Help using Iris

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loneoceans
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Help using Iris

Post by loneoceans »

Hi everyone! 8-)

If you didn't notice, this is my first post (I'm new on this forum!). I'm just starting out with some astrophography and I'm just learning how to use Registax and IRIS.

I've done some processing with Registax before for small photos of the moon a while ago. However, I am aware that IRIS is better for starry sky photos and the likes (vs planet photos), and that IRIS is better suited for large image files from SLRs (vs Avi from webcams).

I just took a couple of photographs of Orion and I'd like to use this as a starting point for stacking starry photographs. I tried to read up on tutorials but they all seem to begin with RAW files. However, is there a way to stack using JPG files? I'm quite confused about how IRIS works (since it's commandline mostly) and it'll be great if someone could help shed some light!

Basically I have 5 photos of the same constellation and I want to stack them in IRIS. Didn't take any dark frames. How should I begin doing that? If anyone could point me to a good tutorial website, that'll be nice also!

Thank you very much!
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Meng Lee
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Post by Meng Lee »

There you are, a tutorial website:

http://starizona.com/acb/ccd/ccd.aspx

By the way, please note that the algorithm behind stacking planets and deep sky pictures are different, so please do not be mistaken that Registax can stack deep sky pictures properly.

Thanks.
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weixing
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Post by weixing »

Hi,
It's quite simple. First open your file in IRIS and save in PIC format with a sequence number start from 1 as suffix in the file name. For example, if you got the following files:
IMG_5432.JPG
IMG_5433.JPG
IMG_5434.JPG
IMG_5455.JPG
IMG_5456.JPG

You can save the files with the following file names with a sequence number start from 1 as suffix:
IMG_1.JPG
IMG_2.JPG
IMG_3.JPG
IMG_4.JPG
IMG_5.JPG

You can use the "save" command to save the file. It is save as PIC format by default. For example, "save img_1".

After you do that, you can start the alignment process with the following command:
setspline 1
coregister2 img_ lmgreg_ 5

After the alignment command successfully completed, you'll have 5 new aligned image files created:
Imgreg_1.pic
Imgreg_2.pic
Imgreg_3.pic
Imgreg_4.pic
Imgreg_5.pic

Now, it's best to normalize the image to 0 before stack as IRIS is using 16-bits signed number. Use the following command to do that:
noffset2 lmgreg_ lmgnorm_ 0 5

After the normalize command sucessfully completed, you'll have 5 new normalize image files created:
Imgnorm_1.pic
Imgnorm_2.pic
Imgnorm_3.pic
Imgnorm_4.pic
Imgnorm_5.pic

Now you are really to stack. I usually use the kappa-sigma stacking. Below is the basic command:
composit lmgnorm_ 3 1 1 5

After the command completed, you'll have the stacked image displayed. Use the "save" command to save the image:
save stack

The stack image will be save in the file: stack.pic

Or you can use the following command to save as photoshop 16-bit format:
savepsd2 stack

The stack image will be save in the file: stack.psd
Please note that the image may look a bit odd or can't see it clearly when you load in Photoshop. Just use the "Curve" or the "Level" command on it.

Happy image processing and have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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chrisyeo
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Post by chrisyeo »

http://astrosurf.com/vdesnoux/virtualeq/virtualeq.htm

this might help, but Weixing's instructions are more up-to-date.
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loneoceans
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Post by loneoceans »

Wow thanks for the prompt responses!

I've followed the instructions and I've got IRIS to stack them together nicely! Thanks everyone for the help. Now I'd need to play around with it a bit more and explore further to improve my skills and processing.

*off to play around with Iris more!*

Once I get everything figured out I'll post some photographs. :-)
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loneoceans
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Post by loneoceans »

Wow thanks for the prompt responses!

I've followed the instructions and I've got IRIS to stack them together nicely! Thanks everyone for the help. Now I'd need to play around with it a bit more and explore further to improve my skills and processing.

*off to play around with Iris more!*

Once I get everything figured out I'll post some photographs. :-)
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