M20 full Rez LX200R

[Striker]

This was my second target last night.

10 x 3 minute images at F10 2500mm FL with modded Canon 350D taken from my house Brisbane.

It looks like I will be imaging at F10 for a little while now until I can purchase a decent focal reducer.

Hutech light polution LPR filter used.

Would have liked to have got more images and longer exposures....tracking was acceptable....you can see some slightly oblong shapped stars but I am not after perfection...well yes I am but I am not going to say that...lol

Pretty happy with this one for just a quick target...will probably post another M20 later on with more data..hope you dont mind.

Full size version warning 1.2mb
http://www.users.on.net/~striker/M20full.jpg

[Astroman]

That looks great tony, slightly blown in the middle but doesnt make any difference the rest of it looks great right to the edges.

[h0ughy]

yep pretty average Tony! ;-)

[Striker]

Thanks Andrew and houghy(I think)...I havn't learnt the masking method..looks simple but I keep getting it wrong.

I may have to settle for large scale F10 imaging...it's not all bad
I just never wanted to image at that focal length because it was too hard...F6.3 1700mm is much easier but now the mounts performing much better what the hell...lets do it.

[Lester]

Very very nice Tony,

that 10" richy cirtainly keeps the star images down in size. Look forward to much more from you with that scope.

[EzyStyles]

that is a magnificant image tony. so sharpp and crisp.

[avandonk]

Looks like that RC is all its cracked up to be. Very good image! Were you autoguiding?
Bert

[Striker]

Yes Bert Autoguided through the Ed80 with Sbig ST-402XME using CCDSOFT.

[xelasnave]

As nice as I have seen anywhere. That is very close to perfect Tony it will be hard to beat. But no doubt you will.
alex

[davidpretorius]

awesome!

[RB]

That's a stunner of an image Tony, simply beautiful.

:)

[spearo]

Tony,
Very nice and sharp! Focus seems excellent too.
Just beautiful, well done indeed
frank

[tornado33]

In theory, nebula filters like the UHCS are more efficient at F10 as the cone of light is more parallel, and as the filter is an interference based filter, the passband will be more accurate, at very fast f ratios the light hits them at more of an angle, meaning they arent as efficient. Grab the UHCS filter and tilt it while looking through it in daytime, you will see the colour change.

Anyway your tracking is certainly handling F10 well. If you go 4 times longer (or 4 times as many subimages) you will still get same brightness as shooting normally at F5. E.g. shooting F5 for total of 15 mins, can shoot for 1 hour at F10 and get same intensity (but better images due to better filter efficiency)
Scott

[Striker]

Thanks Scott,

I am intersted on how the hutech LPR filter will perform now..I think I will get a much more natural colour now instead of over doing the red bias....we will see.

[h0ughy]

OK Tony, it is a very good image! there was no derogatory remark implied! could do with some more blue though.

[hevelsky]

Hi Tony,
Very good image !!!! Beautiful....;)

[alandee]

Stunning. Beautiful balance of colours.

[strongmanmike]

As I said on MMS this is a really good image and lends weight to the notion that the LX200R's might actually be quite good scopes...?

Great early image and we look forward to the images you will get once you have the new gear really honed in! :)

Mike

[iceman]

Wow Tony, I remember when you had an 8" dob :P I'll always be saying that :)

Incredible shot.

[avandonk]

Hi Tony took the liberty of running your image with Richarson Lucy enhancement with ImagesPlus. This would work much better with the original Tiff.
Here are two crops. Which is which?

[iceman]

the left one looks like the deconvoluted one, it's a bit sharper.

[RB]

I agree, the left one.
What settings did you use Bert?

[Striker]

Yes I say the left one Bert....looks sharper.

What setting did you use..havn't bothered with that function yet.

[avandonk]

I used 11X11 for ten cycles. It would most probably be different for the tiff. I would try 9x9 as well.
The good thing about RC telescopes is that the images they produce really only suffer from point spread function aberrations. That is Bessel Function due to diffraction. Gaussian is a good approximation for a Bessel Function at least for the zeroth order.

