TRIA Image Processing Software from Quarktet
Software User Review by Joel Schmid
Disclaimer
I am in no way affiliated with Quarktet.com or acting as any
kind of spokesperson for any Quarktet.com product.
Introduction
It is the bane of every astro-photographer from raw beginner
to seasoned veteran – Focus.
Sometimes no matter what precautions you have taken to ensure
an object is in focus before starting an imaging run the end result is
slightly less than perfect. Whether it’s due to mirror shift, changing
temperatures, atmospheric seeing conditions, etc …. Some or all of your
results end up out of focus. Normally the fuzzy shots are tossed, or
you just try to make the best of them.
But what if you could actually do something to improve those
poorly focused shots so that you could use them instead of tossing them?
The sophisticated deconvolution capabilities of Tria
imaging software from Quarktet just might be the answer!
Deconvolution is the process of removing
the blur from the photograph by analyzing the image and developing a point
spread function (PSF) for it. The PSF is used to measure how
much the light from a star has been spread around the central point due
to poor focus. The softer the focus of an image becomes, the greater
the PSF. The image processing in Tria can measure the PSF of an image
in three different ways, and then be used to reduce the amount of PSF
in a new version of the image.
The result?
A sharper, more clearly defined photo in place of the original
blurry one!
I had never heard of anything that could be used to fix poorly
focused or soft images before until I was contacted by Jim Caron of Quarktet.com
with an offer to give his Tria image processing software a try. Since I
seem to have a treasure trove of fuzzy shots I wished I could pull out
of the junk drawer and get some results out of, Jim’s offer was quite
timely.
Installation
The Tria image processing software package is comprised of a
small zip file download, plus a small USB security key that you plug
into an open USB slot on your PC. The security key unlocks the
program’s ability to save your results and removes a grid from an open
image that discourages software piracy.
Installation is fast and fairly straightforward. I tested TRIA
on a HP 2.5 GHZ desktop PC running Windows XP SP3. The installation
required me to download and install Microsofts .NET version 3.55sp1
before continuing with the main install, but this presented no issues,
and the installation completed smoothly.
Tria is listed as compatible with Windows 2000, XP, and Vista.
The security key works on both 32 bit and 64 bit machines.
Program features
Tria can open a variety of image format types – including
JPEG, bitmaps, TIFF files, and FITS files. Tria can also convert a
color image to greyscale, and save color images to bitmaps, JPEG, FITS
and TIFF.
Tria can handle a fairly decent size image, provided the PC
has enough RAM. On my test PC, which has 1 gigabyte of RAM, I found
that attempting to work with an image larger than 2000 X 3000 pixels
resulted in very slow deconvolution operations. Reducing the image size
in photoshop to something like 1024 x 800 pix solved the problem. I
suspect that working with a larger image would require a PC with more
RAM. This was not a major issue however, as I could simply bring the
image back into photoshop after cleaning it up in Tria and re-sizing
back to its original dimensions.
Tria contains the standard set of functions for an image
processing application, including resizing, rotating, cropping,
contrast adjustments, etc. It also contains the main attraction of the
program with the three different deconvolution methods, along with two
more I had never seen before – Fourier transform
and image math.
The Fourier Transform converts an image into a complex image
that shows the distribution of spatial frequencies in the image. This
allows you to see how much dark sky background is in the image along
with how much fine detail representing stars and nebula are in the
image.
The math operations add/subtract/multiply/divide images pixel
by pixel, or an image and a number. I was not able to fully understand
the purpose of the math function in an astro image, but Jim Caron of
Quarktet explained it me like so:
“There are many uses, but here is an example on how it might
be handy. Let's say you have a 16-bit image, it has a noise floor of
1000 or so, signal that goes from 1000 to 2000, and then saturated
stars at 16000. Your goal is to save it as a 8-bit image. So you may
use the MATH to first subtract off the 1000 noise floor, and then
divide by 4 so the signal you want to keep is between 0 and 255 counts.
Then convert it to 8-bit using the Convert function.”
Deconvolution
Since Trias’ main feature is correcting poorly focused images,
I set out straight away to see if it could work any magic on a few of
my worst offenders.
Tria offers three different ways to improve a poorly focused
image. The regular Decon method requires that the
user provide a PSF for the program to work with. The best way to do
this is to give Tria a properly focused image to use for extracting the
PSF (point source function) . Tria will use the extracted PSF from the
good image to improve the fuzzy one. Of course you will need to have a
well focused reference image on-hand, which may not always be possible,
for example if you are trying to fix a shot taken at a once in a
lifetime trip to a dark sky site. Not to worry though, as Tria has a
deconvolution method that will work without any reference image at all.
