Phillyo

I don't have that exact set up, but I use the Risingcam IMX571 which I think is the same or similar sensor with the Samyang. I shoot at f3.5 using stop down rings and for narrowband (5nm Antlia ALP-T filter) I shoot 3min exposures as directed by NINA exposure calculator having done a sensor analysis in Sharpcap Pro. I don't mess with the gain or offset and leave them at default.

NINA will be debayering and performing a stretch on your image, so it's a useful guide but don't look into it too much. As you say, you need to stack them and check them fully in PI before really getting an idea.

For broadband I can shoot as short as 5 seconds in my area, but obviously that would fill my hard drive way too quick so I normally shoot 30, 60 or 120s exposures depending on the brightness of the target I'm aiming for.

I live in a Bortle 4/5 area for reference.

On 23/10/2022 at 11:30, Gonzo said:

The ZWO OAG fits nicely, untested as my Player-one Uranus-c hasn't arrived yet (next week).

Where do you place the filter in this imaging train? Looks nice and tidy though!

Thank you  I do like this set up lol, very easy to get good results. Though I am considering getting an actual telescope soon, not too sure what yet though. That'll probably make things more interesting!!

I have reprocessed this image again from the original stacked XSIF file, hence the slight colour difference to the one I posted above. This time I haven't used any noise reduction at all, and I don't think it needs it really. It's a very clean image. Does that look a little less plasticky @Stuart1971 Still learning!

Phil

2 minutes ago, Stuart1971 said:

Lovely image, but I agree with @Shibby overdone with the noise reduction, has left the focus a bit too soft, and also made the image look a tad plasticky for my taste….

Thank you both for the feedback. Always looking to improve with processing. I'll take another look this weekend and see if I can bring back some detail and tone down the noise reduction a bit. I might drizzle the data too, see if I can get some more detail from the image.

Thank you,

Capture equipment is in my signature  details are around 8 hours or so in 3 min subs I think? I can never remember lol. I'll take another look at the noise reduction, to be fair I did it quite quickly as I was just happy to be editing some data so probably overdid it slightly. I didn't think the noise reduction was that heavy, I think the detail is possibly lost because I'm imaging at a scale of around 6"/pixel with my IMX571 and Samyang combo? But I could be wrong. I'm very heavily under sampled.

Phil

I've reprocessed this with some new techniques and using good calibration data. It has already been uploaded to the dedicated Samyang topic, but thought I'd share it here. 

After spending most of the day sorting out a calibration issue (thank you @ONIKKINEN) I've had chance to reprocess some data with the right calibration files and man what a difference lol. This is the heart and soul neb, about 8 1/2 hours of data I think. Still learning pixinsight, but definitely happier working with better data. Onwards and upwards!

Yeah one of the rings completely snapped? Hopefully it'll be ok for you

I used this for a while but it ended up snapping which was disappointing. I ended up buying the autofocus kit from Astrodymium (spelling?) and now use a ZWO EAF with it. Seems a little better made than the astrokraken one I bought, but yours looks a little different to mine so perhaps they've updated/upgraded it slightly? It worked well for a while though!

1 minute ago, ONIKKINEN said:

I wonder if your mini-pc on its last legs dying caused the failed subs with banding? That issue is still a mystery and i would say unrelated to lightleaks and temperature issues so the main problem could still be ahead. I guess you will find that out with a new one.

I was thinking/hoping that might be the case. New one has been ordered, slightly better spec than the old U55 (I've gone with a Beelink U59) so hopefully that'll solve the final issues. It'll be here in 3-10 days so just gotta wait now

Thanks again.

Updated version of the California Neb. Much happier with this now  thank you.

So far so good. The image seems to be MUCH better corrected now. I've only used 10 x 3 min darks but just wanted to give it a go. Now I just need a new mini PC to control everything and I can get it back outside to see if I can gather more data and see if the issue is fully resolved. Thank you everyone, especially @ONIKKINEN for the help, very much appreciated!! Definitely owe you a beer

Phil

1 hour ago, Budgie1 said:

What's the amp rating on the PSU you're using?

A 5 amp PSU should normally be fine but the Pegasus PSU for the PPBA is rated at 10 amps max. 

If you use the app for the PPBA, you can monitor the output with everything connected and see what it peaks at.  

https://smile.amazon.co.uk/gp/product/B01579KBFW/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

It's rated for 10A. I probably need to keep an eye on that as I do use the app, I just forget to check it lol.

Slightly off topic, but as I am just using the camera off the telescope (lens) I'm using the supplied AC to DC adapter that came with the camera to power the cooler. I've noticed that the variation in temperature between the frames has been TINY compared to variation in temperature when everything is powered via the Pegasus Pocket Powerbox Advanced Gen2. Is that normal? I thought for a rather expensive bit of kit it would regulate the power going to the camera/cooler better than that? PPAv2 is powered by an AC to DC 12v regulated power supply too, not via a battery. I'm now wondering if it might be the PPAv2 that's causing issues with the random bad frames? More investigation needed, frustratingly! But, one thing at a time. I'll work on this first

I've installed everything onto my desktop PC (wow it runs NINA so much faster than my mini pc lol) and I'm currently doing flats, darkflats and darks.

I decided to have a look at all the darks and darkflats I had through Pixinsight's Blink function, and you are right. It is very obvious there's a vignette on the darks and darkflats. Having had a look at the 50 darkflats I've done so far, they look so much cleaner now that the camera is off the lens and has the lens cap in front of the sensor. No light leak. Fingers crossed this makes a difference!!

