Here is David Malins enhanced Schmidt plate for a comparison
Aah that is interesting. I see 2 faint spiral arms above and 2 faint spiral arms below. Most images do not show the bottom 2. They usually show 1 of the top 2.
I wonder how many hours of exposure that will take.
Here is David Malins enhanced Schmidt plate for a comparison
Quote:
Originally Posted by Alchemy
Sorry, the image I looked at was the 1 Meg when i looked at other versions of the same image, And yes poor choice of words on my part.
Perhaps I should have just said, the color doesn't quite seem there.
Yes the light shades of blue are a tad off. Although the scope may be picking up the dust more prominently. I saw similar when I imaged it with an RCOS 12.5 inch. I think I'll switch to 2x2 binning for the rest of the colour. I've been using 1x1 and that gives better resolution but loses some potential signal.
Impressive start Greg. There's going to be so much to learn and your colour balance and processing will no doubt take a while to get a feel for too. We all want to get going quickly, but in the end its half the fun that's nothing is easy in this hobby of course. Will be watching with great interest, and thanks for showing this early effort and describing the voyage for the rest of us.
Learning the gear is part of the fun, I find it enjoyable finding out the best way to handle it. Nice and clear tonight although very windy. I should pickup another 5 hours on this one tonight. Fortunately my observatory is very well placed and wind is far less of a problem than it could be.
Always good to read about other experiences and opinions.
Any example piccies
I am not sure that having 1:1:1 filters is really all that big an issue given that the QE spectral response of every CCD is so significantly different.
Yes - It makes life "easier" if you are doing it quick and dirty, but . . .
Some CCDs peak in the Red others in the green and some even in the blue the variation within the visible range can be up around 30% on some CCDs.
Funnily enough a friend just sent me a compiled graph of all the popular chips yesterday in relation to an asteroid we missed and why we might have missed it !!!
All OTAs introduce some degree of cast anyway - even if its miniscule - there will be variance.
Then there is up to say 10% variation (reduction) in the ADU count for the Blue end of the spectrum compared to Red just by atmospheric extinction dependent upon your imaging Alt (angle).
At the end of the day you really need to do a G2V white balance if you want reliable and consistent results - an image session across a few hours from say 40°alt to Zenith is going to skew your results considerably for the same exposure times.
If you are going lower then maybe there is a 20% difference to deal with !
If you are ignoring that then you won't be colour balanced anyway !
So the issue of 1:1:1 filters becomes moot - to a degree since these other things over whoch you have control of are going to effect things to a far greater degree.
The order in which you shoot your RGB subs is probably going to influence the result to a much greater extent !
Worth noting that some of your image scheduling and capture software can automatically provide the relevant compensation factors for all your subs for this.
