectra from mMass into vector format is to print the spectrum into PDF. To achieve a specific size, you will have to define a special paper in your printing dialog. Sometimes it is also good idea to play with the font size of axis and labels. You can also use direct export into raster image and specify resolution and size.

One final note, mMass uses a simple trick to be able to print or even show the spectra. It would not be possible to show full profile spectrum from high resolution instrument like FT-ICR having more than two millions of data points in a reasonable time. Therefore mMass considers a resolution of your screen or a printer and removes lots of data points, which otherwise would be shown on the same "pixel". For printing, it uses 5 "real pixels" as a default limit. If this value is to high (you can see sort of "pixelation") then close mMass and locate the "configs/config.xml" either in mMass folder (Win) or in "Library/Application Support/mMass/config.xml" (on Mac) and locate the "printQuality" parameter. Change it to any lower value.

3

Re: Pixelized Spectra

Hi again,

I realised that maybe I should have posted my message to Bugs and Troubleshooting. Apologies.
OK. Info will be sent.

Best
A

4

Re: Pixelized Spectra

It works. Thanks.

Reducing the value is decreasing/disappearing the pixel thing.

One more question though: Decreasing the PrintQuality value, will have any effect in the intensity of the peak at the screen or when printed?

5

Re: Pixelized Spectra

Hi, it does not have any effect on the peak intensity. It only describes how "precisely" the peak shape is drawn.