Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: Rocket Pooch on Jan 26, 2004, 18:58:00

Title: Colour Saturation v's Detail
Post by: Rocket Pooch on Jan 26, 2004, 18:58:00
After playing around with exposure times on Saturn I've come to the conclusion if you take more frames with your images a little underexposed you get better colour saturation, you would probably get a better images if you went through all the frames you collect.

However if you go for a higher quality image and fewer frames you get a sharper but bleached image.  See examples below.

500 frames 5fps

(http://www.jumpers4goalposts.org.uk/images/Saturn20040124-459Frames.jpg)

2000 frames 15fps

(http://www.jumpers4goalposts.org.uk/images/Saturn20040124-2000frames.jpg)

Lastly if you wait long enough to get Jupiter high in the sky, the clouds come in and you kick yourself.

John thank's for the TAL3x loan it's brilliant for the money.  I'm going to put together a barlow comparison page, so if anyone has a 4x and 5x they would like to lend me let me know.




[ This Message was edited by: csuddell on 2004-01-26 13:41 ]
Title: Colour Saturation v's Detail
Post by: Rick on Jan 26, 2004, 19:29:00
If you really want detail then go for monochrome. I'm not quite sure why, but monochrome always seems to show more detail better.
Title: Colour Saturation v's Detail
Post by: Rocket Pooch on Jan 26, 2004, 21:40:00
Who knows?  I don't.
Title: Colour Saturation v's Detail
Post by: Rick on Jan 26, 2004, 22:30:00
I've a theory it has to do with the way colour information gets displayed, especially on CRT-type devices. The colour seems to smear things a bit, so only black-and-white looks really sharp. Trouble is, it often seems the same with print. That may be down to the inherrent lower resolution of colour printing though. Greg might be able to explain what's going on....
Title: Colour Saturation v's Detail
Post by: JohnP on Jan 27, 2004, 01:23:00
Hi Rick, Chris - Very interesting. First may I say Chris I am impressed with your Saturn - Your scope definitely looks like it is behaving itself & the X3 barlow has helped with image scale.

I imaged Saturn in B&W for the first time on 15 December 2003 (Chris you have already seen this)- my aim was to try & get as much detail in the ring system as possible. Attached is the result (I hope as this is my first attempt at posting a picture). Anyway I managed to record Encke Minima which is a first for me :smile:

(http://homepage.ntlworld.com/john.punnett/graphics/saturn/saturn004.jpg)

Cheers,

John.

[ This Message was edited by: Rick on 2004-01-26 17:59 ]
Title: Colour Saturation v's Detail
Post by: Rick on Jan 27, 2004, 02:01:00
There's definitely quite a bit of detail in that image. What scope were you using?

(You can edit your own posts via one of the little icons along the bottom of the entry. Moderators, that's Ian and me, can edit any post, so I fixed the link in the original and cleaned out the extraneous chatter.)

[ This Message was edited by: Rick on 2004-01-26 18:07 ]
Title: Colour Saturation v's Detail
Post by: JohnP on Jan 27, 2004, 05:18:00
Hi Rick,

Full details are on my webpage - I just found you can get to that by clicking the little House icon at the bottom of the message - I must admit I am very impressed with this forum layout & capabilities.

Anyhow, Image was taken with a 150mm Newt & X3 Barlow (the barlow Chris took his image with)- I used a Baader IRB & contrast Booster filter.

Cheers, John
Title: Colour Saturation v's Detail
Post by: Ian on Jan 27, 2004, 05:22:00
you wait for phpBB v2. Although I wouldn't hold your breath :wink:
Title: Colour Saturation v's Detail
Post by: Mike on Jan 27, 2004, 21:18:00
Chris,

Why don't you do a high resolution B&W image for the detail and use a good colour one for the colour information and combine the channels? I hear it works very well.
Title: Colour Saturation v's Detail
Post by: Rocket Pooch on Jan 27, 2004, 21:30:00
Could do I suppose, probably would not be very difficult either.

Now why didn't I think of that.