Creating isolated images of overprints

Thanks, khj , Kim!

I don't think I posed my question very well.  What I meant to ask was *how* dcstamps created the isolated overprint images.  I've had some in mind to do myself for other countries, as well as some cancellations.

But, on a related note, that cross-reference chart by Yanstan is very impressive!  I've developed a personal cross-reference between the Sakura & the JSCA Japan Specialized & Scott (at least through 2001, when I last stopped working on it), but wouldn't dare publish it for fear of the heavy fist of Scott in my face.

*Edited to add:*  Or maybe I'm failing to follow a link to Michael's pages properly?  Does he explain it there?

Dave I have extracted overprints before, but the results are somewhat mixed. The first thing of course is to get a good overprint, dark and clear. Having it on a stamp printed in a light color is a huge bonus.

I use two programs for photo processing. Photoshop Elements is the one I normally use for my stamps to put in my album. It OK, for many things. What I use for my photography is ACDSee, which is far more powerful, but only for photos. (I often use it to adjust the white balance of my stamp scans, because my scanner tends to scan with a yellowish tone).

Here are the major steps.
1. Search the internet, literature, catalogs and everything else I have to see if it has been done before.  Actually, most Steiner pages have extracted overprints, but I don't have access to them.
2. Search again
3. Find a good, clear and dark overprint on a stamp printed in a light color.
4. Get a good high res scan of the stamp  (I use 600ppx)
5. Sharpen just until you get artifacts   
6. Increase brightness and reduce contrast until you get the best image you can.
7. Play with other tools in your program, some work some dont.  I find it hit and miss, depending of the colors of the stamp and the overprint
8. Crop close to the overprint, zoom in and fill in any holes in the middle of the overprint from the process
9. Save picture as a jpeg, load up and darken if necessary.

To be honest,  I am happy if I get a good overprint, even if you can still faintly see the stamp in the background.

No secret, just keep trying different things, and most of the time you get something descent (again the key is finding a good original overprint with a lighter colored stamp).

Hope this gets you started
Michael

My thanks to you both for your replies!

Michael, your steps make sense.  (Especially steps 1 & 2:  Search.  ...  Search again.  )

I'll start dabbling in this in the coming days and see what kind of results I can come up.

I realize, as this little mini sub-thread has evolved, that I'm probably just as interested in extracting postmarks and ancillary markings as overprints, and so there are likely to be fewer examples available than an overprint.  Nevertheless, I'll start futzing around with this.

I used to use Photoshop Elements, but ended up needing to migrate to regular Photoshop in order to do batch image processing.  I discovered my need for this not long after Adobe went to the subscription model, rather than outright sale of the software, so I'm on an annual plan with them.  Aside from my resentment, the upside is that the software is always the latest version, and any tools or tricks I find out there on discussion boards tend to work, since nearly everything in Photoshop is backwards compatible, I've found.  And it comes with Adobe Bridge, which has turned out to be the image management software that I needed (but didn't know I needed until I started working with it).

I do still do a certain kind of image resizing and renaming in Irfanview because it's easier than in Photoshop & Bridge.

Like Kim, I did start down the Gimp road at one point, but got stuck, and, over time, figured out that Photoshop really addressed my needs squarely on point.  So I just turn over $10/month to Adobe and try not to think about it.

Anyway, in sum, I'll let you know how it turns out.

Thanks again to you both!  

(And apologies for this little sub-thread.  A real Easter egg amidst the Turkey discussion!)