SDC 435 first light & settings

[DoctorD]

I finally got my C mount to 1.25" adapter for my SDC 435 and was eager to try it out.

Bearing in mind that I have a modest sized scope with a slow F ratio (Skywatcher Skymax 102 on Synscan AZ mount at F12.7) I was not sure what to expect.

Having originally seen the SDC on Steve Wainwright's QCUIAG web site, I started with his recommended settings:-

Lens: DC

Shutter: ESC

AGC: High

SENS-UP: Auto (limit 512)

SSDR: ON

SSNR3: ON

First light was an the 24th April - and I found it impossible to see anything - the picture always seemed to end up white. I have pretty bad light pollution at my home with an LP sodium street light at the end of the street. I reduced the sens-up limit to 128 with no real improvement.

I finally gave up and spent the last 30 minutes looking at Saturn and then captured a short clip with my un-modified Toucam Pro.

I had another go with the SDC 435 on the 27th April and decided to play with the settings.

Lens: Manual - after all, the camera has no control of the scope!

Shutter: manual - see below

AGC: High

SENS-UP: - (option disabled by manual shutter)

SSDR: ON/OFF (I did not see much difference but will try again another night)

SSNR3: ON

I also used my 0.6 focal reducer and Neodymium filter (IR filter now removed from the camera).

I used the two star alignment for the Synscan with Arcturus as the second star.

Once aligned I replaced the eyepiece with the camera and reduced the shutter setting until I could see the star (1/50s) - at last I was making progress.

I tweaked the focus to make Arcturus as small as possible then slewed the scope to M3.

Just within the field of view was a faint smudge - I adjusted the position until the smudge was in the centre of the picture then slowly increased the shutter to 64 (anything greater than 1/50 uses frame accumulation I think).

After a few seconds a ball of stars began to appear!

My first video DSO - I increased the shutter to 128 and grabbed a couple of minutes of video.

It takes sometime for the picture to stabilise after changing the shutter setting and I found settings greater than 128 caused the sky to begin to white out. This is probably due to the fact that M3 was directly above the street light.

I dialled in M5 and found it almost immediatley - captured another few minutes of video and then called it a night.

All I have to do now is get to grips with Dark Frames and stacking

I'll post the photos once I've processed them.

Is anyone else using manual exposure or have you been able to work with the ESC shutter and auto sens-up as recommended by Steve Wainwright?

One advantage of the manual setting is that I was able to capture some dark frames at 64 and 128 frame accumulation and could guarantee that would match my earlier exposures.

It seems to me that full manual control is better than the auto mode.

Can't wait for the next opportunity to use the SDC435.

Clear skies

Paul

[Catanonia]

Never used the camera before, but pure white would seem to indicated over exposed.

[StevieDvd]

Go on post the images.

What are you using to view/capture?

[DoctorD]

Hi

I'm using SharpCap with an EasyCap DC60capture dongle to view and capture the images on my laptop. Capture was using no compression so I ended up with about 2G files for my 2 mins!

I only captured a couple of minutes of video at x128 so that's about 45 frames of real data. I used ImageGrab to extract every 64th frame as .BMP

To be honest, I am happy to see anything after my first night with the SDC 435 so did not look at the exposure and settings to much.

Here's a single dark frame a single light and the output of DSS as processed and one with the levels adjusted to remove the background noise (both were .FTS and converted to JPEG in IRIS).

You can see from the output of DSS that I seem to be having problems with the dark frame.

I must read the DSS manual!!!

Clear skies

Paul

[DoctorD]

Hi

I've been trying to improve the post processing and in particular sort out the dark frame.

Below is my best attempt so far.

Stacked in DSS, saved as a 16bit TIFF and post processed in AVISTACK 2 - basic level adjustments only.

I'm now happy with my first DSO image.

Clear skies

Paul

[DoctorD]

Hi

I've been trying to improve the post processing and in particular sort out the dark frame.

Below is my best attempt so far.

Stacked in DSS, saved as a 16bit TIFF and post processed in AVISTACK 2 - basic level adjustments only.

I'm now happy with my first DSO image.

Clear skies

Paul