Posts Made By: Enrico Africa

Last weekend, after shooting M51, I started imaging my intended primary target for the night, M27, the Dumbell nebula.

I decided to gather the RGB data first, realizing as I was starting at almost 3AM that with the depth of exposures I wanted to get, there was no way I was going to get all the data before daybreak. At the same time, I have yet to gather color data for this object, so I thought it was time.

One first for me was the use of the Color Sequence command/tab in CCDSoft to gather all the data for me while I took a nap. It was refreshing to start an imaging run, then go and take a nap. The only downside to this was that I would not be able to dither my images.

Anyway, I started my run and turned in for a nap. Two hours later, I got up (it was 5AM) and came out to ... clouds.

Bummed, I went to my scope to stop its imaging run, but found out that the guide star was still visible! There were two images left in the run, and I was tempted to shut down, but I thought let it finish, just in case.

The run ended, and as it was getting light I thought I'd try my hand at acquiring sky/twilight flats (this was at a friend's dark sky site, and I had forgotten my light box).

Today, I set about processing the image, and I am pleasantly surprised!

SBIG ST-8XE
CFW-8a with Astrodon LRGB filters
Takahashi Mewlon 210 OTA at f/11.5
Takahashi EM200 mount

RGB: 8 x 5 minutes each, binned 2x2

RGB combined in AIP4WIN. Artificial luminance composed of the RGB frames used to enhance features. Maybe some day I'll be able to gather some unbinned luminance of this object for details.

Thanks for looking,
Eric

VDB (Van den Berg) 142 is a dark/emission nebula that is a small part of the larger complex nebula IC 1396 in Cepheus.

Ever since I saw its haunting yet captivating shape, I knew that I wanted to image this object. From this perspective, it looks either like an Elephant Trunk, which it is sometimes referred as, or a gnarled tree root, or perhaps some mysterious hooded figure emerging from a mist. A Nazgul or Ring Wraith, from Lord of the Rings perhaps (http://www.alleycatscratch.com/lotr/Nasty/RingWraith.htm)?

Imaging details:
Takahashi FS102
Astro-Physics 0.67 Telecompressor
Takahashi EM200 mount
Imaging camera: SBIG ST-8XE
CFW-8a filter wheel with Custom Scientific H-alpha filter
Guide scope: Borg 76ED
Guide Camera: SBIG ST-7E
Robin Casady 14" Tandem Bar

8 x 20 minute images

Calibrated in CCDSoft
Combined in MaximDL
2 iterations of Lucy-Richardson deconvolution in CCDSharp
Levels and Curves in Photoshop CS

This is my first attempt at imaging with a separate guidescope. I can't say enough about the Robin Casady Tandem bar. There was no differential flexure visible at all. Narrowband imaging just became a lot more feasible for me.

A small image is attached. A bigger version can be found here: http://members.nuvox.net/~on.aunt/DSO/VDB142Big.jpg

Comments and suggestions welcome.
Thanks for looking!
Eric

Daddy longlegs on a bush. Captured in a camping trip at Jenny Jump state park in New Jersey over the 4th of July weekend. It was fascinating watching them walking around so gracefully on those long legs.

Olympus C-3040Z camera in macro mode. Automatic settings.

Enjoy,
Eric

Hi all,

Finally, an image to share (though I know I'd love to try and process it some more!).

Here's my take on NGC 7023, the Iris Nebula. Ever since I first saw this beauty, I knew I wanted to shoot it, as it is a blue nebula for a change.

Equipment:
Takahashi FS102
Takahashi EM200 mount
SBIG ST-8XE
CFW-8a filter wheel with Astrodon LRGB filters

Exposure details:
L: 31 x 10 minutes binned 1x1
R/G/B: 13 x 5 minutes binned 2x2

Comments, critics and suggestions welcome.
Thanks for looking!
Eric

Here's a pretty late for the season M13, shot last September 27th.

Takahashi FS102 @ f/8
Takahashi EM200 mount
SBIG ST-8XE
CFW-8a filter wheel with Astrodon LRGB filters
IDAS LPS Filter
Lumicon Minus-V filter
L: 8 x 5 minutes binned 1x1
R: 4 x 5 minutes binned 1x1
G: 4 x 5 minutes binned 1x1
B: 5 x 5 minutes binned 1x1

CCDSoft used for capture, MaximDL for calibration, registration and stacking. Photoshop CS for final processing.

