[arad85]

Hi all,

After some processing of one of my images by Clayton, I thought I'd have another go. My first attempt at processing the .avi file led to this:



and Clayton with some judicious use of sharpening/despeckling got to this:



so following the lead on deconvolution filters, I restacked and processed the same .avi to come out with the one below:


Do people think of it as an improvement?

[resonator77]

nice one Arad85

did you use your dobsonian to take these shots?
I believe you used web cam not a DSLR

quality Jovian images

[arad85]

Hi resonator,

No, these are taken with a C9.25 SCT. Webcam - yes, a Philips SPC900NC

Thanks - the seeing that evening were quite bad, but I'm learning how to process the images now... Must admit to rather enjoying getting some images of the planets

[Clayton]

It definitely looks better to me. But maybe back off ever so slightly with the deconvolution. It is very much a personal thing though, and tempting to tease out the detail, but quickly causes the loss of the natural look IMHO. I'm only quite new to these post stacking filters myself, so cannot be considered an expert in any sense.

[arad85]

Hi Clayton,

I was wondering that actually. It's a combination of 2 deconvs. One at about 8 pixels and the other about 16 - both put into the image using photoshops layer mask with a gradient filter from the centre. Also added an inverse brightness adjustment (so the outsides were adjusted more than the inside). Lots more processing - and lots more learning to do

Here's one with exactly the same processing, but less deconv (the 8 is still there, the 16 gone).

[Kokatha man]

That last one is the best processed imho Arad.....you've almost eliminated the ringing around the planet's periphery which can be instigated by a number of factors, but over-processing is the main culprit.....

I'm unfamiliar with the deconvolution methods and values in p/shop as I use AstraImage for that aspect of processing (after Registax) but ultimately you can't make a silk purse from whatever - meaning attempting to apply deconvolution to an image beyond its capabilities isn't worthwhile - which is why I rate that last one as the best of them, it isn't "pushed" too far!

You are doing very well and the progress is quite palpable.....if you can capture on a very good night you will not only get exponential improvement in the raw data but you'll find that processing becomes much more self-defining, in that it is easier, details will reveal themselves under lighter application of the various controls and you can much better make the judgements between "too much" and "just right".....the images will almost "self process" and in fact less will be best....!

[Clayton]

Nice work! The ring around the edge is not so pronounced.
I used another piece of software called "Astra Image" It took me a while to find the right version (3.0) as the early versions don't have deconvolution and some of the functions are crippled in later versions. Save is crippled in all of the versions so I just do a "Alt-Print Screen" and paste into Paint to save it as a bmp.
It's all a bit convoluted if you'll pardon the pun
But Astra Image has a simple interface and a nice preview function. I'm still a bit green working in CS3 with layers etc.
So I default to a formula I discovered on Forums, originally posted by Kokatha Man.
"After Registax processing, if you have AstraImage go to "Process" tab and do a Lucy Richardson deconvolution (usually around 3 iterations at a curve width of around 1.5) and then under the "Image" tab resize using "Mitchell" method to around 130% - 150%.....after this go back to L-R deconvolution and another 3 iterations at say 0.8 to 1.0 curve width.....just check with specific values for the aforesaid to maximise the image appearance/quality.....then it's on to P/shop for finishing where if you reduce size again at the finish (perhaps after a "smart sharpen" and "despeckle") it'll sharpen up everything a little more.....!"
I find If I do this I can back off on the Wavelets a bit in Registax
and I am still playing with it all to get a feel for it. And trying to get a new secondary mirror before Jupiter is too far gone

[Kokatha man]

.....my only proviso on what Rob's quoted of me is in my previous post - it is of no benefit to do a second L-R deconv. (or the resizing) unless your original image can carry it.....having a bigger image with bigger blurs isn't an improvement imho.

In fact ,far better in those circumstances to actually decrease your scale to sharpen any details present.....that quote, especially the resizing, was for images that could carry said; and was specifically for part of a regimen where the final image was downsized in CS3 to sharpen again.

Just to demonstrate, you might like to downscale one of your better processed larger images to see this sharpening.....

[resonator77]

Originally Posted by arad85

Hi Clayton,

I was wondering that actually. It's a combination of 2 deconvs. One at about 8 pixels and the other about 16 - both put into the image using photoshops layer mask with a gradient filter from the centre. Also added an inverse brightness adjustment (so the outsides were adjusted more than the inside). Lots more processing - and lots more learning to do

Here's one with exactly the same processing, but less deconv (the 8 is still there, the 16 gone).

Arad85,

are you a professional astronomer ?
by the looks of your signature you have got dozens of telescopes

[arad85]

Thanks for the help guys. The C9.25 is outside cooling again to see if I can capture another set. I'm starting to get the hang of the processing and using layers in Photoshop to apply different effects at different places in the image. I'm also going to order a tablet to make life a bit easier when processing in PS! I haven't got the LR deconv tool and I didn't try iteratively processing a small deblur - will give that a go next time (hopefully tonight )

@resonator... no, far from it. I have 3 telescopes.. a small one, a medium sized one and a big one

[Kokatha man]

Hi again arad - cooling down is a major "must do" with the SCT's (I have a C11) and the other major "must do" is make sure the collimation is the best you can do.....it is a process that takes time at the start of any session but is allways important to check.....although it seems to maintain collimation fairly well in the Celestrons unless something untowards happens: poor collimation results in "soft" ie blurred images.

Less bright stars (Mag. 2 or thereabouts) seem to work better than brighter ones with star-testing at high power on average nights (ie, poor seeing!) - it doesn't appear to create so much spurious and distracting effects around the star's image .....helping to sort the wheat from the chaff so to speak when getting to grips with this fine-tuning - and don't go out of focus too much 'cos it is actually harder to determine the concentricities. Imperative to get a good handle on collimation though with your SCT....!

Creating a duplicate layer is the way to go in P/shop when you make any new applications of the controls.....it just makes it easier to keep track of what you're doing and to easily "switch off" something you've just done to see if it really did improve the image.

And of course keep the "history" box open so that there is a record in front of you of what you've fiddled with....!

[arad85]

Hi Kokatha man,

Yup... I always try and nail both cooling down and collimation before starting. I have a lymax cat cooler which I use if the SCT hasn't been outside for a few hours and I always check collimation on a star before polar aligning. I agree about star testing on a slightly dimmer star, and I also agree (after seeing it myself last night) you only go a little out of focus. Whilst it is relatively easy to get concentric circles around the star, what is more difficult is to get the slightly out of focus rings to be evenly lit. I still haven't managed to get it 100% perfect yet - although I was pretty close on the 21st and last night.

I have a couple of sequences from last night that I'll process later today and post up. I'll also post up some stills from the video that generated them too, so you can see what sort of crud we have to deal with here

[Kokatha man]

.....hope there's no "trying to tell someone how to suck eggs here" A - and I do realise that the amount of "crud" and Joop's low elevation are real obstacles.....just thought I'd comment about the star -testing.....

Have you noticed the little pinpoint of light in the centre-region (dark spot) with the slightly out-of-focus star you're collimating on.....it's actually the Airy Disk you'd see if it was a perfect night or you were using an artificial star: when you pull out of focus slightly you can see it as a little pinprick of light, even when conditions are poor and you'd have no hope of seeing the proper Airy Disk at focus.

Getting that tiny pinprick central in the dark central area of the out-of-focus pattern is just about as good as getting evenly-illuminated rings around the Airy Disk.....

[arad85]

LOL... no problems.. You have to check everything - one item out of place and the whole thing is messed up.

Yup, the dot is fairly central (as central as I can tell with all the dancing going on around the outside )....