Category Nebula

Apogee Ascent A694 – Post Repair Evaluation

Apogee A694 Evaluation – Before Repair

I purchased one of the first Apogee Ascent A694 Cameras (Sony ICX694 Chip) before the acquisition by Andor and had some random horizontal banding across the top of the frame that was not possible to calibrate out:

Random Horizontal Banding: Pre-Repair

Andor issued an RMA and took care of the costs under warranty.  They stated that they repaired the camera by replacing the whole electronics board.

Apogee A694 Evaluation – Post Repair

 

I was hoping to not see the random horizontal bands again but upon firing up the camera and cooling down to -15C there were still there although they are now contained in a smaller region closer to the top of the frame.  It still moves around so calibration is difficult if not impossible.  When using a small number of frames it is hard to statistically reject the band.  You can see below in M42, reproduced at 50% size, that a bright band stands out across the top of the bias and dark calibrated image even after calibration.  This is especially obvious in narrowband images where the background pixel count isn’t much higher than the bias floor.  The band is also visible across the bottom of the Horse Head shot (I flipped the image) although it doesn’t stand out quite as much.

For a low bias noise camera geared towards narrowband imaging that I plan to use for portable imaging (lower frame count) I don’t think that my options are too great:

  1. Cropping out the top part of the frame (It’s a small chip to begin with)
  2. Trying to fix it in post processing (Different for every image)

 

I am also including 100% size images of the bias, master bias, dark, and master darks used to calibration the two trial images.

 

M42-Stacked
Apogee Ascent A694 – 6x10min Ha Evaluation after Repair.

 

Stacked-Horse-Head
Apogee Ascent A694 6x20min Post Repair Evaluation

 

 

 

Here is what several bias frames look like animated to give you an idea how the horizontal banding moves around and therefore is not well calibrated:

A694-Bias-animation

This is certainly better than what it was before but I am still left with these bands appearing faintly in my images.

All images were captured with the CCD cooled to -15C.  They were captured with MaximDL 5 and calibrated / processed in Pixinsight.

Cygnus Mosaic – Hydrogen Alpha Emission

I began work on a tri-color Hubble Pallet image during the summer of 2014 but due to weather and other obligations did not capture much in the way of Oxygen [O III] and Sulfur [S II] emission data for the mosaic project so am leaving it as a monochrome image using only the Hydrogen Alpha emission line data.

Cygnus Mosaic in Hydrogen Alpha Emission Line FSQ-106ED Apogee U16 CCD Baader 7nm Ha Filter AP900GTO Mount 6x20min Exposure Campmeeting Observatory, Sewickley, PA
Cygnus Mosaic in Hydrogen Alpha Emission Line
FSQ-106ED
Apogee U16 CCD
Baader 7nm Ha Filter
AP900GTO Mount
6x20min Exposure
Campmeeting Observatory, Sewickley, PA
Cygnus Mosaic – Annotated

Cherry Springs 8/25/2014

Cherry Springs panorama from the northern side of the overnight astronomy field
Cherry Springs panorama from the northern side of the overnight astronomy field

 

Cherry Springs
Cherry Springs

Monday night was my first visit to a dark site; or at least my first visit since catching the astronomy bug.  Upon arriving at Cherry Springs after the 4 hour drive I noticed there were quite a few people  still hanging around after the Black Forest Star Party which was held over the weekend.  According to some of the other amateur astronomers, the weekend star party was a bust.

We found a vacant spot to setup our tents right next to one of the RV style power outlet posts scattered throughout the observing fields.  I can’t stress how wonderful it is to have power provided  on the field for the astrophotographically inclined!

The grounds were well kept and the main bathrooms much nicer than expected.  The surrounding area is gorgeous for anyone who enjoys the outdoors.

 

Untracked 30 Second Exposure
Untracked 30 Second Exposure

As nice as the park was, the show obviously didn’t start until the sun went down.  The Milky Way was more prominent before astronomical twilight than I’m used to seeing here in the PGH region after astronomical twilight; even at the Greene County site.  By 10:00pm it was gorgeous and I snapped a quick 3o second shot on a tripod and marveled that the dark lanes extending out from the Rho Ophiuchi / Antares region were clearly visible in a short exposure so close to the horizon.

Seeing the sky like this puts everything in a different perspective.

Yes, it’s depressing being back in light polluted Pittsburgh but I’m really glad I finally made it out to Cherry Springs after all this time.

I had plans to shoot some other objects but due to poor planning and setup of my tent I couldn’t take some of the deep southern objects I was hoping for.  I settled for 5.5 hours of exposure time on NGC 7023:  The Iris Nebula.  I have shot the Iris before but was never totally happy.  I’m still not quite satisfied but it’s certainly better than what I’ve gotten around here.

