Author Archives: Kenneth Crichton


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.

Flats light panel

Since I’m currently looking to change to a mono camera I thought it would be sensible to have a look at making the flats process easier.

I’ve seen a few posts over the years where people have produced a light panel and added A4 paper to the front giving a nice flat illuminated area.

I wanted to do something similar so I purchased a cheap LED panel on amazon and cut around the telescope circumference. I left the box around the panel and added Velcro to the inside to keep it flat against the outside. I also cut out the power inlet and on/off button.

Very pleased with the result ! I’ll keep it velcroed to the inside of the observatory.

M33 Pinwheel

Sunday night was clear so i decided to have a second go at M33. This is the second time Ive attempted this galaxy as the first from last year was slightly out of focus. It was a poor night seeing wise and my “clear outside app” was actually orange/red for most of it but Im pleased with the improvement from last year. I still feel i need to add more subs or would better seeing make that difference??? I actually tried to view the galaxy with a set of 70mm binos but it wasn’t visible. 100×2.5min plus darks, flats and bias. Processed in pixinsight.