NGC1499 and Crab nebula

[kimo]

NGC1499 and Crab nebula.

[bornfree]

i like the crab..

[kimo]

Thanks.

[PETER LOO]

Hi Kimo, your M1 Crab Nebula shot is outstanding, good signal to noise ratio, field is significantly flat, no sign of coma & most importantly, can distinctively see the filament structures (good resolution), it makes my heart move & wanting to come back to AP so soon (much less than 2 years that i thought i wanted to go absent). I presume you used around 1,00 mm focal length to shoot this radio source object ?

[kimo]

Thanks Peter Loo, yes, you should start AP again. it was taken with FL 420mm, 2hr 27min, 15min and 8min Exposure. i just got SII filter n will add SII next time.

[PETER LOO]

Thanks Kimo, amazing ..

[Gary]

Good shots. Thanks for sharing.

[yltansg]

Hi Kimo,

Nice, what is your setup like?

Alfred

NGC1499 and Crab nebula.

[kimo]

Thanks.
Main scope: Achrometic Refractor .
Camera: Dsi pro II
filters : Ha-OIII

[PETER LOO]

Hi Kimo, your "method of Optical Crop" is interesting & it shows that it worked ! i guess you'd used a very fast system of f 3.5 (F5.0, 600 X 0.7 probably). Canon 500D has a sensor size of 22.3 X 14.9 mm whereas DSI Pro II sensor size has crop factor 4 X, this make a 420 mm scope to have a 420 X 4 = 1,680mm scope FOV, (while the actual focal length remains the same, hence, it explained why you need more light - i think). What make it worked in resolving the filament probably is the "Resolution Gained". The remarkable thing is you still have to guide it precisely since the picture will look as if it was taken with a focal length of 1,680 mm scope, it is like using a high power eyepiece for visual work, drawing a parallel ..