M81 - First light(s?) with Atik 314L+

[Parallax]

What a great camera, so much better than my 16ic-s. Yes it was twice the price but more than twice as good. It's so much easier to process the images, having 3 times as many pixels. And very low noise too.

Thanks go to those who recommended it.

M81, LRGB.

20x300s L, 10x180s binned x2 for each R,G & B. No calibration.

C80ED, Atik 314L+

Guided with ST80, Atik 16ic-s

Captured/guided in Maxim

Processed in PS CS.

Steve

[NickK]

Good stuff

Only a couple of personal observations rooted in my preference for detail.

1. That camera can do 1x1 binning very quickly due to it's sensitivity. I think if your seeing is good this would add additional core detail. There's a lot of 2x2 binned detail in that core already! Any chance of just a 1x1 lum stack image?

In short you're getting a 2x2 RGB image but backlit by the 1x1 lum. So the RGB gets subtle intensity differences but the observable detail is still more like 2x2.

2. The stars are saturated, this appears as a flat colour diamond shape stars (right side 2/3rds of the way down). Non saturated would be a pinpoint (or a circle with only a small saturated pixel in the centre and a graduation away from it). This would lead to a large dynamic range in the brightness of the stars and the subject (m81) resulting in a more 3D feel to the picture.

Just my ramblings - but a mighty fine first light!

[Whippy]

That's a cracking result for a first light Steve, subtle and smooth processing. Congrats .

Tony..

[steppenwolf]

An excellent first light and I like the subtle processing that you have applied to the image.

[Parallax]

Here is the 1x1 L image.

Nick

1. The reason I binned the colour was more of a test really. I usually don't bin these days (or nights even).

2. I noticed when the L subs came in that the stars were saturated (65535). I didn't encounter this with the 16ic-s. Maybe it is faulty. Do I then just lower the exposure time or take different exposure lengths and HDR them?

Cheers

Steve

[NickK]

Here is the 1x1 L image. Nick

1. The reason I binned the colour was more of a test really. I usually don't bin these days (or nights even).

That's got some really nice detail into the core. Although it's not as far different than I was expecting! Shows how good the original image was! For example - look at the stars about 4-5 o'clock position in the core where the spirals go under them. Also the dust lane at 6-7 o'clock from the core, there's a y shape on the 1x1 that's missing with the RGB 2x2 Ooo the detail

2. I noticed when the L subs came in that the stars were saturated (65535). I didn't encounter this with the 16ic-s. Maybe it is faulty. Do I then just lower the exposure time or take different exposure lengths and HDR them?

It may be because the larger 16ic pixel size (7.4x7.4um) vs the 314L+ (6.45x6.45um) means the 16ic is very likely to have a larger electron capacity per pixel. Sony only give "relative" QE values too so it could be that there's a sensitivity difference between the two chips too. The 7e vs 4e read noise level also makes me think that 314 has a smaller electron bin capacity.

Only way to reduce excess electrons is to reduce the number of photons hitting that area per exposure (less exp time, slower scope etc).

[rocketandroll]

Very nice Steve!!

I see the EQ6 is working for you then... can I have first bagsie on that one too once you upgrade again! :-)

Awesome pic tho... lovely to see so much detail in M81.

Ben

[ollypenrice]

I'm seeing two luminance images now and no LRGB anywhere...

It's a great result on the L, anyway. Background sky not at all clipped, core nicely controlled, detail showing in the spirals.

No flats? Boy, you keep a clean setup, Sir!

Olly