This is NGC 1850 and friends. NGC 1850 is at the center of the image, NGC 1855 is to the left (SE) of NGC 1850, and NGC 1858 is at the right side of the trio (SE of NGC 1855).

NGC 1850

NGC 1850 looks like a globular cluster – see this closeup view:

In fact, NGC 1850 is a double cluster and super star cluster and is composed of young stars. The only comparable object in the Milky Way is Westerlund 1 (also called the Ara Cluster). There are a total of 11 NGC objects in this image.

NGC 1855

This is a closeup of NGC 1855:

This is also a young globular cluster as indicated by the blue stars in it. The image shows lots of stars near the center of the cluster, all clearly resolved.

NGC 1858

This is a closeup of NGC 1858:

This is both an emission nebula and open cluster. The transition from the red nebula to the blue surroundings are very nice and natural in this image.

Acquisition and Processing Details

I took this image using iTelescope’s T32 telescope in Siding Spring, Australia. The image is made up of the following:

  • Luminance: 900 sec, no binning
  • Red: 600 sec, binned 2×2
  • Green: 600 sec, binned 2×2
  • Blue: 600 sec, binned 2×2

It cost me 76 points to get this image; I buy 40 points a month so it cost almost 2 months of points.

I processed this image in PixInsight and the xsif file (PixInsight’s native format) is over 197Mb in size; the TIFF is 98Mb because there’s so much data in this image. The color in this image came out really well – lots of subtle transitions and details in it.

iTelescope’s T32 is a Planewave CDK 431mm aperture telescope. I like this telescope and the ones that are similar to it because you can image during the transit, so you get the highest SNR.

Using Slooh.com To Get This Image

You can get a similar image using Slooh but you’ll have to book enough missions to get to the exposure times. Assuming you’re using Chile 2, you’d need about 30 missions to get the 600 second exposure time on this target, plus you’d have to book another six luminance-only images to get a total of 900 seconds of luminance on this target.

But that is the advantage that Slooh.com offers – regardless of how many missions you book, your cost remains fixed. So your cost per image depends completely on how many missions you book in a given year. The more missions you book, the lower your cost per mission.

Keep in mind that your Slooh.com images will be binned: luminance is binned at 2×2 and the R, G, and B are binned at 3×3 so your total resolution will be affected.

The one key advantage of using iTelescope.net is that I don’t have to include a logo on it, making it possible to sell this type of image if I wanted to do that.