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cropping and combining images in Photoshop

red dwalf

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for this tutorial i`ll be using Photoshop CS3 


this tutorial will help you take out the bright cores of images and replace it with a less over expossed  shorter sub length area.


i`ll be including two images of M42, one of 20 seconds and one of 180 seconds,


open Photoshop and select the 20 second image and load it, then select the 180 second image and loan it, convert both images to 16bit format as usual. 




    Highlight the 180 second image by clicking on it and so you are working on that image,

on the top tool bar click "SELECT" then "ALL"

the 180 second image will now have black and white moving dashes round the edge of the image.

now click "EDIT" then "COPY" from the toolbar

now click on the 20 second sub image and from the tool bar again click "EDIT" and then "PASTE"

now the 20 second image will have two layers, original background layer and a new 180 second layer 1 on top of the background layer.

you can now delete the original 180 second image background if you wish.





your page should now look like above with two items in the layers tab.

the eyeballs on the left of the layers allow you to turn off and on that layer, usefull if using more than two layers and to see what the underneath layer is like.clicking on the layer box puts a white box around it to show you which layer you are working on, very important !


now make sure you are working on layer 1, the 180 second image by clicking on "layer 1" in the bottom right hand box.

now the good bit, select "LASSO" from the tool selection and draw around the area to be cut out.

select "ALT" on the keyboard, keeping finger on it then click on THE "ADD LAYER MASK" button, bottom right of the screen as shown below.




now make sure that the new layer you have just created in layer 1 is highlighted and click on "FILTER" then "BLUR" then "GAUSSIAN BLUR" from the toolbar.

you might need to up the "RADIUS PIXELS" to between 30 and 50 depending on how it looks, generally the more mega pixels the image has the more you need to bump up the slider, i just move it up alittle, wait a second for it to adjust and see what it looks like then when i`m happy just click on "OK"

now click on "layer" on the toolbar, then click "FLATTEN IMAGE" and you are done !




choose which format you wish to save the image in and where and your finished.

Edited by red dwalf
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Cool mate thanks for that all I need now is another tutorial from Steve as I cant get those images right lol

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