Just picked up an ST-10XME CFW8a+LRGB Ha

Hi all,

I just bought an ST-10XME with the CFW8a and filters. Should be an upgrade from my ST-2000XCM (which is for sale by the way)

I have a couple of questions and thought perhaps I could "ask the experts"?

1. It is the blooming version of the camera and the previous owner sent me photos with terrible looking blooms streaking from the brightest stars - I presume these should be easy to get rid of? What is the best way to process out the blooms?

2. I have read some reports of internal reflections off the CCD coverslip can cause halos around some bright stars - Is this really an issue?

3. I'm concerned about the possibility of vignetting through the 1.25" filters when coupled to my NP-101, should I be?

Thanks in advance for any advice,

clear skies,

Jeff

Congrats on the new camera Jeff,should serve you well.

Jeff,

I will comment on my experience with my FLI CM-10, which has the same chip as the ST-10XME.

The chip is incredibly sensitive, both to light from the scope and to stray light. That high sensitivity is both a blessing and a curse. It will bring out the faint fuzzies really well, but will bloom almost instantly if there is a bright star in the image, and light pollution can be a problem as well.

The small blooms are pretty easy to deal with, especially if they don't cover anything important. But the HUGE ones can be really tough. MaxIm does a pretty good job of removing them. I have also used the DeBloomer plugin, which is more powerful but takes some time to learn how to use. CCDStack also has some really nice tools for deblooming, including a method for replacing the area that was wiped out by the bloom, but replacing it requires rotating the camera and taking more exposures, which is a little inconvenient. For me, the blooms were specially problematic for imaging nebulae, because they always seem to wipe out something important.

I personally found the vignetting through 1.25" filters to be pretty bad, but I was using it at F/3.3 and F/3.6 on my scopes. The NP-101 should not be as bad in that regard. The vignetting can be "fixed" with flats, and the flats will make the image "look" even to the corners, but I am sure that the frames lose detail there just due to lack of signal.

I can't speak directly to the internal reflections, because I always assumed that mine were from the filters. I never noticed that as a problem.

Despite all the difficult things about the NABG chip, my CM-10 is now at FLI for an upgrade to the new Microline system. I plan to use mine for narrowband work, which really benefits from that high QE. Many of the great images I have seen over the years were taken with that chip, so it is certainly capable of taking excellent images. I plan to use my upgraded Microline version for many years.

That is my 2-cents worth. I'm sure you will produce some great work with the camera.
Cheers,
Tyler

You'll love the high QE on the ST-10, Jeff.
Don't worry about the blooming, it's not that hard to fix.
I don't know what processing program you're using but if you have CCDStack or Photoshop the principles are the same.
If your blooms are small, you can get away with 'imputing' information from surrounding pixels to fill in.
When blooms are large, I like to take an extra set of short exposures where there's no blooming. Layer the two masters together and set the blooms to 'transparent' (in CCDStack) or use a mask (in Photoshop).
The data from the short exposure master can also be used to provide star color to saturated stars in the long exposure master.

dan