Meade DSI Pro LRGB imageing HELP !!

[teztwister]

Hi ,

What i need is some advice,i am just starting and dont know much about this type of imaging.I have got a Meade DSI Pro and a set of Meade filters and i am using a 8" lx90 on a wedge no guide scope or any thing.

Now i tried to use envisage last night,i took 5 images of 22 seconds each in L R G & B and saved them in Fits,save all uncombined images (dont know if this is right ) now i want to combine the images in to a colour image so what program should i use.

Is envisage the best capture program to use or is there something else i can use with a DSI Pro

Basically i need a dummies guide to imaging !!

Any info will be very appreciated

Thanks Tez

[greenkat]

Hi Tetz

Never done LRGB myself but I use envisage.

If you open envisage without the cam connected, you can open your files, click on the first file in the list, select options as you did when you were imaging, but select normal operation as your save option, and stack them. I would imagine it will stack the LRGB files and give you a colour image but could be wrong.

Or try using Deepsky stacker to stack them.

If you google matt taylor and dsi , he does a couple of dvd's about imaging with the dsi, thy are quite good.

Im sure someone else can advise you beter on LRGB thou :)

[RobH]

Hello Tez.

I started out imaging with a DSI pro, it's a good camera to learn with as it can be pretty unforgiving and teaches you good imaging discipline.

Yes, saving all uncombined files as FITS is correct.

What you then do, for a colour image, is stack all of your reds into a single combined image, then do the same for your green, blue and luminance.

After that, open your 4 resulting images, and, using the luminance as the master, align them all and save the results.

To actually construct the LRGB, I've always used photoshop.

I bought R Scott Irelands excellent and very thorough 'Photoshop astronomy' and the method is explanied clearly in there.

In a nutshell, what you do is first open your red image in PS.

Then go to....'IMAGE-MODE-RGB COLOUR'

This makes your greyscale red image into an RGB image.

It will still look grey, but if you open 'WINDOW-LAYERS'. you will see the layers dialogue box appear.

This has 3 tabs on the top.

Clik on the tab marked 'CHANNELS'

You will now see the RGB colour channels.

Now you have to copy and paste this into the green channel of your red image.

In the channels box, click on just the green channel. This will be highlighted in blue, meaning it is active.

In a small box to the left, there is a little 'eye' icon.

The top channel is marked 'RGB'

Click the box to the left of this. The 'eye' icon will appear.

This means that now you are seeing all the channels, but only the highlighted channel is active.

Open your green and blue greyscale images.

Make green image active by clicking on it.

Select all (CTRL-A), copy (CTRL-C), then click the red image to make it acive, and paste the green image into the green channel of the red image....(CTRL-V)

Do the same with your blue image, making sure the blue channel is acive by clicking on it.

This will now have produced a colour image.

In the channels box, now click the top section, the one that says RGB.

This makes all the channels active so anything you do from now on will affect all of them, not just one.

Now, on the layers box you've just been working on, click the left hand tab at the top.

This will show a single layer called 'BACKGROUND'

Make sure you can see the RGB image you just constructed, and the luminance image.

Make your Luminance image active by clicking on it.

hold down SHIFT, and left click on the 'Background' layer of the luminance image. Keep holding the left mouse button down.

Drag this over to your RGB image and release the left mouse button.

This should have put another layer over the top of the background layer of your RGB image.

In the layers box, you will see a small box that says 'NORMAL'

This is the layer blending mode.

It is a drop down menu, and the last choice is LUMINANCE.

Set the blending mode to this.

At this stage, you will have a LRGB image, but the colour will look very washed out.

Click the bottom layer to activate it (the active layer is always blue)

On the top bar, go to 'IMAGE-ADJUSTMENTS-HUE/SATURATION'

Bring up the saturation level to between 30 and 40.

That should make it look much better.

When you're happy, go to 'LAYER-FLATTEN IMAGE'

Save it as a TIFF.

For Jpeg, then go to IMAGE-MODE-8 BITS/CHANNEL

Save this as a Jpeg.

At first sight, this looks very complex, but you soon get the hang of it, and the whole procedure takeds me less than a minute these days!

Have fun

Cheers

Rob

[RobH]

I forgoot to say, the meade colour filters are not IR blocking. I made this mistake and got bloated stars and weird colour.

Get an IR filter and put it in the nosepiece of the camera.

Leave your meade IR filter in place so that all filters are parfocal.

Get rid of the slide, it'll let light in, and get an Atik manual filter wheel.

Cheers

Rob

[teztwister]

Ah thats exactly what i wanted to know thanks for that,I think i will print this of so its to hand.I will give it a go and see what the result is.This is just what a begginer needs to know

Again many thanks Rob !!!

Tez