4 minute Exposure Canon 6D 200mm f/2.8 Tracking, Unguided
4 minute Exposure
Canon 6D
200mm f/2.8
Tracking, Unguided
NGC-7023-LRGB-Combine-V2
NGC 7023 Atlas EQ-G Mount Stellarvue SVQ100 – 100mm f/5.8 Quadruplet Apogee Ascent A694 CCD 5.5 Hours Total LRGB Exposure

 

The Iris Nebula, also NGC 7023 and Caldwell 4, is a bright reflection nebula and Caldwell object in the constellation Cepheus. NGC 7023 is actually the cluster within the nebula, LBN 487, and the nebula is lit by a magnitude +7 star, SAO 19158.[1] It shines at magnitude +6.8. It is located near the Mira-type variable star T Cephei, and near the bright magnitude +3.23 variable star Beta Cephei (Alphirk). It lies 1,300 light-years away and is six light-years across.[2]

Courtesy of Wikipedia.

Reflection Nebula NGC 6914 in Cygnus

Another decent night at the AAAP Greene County Dark Sky Site.

NGC 6914 is a reflection nebula nestled amongst the diffuse emission nebula in Cygnus.

NGC 6914 SVQ-100 Apogee Ascent A694 Atlas EQ-G w/eqmod 5x10min Lum 6x10min Red 6x10min Green 6x10min Blue Total: 3.8 Hours Greene County, PA
NGC 6914
SVQ-100
Apogee Ascent A694
Atlas EQ-G w/eqmod
5x10min Lum
6x10min Red
6x10min Green
6x10min Blue
Total: 3.8 Hours
Greene County, PA

Playing around with an 8mm circular fisheye lens as well for an all sky timelapse.

[youtube:http://youtu.be/l92QPyDS_GQ]

M20 – The Triffid Nebula

M20 - The Triffid SVQ-100 Quadruplet Astrograph Apogee Ascent A694 CCD Baader LRGB Filters Atlas EQ6 w/ EQMOD Greene County PA
M20 – The Triffid
SVQ-100 Quadruplet Astrograph
Apogee Ascent A694 CCD
Baader LRGB Filters
Atlas EQ6 w/ EQMOD
11x10min Lum, 4x10min Red, 3x10min Green, 3x10min Blue
Total Expose 3.5 Hours
Greene County PA

 

Imaging M20 through the light pollution.
Imaging M20 through the light pollution.

 

 

 

Hydrogen Alpha Mosaic – Test Framing w/ the Moon for scale

It’s that time of year when Cygnus rises high over head and displays a multitude of nebulous treasure.  This mosaic is only a portion of the Cygnus constellation but represents a large patch of sky almost 9 x 9 degrees.  This is only a test framing as I create a game plan for a summer long imaging project.  For a sense of scale, I have included a gibbous moon which was not part of the original image as well as a full scale crop of the Crescent Nebula, bottom right, to show the full size scale of the original 83 megapixel image.

Mosaic_12
Cygnus Mosaic in Hydrogen Alpha FSQ-106ED Apogee U16 AP900GTO Baader Ha Narrowband Filter 9x20min total exposure

 

 

IC 1848 – Open Cluster in the Soul Nebula

 

Full-IC-1848-100P

Full_IC_1848_100P_Annotated

IC-1848-Crop-4

IC-1848-Crop-3

IC-1848-Crop-2

IC-1848-Crop-1

And to put it into a little broader perspective here’s a wider field view which starts to show the Heart Nebula.

IC-1848-Wide

 IC-1848-Animation

Mount: AP900GTO3
Scope: Tak FSQ-106ED
CCD: Apogee Alta U16
Filters: Baader Ha, O[III], S[II]
MMOAG OAG w/ sbig st-i guider
Total Exposure 5 hours

A different Crop

I thought it would be fun to take an older image, reprocess it, and crop into smaller sections that would put a new spin on a very commonly imaged object. Hope you like them.  I won’t reveal what the object is until later.

MIXSHO_AIP_ABE-2

MIXSHO_AIP_ABE-3

IC 1396 – The Elephants Trunk

FSQ-106ED
Apogee U16
AP900GTO Mount
MMOAG w/ ST-402
9.5 Hours Total Exposure
Baader Ha, O[III], S[II] filters

The Elephant’s Trunk nebula is a concentration of interstellar gas and dust within the much larger ionized gas region IC 1396 located in the constellation Cepheus about 2,400 light years away from Earth.[1] The piece of the nebula shown here is the dark, dense globule IC 1396A; it is commonly called the Elephant’s Trunk nebula because of its appearance at visible light wavelengths, where there is a dark patch with a bright, sinuous rim. The bright rim is the surface of the dense cloud that is being illuminated and ionized by a very bright, massive star that is just to the west of IC 1396A. (In the Figure above, the massive star is just to the left of the edge of the image.) The entire IC 1396 region is ionized by the massive star, except for dense globules that can protect themselves from the star’s harsh ultraviolet rays.

The Elephant’s Trunk nebula is now thought to be a site of star formation, containing several very young (less than 100,000 yr) stars that were discovered in infrared images in 2003. Two older (but still young, a couple of million years, by the standards of stars, which live for billions of years) stars are present in a small, circular cavity in the head of the globule. Winds from these young stars may have emptied the cavity.

The combined action of the light from the massive star ionizing and compressing the rim of the cloud, and the wind from the young stars shifting gas from the center outward lead to very high compression in the Elephant’s Trunk nebula. This pressure has triggered the current generation of protostars.[2]

 

Description courtesy of Wikipedia