UGC 4881--The Grasshopper

[Russ.Carpenter]

Now that 1.4 is working perfectly on my Mac, I’m making a concerted effort to relearn StarTools. I’m interested in interacting galaxies and have been concentrating on Hubble data.

Here is an exercise with the “Grasshopper” (UGC 4881). This image was captured in 2001 by the ACS camera, which uses two CCDs. In this screen capture of the initial AutoDev window, you can clearly see the separate images. In addition, you can glimpse a vertical band of artifacts which, in later stages of processing, become quite annoying.

Autodev.jpg (448.37 KiB) Viewed 3068 times

Wipe did a nice job of eliminating the gradients in the two images. And, as usual, the Color module produced saturated colors that are quite different from the colors in the NASA version. Life was superb in isolating the various galaxies from a noisy and distracting background.

For me, the most difficult job was getting rid of the vertical band of artifacts. There might have been a better way, but I had the most success by making a mask for Dust & Scratches, and then using the Heal module.

Here is my StarTools version:

UGC 4881 StarTools.jpg (179.99 KiB) Viewed 3068 times

And here is the NASA version:

UGC 4881 Dowloaded from HLA.jpg (382.07 KiB) Viewed 3068 times