First Attempt at LRGB...

[JohnP]

On Friday night it was clear in Bromley although, by the sounds of it Headcorn was clouded over...

Anyway I managed to pop out & try my first LRGB image using the SC3 & MN56. Image is of M57 details as follows:

L=80 X 12sec
R,G,B = 15 X 12secs

It was quite a learning curve figuring out how to do an LRGB in Photoshop - also because I don't have a filter wheel I had to take the camera out between exposures to change the filter which also meant I had to figure out how to align & rotate images... Thks Chris for Stella Magic tip.

Anyway here's the image...

[Fay]

John,

That is the clearest image I have ever seen, you must be very pleased.


What does LRGB mean, is it the colour of the filters? If so, what is L?

Fay

[JohnP]

Thks Fay - I was just pleased to have figured out how to do LRGB An LRGB image is a high resolution colour image acquired using a B&W camera (like my SC3)

Basically the L is for luminosity - You  just take a black & white image with no filter (you could also use a Ha or SII for the L) - This image needs to be as long as possible because it is what will give the image all its detail.

The RGB are images taken through Red, Green & Blue filters respectively. These images can be a lot shorter than the L (typically 1/3 the time) & just provide the colour information.

Once you have taken the 4 images you can then combine them all in Photoshop to produce a high resolution colour image...

Sounds easy but I can assure you it isn't... especially when like me you haven't got a filter wheel which meant that each time I took an image I had to take the camera out, change the filter, put it back in & refocus etc....

It's a long old process....

Hope that helps,  John

[Tony G]

Lovely image John, and they do say 'you can never rush a goog thing' and as you see it may have taken a while to process the image but i bet you it was worth the wait.
Keep it up.

Tony G

[JohnP]

Thanks Tony... I'm working on sorting out autoguiding which will hopefully mean I can take longer exposures without drift.. What I have learnt with all this deep sky stuff is that if you want to do it properly you need to just concentrate on capturing one image per session.. don't try & grab lots of images in one night...

It's all good fun...

John

[Whitters]

Nice one John, that camera is a beauty