Original subtitles

last week we got into stacking with

Cyril using scripts this week let's take

a look at how to stack with xero without

scripts using serial is pretty

straightforward and this won't take long

and while a lot of people say they find

stacking without scripts to be somewhat

daunting it's straightforward once you

learn it and the detailed control yields

the best results you're going to start

by going to the home icon top left go

into the select folder window and

navigate to the folder of astrophoto

images that you want to process click on

the folder and select to open Ciro only

works with fits files which are common

in astrophotography so if you did not

record with fits files you can convert

them in the conversion tab the

conversion tab is the leftmost tab and

the control panel on the right now

navigate to the plus button in the

control panel and Explorer window will

pop up select all the relevant files and

click add the files will be added into

the control panel ready for manipulation

now choose a name for your converted

files or you can leave it the same if

you want and you can even convert to a

fit sequence or an Ser sequence if you

prefer

our purposes here we're just going to

convert to fits images once ready hit

the convert button unless you're using a

much older computer zero will convert

the files very quickly we're going to

blaze through 386 Tiff images here in

seconds

next up is the sequence tab in the

control panel just to the right of the

conversion tab but we don't have much

use for it here that's mainly for

manipulating large sets of images that

will turn into something like a dark

master in this example we won't be using

calibration frames such as darks biases

or flats at all we're just going to keep

it really simple

beside the sequence tab is the

calibration tab as I noted earlier we're

not going to use calibration frames this

time if you don't already know

calibration frames are your dark biases

flats and potentially dark flat frames

they are used to remove any

imperfections in your lenses or camera

next we need to go to the registration

tab here is where zero will align your

images in the control panel you'll see

the sequence stacking options the first

thing to choose is your method there are

five options we won't go through them

all here but if you hold your cursor

over the five options for a moment a

dynamic description will pop up that

will show you the pros and cons of each

option Zero's full of these Dynamic

menus they make it very user friendly

they're well worth stopping and taking a

moment to read in order for you to

understand what the various options do

and if you're unsure experiment try

stacking one way in then another or

aligning one way and then another and

you'll learn a lot about how it works

for our purposes here we're going to go

with two pass Global alignment it uses

multiple stars to give a very accurate

alignment and it also allows us to

choose which frame we want to use as our

frame of reference for stacking

personally I find this to be the most

useful option and use it pretty much as

my default

having picked two-star alignments we're

going to pop back over to the sequence

Tab and pick open frame list and from

there we're going to choose which frame

is best or at least seems best to use as

the reference frame this video is only

for demonstration purposes so I'm not

going to put too much effort into this I

think frame 17 looks pretty good just a

little bit more contrast detail there

probably just due to momentary favorable

atmospheric conditions but whatever that

frame is good enough for here for

registration Channel while we're working

with a monochrome image so our only

option here is luminance if you are

working with color you could pick one of

the color channels as well for the

transformation Channel you have four

options the default is homography with

eight degrees of freedom moving up you

have a fine or a fiend similarity and

shift at the very top each one of those

removes two degrees of freedom and each

has less and less tolerance for error

we're going to go with the shift option

which is ideal for images with no

scaling Distortion or field rotation

none of which are in our set of images

but if the images that you wish to stack

have lost precise mapping you might want

to use tomography or one of the other

options below shift

in the image selection section you can

choose to use all the images in your

stack or you can navigate back to the

sequence Tab and go to the open frame

list again and remove any images you

consider entirely unsuitable once you've

made your selection go ahead and hit go

register Cyril will now begin the

process of aligning all the images in

your stack this could take only a few

moments or a few minutes it depends on

how many you have in our case it'll take

a minute or two so we'll just go ahead

and jump ahead when it's done you can go

ahead and jump to the plotting if you're

curious and see if there are any

particular images you may want to remove

from the sequence before you begin

stacking I see a few rough ones in mind

but none I'm going to bother with for

the purposes of this informational

session now at last the stacking under

the stacking tab the first option is to

pick your method you could go with some

method many persons do and it works okay

but it's not quite the same thing as

saying it works well what we want to use

here is average with rejection which

performs several types of clipping that

will work as error correction and do a

heck of a lot to clean up the noise in

the slow information set of images after

you've picked through method you have to

choose your normalization you have

additive multiplicative and additive and

multiplicative with scaling the scaling

versions give us a better signal to

noise ratio so we're going to go with

additive with scaling we generally

always want to choose to increase the

signal to noise ratio

from there you'll have to pick your

preferred pixel rejection technique once

again the dynamic menus give you an idea

of which you should use as we are

working with several hundred images

we'll use the generalized extreme

student deviate test

and last we have to pick our weighing

method as always the dynamic menu should

give you a good idea which option will

work best for you I'll pick noise since

I want to minimize the noise in this low

information image and that's it now we

can stack here's where the magic happens

and that hard one sequence of dozens

maybe hundreds perhaps even thousands of

images transforms into an

astrophotograph

this is going to take a few minutes so

we'll go ahead and Skip ahead and take a

look at the final results

so our stack is just now coming to

completion when it completes we'll go to

the open Button top left click it and

find the appropriate file you'll know it

because it'll bear the suffix underscore

stacked dot fit now deep Sky objects are

dim so you'll still have to develop the

image to properly see it but at the

bottom center right of zero we can go to

the display mode options and pick Auto

stretch which gives us a quick rough

idea of what our finished image can look

like

there we go we just saw that dim little

hazy spot in the sky turn into a Galaxy

now I'm going to crop out the

imperfections along the Ridge and do a

really quick edit on this to show you

that with Cyril with some basic stacking

technique even without calibration

frames and even without a heck of a lot

of captured information you can get some

very beautiful final results so we're

just going to pop up to the histogram

transformation option and do a quick

auto stretch this will give us a good

sense of what the light of our galaxy

should look like it's pretty close I

think to the maximum that we want the

light now we're going to play with the

black level a bit via the generalized

hyperbolic stretch transformation option

and then adjust the Black Level just a

little bit more via the Asin or a side

option I'm not quite sure how to

pronounce it

I started to run a noise removal routine

but quickly removed it the routine

mistooks some of the beautiful contrast

and detail within the Galaxy for noise

so instead I'm just going to fine tune

my black level just a little bit then

we'll apply just a few more quick

touch-ups and it's starting to look

about like we want it to look stacked in

developing zero in just about 15 minutes

so next time you're stacking you could

use scripts if you want the scripts are

fast and convenient but if you really

want to maximize the power of serum

cereal is an incredibly powerful tool

learn how to stack manually it's not

that hard and for the detail and control

that it gives you with a little practice

you can really get some incredible

results

thank you for watching and if you

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