Log in

View Full Version here: : M83, a work in progress


anthony2302749
21-05-2006, 01:01 PM
Well the weather gods must have been smiling; finally clear skies so out came the astrophotography gear for my second attempted at M83. This image is an improvement on my last. Autoguiding work a lot better this time around using the ST-7/ED80 combination, focus was much better as well on the SCT. Dark frame and Flat frames were also taken for post-processing of images. I was not happy with the flat frame as it was more or les done by shining a light on the shed wall and taking an image. The finally result was an uneven flat frame which I think is evident in the final image.

Finally about the image: 8 x 5 minute exposure @ 800ASA with DSLR Focus, autoguide with ST-7. Dark and flat frame subtract and aligned with MaxDSLR. Cropped and processing with Photoshop. Reduce by 20% and converted to JPEG for uploading

Anthony

strongmanmike
21-05-2006, 01:28 PM
Well Tony

That's actually quite a reasonable image!
Can't believe the flat you described actually helped.???:scared:

Is this a crop from the original?

More colour is begging to come through but what is there looks quite balanced, well done. Do you know how to use layering in Photoshop? Layering will allow you to bring out the core detail.

Adjust levels and curves so that you have two versions of the M83 image, one that shows the detail in the core, the other with the core burnt in but showing the outer fainter bits. Now open both versions in photoshop, chose the detailed core version and select all and then copy and paste it onto the burned out core version. Now lasso the core region, feather 20 pixels, then select inverse and then press delete. This will basically paste the detailed core onto the burnt out core version and have the faint outer stuff as well! :thumbsup:

Hope that was clear...? :)

Mike

anthony2302749
21-05-2006, 08:38 PM
Hi all

Here is a reprocessed image of M83 that I did this afternoon.

Anthony

strongmanmike
21-05-2006, 11:16 PM
Looks a bit better Anthony, did you use the layering I suggested?

Now to get rid of that blue background by playing around with the different colour sliders in Levels in PS.

Mike

Striker
22-05-2006, 12:36 PM
Nice image Tony...

Mike...when you say feather 20 pixels...how is this done in PS...not familiar with this term.

iceman
22-05-2006, 12:43 PM
When you make a selection, look up in the toolbar.. there's a box there that says "feather".

It's basically making your selection "gradual" by the amount specified, so you don't get a hard line of where your selection is, and where it isn't. It's like it's fading them into each other.

Like a colour gradient from black to white for example.. you can have black, and then white, but if you have a "feather" of say 20px, then you'll have black, then over the next 20 pixels you'll get varying shades of grey until you get to white.

Hope that example helped to make it clear? :)

Striker
22-05-2006, 12:52 PM
Your not the Mike I was asking but what the hell...any Mike will do...thanks Ice....will have a play.....lol

strongmanmike
22-05-2006, 08:34 PM
Hey I'm Mike!...and so's my wife! :lol:

(Life of Brian fan)

Mike (Salway not me or my wife!) explained it well :-)

Mike

Doug
22-05-2006, 09:46 PM
Hi Anthony,
My Scope still hasn't come back from Meade hospital, :sadeyes: so I get a bit fidgety.
Here is a touch up additional process in PS of your second image.
How do you like the dust lane rendition?
If you are interested I will post the procedure.


best,
Doug

anthony2302749
23-05-2006, 11:40 AM
Looks good Doug, could you post the procedure for one and all to read.

Anthony