Almost the summer triangle

[happy-kat]

Lucky enough to have a clear night and in a bortle 4/3 site, I was in Guernsey. I would have imaged East but that faced the airport and the lights were still on creating a bit of a light dome so I faced South but above a lone house light otherwise there were no lights, what a change for me.

Slightly higher in the sky then I wanted to point but above the lone light, cottage gable and tree line. I forgot to pack my red dot finder so camera aiming was more of a challenge and I used a gorilla tripod and controlled the camera using DSLR Controller. I took a gamble as I could not move the histogram off the left edge unless I left the lens wide open and 1600 ISO is the max I can use before lots of noise shows. Canon 1100d with pancake 24mm at f2.8 and 10 second exposure as anything more and the trails were just too noticeable. Unfortunately this lens is not as good as the 40mm pancake lens as it has very poor corner control  so next time I will either use the 40mm or take the Ashai 50mm f2 as it is much better.

I took 122 light frames and various calibration files. Stacking I tried a mix with varying degrees of cropping before processing in StarTools and a final HLVG medium strength in PaintShopPro, all images were binned 50% before processing further.

This image was from the entire stack and was heavily cropped and I feel has the best colour.

I then processed the stack into three batches of 40 files with a light crop and once processed stitched using ICE.

Platesolved using astrometry.net

To see the full extent of the unpleasant corners then here it is the single stack of 122 lights, though at least you can now see Vega, Altair and Sadr (couldn't quite include Deneb)

 

[happy-kat]

Naked eye observing was lovely the Milky Way was so clear to see.

[happy-kat]

My plan is next time remember to use my other lens and the red dot finder, then take at least 60 lights of each triangle star and process the stacks, then use ICE to stitch.

[happy-kat]

On inspecting a single frame the star shapes are quite OK, I am then suspecting it was more to do with field rotation at the corners because of the direction and elevation producing the blurred stacked corners. the 24mm panacke lens is only in EFS fit (unlike the 40mm which is only EF fit) and I have this lens profile loaded onto the 1100d so the single frame looks surprisingly flat with fairly OK corner stars.

Here is a single 10 second light frame taken on a static tripod, using irfanview raw saved as tif, opened in Startools light stretch, colour adjust and saved as tif then irfanview to save tif to jpeg for upload here.

FWHM was 3.26 and a score of 10392.98

 

[nfotis]

Nice result. Were you using JPEG images, or CR2 files?

 

N.F.

 

[happy-kat]

Thank you. I suspect raw files but I'll check when next at the pc.