[Quark (Trevor)]

Originally Posted by John Hothersall

Another good set with strong IR, if only I could get to this standard - anyway I live in hope.

John.

Thanks very much John, the 807nm IR filter really blocks a significant amount of light although it works well with large aperture scopes. A better alternative for smaller scopes may be the 742nm IR filter. I thought you might be interested in this info so have attached a link.
http://www.astronomik.com/en/astrono...42_filter.html

Originally Posted by Lester

Another good set of captures Trevor. Thanks for the views.

Thanks for your comment lester.

Originally Posted by mswhin63

Great stuff Trevor, wondering how you go with RGB on Jupiter and the effect on it rotation and the alignment. I must take time to change each colour and then combine or do you have a filter wheel?

Thanks Malcolm, the rotation is not a problem. My scope is on a GEM, each channel is captured for 50 sec's and I use a filter wheel. Allowing 10 sec's to rotate the filter wheel and start the next capture means that it takes about 3 min's to capture the 3 channels. When all channels are processed I align them on detail within the image, typically using the small white oval storms. This generally means that the G channel will be offset by about 1 or 2 pixels and the B channels by about 3 pixels. The detail on the planet will be aligned but the limbs will have a very slight blue tinge on one side and red on the other. I would think that unless this was pointed out that it would probably not be noticed.

Originally Posted by Shiraz

Excellent images for the conditions Trevor. The seeing down here was much as you describe - very good in R and pretty ordinary in G and B. It was almost like imaging through two different instruments and I was wondering if I had developed some chromatic aberration somewhere in the imaging chain. Wonder what the mechanism is for such a drastic change in seeing with wavelength?
regards Ray

Thanks Ray, it certainly has been an up and down year, thus far. The shorter wavelengths are far more effected by our atmosphere Ray, thats why the Moon appears red during a total Lunar eclipse, the longer red wavelengths pass pretty well unimpeded through our atmosphere, skimming the limb of the Earth and illuminating the Moon. If we have really stable air overhead with no shear or turbulence between layers then we have a higher probability of recording good G & B channel data.