M76 - First image with ZWO ASI 385 + 300/160 Newtonian

xs_man

Hi Sam,

Hi All,

Here is my first image with testing camera ASI 385.

M76 is an interesting target in short exposures because it's not a very bright

planetary nebula and it shows some faint extensions. Moreover a difficult

double-star is visible at the center of nebula.

Here I mixed 5 seconds, 2 seconds, 1.5 seconds, 1 second exposure. Imaging

session includes2 nights (25 and 26 October) but I have fog which cuts a part

of the light. So bad transparency.

I choose 8 bits during capture, not the best idea for sure. I will use 16 bits

mode next time.

The anti-amp glow works fine !

Only a little problem : on the Raw image, a strange phenomenom appears : stars are

saturated but the level is not at 254 as expected for 8 bits mode. It seems that

the dynamic is reduced or cut by a threshold ? Very strange. If gain is lowered, the

levels of saturated stars are also lowered. Please Sam, could you take care of this

problem ? :?:

SETUP :

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Newtonian Orion Optics 300 mm F/D 5.3, on EQ-6 Mount

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ZWO ASI 385 without filter,

2595 x 5 seconds exposures.

1319 x 2 seconds exposures

2053 x 1.5 seconds exposures

4370 x 1 second exposures

Gain = betwen 37and 400.

Darks.

Visual sort out of Raw images.

Registration with DSS.

Processing and post-processing with Iris + Photoshop.

Final image, resized at 110% :

5 sec Raw image at 100% :

~~Albéric~~

gymbow

That is a beautiful image. But the # of short captures taken is insanely large, requiring huge storage space and processing power. What results can you achieve if you take equivalent total duration, but with 5-10 minute sub-frames?