GOTO required for ZWO ASI120MM ?

[GibbyNI]

Just a quick question, im not upgrading my telescope till next year and currently have the skywatcher 130mm with no goto mount.

I'm just wanting to start messing around with planet photography before I get the new scope, is this possible with out goto?

 

Thanks

 

Chris

[spillage]

Hi Chris,

It is possible but difficult. You will have to manually track the planet as best you can to keep it in FOV. But you find that you will have to dump allot of frames. My way of thinking is give it go. If it work great if not at least you have tried.

 

Cheers

Spill.

[MARS1960]

In my humble non planetary imaging lay opinion , i would think you will be fine, apart from a low Jupiter there isn't much to image planet wise and i'm sure Jupiter responds best to a short capture due to the fast rotation, so a 60-90sec mov at 30fps should be about as far as you would want to go, i think .

[Zakalwe]

GOTO is not necessary. Tracking is though.  The challenge is that to capture any sort of detail on something like Jupiter you will need a long focal length. Think in metres of focal length. At that length you'll find that the planet will drift off the chip very quickly, especially with a small sensor.

Manual tracking might work but you might be better experimenting with Lunar imaging first.

[michael.h.f.wilkinson]

All you need is a tracking mount (although some die-hards got great results with a Dobson). My venerable (21 year old) Vixen GP mount gives excellent results on sun, moon and planets.

[TareqPhoto]

I tried to imaging the mood without the tracking tool, it was very very difficult, the moon is moving fast along the frame of ASI120MC, so i gave it up until i can use my mount.

[ollypenrice]

Go To and tracking are entirely different things. You can have tracking without GoTo but you cannot (in the real world) have Go To without tracking. It is tracking which you need for bearably easy imaging.

Olly

[Stub Mandrel]

I started by taking short videos and when the planet got to one side of the screen I would stop the video twiddle, the knob until it went back off the other side, then restart the video when it reappeared.

It all became quite easy, in fact I worked out how long a video I could shoot in each run, so all I had to do was click 'record'.

Done on a 150PL and EQ3 with no tracking or goto and a cheap webcam.

 

[GibbyNI]

1 hour ago, Stub Mandrel said:

I started by taking short videos and when the planet got to one side of the screen I would stop the video twiddle, the knob until it went back off the other side, then restart the video when it reappeared.

It all became quite easy, in fact I worked out how long a video I could shoot in each run, so all I had to do was click 'record'.

Done on a 150PL and EQ3 with no tracking or goto and a cheap webcam.

This is exactly what i was thinking but wasn't to sure if the software could cope with the image moving so much. I have done some basic stuff in deep sky stacker with my 700d and a zoom lens so things don't move that much between exposures.  What software where you using to create the image?

[ronin]

If the mount is equitorial and there are the flexible RA adjusters then you should get something. I would say the trick is to display the image on the PC while capturing the avi.

You will have to use a high frame rate and practise beforehand at maintaning the image of the planet central. At 30 fps I would suspect you will want around 20 seconds worth of video. Around 600 frames. You would take the video and determine the best single frame then tell the software to select the 100 that best match that frame. Then get it to stack those 100, you could try for 150 frames and compare results.

Initially stack in Registax and process in that also, little point in swapping software half way through, and that keeps it simple. The software performs some realignment of the frames captured. Think you might find that AS2 does this a bit better but until you get results I still think that using just one package is a better option.

Have seen a few "guidelines" on the processing - done by moving the wavelet sliders, usually there are 7 of them located on the left hand side of the Registax window. You can play, which is likely hte simple one. Have seen one person just move all 7 to the centre, another ended up with a slight gradient as they moved down to the next wavelet - kind of 20% to 80% going down each, one I read the person said what they did was just move wavelet 3 all the way over to 100% and leave the rest unaltered. So basically no rule or real guidance others then play and have fun, but all to the middle is easy, and makes a changed.

 

[Stub Mandrel]

11 hours ago, GibbyNI said:

This is exactly what i was thinking but wasn't to sure if the software could cope with the image moving so much. I have done some basic stuff in deep sky stacker with my 700d and a zoom lens so things don't move that much between exposures.  What software where you using to create the image?

The secret is to use PIPP 'Planetary Imaging Pre-Processor' (it works for the sun and moon too). It takes your video and uses all the frames with a complete planet to create a new video with a smaller frame and the planet centred ready for stacking. It can do some other useful stuff which can help with making the best of things like under/exposed video.

My workflow has changed a bit, but now it's: Prepare in PIPP, stack in AS!2, wavelets + RGB align  + (sometimes) gamma adjustment in Registax, derotate in Winjupos (if stacking a lot of good data), sharpen & noise reduction in Astra if required.

You can get great results with just PIP --> AS!2 --> Registax

[Chris]

What mount do you have with the 130p, is it an EQ2? if so just buy an RA motor drive for it so you can track objects.

[Stub Mandrel]

Here's an approach to Registax wavelets on the web I found that works very well.

RGB align if needed

Choose dyadic wavelets.

Set number 2 to 100%

Increase denoise until it stops looking horrible

repeat for number 3, number 1 and optionally number 4 in that order

It is important to get rid of ALL artefacts generated at each step.

Any further wavelet changes should be small.

If you cant get a sharp image without having a 'ring' around the edge of the planet, use the denoise/deringing function.

 

[Astrosurf]

I've found 2 mins is perfect for me, at about 25fps. Any more and I would need Winjupos, but I don't understand it. But 2 mins of trying to keep the planet in the FOV might be a bit tiring! Good luck!

Alexxx

[michael.h.f.wilkinson]

Centering the planet on a small chip can be a right pane without tracking, I find (and even with tracking, it can be a hassle. I also tend to set fire-capture to 2 minutes as a limit, then either run through PIPP or directly stack with AS!3 (available for a while now), and do wavelets in Registax. I tend to go for linear wavelets, and already start tweaking the lowest (no 1) band. Most, if not all the denoising I do in that band, and a little in band two. I do not push the higher bands up too much