I'll update again later when I have a full library for 180s darks to calibrate my images with. Fingers crossed!

Phil

Quick update, my mini pc has just died sooooo it'll have to wait

I will give that a try today and let you know how it goes. Thank you. 

I was under the impression that flats didn't need to be at the same temperature as the lights? Obviously I got that wrong somewhere! 

Thanks again. I will post again with updates 🙂👍🏻

Phil 

There you go, hope that helps!!

Thank you.

Light.fits darkflat.fits Flat.fits Dark_180.fits

5 minutes ago, ONIKKINEN said:

Hmm, same offset, gain, temperature and still no working flats. Something doesn't add up. I was thinking if your dark flats have a lower offset than your darks for some reason you would get undercorrection. The overcorrection without darks is right, because offset is not removed in that case.

And also, i dont have PI (yet) and so cant open .xisf files.

Could you upload one of each file, darkflat, flat, dark, light in 16-bit .TIF or .FITS format? Not sure i can help if everything is correct but cant hurt to have a look?

Ah, fits! Sorry, misread that. Yeah I'll do that in a sec. Thank you.

Thank you for your reply.

Just to confirm, my Lights, Flats and Darks are all taken with the same driver (native Risingcam driver in NINA), the same offset and gain, HCG etc. Lights and darks are 180s long, both at -10. Flats and dark flats are around 3.17 seconds long, but at normal temperature. I've tried flats at 50% and 33% of ADU using NINA flat wizard.

Attached is a single flat and light (both calibrated). I'm using WBPP in pixinsight for everything.

Not sure if it's related, but if I calibrate/stack everything without using the dark frames then the flat frames overcorrect and I get white corners in the image. When I use the 3min darks that doesn't happen, but then I don't get the vignette removal?

Thanks,

Phil.

0006_3.17_24.400.00_c.xisf 0000_180.00_-10.300.85_c.xisf

6 hours ago, Ratlet said:

What is the first image you have posted, the one with the banding?

I've had weird halos on images, once was caused by an issue with my flats, the other was ABE.

For the flats I'm not sure the issue but it seems to have been sorted by going dimmer therefore making the flat exposures longer.  I also use the flat panel wizard on Nina.

This showed up on the images before automatic background extraction.

With the ABE there is a bit underinterpolation and output for function degree that defaults to 4. Try setting it to 1 as I've found leaving it on default can cause some weirdness.

 

Edit:. Just worked out the first one is the frame with the banding. 

 

What does your master dark look like if you apply an autostretch to it?

 

I've tried that but it made no difference.

I'm more worried that the flats aren't removing the vignette, and the random bad frames in the middle of an imaging session for no reason. I'm a little worried I've bought a dud camera

Thank you for the reply.

Phil

So I'm still having some interesting issues with this camera that I can't figure out. I have created a post over on the Risingcam AP Facebook page so I'll copy and paste that here with image examples and hopefully someone can point me in the direction of where I'm going wrong!

"Good afternoon,
I'm having some issues with my Risingcam (colour) camera and wondering if anyone can help. I'm imaging through the Antlia ALP-T 5nm filter and a Samyang 135mm lens stopped down to around f3.5 using stop down rings. I'm getting really bad vignetting, even after using flats, dark flats and darks. The image is also very noisy and after I run ABE/DBE (to deal with the vignetting) I get a halo ring type effect around the middle of the image.
I have the dew heater on and I have dew straps around the lens (and guide scope) and I've checked during the night and there's no dew forming that I can see. I'm using NINA with the native Risingcam drivers. Eddie from Risingcam has suggested I try the Ascom drivers to see if that helps? Also, during the night I'll have a bunch of frames that are just white/grey with no detail and lots of banding lines across like the sensor has just messed up. Maybe 3 or 4 from 100 or so images but for no apparent reason.
I'll upload some images as examples to this post to hopefully show my issues.

Finally, I did a sensor analysis of the camera using Sharpcap, but I noticed that even doing that analysis with the camera/sensor directly on top of my white panel and no lens in the way I'm seeing vignetting in the image. Is that normal?
Thanks for any help and sorry for the long post!"

I have attached the 'bad frame', the vignetting from the sensor, a master flat and the resulting image that has only had background neutralisation and colour calibration before being stretched to remove the green element from the RGGB sensor. This is approx 6 hours of data I believe.
Phil

On 10/10/2022 at 15:05, wvrfish said:

Sorry to resurrect this thread again... but I had a question about fixing a flanged pier down:

How do you ensure the pier sits plumb when bolting it down? In my limited experience with concrete, it is never particularly level nor flat.

Or do you not worry to much about it and rely on the top plate to get a level surface for the mount?

Thanks

It wouldn't need to be perfectly level, 'close enough' is close enough.

15 hours ago, 900SL said:

On this subject.. I currently have an IDAS NBZ dual band filter on my 533MCP. I think this is around 12nm. Would I see an appreciable difference changing to an Antlia ALP-T dual band at 5nm? Bortle 6 ish skies...

I'm assuming I'd have cleaner frames and a better S/N but wondering how big a difference it would make quantitively

I went from the IDAS NBX (precursor to the NBZ I think?) to the ALP-T filter on my Samyang at f3.5 and the contrast in the images is indeed more noticeable. Whether it's worth the extra cost is of course entirely up to you.