Image quality

With Marvin Bean installed on my local desktop. I add structures into a Powerpoint documents, they show up nicely in the MarvinSketch popup, when double-click, see Figure A.png.





But it displays rather ugly in the Powerpoint slide (Figure B.png). I have resized the structures to occupy the whole slide. It seems the OLE plug-in is not aware of the dimension. Noticing the double bonds don't show as parallel, the dashed wedges do not look nice. Not good enough for presentation purpose.





A related question: is it true that one cannot have anit-alias for the stick display mode? (see Figure C.png, the lines obviously is not anti-aliased).





Thanks.

By OLE copy, an EMF (vector graphics) is embedded into the object. You see this EMF when paste the object into the Office document.


The vector graphics does not support anti-aliasing but it is scalable.


If you resize it, labels always are drawn fine. I admit that the sticks are not too nice in such cases.


If you copy EMF instead of OLE, the quality of the picture is better. It seems that the ugly EMF is a side effect of OLE copy.


We will investigate what can be the problem.


Anti-aliasing is available ony by bitmap images (PNG, JPEG, etc).


If you would like to copy an anti-aliased picture into PowerPoint, use image copy. In this case a bitmap will be pasted into the Office document. It looks nice but this image can distore by scalling.

I have to correct myself. There is not big difference between the result of OLE and EMF copy.


The quality depends on the scaling. If you resize the inserted graphics, you can find that state where the line distortion is minimal.

Hello,





I am having problems with the image quality when I export the data (from Instant Jchem) into Excel Sheets (.xls) a tool we often use to print our data in tabular form. The quality is not the best (using export, structure jpg or png size 200 x 200, p.e) and so I would like to know if there is a better way to export the structures in a better quality.





The second problem I have is to open the structures once exported (p.e. with Isis Draw installed you can modify structures with a doubleclick on them on the excel or word worksheet); what should be for this case the best solution.





Thanks a lot,








Christian Kowalewski





Pharmaceutical Institute


University of Bonn

How did you create the poor quality picture? How did you inserted it int Excel?


I have saved the content in Marvin into a PNG file then inserted it into Excel. The result is nice.


Probably, you have resized the PNG file in Excel that caused the distortion of the image.


In this case, I recommend you to use vector graphics (EMF) that is scalable without quality degradation.





About second problem: You need Marvin OLE object.


You can paste/insert Marvin structures into Excel/Word documents as OLE objects. In first view, it looks like a pasted image but when you take a double-click on it, a MarvinSketch will be detached with the structure. After commiting changes, the image is refreshed in the Excel/Word document (similar solution that Isis Draw provides).


As I know, in current IJC, this functionality works only that case if a desktop Marvin Beans has been installed. IJC guys are working on that IJC does that alone (without installed Marvin Beans).


Tim can tell you more details about it.

As you are using Instant JChem to generate the Excel file you will be generating image files in PNG or JPEG format as these are currently the only formats supported.


This uses the standard Marvin image generation capabilities and appears to give images of the expected quality (let us know if you see specific problems), but image files are not ideal for strucutres, especially if you are wanting to resize them.





We will be addding the ability to embed structures as OLE objects (but only on Windows) which will allow you to double click on the structure and edit it, and we also have a JChem4Excel product under development that will provide similar functionality to ISIS4Excel.





Tim

I recently compared ChemDraw and Marvin in Powerpoint. I have to say that the quality of ChemDraw structures looks nicer. Most importantly, ChemDraw OLE objects supports a transparent background, i.e., the structure looks nice on any slide backgroud scheme. Marvin's background is always white. Double clicking on ChemDraw objects responses faster than Marvin objects.

We are working on image transparency. Hopefully, it will be ready for Marvin 5.2.