SharpCap Forums

Hey guys,

Is it possible to live stack using this camera? I've been reading all the comments about live stacking and it sounds really cool, have tried but it keeps dropping frames. Also a question about the sequence, this is what I have been trying to do in order for each session. Please tell me if I'm wrong:

1) Take light flats
2) Take dark flats
3) Using the smartbrain histogram find the the best unity gain and exposure and apply the settings.
4) Autoalign
5) Polar align
6) Find something worthwhile to stack and live stack it, thinking maybe a bright nebula if I'm lucky to find one.

Hi,

yes, you should be able to stack with this - perhaps a globular cluster would work well, being fairly small and bright, for a first target.

First time out, keep it simple - forget about the darks and flat frames, even maybe forget about the smart histogram (set 8s exposures and crank up the gain until you can see the target in each frame). Set RAW16 rather than RAW8 and turn on live stacking.

If you get dropped frames, look in the SharpCap log to see if it tells you why - it tends to log when the number of dropped frames passes certain levels (4,8, 16, etc if I remember correctly), and a 'type' of dropped frame will be logged - dropped by camera (check USB connection, turn down USB speed), previous frame not processed (maybe your PC is struggling to keep up), etc.

You can also lose frames at the live stacking level - if they are not bright enough for star detection to work then they cannot be aligned and stacked - this will show up as the 'Frames Ignored' count in live stacking going up. If this is happening start by checking focus and increasing exposure and/or gain.

cheers,

Robin

Hi Robin,

Thank you I'll give this a try and let you know how it went. Have to wait for clear skies.

Yes, you can pretty much live stack using the 224MC. Not only globular clusters, but nebulae as well. Here you can see an example when I first started using the 224 and a SkyWatcher Evoguide 50DX (50mm aperture).

Hey guys,

So I did the following attached. I couldn't keep the M3 straight kept moving on me. After you live stack, what tool do you use to clean it up the pic?
PIPP? Deepstacker.Also how many minutes do I live stack for? I did about 5 min, maybe not enough?

Hi,

good to see that you are making some progress

I'm a bit worried that you are seeing things moving around a lot. What mount are you using and is it set to tracking while you are imaging? The stacking code in SharpCap can deal with small shifts of the image, but if your tracking is not happening (or really bad) then you will struggle.

Post processing the images can be done in any photo software (Paint.NET is basic, but free; Affinity Photo is pretty good and only about £30 or so, Photoshop is excellent but costs ££££££). The exact steps do depend on the software you use. However, I think that your best bet at the moment would be to keep trying at getting sharper focus and good tracking - that will give you the biggest returns in improved image quality at this stage.

cheers,

Robin

Hi,

I'm using an ALT-AZ GOTO mount and yes the tracking is set to sidereal. I was floored when I saw that image of the globular cluster
Another clear night ahead will definitely press on all look into those tools. One question is 5 min enough time to live stack or should I do more?

Buck

2 things to look at here:

• alignment

• focus

For alignment:

• With the camera attached to the scope, turn on the reticule in SharpCap. Using a land based object (best before dark), ensure that the red dot finder and SharpCap view are both centred on the land based object. This alignment will help when you are carrying out the 3 star alignment.

• When performing the 3 star alignment turn on the reticule in SharpCap to help with accurate centring.

With an alt/az mount you will be able to get around 30 minutes of capture before field rotation starts to affect stacking.

For focusing, purchase a Bahtinov Mask (cost around $20) e.g. https://www.ebay.com/itm/284151172239

Have a read of pages 2 & 3 of viewtopic.php?t=2552. On page 2, I have my finder scope and telescope both centred on the top of the tower. Use Display Histogram Stretch if the light is failing. Page 3 has some settings to help with focusing.

If you are going to image M3, then use a nearby star for focus - Arturus or Alkaid might be good choices.

This all takes practice - time spent on alignment and focusing will reward you with better images. Expect it to take nights of trying to improve your skill levels. See my M42 Chronicles viewtopic.php?t=596

Dave

Hey guys,

Thanks to all for excellent comments. I had another go at M13, I did use the mask and it sure helped. The tracking was much better. Had issues with the polar alignment so I skipped. I used a tool called GIMP. I am improving and I love this live stacking option what a terrific way of getting pics. What was really cool I did not receive single dropped frame.

This is a better pic of M27, lots of green, will work on that lol.