RC telescopes are as close to perfection as humans can make.

Tony's image tells you that with one look.

Bert

[Striker]

Whatever this means Bert we believe you......where's that dictionery....lol

Thanks for the processing tips....we are always learning...thanks.

[Striker]

Hey Bert...where would you start with noise thresshold under the same settings....looks like default is 2 parts from the left...leave it their or adjust it.???

[avandonk]

What that all means Tony that the original object ie a star is a point. When we image that point we get a diffraction pattern. If the aperture of the telescope is circular the diffraction pattern's intensity is in the form of a Bessel function. See pic below, recognize it?
Now all other points in an extended object (nebula) do exactly the same thing. Knowing this then the image we get can be deconvoluted to look more like the original. Because we know the mathematical relationships and with the power of modern digital computers,this is now a relatively simple exercise.
The planetary guys can get away with this with their Newtonians, as at the center of their optic the only aberration is diffraction. This is also why they collimate all the time! Further out they have coma due to spherical aberration.
RC optics don't suffer from this, a least over quite a good wide field.

Hope this makes sense. Just because I know a little (all right a lot) of science does not make me a teacher.

Bert

[avandonk]

Yes that means two sigma or twice the noise.

Bert

[Striker]

Thanks for taking the time explaining this Bert....it makes sence to me now.

Thanks for sharing this.

[avandonk]

I forgot to mention, that as the aperture gets bigger, the central peak gets bigger in relation to the other peaks. The central obstruction in most common SC's and RC's puts more intensity into the secondary and tertiary diffraction rings and so on. That is why the refractor officionados are so so vehement about their chosen optic.They just simply ignore chromatic aberration.

There is no perfect optic. You use the best one for the job.
My 300mm lens cannot resolve what your 2500mm RC can. Your 2500mm cannot show as wide a field as my 300mm lens. We all take our pick.

That is why there is no point argueing. Make the best of what you have and push it to the limits.

Scott is doing just that.

Bert

[davidpretorius]

Excellent Bert, that is brilliant. Thanks for clearing up a few things in my mind!

[avandonk]

What bit exactly? Please explain!

Bert

[davidpretorius]

the diffraction ring bit. what you have graphed is from side on, what we view as diffraction rings is from the top looking down.

therefore we need to correct those diffraction rings..

also the rc will have a more squashed up bessel function ie resolution is better, ie stars are tighter?

The penny seems to have dropped!

[acropolite]

Amazing image Tony, sharp and lots of detail, when did you say you were selling it???:P

[Doug]

Yeah, I'd say the one on the right is the original and the best; no dark rings around the foreground stars.;)
Just my opinion, and the original uncropped image is a beauty.

cheers,
Doug

[avandonk]

Doug they are jpg artefacts. Lets wait and see what Striker can do with the original tiff.

Bert

[Doug]

Hmmm jpeg artifacts?
here is a gif version sharpened with no dark halos. it is gif to get the file size down.
There werte no halos on the jpeg I downloaded from the supplied link.
Personally, I wouldn't want to sharpen an image as much as this, but for the sake of the exercise........................... .....
cheers,
Doug

[Shawn]

Fantastic Image Tony,,, Now I am even more keen to get my scope up and running,,,

[Shawn]

Im going to set that image as my desktop wallpaper, as a reminder to stop goofing off on the PC, and pull my finger and finish the observatory, cant see a lot thru my lounge roof, and I cant move the scope without 2 others assistance, :(.

[Striker]

Image done with Berts tips.

Adaptive Richardson-Lucy
Gaussin PSF size 9x9
Noise 2
10 iterations
Hope I did it right Bert.

http://www.users.on.net/~striker/M20-redone.jpg

[Doug]

Tony, which version do you like best? the original version or the latest version? Or to phrase it differently, if you were thinking of entering a competition, which image of the two would you submit?

cheers,
Doug

[Striker]

Hi Doug,

Imaging is a bit personal so what ever you like the best...I have noticed some like to push the image to get all the really faint stuff and destroy the best part of the image doing so...thats my opinion.

But if I had to choose I would pick the second image but their's not much in it.