Adam1234

Incredible!

Hi all, thanks for the advice. I think I will most probably go down the PI route then. Sounds more of a learning curve (I do like learning things, gives me something to do on cloudy days, which is most days). but I'm sure the results will be worth it, and I do like the sound of all the post-processing capabilities.

Hi, I'm thinking of purchasing either PI or APP, but undecided which to go for, any advice? I'm sure this question has been asked before, but all the other threads I've come across mainly consists of people who only use one or the other arguing over which is better without providing much objective evidence, pro's/cons of each etc.

For anyone that have used both: 

• What are the pro & cons of each?
• What does PI offer things that APP doesn't and vice versa?
• Which ultimately results in the best image from a given set of data? 

I would download the trial version of PI to try out side by side with APP, but I got a trial licence a while ago which I didn't end of using. I've asked PI if it's possible to get  a 2nd trial but had no response.

Cheers

Adam

Incredible 

I find CO is more accurate than BBC weather most of the time,  but find neither are very accurate more than a few days in advance. 

Sometimes neither (particularly BBC) are very accurate even on the day. The other day BBC said the sky was clear - I looked outside but the whole sky was covered with cloud. Days in advance I can understand getting slightly wrong as there are many variables in the weather, but the current weather, I cannot understand how they can get that wrong! CO however was giving more realistic data.

That's incredible 

I personally found this one quite a difficult target to get a result I was happy with, so here's one last attempt, this time in HOO, processed and displayed slightly differently. 

Adam

Here's another SHO version, processed in photoshop.

Adam

54 minutes ago, tooth_dr said:

Great job I like that. 

Thanks! Glad you like it!

Just now, simmo39 said:

V nice.

Thanks!

Was there supposed to be an image here?

10 minutes ago, geordie85 said:

Your blue stars are slightly green (or it may just be my phone) other than that you've got a very nice image there 

Thanks!

Just looking at the stars again, hard to decide if they are on the green side or not, I ran HVLG (high setting) but I guess it could have missed a bit

Here's my rendition of the Crescent Nebula NGC6888 in HaRGB. 

1.5hr each of R,G&B (90 x 60s subs) and about 5 hours of Ha, captured using ZWO ASI1600mm pro with SW ED80 DS Pro. Inages captured with APT, stacked in Siril with darks, flats and flat darks, processed in PS.

Each channel stretched separately, then combined in PS to make RGB image, followed by Siril's photometric colour calibration. Starless Ha added to Red channel with blend mode lighten.

HaR also added as a luminosity layer, followed by some final stretches and selective colour and vibrance/saturation tweaks.

Hope you like. Any feedback/constructive criticism is welcome!

Adam

+1 for platesolving! I got into platesolving using APT earlier this year, really don't know what I would do without it!  Used to spend ages trying to get my target centred before platesolving (move it a bit this way, bit that way, no way too far, back that way, too far that way now, back the other way again...), difficult enough on a bright target yet alone a dim target. Now it takes seconds!

1 hour ago, Merlin66 said:

Always better to calibrate on a star closer to the equator.

PHD will then make corrections for the dec of the target.

 

I'm assuming you mean the celestial equator, rather than the actual equator?

Quite possibly your polar alignment is a bit off

Thanks for all your responses, that's helped alot and given me the info I needed! 

1 hour ago, ollypenrice said:

You can add OIII to both green and blue channels, too.

Thanks for that tip, I was wondering whether you could do that and was going to ask that question next, now I don't need too 😀

Thanks!

Brill thanks!  I got a couple hours of Ha on the Crescent, might get some more tomorrow then. 

So Ha better as luminance for emission nebula what about other nebula like planetary/reflection etc?

Either way, I think I'm stopping with the Crescent tonight, its going to be getting too close to the street light soon, and my guiding seems to be playing up for some reason 

Hi all, I had a question on luminance sub frames. 

So I've currently got 90 x 60s (total 90 minutes) sub frames each of R, G and B (of the Crescent Nebula if anyone interested). I'm now taking some luminance subs - should I go 90 mins total to equal each of the R, G and B, or 270 mins total to equal the total RGB?

Cheers

Adam

Hi Brendan, the reason it is timing out after 3 minutes is because your dithering timeout is set to 180s (3min), this isn't obviously the reason for your issue, this just tells the software how long to wait before giving up.

Looking at your settings, it may be the dithering distance and dithering stability set too high. A larger distance will take longer, and it may be that mount is struggling to settle. 

Not 100% though. If it helps, in APT I have dithering distance as 5, stability 0.7 (I think) and timeout 60s. 

Adam

9 minutes ago, Andy R said:

Nina is free you can use Nina and apt to focus alongside each other as shown in astroquest1 video

Sgp has a free version, I gunk, with limited functionality.  Good luck with the wind 

Thanks I'll give that a watch and investigate NINA at some point soon.

RE the wind,  I'm doing 600s exposures and they look to be coming out ok to me! I think the houses across the street and the garden hedge act as a slight wind breaker.

Feels like the wind has dropped a bit since I first took the scope out too. 

Either way, I'm glad I took the scope out. I'll give it another half hour or so then call it a night. By about 23:30 the streetlight on the corner will be getting in the way, but I will have about 3.5 hr worth of subs by then.

Lovely image! Good detail and colour. 

Here's my image of the heart ❤️ 

😂😂

44 minutes ago, Starflyer said:

I'm not sure how autofocusing works in APT.  SGP, NINA etc generate a focus curve Like this, the shape of the curve can help diagnose what isn't working properly.

I may investigate SGP and NINA at some point, are these paid for software?

3 minutes ago, Starflyer said:

Best to try and fix it in the longterm, autofocus isn't just about getting you best focus at the start of a session, it's about keeping you in focus as the temperature drops.

With my frac I need to refocus every 1.5°C temp drop or the focus shifts noticeably. Even at this time of year it can drop a good few degrees in the first couple of hours.

What software are you using, maybe you can post up pics of a V curve or two?

Hopefully I can get it working eventually. I hopefully just need to get the correct threshold, fine and course focus settings sorted perhaps.

I'm using APT, I haven't seen anything in there about V curve so not sure if it gives us the curve