Of course there IS a way!
You should put your rename string (set on the ingest dialog to be used for renaming your files) into the IPTC field instead of the {filename} variable.
However this won't work (properly) if you have a {seqn} variable in the renaming string, since it increases on every use so the filename and its use in the IPTC wouldn't match.
I usually use the 4 digits from the camera just change the strings before and add some after them. This way I can put the new filename into the IPTC on ingest.
I too wish there was an easy way to have the IPTC Stationary pick up the new name rather than the camera's file name. Can you explain the above a little more-- I'm slow.
Well I usually rename my images to have the date in the first 6 digits and 4 digit numbering after that followed by a letter identifying the camera body I used (since original camera numbering could conflict each other with the more bodies and it may be informative to see from filename which body I shot an image, especially when resolutions, crop factor or camera positioning if using remotes can carry a lot of information to you).
So my renaming string during ingest is usually last letter either set manually or automated with a special code replacement from camera serial number (but this part is not a topic here so I don't start long explaining this).
{year2}{month0}{day0}{frame4}a
{year2}{month0}{day0}{frame4}b
So the string I use in the ingest rename field can be simply used in the desired field of IPTC to have the new filename in IPTC as well. Actually I do use it in 3 different fields including the caption.
This method doesn't work if you use a {seqn} variable since it increases value every time you use it!
I usually ingest all images from all cards and if shooting on the same assignment with more than one bodies I do a capture time sort and rename the images to have a continous numbering in time order. In this case my IPTC will mismatch the filenames so I have to do an extra step reapplying the IPTC with {fbas}. But I'm a lazy guy so I tend not to rename them if not necessary. PM can allways sort me in any way after all...
,-)))
I hope this explains it more, but feel free to ask if not.