A scaled-down full-sized image is attached. A full-sized crop can be seen at http://members.nuvox.net/~on.aunt/DSO/M13Crop.jpg

I can't seem to quite get the yellow stars out.

Comments and suggestions welcome.
Eric

All,

As a follow-up to my questions in a recent thread (the Horsehead taken with a Borg 77), here's my take on H-alpha imaging. I thought I'd try a totally different approach with my workflow, and when I compared the results with one done using the "Curves and Levels" approach of Photoshop, they were remarkably similar (even the shape of the histogram).

This is IC405, the Flaming Star nebula.

Imaged with a Borg 76ED on a Takahashi EM200 mount last October 29th.
SBIG ST-8XE
Cust-Sci 4.5 nm H-alpha filter
11 x 20 minute exposures binned 1x1

Processing flow:
In Maxim:
Median combine
DDP
Gamma stretch
High Pass filter restricted to brighter pixels Low Pass filter restricted to dimmer pixels

In Photoshop:
Some levels and curves
Noise Ninja
Gaussian blur to the whole image (0.5)
Further Gaussian blur to the grainier selection Dimming of the grainier selection Unsharp mask to the entire image

It's still dimmer than similar shots of this region I've seen taken with H-alpha, but pushing it any farther either brings out lots of grain, or the "graying effect" that I alluded to in my other post.

Anyway, comments and suggestions will be appreciated.
Eric

Hi all,

I haven't been imaging as much as I'd like, as I had set aside my faithful imaging companion (my FS102) in favor of a promised, sexier imaging companion. Well, that companion has so far not lived up to its promise. Its maker has promised that it will be repaired, but in the meantime I have reactivated my original companion. Thank goodness it is a most forgiving partner.

At the same time, I got meself some new gear to play with. Oddly enough, the curse of new equipment decided to let it slide and gave me a clear night to play with it. I mosied over to a friend's dark sky site a couple of nights ago.

I was almost foiled by focus issues (as in, I needed extensions!). Fortunately, we were able to rig a setup that enabled me to get into focus.

Here is M42 in narrowband

SII/Ha/OIII
Trapezium exposures: 3 x 1 minute through each filter
Outer regions: 4 x 5 minutes through each filter
Takahashi FS102 on an EM200 mount
SBIG STL-6303 with Astrodon Ha/SII/OIII filters (first light!)

Captured, calibrated and combined in MaximDL. Processed in Photoshop CS.

For whatever reason, IrFanView does not do the colors of this justice. A full-sized crop with better showing of the color can be seen here:

http://members.nuvox.net/~on.aunt/DSO/M42Narrow.jpg

Enjoy,
Eric

I still consider this a work in progress.....

Here's a 2-hour H-alpha of the Horsehead region. It's probably not obvious unless you blow it up (way up!), but there's some field curvature visible in the stars towards the corners - the reducer I'm using is likely not at its optimal distance, but this is not my long-term configuration anyhow...

Takahashi FS102 with f/5.9 reducer
SBIG STL-6303
Astrodon 6nm H-alpha filter
4 x 30 minute subs
Reduced in size by about 1/3

I stretched it a bit to show that the nebulosity that's not usually obvious below the HH region is beginning to show up. But that's for another time....

Eric

Hello all,

I rarely post here, since I normally do DSO imaging, but this is a solar system object

Comet Pojmanski was discovered just this past January. It is making its way north, and is now visible in the pre-twilight morning hours. I just found this out last Thursday or Friday.

Last Saturday night was clear in our part of the world. I joined a friend at his dark sky site to finish gathering data on a couple of project images I'm working on. My primary objective for the evening was to gather some blue data for a couple of narrow-band images that I am working on where the targets turned out to have little to no O-III emissions. My friend had also indicated that he may want to use my camera for some additional emission-line information for one of his targets, but he ended up shooting other targets instead. As we discussed possible targets, he mentioned the supernova in M100, and then almost as an afterthought he brought up the comet.

