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View Full Version here: : 47 Tuc with 12.5" f/5


John K
29-09-2014, 04:02 PM
Hi guys,

Visited the the ASV's LMDS site in Vic over the weekend and snapped about 100 mins of data on 47 Tuc.

Image is a combination of 30, 150 and 300 second exposures with a modified Canon 400D and JMI NGT 12.5" f/5 scope.

Although I am happy with the size and star density of the image, one thing I was not able to do is to get some star colours happening. Even at 30 seconds at ISO 400, there was very little star colour suggesting that perhaps either my DSLR could not pick up some of the yellow star colours I have seen in other images on the outer part of 47 Tuc, or that even the 30 second shots were over exposing the colour of the stars.

In any case, comments welcomed - the biggest area I am struggling with as well with my modified camera is the colour balance area/star colours.

Higher res here:

https://www.flickr.com/photos/johnkazanas/15385367771/in/photostream/lightbox/


Clear skies.

John K.

RickS
29-09-2014, 04:13 PM
Looks good, John. Getting star colour often requires a saturation boost (or equivalent CIELAB colour boost.) Did you try that?

Cheers,
Rick.

SimmoW
29-09-2014, 04:28 PM
Nice John, I took my last 47 Tuc shot there too at the star party.

What processing software do you use?

Even at 5 mins I wasn't overexposing (I think) and getting some colour. As rick says, it usually takes a bit of saturation boosting (masked!).

Also, using your software to normalise the colour balance helps, eg pick an area you 'know' is white & white balance.

Ross G
30-09-2014, 09:49 AM
A nice photo John.

Sharp and detailed.

Ross.

John K
30-09-2014, 01:45 PM
Thanks for the comments guys.



I use Deep Sky Stacker and CS3 to process my images.

Have been able to get some colour out of my stars by re-stacking and playing with the colour balance in DSS and then increasing the saturation.

Still not as good colour in the stars that I have been able to get on other objects and get from other images.

John K.