Images from 21 February

[Paul Haese]

Got down to the observatory over the weekend and imaged the following images:

NGC5128
NGC3579

Both images are deep runs of 25 minute subs. Data is contained on the bottom of each page.

Comments are most welcome as well as criticism.

[h0ughy (David)]

Hi Paul,

i like the result you were able to get with Cent A - after seeing Mike Sidonio's effort on this and comparing yours, you managed to get a nice result.

[strongmanmike (Michael)]

is...that.....Centaurus A????? Nooooooooooooo....

Sorry, Super images Paul, you have to be happy with these.

Looks like you have the guiding working but you are braver than I going 25min, I wouldn't trust everything to go right and would be too frustrated if I lost a few subs at 25min each

Not sure you could make any meaningful improvements to these? excellent mate!

Mike

[renormalised (Carl)]

Nice piccies, both of them. Good effort, Paul!!

[Tilt (Michael)]

Big subs! Nice results, good detail in both images.

Michael

[strongmanmike (Michael)]

Originally Posted by h0ughy

Hi Paul,

i like the result you were able to get with Cent A - after seeing Mike Sidonio's effort on this and comparing yours, you managed to get a nice result.

Yeh and just wait till you see them both on a decent monitor ....

[h0ughy (David)]

Originally Posted by strongmanmike

Yeh and just wait till you see them both on a decent monitor ....

I have actually gone through and readjusted the TV - lowering the contrast significantly and adjusting the brightness - then re calibrated. I was within 3% of the target output on both black and white which was a lot better than before (it changed to 200% on white and 60% on black and the sharpness module in the TV was set incorrectly when you were here , but i have learned that the tele has a user setting - which i adjusted) Now Mr Sidonio your Cirrus looks superb, your pinkish bits in the lagoon look superb, even showing different star colours blues, yellows , orange ones. your CG4 shot shows colours within the dirt LOL, and omega cent shows the star colours in the group - even the witch head look great. So nnaarrr SNOT perfect like on yours but its good

[strongmanmike (Michael)]

Originally Posted by h0ughy

I have actually gone through and readjusted the TV - lowering the contrast significantly and adjusting the brightness - then re calibrated. I was within 3% of the target output on both black and white which was a lot better than before (it changed to 200% on white and 60% on black and the sharpness module in the TV was set incorrectly when you were here , but i have learned that the tele has a user setting - which i adjusted) Now Mr Sidonio your Cirrus looks superb, your pinkish bits in the lagoon look superb, even showing different star colours blues, yellows , orange ones. your CG4 shot shows colours within the dirt LOL, and omega cent shows the star colours in the group - even the witch head look great. So nnaarrr SNOT perfect like on yours but its good

So what all this means Paul is that Houghy "would" have seen your images as gastly but now they must look good, Houghy was previosuly looking at images and thinking Oooh nice when in fact they were crapola but he had nothing to compare with so he didn't know any different, now he knows, bit like needing glasses and not knowing it until one day you get a pair and cripes ...

[Quark (Trevor)]

Very nice images Paul.

As a comparison I am comparing these two images to David Malins published in his most excellent book "The Invisible Universe", published in 1999.

Your images demonstrate just how far amateur equipment has advanced over the last 10 years.

I think your image of Cent A is exceptional, it reveals a great amount of quite delicate structure in the dust lane. It loses very little in comparison to the photographic plate of Davids.

When I first looked at your image of 3579 a rather elongated star within a tight loop of nebulosity toward the bottom of the main part of the nebula and to the left of centre caught my eye. This is actually two stars that appear in Davids image with clear separation. I realize that there is no comparison between the AAT and a Takahashi refractor but the detail that you have captured, albeit on a smaller scale is very impressive when compared to the images in Davids book.

Regards
Trevor

[dcalleja]

Brilliant images. Outstanding detail.

[Paul Haese]

Thank you all for the comments.

Mike you are a funny man.

Trevor, I constantly marvel at how far all amateurs have come in the last 5 years; let alone the last 10. Equipment and careful attention to details is what drives most of us. Personally, everytime I fire up the scope I just try for more detail, sharper images and better processing. I find that comparing images of many other people helps with the colouring of these images. The main thing for me is that this is all fun. I like imaging in varying capacities, but it has to be good fun.

For guys wanting to know how to get better images, I work on this policy. Not saying my images are better than anyone elses (in fact they are in many ways not great). However, I try to take as many deep subs on one target as will allow. Images get really smooth after 10 or so subs. Lots of darks are also important especially this time of the year. And; more importantly I have found that going more than 10 minutes produces very good signal which when combined with the numbers of subs cancels noise quickly. I gather this is somewhat the same for the true astro cameras too. For DSLR's though I stick to this rule.

Thanks once again.

[spearo (Frank)]

Great shots both of them especially Cen A awesome!
frank

[leinad (Dan)]

Fantastic Paul!!; thanks for sharing your advice on technique also.

Can I ask at what ISO level you took these long subs?

Did you also use a time delay between exposures? I was wondering how the DSLR performed with heat/time x exposure from one to the next , inc darks.

[bloodhound31]

I am a big fan of Centaurus A mate. Beaut job. So sharp, well focused and realistic.

Champion effort mate.

Baz.

[Paul Haese]

leinad,

I sue ISO800 and with an interval of 8 seconds between images. Unfortunate what I think you are looking for is someones experiences with an uncooled 40D or similar camera. My camera has been modified by Central DS with a peltier cooling unit. The chip is usually around 19 degrees below ambient and as such has little if any noise. I cannot really help you with an uncooled unit on such long subs. Although one of the other chaps that was there last night was using such a camera and doing 30 minute subs. He had prepared his darks the night before and just applied them when processing. So you can take long subs with an unmodded camera, but lots of darks are necessary to remove the noise.

[jase (Jason)]

Both very spectacular images Paul. No arguments from me about going deep. No reducer on the 102? Imaging at F/8? My only comment is that I'd like to see a little more blue coming out of those stars. Spec class M stars are looking good, but the O and B type could do with some more saturation I feel. Great details on display, quite a visual pleasure that sets the scene for DSLR imaging. Well done.

[prokyon (Werner Probst)]

Great pics!!!

[Paul Haese]

Thanks Jase,

No reducer but I have a flattener. Can you tell me how to bring out the saturation in those star types. Always more to learn.

[Octane (Humayun)]

Paul,

Fantastic work.

That is a magnificent Centaurus A. Kudos to you for keeping the background nice and even. Wonderful star colours and excellent guiding.

Regards,
Humayun

[Omaroo (Chris Malikoff)]

Very nice indeed Paul! As previously mentioned - a textbook effort.