Gina's DIY All Sky Camera - Mark3 - with QHY5L-II-C

[Gina]

Dew heater control working and dew heater drawing the designed 0.7A when on

[Gina]

For a bit of light relief, here are a few screenshots with the camera looking out of the window.

[RLWP]

Toggenburgs?

Richard

[Gina]

Yes   Except for the white one who's a Saanan (or British Saanan to be precise)

[Gina]

Focus stepper motor connected to circuit board and 12v supplied - working correctly   So, with everything working I will now reassemble everything and do a real test

[Gina]

I plan to just run the dew heater on 5v for tonight rather than push getting the DHT22 and automatic dew control working and ending up not having anything ready by dark.  I expect to sort out the humidity and dew point measurement tomorrow.  I've had this working in the past so don't expect too much trouble   Famous last words

[Gina]

Assembly complete now to test it

[Gina]

Seems to be working

I had a thought about what might be wrong with EZPlanetary.  Originally I had it set to save to drice C: then I ran out of space and changed over to D: where there was plenty of space.  I think that could have been when it stopped working, so I've moved 20GB pf data from C: to D: and set EZPlanetary back to saving to drive C: and it's working again

CONCLUSION:-  EZPlanetary has a bug such that saving to a different drive screws it up

[Gina]

Here's a screencapture showing EZPlanetary working fine capturing an AVI file of 500 frames.  On the left the ASC control can be seen with the dome temperature.  This pretty much sealed unit is proving far more efficient than the previous incarnation for using the heating from the dew heater coil

The ASC is tilted towards the south as it is on its propper pole and this is currently hung by its bracket on the guttering with the bottom end of the pipe against the window.  I'm not mounting it on the obsy until I have it working fully.  ie. with automatic dome temperature control.

[Gina]

The clouds seem to be going away now

[Gina]

It's dark now and I've been experimenting with EZPlanetary capture.  I've found I can capture TIFF files at the same time as recording an AVI file.  I have not yet tried dark frame subtraction - I'll do that another night.  I am using an exposure time of nearly 90s.

Here are a screenshot of the remote screen and a SNAPshot TIFF file copied across to my local desktop and enhanced with curves in Photoshop.  The result was cropped slightly and saved in PNG format for upload here.  The Milky Way is visible and I think with dark frame subtraction the result should be pretty good   The shape of the stars is far better with this setup than it was with the old QHY5.

[Horwig]

That is starting to look really good, 

H

[Gina]

Thanks Huw   Yes, I feel quite pleased with it

Here's another "improved" TIFF capture, saved as PNG.

[Gina]

The AVI captured overnight was pretty good   Nice clear night   Here is a clip from just before dawn showing the Milky Way plus a Photoshopped version to bring out the Milky way without too many artefacts round the brighter stars.  Frame exposures were 87s and other settings as per the screenshot above.

[Gina]

From the local weather forecast it looks like star watching will be off for several days   Cloud watching however could be a 24hr pasttime   Also, rain in the forecast could be an opportunity to see it dew heating can be used to dry off raindrops   (I'm in "cup half full" mode ATM )

I've been thinking about the "dark frame subtraction" business and remember that temperature plays a part in standard astrophotography.  So I think a temperature sensor on the camera body would be a good idea then I could match up saved dark frames with the current temperature.  It only needs a DS18B20 attached.  Also, it would be interesting to see just how well the heat was being taken away by the akluminium pipe.

[Horwig]

One thing I've not done is find where ezPlanetary puts its stored dark frames.

H

[Gina]

No, nor have I but I'm about to

[Gina]

Well, I've tried but found nothing   Tried looking in all the places I could think of and also searching the whole computer for "Dark"/"dark" - only earlier standard darks found going back over a year.

Had a thought...  Maybe it got saved in the program folder and got deleted when I reinstalled.  I'll try again.

[Gina]

Well, I've saved another stack of 10 dark frames (somewhere) but I can't find them

I'll do it again and see if using them give me a choice of which batch.

Bit later... Saved another batch with different settings and then tried the "Enable Correction" but no choice given.  I guess the lasr save overwrote the previous one.

[Grotemobile]

Well, I've saved another stack of 10 dark frames (somewhere) but I can't find them

I'll do it again and see if using them give me a choice of which batch.

Bit later... Saved another batch with different settings and then tried the "Enable Correction" but no choice given.  I guess the lasr save overwrote the previous one.

Ez  Planetary, has a habit of storing things  on the, Local Disc C. 

That is were the actual program, has down loaded to,  on my computer.

Steve.

[emadmoussa]

Pretty impressive!! 

[Gina]

Thanks Steve   Yes, I came to that conclusion but I can't find where the dark frames are stored.  Not to worry - dark frame subtraction works   It's just that you can't make a library of darks and choose the appropriate one.

I have saved a stack of 10 60s darks and used dark frame subtraction on both 60s and 90s captures.  The 60s darks seem to work quite well for 90s frames as well as 60s ones

These are frames captured as TIFF files, cropped and saved as PNG for upload here - no other processing.

60s dark frame.

And this is a 90s frame using the 60s dark frame subtraction.  This is with shutter closed as it's too light to do anything else.

And this is a 90s exposure without dark frame subtraction.

[Gina]

To highlight the difference I have applied identical curves in Photoshop to both plain and corrected 90s captures.

Plain.

Dark frame correction applied.

This is using the 60s dark stack on a 90s image.  I'll now capture a 90s dark stack.  Back in >15m

[Gina]

Here is the "propper job" - stack of 10 90s darks applied to a 90s image with curves applied exactly as above.

Think I'll try pushing it a bit further

[Gina]

OK more pushing in curves.

Plain.

Corrected.