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gregbradley
19-08-2010, 01:59 PM
Here is the first of my images using this setup. It is also 2nd light for my new observatory.

I think this setup is a first for amateur astrophotography; 180mm of APO aperture, F5.25 and covering corner to corner of a 16803 chip with round stars. At least from what I have seen on the net. Usually maximum aperture for that would be TOA150 and reducer or AP155/160 and its reducer.

HaLRGB 70 70 60 70 for a total of 5:30 hours.

TEC180Fl F7, 4 inch Tak reducer (.75X) giving F5.25 (approx), FLI PL16803, Astrodon Gen 11 LRGB and 5nm Ha, Tak NJP mount.

http://www.pbase.com/gregbradley/image/127600632

Greg.

marco
19-08-2010, 02:40 PM
Interesting combination Greg, that OTA must be really awesome!

Did u see my pictures about the Pentax adapters?

Marco

AlexN
19-08-2010, 02:41 PM
Oh wow! 180mm F/5.25 flat field APO... Talk about a weapon! Thats gotta be the most wild imaging scope around these parts! :D

On to the pic! That is indeed stunning, If anything it could do with a touch more saturation (personal taste) but the field of view is amazingly good.. Its a massive field full of interesting bits and pieces... I dare say you can think of a million ways to exploit such a massive FOV

strongmanmike
19-08-2010, 02:52 PM
Well I have always imagined being rich enough to have a custom 12" F5 Petzval design Flourite APO built...this is getting close I guess? :P :thumbsup:

Nice work Greg

Mike

actually, you seem to have the means...have you considered looking into a custom 12" F5 Petzval APO..? :question: ;)

renormalised
19-08-2010, 03:13 PM
Nice shot there Greg. Colours are good and the stars seem very pinpoint and sharp. Good work:)

renormalised
19-08-2010, 03:14 PM
You mean, does Greg have a spare $200K:):P

gregbradley
19-08-2010, 06:00 PM
Yes I just saw that Marco. Very nice.

I'm going to get Ashley at Precise Parts to make me one. He must love me, I have a box full of his wonderful adapters.



I am in delicate saturation mode after super saturating my last image initially until Humi alerted me to it (thanks Humi).

What objects would you recommend?




Sounds like an awesome scope. What I have now I am happy with for some time (he says).



Thanks for that. I was happy the star sizes were smaller.



Tony Hallas had Roland Christen make a 206mm APO specially for him with super coatings. He has done some amazing images with that beauty.

Greg.

AlexN
19-08-2010, 06:41 PM
This time of year, the first target that comes to mind is the veil. With that massive fov and the sensitivity of the 16803, coupled with 180mm f/5.25, i think you could do some real damage in that area.. Ha+r - g - o3+b would be my plan.. But everyone is different...

M31 would be impressive in that setup too i think... You'd fit in almost the whole lmc or smc..

Lots of thoughts...

Bassnut
19-08-2010, 07:32 PM
Well, excellent full frame ofcourse, huge field, but still dont understand why you WFW guys dont seperately process objects, they are are a bit washed out with zooming on them.

multiweb
19-08-2010, 08:46 PM
Pretty cool. :thumbsup: I never noticed how the dust turns redder towards the bottom. Wide fields pick up a lot of variations you miss on narrow ones. Sorry Fred :P

Bassnut
19-08-2010, 08:49 PM
Dont appoligise on being wrong Marc, its OK, I understand :thumbsup:.

leon
19-08-2010, 08:50 PM
Nice one Greg, it seems very easy to look at very soft sort of image, and I don't mean that badly, well done indeed, and great colour.

Leon

Jen
19-08-2010, 11:37 PM
:eyepop: Wow very nice Greg :thumbsup::thumbsup: Very soft and beautiful color there ;)
Just gorgeous :)

avandonk
20-08-2010, 08:31 AM
If I was you Greg I would forget about taking HA and luminance data as it corrupts the real ratios of the RGB by modulating unrealistically. At f/10 with marginal detectors and tiny fields this is a reasonable protocol. At f/5.25 with an unobstructed near perfect optic and state of the art detector it holds back the real potential to show the full dynamic range.

Could you just show an image from the RGB data as I would think it would show far more realistic colours.

Colour does not exist! We perceive colour as the ratio's of the intensity of the 'R', 'G' & 'B' cones in our eyes. The sensation of colour is produced by the brain.

When you have this correct and have used the full dynamic range of your detector. Then collecting data at different exposure sets by doubling exposure levels to far exceed the dynamic range of your detector also would be worthwhile exploring. In other words HDR.

In my opinion we are only just seeing the start of the full potential of this setup.

There is far more that does not need to be gone into here. I would be willing to help in any way that suits you.

Here is an animated gif of your image and from my data from the Sagittarius mosaic. With longer exposures taken with your setup and HDR the dust would come up a treat. 6MB

http://d1355990.i49.quadrahosting.com.au/2010_08/gb02.gif

Your image is showing the faint blue reflection nebulae far better than I have ever seen.

Bert

Lester
20-08-2010, 09:53 AM
Top class image Greg, thanks for sharing it. I will look forward to many more super images from you set-up. All the best.

gregbradley
20-08-2010, 03:15 PM
I am not sure I can image that low over my observatory walls.

Any other ones in range?



Hey, who're you calling a WFW?? I started imaging at 2500mm + last night!!
There was a 1/3rd bright moon during this shot as well. But point taken. I could also registar in longer focal length detailed shots of the key objects. I've seen that done before and that can look good.







My images often have a hard look and I decided to keep it softer being a nebula. Just an opinion, but I think it is more pleasing that way.



Thanks Jen I am glad you liked it.




I would be interested in doing some HDR images. I see Photoshop CS5 has an improved HDR tool. So basically it is taking shorter exposures for the bright areas and longer exposures for the dim areas and blending them together with the Photoshop HDR system?

It is true straight RGB can be richer in colour but it also can lack vibrance and clarity which adds to the punch. But I will dig up straight RGB for it.



Thanks Lester.

I probably won't be imaging with it for a little bit as attention is now fully on the CDK17 which I started imaging with last night. Once I get autoguiding going I'll be imaging something. I suppose with the moon up it'll be something in Ha. I was getting 2-3 minute images with round stars at over 2500mm focal length and polar alignment not yet perfect.
Gotta love the PME even if it does make weird noises (it sounds like a fax machine sometimes).

It slews the CDK 17 around like its nothing. Faster than the Tak NJP. But the NJP has a sweet sound to its hand wound motors that spin at 19,000 RPM like a jet motor.

Greg.

Paul Haese
21-08-2010, 08:31 PM
Vast expanse of real estate Greg. The blend looks a little pink to me and even the stars have the appearance of being slightly pink.

That said the potential of this setup for wide field images is looking very nice indeed. Nice star sizes too.

David Fitz-Henr
21-08-2010, 11:38 PM
Beautiful wide field shot there Greg - stars look sharp across the HUGE field!! Colours look nice too! Not sure if they are too pink as noted - the whole area is bathed in nebulosity so maybe an accurate rendition ...

Tom Davis
22-08-2010, 02:55 AM
Wonderful image Greg and nice setup!

Tom