The second method available in Tria is the SeDDaRA
method, which stands for “Self-Deconvolving Data Reconstruction
Algorithm.”
Say THAT five times fast.
Pronounced ‘Sa-DARE-ah’, it was developed by Jim Caron of
Quarktet.com as a fast and simple way of using a PSF from a properly
focused image to fix up a poorly focused one.
The SeDDaRA method also requires a reference image that will
be used to extract the PSF for use in the blurred image.
The third way to deconvolute a blurry shot is by far the
easiest and simplest method as far as I can see.
CARon Blind Deconvolution works without the
need for any reference at all. Instead, it approximates the PSF in the
image and assigns a value to it from 0 to 1. Selecting any decimal
number between these two values will apply a mild deconvolution for a
value close to 0 (ie 0.01) to a much more aggressive deconvolution for
a value closer to 1 (ie 0.75) You can experiment on an image by just
entering a number for the “alpha” setting in the CARon decon dialog box
and then click on the “GO!” button and see how it looks.
Example Image
So let’s see if Tria can fix up one of my example images of
the “trap” area in good old M42. Here is the original image BEFORE
applying the CARon Blind Deconvolution:
Pretty typical, right? I though I had the focus nailed, but
after a few hours the SCT mirror had shifted enough to start producing
shots like this.
Let’s see if Tria can do anything for me here.
Here is the same image after applying a CARon Blind Decon with
an alpha setting of .35 :
Not too shabby! Tria was able to tighten up the stars in the
trap, and pull out the missing detail and contrast in the nebula as
well as the “ribbon” that normally runs diagonally between the trap and
the three stars in a row.
Now let’s see what Tria can do if I give it a nicely focused
reference image and select the SeDDaRa decon method. Here again is my
poorly focused image :
And here is the reference image I gave Tria to use for
deconvolution with SeDDaRa:
The reference image was from earlier in the night when I
really did have the focus nailed.
In the deconvolution dialog box I set the two variables as
suggested by Tria’s HELP file examples and then click the GO! button.
Here is the result:
This is very similar to the CARon method above. The advantage
of the SeDDaRa function is that it tends to work better on images that
have more complicated blurring going on. Usually it takes a little
experimenting to determine which method yields the best results. Using
Tria’s compare function is a good way to compare
two deconvoluted images to see which one looks better. You could try
the CARon blind decon and save that as one result, then try the SeDDaRa
and save that as a second image. Then just open both in Tria and click
compare.
After seeing these results, I began to wonder if I couldn’t do
the same thing with an unsharp mask in photoshop. So I loaded my test
image in PS CS4 and gave it a run through various unsharp mask settings.
Nope!
No matter what settings I tried in photoshop, I could not get
the same improvements to the focus of the image that Tria was able to
accomplish.
I guess I’ve been schooled!
A few things to note…
While testing Tria I did run into a few minor issues while
working with my test images:
- Tria cannot open Canon raw cr2 files. If you want to fix an
entire nights worth of poorly focused images, you will need to stack
and align them first and save them as a .tiff or Fits file. You can
then use Tria to improve focus.
- Before you attempt to run a decon method on tiff file, you
will need to save the image without the alpha
channels. This shows up as a little checkbox in photoshop SAVE dialog
window that must be unchecked before saving the tiff file.
- When performing a decon, Tria leaves the decon dialog
window open on top of the final deconned image results. This makes it
difficult to know when Tria has completed its work. I expected the
dialog window to close when the operation was completed.
- The HELP files for Tria are also the users manual. A few of
Trias features are not well covered by the HELP topics as they should
be. There are also a few places were Trias ability to work on a color
image is contradicted by statements indicating an operation can only be
performed on a grayscale image. Quarktet hopes to revise the HELP
documentation to fix all these issues in the near future.
- There are of course limits to how fuzzy an image Tria can
fix. There is no substitute for good sharp focus in the first place.
Tria is best at fixing mildly out of focus photos. It should not be
used for a shot that looks like a bunch of amorphous blobs in a sea of
black.
The Verdict!
So what do I think of Tria?
Is it the grand savoir of all things soft and fuzzy in
Astro-Photo land?
Well, if you have a bunch of shots that would otherwise be
throw-aways because your mirror shifted or the temperature changed
while taking the shots, Tria can give you a noticeable improvement in
the final stacked file. After spending all the time and effort to
capture an astro-object, that makes it worth the price of admission!
Want to give Tria a try?
You can checkout Quarktet’s latest version at http://www.quarktet.com/TriaDemo
You can download the free demo version and see what it can do
on your own images. If you decide that Tria is for you, you can
purchase a full version and a USB key for $360.00.
Future upgrades for Tria are free. |
