alan4908

If you want to image at 0.93 arc seconds/pix then as as rough guide you need your rms guide corrections to be consistently less than half of this value eg better than about 0.46 arc seconds. If they are more then they will impact the shape and size and stars.  The information above suggests that even with a belt modification you are going to struggle to achieve satisfactory results. 

Alan  

From my experience of the NEQ6, I found it was quite happy to guide at around 1.4 arc seconds/pix producing subs with 30min duration without issue. However, after spending many hours adjusting various guiding parameters, I got the impression that I was on the limit of the mounts performance capabilities. 

At 0.93 arc seconds/pix I think you will struggle to obtain consistent results due to the intrinsic tracking limitations of the mount, even if you are well inside the imaging weight limits of the mount.

Alan

1 hour ago, serbiadarksky said:

How much are the galaxy images cropped? I am sure thats not the real fov as the esprit 150 doesnt have that much fl.

I don't honestly know, all I do is crop my images until I get the prettiest picture !    

In imaging, the field of view is determined by the focal length of your scope and the pixel size of your camera. To see the various FOV with a specific scope and camera and object have a look at https://astronomy.tools/calculators/field_of_view/  

The Trius SX814 gives my set up an imaging scale of about 0.7 arc seconds/pixel, which is quite a high resolution. 

Alan

20 hours ago, Seanelly said:

Further info, if possible, available upon request. Ideas, suggestions, or a solution would be greatly appreciated, as I have no idea what in Heaven's name (or Earth's) is happening here.

I've had to look at your image and in addition to the horizontal lines you have a collection of dust donuts.  To minimize these, I suggest take some flats, the most consistent and reliable method that I've found to do this is via an EL panel.  If you find flats/darks/bias a bit of mystery then I'd getting a copy of Steve Richards excellent book  "Making Every Photon Count"  - https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

You can also minimize both of these unwanted effects in PS.  The horizontal lines can be minimized by one of Noel Carboni tools called Horizontal Band noise reduction, the dust donuts via the context sensitive spot healing brush in PS. You can download Noel tools from https://www.prodigitalsoftware.com/Astronomy_Tools_For_Full_Version.html  and represent excellent value at $21.95.

Alan

1 hour ago, Saganite said:

Great images Alan , but for me The Ghost is just fantastic !

Thanks ! 

Alan

It was quite difficult for me to select five of my favorites from a productive 2018, but here they are. All are taken with my Esprit 150.

Alan

SH2-136 (Ghost Nebula)

M106

NGC1333

NGC4631

NGC4685

An excellent write up Steve. 

The only major difference from my own workflow relates to the star selection process for the PSF creation. So for me:

1.  I constrain these to be within my camera's linear region, in addition to having a minimum signal level,  so for me, the max value is about 0.6. 
2.  I never (try) to pick stars that are embedded within nebulosity since their stellar profile will most likely be contaminated by the nebulosity.  
3.  To minimize optical distortions I try to pick stars that are near the center of the frame.

After you have created a list of candidates, Adam Block's Pixinsight deconvolution tutorial advises that you should sort the Mean Absolute Deviation (MAD) column and look at the numbers.  This gives you an idea of the quality of the input data.  Apparently, what you are after is a consistent set of numbers within a factor of say x2.  If you find something outside this range then you should consider deletion of the outliers.

Alan

2017 was productive for me, I found that my transition to unguided imaging has significantly improved my imaging productivity.  Lost guide stars used to be a significant problem area - but no more.  

Anyway, here are five images from 2017, all taken with my SW Esprit 150 and a SX Trius 814.

Alan

M1

M82

M81

NGC7635

NGC6888

3 minutes ago, Pickwick said:

Hi Alan,

Thank you for a comprehensive reply, I have been using the free trial version but have got stuck on ACP weather interface for HitechAstro relying on a script to interface with ACP. How do I set out to do this any example would help.

Cheers

 

Pickwck

 

 

Hi Pickwick

Firstly, you need to ensure that you have configured the Weather server via the HitechAstro app. 

