Etcetera
Assorted throwaway pancakes
More often than not astrophotos don’t come out the way you planned them to. There are about 200 steps involved in taking a picture, and they all have to be right. Also, often we need to experiment, finetune equipment or the sky is not good enough for long enough to finish a project. These are some examples of failures and experiments.
Arcturus (26 Mar 2022)
Just a quick test image, but it is calibrated with flats and it might be interesting to see the same starfield through a Bahtinov mask. The black dots are due to the Bad Pixel Map (it’s a map that shows where the faulty pixels are on the camera sensor).


| Details | |
|---|---|
| Telescope | Skywatcher Esprit 100ED (f/5.5) |
| Filter | Astrodon LRGB Gen2 E-Series |
| Coma corrector | - |
| Field flattener | Skywatcher Esprit (1x) |
| Camera | QHYCCD 268m, -20°C, Mode 0, Gain 26, Offset 30 |
| Resolution | 3112x2071 (cropped & scaled 50%) |
| Light frames | R: 1 (60s) |
| G: 1 (60s) | |
| B: 1 (60s) | |
| 3m total | |
| Flat frames | 16 each |
| Darkflat frames | 16 |
| Dark frames | - |
| Bias frames | - |
| Location | Bolton, UK |
| Local time | 2022-03-26 01:21 - 01:33 |
| Field of View | |
| Image Center |
Rosette Nebula (20 Mar 2022)
First attempt of the Rosette Nebula (NGC 2237). Apparently astrophotograpy and fog can never be friends. Also, the Ha flats are overcorrecting so a quick articial flat was also used for that layer. (see the dust mote on the right).

Same data denoised and dustmote removed (by using the flats properly):

| Details | |
|---|---|
| Telescope | Skywatcher Esprit 100ED (f/5.5) |
| Filter | Atik Narroband 7nm Ha/SII/OIII |
| Coma corrector | - |
| Field flattener | Skywatcher Esprit (1x) |
| Camera | QHYCCD 268m, -20°C, Mode 1, Gain 56, Offset 30 |
| Resolution | 3071x2027 (cropped & scaled 50%) |
| Light frames | H: 4/12 (300s) |
| S: 8/8 (300s) | |
| O: 8/8 (300s) | |
| 1h40m total | |
| Flat frames | 8 each (3/60/10s) |
| Darkflat frames | 16 each |
| Dark frames | 10 |
| Bias frames | - |
| Location | Bolton, UK |
| Local time | 2022-03-20 20:15 - 22:17 (light frames used) |
| Field of View | |
| Image Center |
Deneb (15 Oct 2021)

| Details | |
|---|---|
| Telescope | Skywatcher Esprit 100ED (f/5.5) |
| Filter | IDAS D2 (multi-bandpass light pollution filter) |
| Coma corrector | - |
| Field flattener | Skywatcher Esprit (1x) |
| Camera | Canon 7D Mark II |
| Resolution | 5482x3679 |
| Light frames | 2 (180s @ ISO 1600), 6min total |
| Flat frames | - (artificial flat) |
| Darkflat frames | - |
| Dark frames | - |
| Bias frames | - (reused from Soul Nebula 2022-01-05) |
| Location | Bolton, UK |
| Local time | 2021-10-05 21:20 - 21:31 |
| Field of View | |
| Image Center |
Sadr (15 Oct 2021)

We also have a processed image about the Sadr region.
| Details | |
|---|---|
| Telescope | Skywatcher Esprit 100ED (f/5.5) |
| Filter | IDAS D2 (multi-bandpass light pollution filter) |
| Coma corrector | - |
| Field flattener | Skywatcher Esprit (1x) |
| Camera | Canon 7D Mark II |
| Resolution | 2698x1801 (scaled and cropped) |
| Light frames | 10 (180s @ ISO 1600), 30m total |
| Flat frames | - (artificial flat) |
| Darkflat frames | - |
| Dark frames | - |
| Bias frames | - (reused from Soul Nebula 2022-01-05) |
| Location | Bolton, UK |
| Local time | 2021-10-05 21:38 - 22:10 |
| Field of View | |
| Image Center |
Mizar & Alcor (13 Apr 2020)

| Details | |
|---|---|
| Telescope | Skywatcher 200/1000 Newton |
| Filter | |
| Coma corrector | Vixen R200SS |
| Field flattener | - |
| Camera | Canon 400D |
| Resolution | 1852x1235 (cropped and scaled) |
| Light frames | 10 (180s @ ISO 400) |
| 10 (360s @ ISO 400) | |
| 1 (1200s @ ISO 400) | |
| 1:50h total | |
| Flat frames | - (artificial flat) |
| Darkflat frames | - |
| Dark frames | 6 (180s) |
| Bias frames | - (reused) |
| Location | Bolton, UK |
| Local time | 2020-04-13 21:52:20 - 23:43:12 |
| Field of View | |
| Image Center |