M51 medium-high resolution

I put the ST-10XE camera in the C14 last night, and imaged at prime focus. I have previous used the ST-10 with an f/5 Optec reducer, but with the excellent seeing at New Mexico Skies, it seemed reasonable to try for ridiculous levels of resolution.

The seeing was about average, but the results were anything but. This is 20 minutes of luminance exposure of M51, binned 2x2. (A separate test binned 1x1 is underway right now; results will be posted later.) For this test, I used the automatic temperature compensation feature of the TCF-S; I did not attempt to tweak focus between exposures. That remains to be tested.

I applied a little deconvolution to bring up the sharpness a bit. I really needed more exposure to get good deconvolution, however.

Ron Wodaski
http://www.newastro.com/remote

Attached Image:

hi Ron,

Looks like those NM skies can support hires imaging. The combo you ued gave about .7 arcsec/pixel, I guess which can give a FWHM of about 1.8 to 2 arc sec. For me where I am in PA that's what I get on my very best (very few) nights.

It would be interesting to see how the ST-10 at 2x2 binning compares to the 1000 unbinned ( I think in the past I saw some of your images made with the ST-1000 ). I think the 1000 would be more sensitive at the native FL. (?)

An interesting question in my mind re hires imaging ( defined in the SBIG group as 1 to 1.5 arcsec FWHM) is ...for aesthetic purposes only at what point does reslolution make a difference? For very small objects such as planetary nebulas (less than 1 arc min in size ) the gain in visual impact seems intutitively obivious. For larger objects such as galaxies which can be quite large ..the question is unanswered. It would be interesting to compare images say of m51 presented at the same size (say 1100 x 800 or 800 x 600 ) taken at different pixel resolutions (ie at .4, .8 and 1.2 arcsec/pixex or whatever)and see what they look like.

Oh well just some meandering thoughts over my morning coffee.

Keep shooting the stars, the images are great and I look forward to seeing them.

clear skies,


Larry Citro