Posts Made By: Enrico Africa

January 24, 2005 01:03 AM Forum: CCD Imaging and Processing/Solar System

Veil Nebula HaRGB (NGC 6992)

Posted By Enrico Africa

Here is an H-alpha/RGB of the Veil Nebula (NGC 6992). The data for this was taken over two or three weeks last August, and after several long struggles with weird-shaped gradients, I finally have a version that is somewhat acceptable. There are still a few gradients here and there, but that will be for another day.

SBIG ST-8XE on a Borg 76ED @ f/6.6 on a Takahashi EM200 mount.

Ha: 13 x 15 minutes binned 1x1 (16 exposures, 3 rejected)
R: 9 x 10 minutes binned 1x1 (10 exposures, 1 rejected)
G: 9 x 10 minutes binned 1x1 (10 exposures, 1 rejected)
B: 9 x 10 minutes binned 1x2 (10 exposures, 1 rejected)

All images combined using Sigma Reject Beta 10 (rejected images identfied in this software). Images acquired with CCDSoft. RGB image combined in AIP4WIN using RGB weights provided by Don Goldman's RGB calculator.

Post-processing and HaRGB combine in Photoshop CS.

This was a first attempt at a 1x1 RGB. The RGB alone is pretty cool by itself. But I probably won't be trying that again for a while. The HaRGB combine does not look as deep as other HaRGB's I've seen, I'm not sure what went wrong, but it's still satisfactory. For now.

The image can be seen at http://members.nuvox.net/~on.aunt/DSO/VeilHaRGB.jpg

Thanks in advance for any comments or suggestions.
Eric


February 17, 2005 03:31 AM Forum: CCD Imaging and Processing/Deep Sky

My attempt at M81 and M82

Posted By Enrico Africa

Here's my attempt at this popular duo.

Imaged the nights of February 3 and 4 with my Takahashi FS102 at f/8 using an SBIG ST-8XE and the Astrodon Tru-Balance filters.

L: 19 x 10 minutes binned 1x1
R: 12 x 5 minutes binned 2x2
G: 12 x 5 minutes binned 2x2
B: 12 x 5 minutes binned 2x2

Feedback appreciated!
Eric

March 13, 2005 03:03 AM Forum: CCD Imaging and Processing/Deep Sky

Rosette Nebula

Posted By Enrico Africa

Last February 18th the sky was unexpectedly clear. The moon was also out, so I took advantage of the circumstances by shooting a Hydrogen-alpha image of the Rosette Nebula, one of the targets I had always wanted to image.

This was kind of a hurried shot, as I had this feeling I would only have one shot at imaging this object this season. So I took a few shortcuts: I binned my guide chip 2x2 (which a lot of the experts recommend anyway) for extra sensitivity, and used 10-second guide exposures (thank goodness for a great mount!), which helped me luck into a guide star. I normally try to dither my exposures, moving the guide star around every few exposures, but in my quest for going as long as I can in one night I decide to forego that.

As a possible result of those shortcuts, I lost a couple of exposures to weird tracking (no idea why, but the guider and mount seemed to recover anyway). I lost a couple more images as the Rosette set behind some trees. Ah, well.

In addition, on processing my image I found quite a smattering of dark pixels all over the image. This is either my dark library (I have over ten darks for this temp/exposure/bin setting, though), or a plain result of not dithering. So I had quite a bit of cleaning up in Photoshop, but I might still have missed a few. This, plus my relative lack of experience with processing H-alpha images, is the reason behind the delay of my post.

Details:
Scope: Borg 76ED f/6.6 (500mm focal length)
Mount: Takahashi EM200
Camera: SBIG ST-8XE with CFW-8a filter wheel and a Custom Scientific 4.5 nm H-alpha filter
Exposures: 10 x 15 minutes (2-1/2 hours total)

Images captured and calibrated in CCDSoft. DDP applied in MaximDL. Levels and curves applied in Photoshop. Noise reduction and smoothing applied with Noise Ninja.

Enjoy,
Eric

May 1, 2005 11:36 PM Forum: CCD Imaging and Processing/Deep Sky

Trio in Leo

Posted By Enrico Africa

Hi all,

Below is a link to my first attempt at the famous Trio in Leo, imaged the nights of March 31 and April 3, 2005.

Technical details:
Scope: Takahashi FS102 @ f/8
Camera: SBIG ST-8XE with CFW-8a filter wheel and Astrodon LRGB filters
Exposures:
L: 16 x 10 minutes (2 hours 40 minutes total) binned 1x1
R: 10 x 5 minutes binned 2x2
G: 10 x 5 minutes binned 2x2
B: 10 x 5 minutes binned 2x2

Images captured and calibrated in CCDSoft. RGB combine and gradient removal in MaximDL. Levels,curves and LRGB combine applied in Photoshop. Final processing done in Photoshop.

I had a heck of a time processing the background. As I was performing my LRGB combines, the background was getting splotchier and splotchier with conspicuous swirls of color. Darkening the background would only clip data. Even this attempt still led to clipped data.

Enjoy all!
Eric


May 14, 2005 04:38 PM Forum: Pictures of Me and My Telescope and........

Mew!

Posted By Enrico Africa

A slightly embellished tale: grin

I found this sitting in our front porch a few days ago, mewing for a new home. Recognizing it from pictures as once belonging to a fellow Astromarter who had given it up for adoption, I decided (with my wife's blessing) to take it in.

