Mars with good seeing - Jan 7th (UK)

On Wed, 09 Jan 2008 18:25:54 +0000, Anthony Frost
wrote:

In message
Pete Lawrence wrote:

The aim of the colour image is to try and bring out as much hidden
detail in the combined image as possible while still attempting to
keep a sense of reality to the colour scheme. Whether I achieve this
isn't really for me to judge as I'm too close to the image. As far as
I can tell (and I have compared a few images to a base Hubble image as
reference) I don't introduce too many things which aren't there.

Do you weight the three channels in any way? A lot of the pictures
posted by various people seem to me to have a very blue cast, in your
latest especially around and on the polar cap at the bottom. A set of
pictures of Saturn posted last year also sticks in my mind because of
the relative blueness of the highlights. I've a background in broadcast
TV and from memory the three channels were weighted 0.66 G + 0.23 R +
0.11 B when producing the composite signal from a camera or telecine,
and I've been wondering whether the same applies here.

Hi Anthony,

I don't tend to do it like that for the simple reason that my captures
are done at different camera settings and it's hard to be that precise
with the levels. It's also something I'm just not in the habit of
doing. However, I'm sure the same approach would apply and indeed
Registax does carry a luminance calculation based on the default
values of 0.299R 0.587G and 0.114B.
--
Pete Lawrence
http://www.digitalsky.org.uk

On Jan 8, 7:12 pm, Pete Lawrence wrote:
On Tue, 08 Jan 2008 09:15:28 +0000, Pete Lawrence

wrote:

Thanks for the comments. Here's the final version of this particular
data set.

http://www.digitalsky.org.uk/Mars/20..._Mars+800n.jpg

Exceptional image Pete! This is your best one yet (I know I have said
it before) and you seem to raise the standard yet even further with
each new result.

Good work!

Anthony.

--
Pete Lawrencehttp://www.digitalsky.org.uk

Exceptional image Pete! This is your best one yet (I know I have said
it before) and you seem to raise the standard yet even further with
each new result.

Good work!


And to think that 50 years ago Mount Palomar couldn't have produced an image
like that