Astrophotography – deep sky

M45

ts been a while now since i posted my preliminarily preview of the Esprit 120 mostly due to a combination of work/family/bad weather and Xmas parties. On Friday evening the forecast was clear until around 7ish so i was able to get a few shots of M45. I chose M45 as its a great star cluster which would be good to determine star shapes in the corner of my sensor.

I was able to get 26×2.5min before the clouds started to roll in. For this test the position of M45 wasn’t great so there is a light pollution gradient etc, which isn’t important to determining star shapes, optical errors.

Anyway looking at my RAW images id say the scope covers about 98% of the sensor. For the remaining 2% a very small amount of vignetting is visible with a strong histogram stretch and an ever so slight amount of coma on stars at the extremities of the image. If your using a 36mm sensor like me then a very slight crop is necessary, although most people would do this anyway. If your using a standard APS-C Dslr then your stars are pinpoints to the edge! Very impressive in my book. Zooming into a bright star i can see no signs of star bloating.

I don’t know how Skywatcher are able to achieve such high quality for such a low price (in comparison to high end competitors) but im delighted!

The image ive posted is about 75% crop, for your perusal if anyone wants a full uncropped image please let me know.

Crescent Nebula (SH2-105)

First attempt at imaging since the new floor was completed in the Observatory.

Focused by hand as the electric focuser is currently not working – hence not quite in focus.

This is a 7×5 minute stacked image taken through a Hydrogen Alpha filter. Telescope being a Takahashi Epsilon 180ED at f/2.8. (A brute to manually focus!) Camera; Atik 4021, cooled to -27 degrees. Guiding by PHD and all sitting on a modded EQ6.

 

Also an image of IC1318, the diffuse Hydrogen Alpha emission nebula surrounding ‘Sadr’ (upper right), the 2.2 mag star at the ‘heart’ of Cygnus the Swan.

 

Geoff

 

Another go at Sadr

Finally got a finished version of last Saturdays subs- I’d left the camera running on Sadr before setting off to meet Neil. I managed to collect 16 ten minute Ha subs (it was a bright moon), along with another 10 of the shed wall whilst the rig was running unsupervised (not included here!). I used them for the B&W image below, then combined them into the red channel of an RGB image from 9th October on the same target (see here for previous effort: https://roslistonastronomy.uk/imaging-sadr-and-observing-the-veil ). My framing was a bit different this time (framing is a bit random at the minute for me- I’ve definitely not got on top of this yet…), so the colour image below is the intersection between the 2.

M33 club – – – !

After having been seriously impressed with Rob and Ken’s latest splendid M33 images, I thought it might be interesting to compare them with one from the other end of the spectrum. Rolls-Royce vs. Ford Popular, sort of!

This one was a couple of years ago with the window-sill telescope that was on holiday at the time, sat on a patio table.

It was probably from a total exposure of about 200 seconds, if I remember correctly. The 80mm f/5 isn’t really compatible with the focal reducer, mind you.

What does it prove? Nothing, except that there is fun to be had, even if you only spend a couple of hundred pounds!