Log in

View Full Version here: : Hep, Help What Have I done


leon
14-05-2008, 09:06 PM
Hi Guys,

Well I know I'm new at this Mod stuff, so what is suppose to happen, could someone please advise me.

I put the Modded 5D on the scope, focuse and that sort of stuff is fine.

I know that there is some general light pollution, which has always been here, and then the Moon is pretty high and bright as well, but I just wanted to try out the Modded Camera, and boy, did I get a shock.

Every thing is pink, and appears hugely light polluted, and at only a 4 min exposure.

Is it normal for the colour to be this pink, and dose the modded camera pick up more light pollution as well, dose this all come out in the stacking etc.

What should be the general way to go about this please, I'm totally lost, maybe I'm expecting to much under these conditions, could some one please give me some tips on how to go about it.

Leon

[1ponders]
14-05-2008, 09:26 PM
Sounds about normal Leon. What you'll need to do is colour balance your images in PS when you process them.

leon
14-05-2008, 09:31 PM
Thanks Paul at least that is a start, but do i expose shorter or the same as I used to.

Leon

[1ponders]
14-05-2008, 11:37 PM
Depends on what your are shooting Leon, but unless your getting over exposure with your old system then longer is better. The longer your shot (until sky background or over exposure gets you) the better your signal to noise ratio.

If you want to deal with the pink then you can do that using Levels in PS. Set you black point colour picker in the levels dialogue box to something like 15, 15, 20 (rgb) and your white colour picker to 245, 245, 245. Then click the black colour picker on the darkest part of your image (apart from any vignetted areas which will be un-naturally dark anyway) and the white colour picker on your brightest star. This will quickly balance you initial colour for further processing.

Do you have the book Photoshop Astronomy? There is a very good section in the Levels chapter on how to do this and use the Threshold option to determine the darkest and brightest parts of your image.

Good luck with it.

leon
15-05-2008, 08:17 AM
Thanks Paul, I will go back to school and do some more learnig.

Leon

dugnsuz
15-05-2008, 08:21 AM
Hi leon,
Any chance of posting a jpeg to see what us potential modders will be up against!?
Cheers
Doug

gbeal
15-05-2008, 08:39 AM
What's wrong with pink, very fashionable.

RB
15-05-2008, 10:41 AM
LOL Leon, welcome to the hiden Universe.

Gary you crack up.......:rofl:

leon
15-05-2008, 01:47 PM
Now Guys this is not funny, this is serious stuff. :lol:

Leon :thumbsup:

h0ughy
15-05-2008, 02:00 PM
MMMM you make me wonder sometimes Gary???:lol:

JohnG
16-05-2008, 10:07 AM
You been sniffing that Jet A1 in the morning :lol:.

Cheers

John G

Suzy_A
16-05-2008, 01:08 PM
Modding a camera by replacing the UV/IR filter makes the camera much more sensitive to the red and IR - so the images come out pink. There may also be a haze caused by the extended UV sensitivity, so you may also need a UV and long-wave IR blocking filter.

As someone else wrote, for astro, you need to do a colour balance, both with the camera and with software. For normal photography, you also need a UV/IR blocking filter over the lens or behind the lens as well to get the correct colour.

Have a look at http://www.iceinspace.com.au/forum/showthread.php?t=15205&highlight=30D+UV%2FIR+filter for some examples of photos with and without various filters and white balance settings.