M94

[ampleamp]

Another dataset from 18m ago using @Petergoodhew 's rig when it was at ICA. This is 52x600s luminance and 20x300s for each of the RGB channels. The outer ring was barely above the noise level in single L subs, hence the volume. which definitely helped in processing. Taken with a 1200/152 TMB and QSI6120. 

Thanks for looking. 

[alan potts]

Stunning image and a strange galaxy this one, never seen it like this as far as i recall.

Alan

[ampleamp]

Thanks for your comments Alan. I managed to make a mask in PI that allowed me to draw out some of the outer ring, and of course the dark skies helped. However on a single sub it is barely visible. 

[vlaiv]

How was this image processed?

I suspect that drizzle integration was done for some reason as image size (height x width in pixels) is twice the size of sensor pixel count?

Drizzle integration is going to lower SNR and as is, 3.1um pixel at 1200mm FL is already oversampling by factor of x2 at least. This means that you could have at least x4 SNR if properly processing the data.

[ampleamp]

vlav, I drizzle integrated the Lum in PI as to my eye it gave a better Lum base (better stars and galaxy) on which to work. I obviously forgot to re-adjust the image back to normal size and a crop of the edges will account for any pixel discrepancy. I tend to go with eye rather than the theory but I do hear what you are saying. I think I still have the original integrations (normal and drizzled) so will compare the snr and see how that comes out. Thanks. 

[orionoffelt]

A nice image for a difficult target.

Bob

[ampleamp]

Thanks Bob.