To communicate between ACP and the weather server, you need to set up the weather ID in the ACP preferences tab weather (ACP->preferences->weather). The weather ID for the HitechAstro server is HitecWeather.Weather

To connect the sensor to ACP and assuming you are not using Scheduler (which will initate the connect automatically) you then go Weather->connect.

Alan

Some amazing images here and congratulations to all the winners !

Alan 

Very impressive, I must investigate the HDR program that you used to construct the images, it has worked very well.

Alan

43 minutes ago, Pickwick said:

Hi Alan

Unlike you I have a Pulsar Dome with Rigel Controled rotator and shuter control. MaximDl has an interface with the Boltwood Cloud Detector. I am really mainly interested in the shuter closure should rain be detected on the Hightec Delux do you use Maxim or the Hightec software to achieve this?

Many thanks

 

Pickwick

Hi Pickwick

I use the Hiitec software in conjunction with ACP to close and open the roof. The Hitec software monitors:

1. Sky conditions - eg how cloudy.

2. Rain - eg water content of the atmosphere.

3. Sensor inputs  - optionally you can you install sensors that inform the Hitec software if the telescope is in a "safe" position for opening or closing the roof.  This to prevent the roof opening or closing if the telescope is not in a "safe" position.

So, if my observatory is imaging and it detects that either the Sky conditions have become too cloudy or rain is detected then ACP will attempt to firstly park the telescope to a pre-determined park position. When the telescope is parked, ACP will attempt to close the roof, however, this will only be allowed if the telescope sensor inputs (which monitor the RA and DEC positions) allow it. Conversely, if the weather becomes satisfactory again (eg sky clear and no rain), then the ACP will instruct the observatory to open the roof, the telescope will slew to the predetermined target and carry on the imaging session. To prevent hysteresis, the rate of opening and closing is limited by ACP to a pre-configured rate.

The Hitec software is ASCOM compliment and ACP compatible which allows the observatory to open and close the roof according to the weather conditions.

In my setup, ACP have overall command of all the elements of my observatory and instructs the the other software elements eg Hitech software, Maxim DL, FocusMax etc what to do and when.

If it may be worthwhile you contacting Steve Richards aka @steppenwolf who has also automated his observatory. I understand that he has a Pulsar Dome and MaximDL but doesn't use ACP or the Hitec software.

Alan

3 minutes ago, Pickwick said:

The Hightec cuirrently does not appear to be available again how reliable?

I've found the Hitec astro sensor very reliable and use it with my ROR obsey in an automated set up. I would recommend it.

Alan

Since I'm ultra cautious about mixing rain with electronics I use a total of three rain sensors in my obsey.

The main one is  from Hitech astro which I've set to close the roof if it detects rain or if it detects clouds, this is configurable for local conditions,  it can also be configured to send email alerts.  This has never failed but it is reliant on the obsey PC functioning.  To guard against failure, I installed two backup sensors inside the obsey which are not reliant on my PC  (so in theory these should never trigger).   I initially installed a rain alarm weather monitor station which connects via a low frequency RF link to my house.  The main advantage is that it is battery powered and is very simple to install. The main problem is that it needs quite a bit of rain for the alarm to trigger. I therefore decided to install a second device (a Kemo rain sensor) which is more sensitive, it also incorporates a heater which is required to prevent false triggering from dew. Since it incorporates a heater, I decided to power this from my main 12v power supply. To guard against mains power supply failures, I also installed a detector inside the house. 

For your particular application, you might find that the Kemo sensor is suitable, it's also relatively low cost http://www.maplin.co.uk/p/kemo-rain-sensor-dc-12v-n21dd?cmpid=ppc&gclid=CMHhlI3rg9ICFeq87QodbvsCdA  and on rain detection it closes a self contained relay which you can use to trigger an appropriate alarm. 

Alan

Five images from 2016 - all taken with my Trius 814 and SW Evostar 80ED DS Pro:

M51

M33

M31 - (my first mosaic)

M106

NGC6888

Alan