This is the beginning of galaxy season, and I was hoping to use a hi-res setup for some close-ups of galaxies (I wanted to say "nice close-ups", but I never know how my data will turn out). But I wanted the blue data for my emission-line objects, and brought my wide-field setup instead (can't easily fit more than one scope in my car). I guess I ended up having the right equipment for the comet!

http://members.nuvox.net/~on.aunt/Comets/Pojmanski.jpg

This is a crop of the full frame. I've been trying to combine a nicely-combined comet image with one having untrailed stars, but so far I can't seem to get it done without the final result looking "fake" - the trails around the comet are still visible.

Given the excitement around the comet, I thought I'd share my first (and probably only) shot of this comet.

This is a median combine of 12 or so images. I was guiding on a star, but aligned on the comet's head during the combine, which resulted in the trailed stars. The median combine did a nice job of reducing the star trails but obviously did not eliminate them.

Hopefully I'll have a better version with untrailed stars posted. I just thought I'd share what it looked like on Sunday, Feb 26 at around 11AM UT.

Taken with was a Takahashi FS102 operating at around f/5.9 with a dedicated f/5.9 reducer. Camera is an SBIG STL-6303. The FOV of this combo is 105 by 158 arc-minutes (around 1-2/3 x 2.5 degrees, if my math is right, and based on Ron Wodaski's CCD calculator). With the framing I had, the comet stretched about 2/3 of the way along the chip's narrower frame. That makes the tail visible from this image around a degree or longer.

Enjoy,
Eric

As we Earth-based gazers stare up at the heavens, we oftentimes relate the various objects we see to familiar-looking terrestrial objects or themes in our efforts to describe what we are seeing either through the eyepiece or on photographic plates or digital images. We name some objects based on their resemblance to familiar objects. Names such as the Rosette Nebula, the Running Man, the Christmas tree cluster, and the Pelican Nebula come to mind, not to mention famous familar shapes like the Horsehead Nebula.

Some objects are named differently based by different cultures. A famous (at least to me) example is Carl Sagan's presentation on Cosmos of how the Big Dipper asterism is referred to as the Plowshare in old England and (pretty creatively) as a bureaucrat being petititioned by the ancient Chinese.

There are some objects that have been given geographic monikers by obvious resemblances - the North America nebula comes to mind.

As I look upon images posted by other astro-imagers, I often find myself playing that Rorshackian (sp?) game of "what do you see?" Not unlike children lying in a field idly calling out what they see in clouds overhead, I ask myself to connect the dots in star clusters or find a shape in a nebula.

As I work through a small backlog of image data collected since January this year, I'd like to present an image that invokes a geographic moniker influenced by a cultural view. There is a dark nebulosity in Monoceros not too far from the Cone Nebula/Fox Fur region in Monoceros. I was not aware of this nebula myself until a year ago, when I was admiring an extreme wide-field narrow-band image of the region by a fellow imager. I resolved to shoot this interesting (at least to me) target.

It is an often-overlooked nebula, overshadowed by the aforementioned more-glamorous Cone and FoxFur nebula. It ofen shows up in images of the region, but is usually presented as a mere afterthought. I believe it is a part of the B36-37-38 dark nebulosity in Monoceros. It may have already been named, but if so I am not aware of any. I thought I'd showcase this nebula as the subject of interest instead as a tribute to my geo-cultural origin.

Without further adieu, may I present to you all what I would like to propose (at least informally) calling the "Philippine Nebula":

http://members.nuvox.net/~on.aunt/DSO/PhilippineNebula.jpg

To my Philippine-colored cultural eyes, when I first saw this nebula it really reminded me of a map of the Philippines, down to the neighboring Indonesian island of Borneo off the tip of the long island Palawan: http://www.gov.ph/aboutphil/philmap.asp With a bit of creative license, I oriented the nebula to match the orientation of the Philippines as laid out in the map.

The above image is a crop of the full-sized image available here:

http://members.nuvox.net/~on.aunt/DSO/MonocerosNebulosity.jpg

This was imaged February 18th with an SBIG STL-6303 camera using an Astrodon 6nm H-alpha filter through a Takahashi FS-102 refractor with a Takahashi f/5.9 reducer. This is a median combine of 5 30-minute exposures. I deliberately oriented my image to place the subject of this image in center stage. I could have framed it so that the Cone Nebula would have fit in the FOV of my optics, but I've been having a lot of misshaped stars in the corners either due to field curvature or a less-than-optimal metal back distance with the reducer used. Surprisingly, the stars seem well-behaved in this image.

Enjoy,
Eric