Thursday, July 30, 2020

Comet NEOWISE fading fast

I setup for imaging NEOWISE from my home site on July 26 and the 27th.  Placed my Canon50D piggyback on the GT102 with my Canon 100mm lens. Little did I know that my focus (on both nights) wasn't set properly and so both sets of subs were very sub-par.  After trying to process them multiple times the results were just not worth the effort.  I realized later that the focus ring on my Canon lens is so loose that it can rotate out of focus really easy.  Should have taped it down or used my Tamron which is much stiffer in that respect.

With the moon reaching full phase this weekend, the skies will be awash with moonlight. Once the moon reaches a point where it doesn't rise until after NEOWISE sets the comet will have dimmed to the point where the tail is significantly reduced in size and brightness.  So it's goodbye to comet NEOWISE.  Now I'll be waiting for the next bright comet to favor our skies.

Sunday, July 26, 2020

NEOWISE from Mikey's Place

Finally, NEOWISE is high enough that I can capture it from my home with the large telescope mount.  The sky wasn't very good though, lots of thin cirrus clouds.  But I decided to image the comet anyway.

Didn't have time to process the stacked images, but here is a single sub from my Canon50D with 100mm lens piggybacked on my GT102 and AP1100 mount.

Once the subs are processed I'll post the results here.

Comet NEOWISE
July 26, 2020 - Canon 50D/ 100mm f/3.5 60 sec ISO800

Friday, July 24, 2020

Comet NEOWISE - Close Up (Update)

Well, I took another shot at getting a better image.  Processed the 22 x 30sec images taken around 9:45PM.  Since there were more subs the noise was reduced a bit and I got some of the color as well.

Comet NEOWISE - July 18, 2020 9:45 PM
GT102 APO f/5.5  -  Canon 50D  -  22x30 sec ISO800

Comet NEOWISE - Close up

On July 18, 2020, the skies were rather clear and I decided to return to my church's property with my portable telescope setup (William Optics GT-102 APO, iOptron iEQ30 mount, Canon 50D).

I wanted to get some longer exposure images of the comet with a close up on the head and so the GT102 seemed like a good bet.  I realized that I would not be getting a lot of the tail(s). 

After spending about a hour and a half, 212 images later, and lots of processing time at home, I did manage a fairly good close up of NEOWISE.  I am a little disappointed that the image showed very little color.  The green coma was visible, but the final image didn't show it.  The sky conditions were not good enough to capture the ion tail in it's full glory, but I was also disappointed in that I really couldn't pull enough detail out of it as well - also devoid of any color.  Not sure if this is due to processing issues, or sky conditions.  Anyway, here it is.

Comet NEOWISE - July 18, 2020 - ~10:08 PM
GT102 APO f/5.5  - Canon 50D - 10x60sec subs - ISO800


Once the comet gets a little higher in the sky I'll image it once again at home with both my 11" EdgeHD and a piggyback Canon with 100mm lens.  That is if the clouds go away!  Each day that goes by the comet is getting dimmer, and, there are some reports (still unverified) that the nucleus may be starting to disintegrate.  Let's hope not.

Thursday, July 16, 2020

Comet NEOWISE at night

On July 15th I arrived at CrossLife Bible Church, Westminster MD, my home church, for our normal prayer group meeting at 6:30 PM.  The service ended at 7:30 and I noticed that the skies were somewhat clearing up toward the north/northwest.  We have a clear view in the direction where NEOWISE would be and so after dropping my wife back home I returned to the church property and setup my camera.

It was 8:40 when I arrived and got setup. There was still a lot of high cirrus clouds covering the sky where NEOWISE is located. I looked for the comet from about 8:50 to about 9:41 and nothing, not with the naked eye, not with 10x50 binoculars. Then, at 9:45, I spotted it! Shinning through the thin clouds it was still a splendid sight.

Comet NEOWISE, July 15, 2020 10:06 PM
18mm, f/5.6, ISO 1600 15x5 sec


It was about 74 degrees, with a strong wind (it's always windy at the church since we sit at the top of a hill and for some reason all the air rushes right over our site). I knew I would lose some shots just due to the camera being buffeted by wind gusts over 20mph. But my patience paid off.

I took 118 images, and processed four different sets. One of those sets produced a fairly good image of NEOWISE even considering the image was shot through a layer of clouds.