The following evening, it playfully climbed on top of my EM200 mount, eager to show me what it can do to make me keep it. It did get a little playful with me as I tried to balance it on the mount, but fortunately (other than the mount slipping in RA with clutches locked! 8O ) I did get it to balance.

It turned out to be slightly cross-eyed, but thanks to some Knobs installed by its former master, I was able to uncross them for the most part, and the views it gave me are most thrilling. Perhaps after some Fancy Feast it will stop Mewing and maybe some day start Meowing? 8)

Enjoy.
Eric

May 15, 2005 03:57 AM Forum: Takahashi

Re: My new Tak Rig

Posted By Enrico Africa

That's a sweet setup! I like your scope menagerie, too! grin

Eric

May 22, 2005 08:45 PM Forum: CCD Imaging and Processing/Deep Sky

M64

Posted By Enrico Africa

Here's a half-baked image that I originally had little hope for. I shot the luminance last May 4th with the intention of shooting the RGB's the following night. That following night, Murphy took over completely: I couldn't find the guide star I used the night before to gather luminance; after settling on another guide star (which positioned the galaxy in a very different part of the frame), everything went out of focus. I finally gave up and gathered luminance for another target.

Later that night, I discovered the reason I was having so much trouble: the compression ring holding the camera nosepiece was not snug: a slight twist, and the camera came off the scope! shocked After realizing that, I was thankful that nothing worse happened.

Anyway, I wasn't too excited about processing this, but a few days ago I decided to give it a shot. One glance at a calibrated raw frame had me gibbering in Huttese.

So, here's the processed luminance. I hope to have color some day.

14 x 10 minutes binned 1x1
SBIG ST-8XE
Celestron C8
Takahashi EM200
Astro-Physics 0.67 Telecompressor

Eric

June 26, 2005 12:00 AM Forum: CCD Imaging and Processing/Solar System

Jupiter 6/22

Posted By Enrico Africa

Hi all,

This might be my first post in this forum - I've been very focused on DSO CCD imaging over the past couple of years. I have kept an eye on solar system imaging, though, and played on and off for a few years with a SAC-IV with very limited success.

Anyway, after a Mewlon 210 showed up on my doorstep last month for adoption (Mew!), and with this year's Mars apparition coming up, I thought I'd exercise this aspect of imaging again (best part is, I don't need to be up all night capturing precious few photons!)

My SAC-IV decided to have a contest with my concrete patio (the patio won), so I thought I'd give the Celestron Neximage a shot. This image represents the best of about 100 frames from a 30-second video (lots of dropped frames - I need USB 2.0!) stacked and processed in Registax.

For Registax processing, I'm way low on the learning curve with that. For this image, I tried the approach of an aggressive setting on Wavelet 6 (about 60), half that in 5, half again in 4, etc.

Comments and processing tips appreciated.

Thanks,
Eric

July 14, 2005 02:40 AM Forum: CCD Imaging and Processing/Deep Sky

Mewlon won't come to focus with AP telecompressor!

Posted By Enrico Africa

So, were you expecting an out of focus image? grin

Seriously though, last Saturday was first CCD light for my new (to me) Mewlon 210. I was all set to go with it and an AP 0.67 telecompressor in a JMI NGF-S. The focuser configuration was nearly identical to one that worked on my C8: SCT back (adapter in the case of the Mewlon)/NGF-S adapter/NGF-S/2"-SCT adapter/AP SCT-2" adapter/Telecompressor/2" nosepiece/CFW-8a/ST-8XE. I needed more in-travel.... :S

At the urging of my imaging buddies (I was at a friend's dark sky site), I removed the telecompressor and attached the camera directly to the NGF-S via the 2" nosepiece. I did this with trepidation, as I was not confident about tracking/seeing at 2415mm focal length and f/11.5.

I guess I didn't need to be too concerned.

Yeah, it could use more tweaking, but hey, it's first light!

Takahashi Mewlon 210
ST-8XE
Takahashi EM200
4 x 10 minutes L binned 1x1

Subframes added, 2 iterations of L-R deconvolution in CCDSharp, levels, curves and cleanup in Photoshop CS. Cropped and resized in IrFanView.

I have not given up on the AP reducer yet - the NGF-S SCT-focuser adapter has a light shield that intrudes into the focuser drawtube. I just ordered a version that does not have the light shield. Hopefully this will give me the in-focus travel I need to achieve focus.

Comments? Suggestions (other than the obvious - more exposures!)?

Bigger image can be seen at http://members.nuvox.net/~on.aunt/DSO/M51Mewlon.jpg

CS,
Eric

July 18, 2005 02:48 AM Forum: CCD Imaging and Processing/Deep Sky

M64 from May

Posted By Enrico Africa

Here's a much-delayed M64 taken last May. Luminance data was capured May 4th and RGB data May 30th.

SBIG ST-8XE
CFW-8a with Astrodon LRGB filters
Celestron C8 OTA
Takahashi EM200 mount
AP 0.67 Telecompressor

L: 14 x 10 minutes binned 1x1
R: 6 x 5 minutes binned 2x2
G: 6 x 5 minutes binned 2x2
B: 6 x 5 minutes binned 2x2

Eric