Comet NEOWISE, July 15, 2020 10:08PM
270mm, f/6.3, ISO1600 10x5sec


This image of NEOWISE was taken at 10:08 PM with a Canon 70D and Tamron 18-270mm lens. The lens was set at the full 270mm focal length and aperture at f/6.3. I took 21 subs, of which I used 10 in the final stack. Each was taken with an ISO of 1600, exposure time of 5 seconds. The subs were pre-processed and stacked with Nebulosity 4.0, and the stacked image further processed in PixInsight and Paint Shop Pro. I did take darks to limit the sensor noise and hot pixels, but Nebulosity didn't do such a good job removing the pixels. You can see them in a zoomed-in version of the photo as streaks of colored dots.

Now that the weather is not looking so good for the next week or so, it looks like the next photo opportunity will be at my home with the WO-GT102 telescope on my AP1100GTO mount. The comet will likely fade a bit by then (it is moving quickly away from the sun) but it will be much higher in a darker sky, and finally high enough to clear my tree line.


Thursday, July 9, 2020

First Images of Comet NEOWISE

Early this morning I was able to capture some initial images of C/2020 F3 NEOWISE.  I had provided some charts in my previous post and with NEOWISE only getting about 10 degrees up in the NE there was no chance I could image it from my home. So I packed up my Canon 70D and headed to my church property in Westminster. I decided against bringing my portable telescope figuring I try with just the Canon on a tripod and see what I could get.

The first photo is a composite (stacked) image of 10, 2sec exposures, at a high ISO value of 3200. The Tamron 18x270 lens was set to 77mm (I had wanted 100x but somehow the zoom slipped) at f/5.6.

C/2020 F3 NEOWISE, July 9 2020, 4:54 AM
Canon 70D, 77mm, f/5.6, ISO 3200, 10x2 sec


The second is a composite of 10, 1 sec exposures at ISO 1600, 270mm, f/6.3.  Since these exposures were taken rather late, the sky had brightened considerably. Lens fogging didn't help either!

C/2020 F3 NEOWISE, July 9, 2020, 5:06 AM
Canon 70D, 270mm, f/6.3, ISO 1600, 10x1 sec


Neither set of images were processed to eliminate/minimize noise, so they are a bit noisy.

Plan is to take a few more later this week, potentially Saturday morning, weather permitting.  Then, when NEOWISE makes it to the evening skies, I'll image with the either the GT102 or the EdgeHD11.


Sunday, July 5, 2020

Comet C/2020 F3 (NEOWISE)

Well, surprise, surprise ... one of the newly discovered comets might actually be visible and is not breaking up.  With the demise of ATLAS and SWAN I was hesitant to report on any hope of sighting a comet with the naked eye anytime this year.

But, NEOWISE is still going strong and is now positioned for the northern hemisphere.

If you want to see NEOWISE you have two choices.  Early in the morning, before sunrise or (later in the month) just after sunset.  It is probably the brightest right now and will be dimming slowly over the next two weeks so catching it in the AM might be worth the early rise from bed.  For those who prefer their sleep, it will be visible in the NW after sundown, and will be rising higher and higher in the sky (important if you are viewing from a location with lots of trees - like at my observatory.)

The two charts below will give you a rough idea of where to look for the comet.  Each one is fixed at a particular time (roughly with the sun about 10 degrees below the horizon) and shows the position of the comet on each day from July 6th through the 25th.

Comet NEOWISE - Morning
Reisterstown, Maryland


NEOWISE doesn't rise very high in the early morning sky as it moves around the sun in it's orbit. It is the highest on July 10th, about 15 degrees above the horizon at 5:00 AM.  Distance between each horizontal grid line is 20 degrees.

The evening views are a little better, and the comet gets higher each succeeding night, but also dims as well.

Comet NEOWISE - Evening
Reisterstown, Maryland

Recent reports put comet NEOWISE at magnitude 1 - 2, which is certainly bright enough to be visible with the naked eye, but I would bring along a pair of binoculars if you have them.

Depending on the weather, I may be transporting my portable telescope to try to capture some images.  Later in the month, when the comet is high enough to clear my treeline, I'll capture it with my larger rig.

Graphics courtesy of Starry Night®
(Starry Night Pro) (Version 8) / Simulation
Curriculum Corp.

The Dumbbell Nebula - M27

Getting around to completing the postprocessing of a number of astro objects in my backlog. Part of my backlog of image runs, this image con...