Phillyo

I got mine from Amazon, these are the ones I got. https://www.amazon.co.uk/gp/product/B00JL4HGAI/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 I ended up stepping mine down to around F3.5 as I found that was a nice compromise between speed and sharpness of the stars. YMMV though.

3 hours ago, Limerick John said:

It was closed down to F2.8. The spikes are coming from the aperture blades.

Ah I thought so. I ended up buying step down rings that screw into the front of the lens to reduce the spikes, but that's personal preference I guess.

Lovely wide image. Was this taken wide open at F2 or stopped down a bit? It looks like there's diffraction spikes on some of the brighter stars.

Just wondering if anyone has seen or heard much about these mounts? I'm particularly interested in the WD17s. It's a servo harmonic drive, unlike the usual belt driven harmonic drives. Considering it as an upgrade to the EQ6-R Pro as it's much smaller and lighter with apparently fantastic tracking capabilities.

Phil

2 minutes ago, DanP-Astro said:

Thanks. I’ll have to do a moonlit/moonless comparison to see how much contrast/OIii I’m losing with my Altair 6nm filter.

Good luck with the lunar photography!

If you use pixinsight, use the SubframeSelector tool and check out the SNR change

2 hours ago, DanP-Astro said:

I’m still new to astrophotography but have recently upgraded from DLSR+lens to an IMX571-based camera and a Redcat 51. I’m not sure if you’ve considered it, but I’m really enjoying using a dual-narrowband filter on nights when the moon is bright, allowing me to take plenty of pictures of emission nebulae. I was surprised how many were perfectly sized for an APS-C sensor and the Redcat! Having used long camera lenses, the Redcat is too wide for my tastes for the moon.

I use an Antlia ALP-T 5nm dual band filter, but I still prefer to image when the moon is less than 50% because it massively washes out the contrast even with a narrowband filter. I lose a LOT of the OIII emission when the moon is high too, but thank you for your input

Good morning all,

So far I have only really done DSO imaging with my Redcat51 and my IMX571c camera, however with the huge moon blotting out the sky during the month (normally when it's clear too) I was wondering if there is a way I could image the moon with my current setup? I also have an ASI120mm mini if that is useful for lunar imaging? Can I buy any kind of barlow or adapter to connect my IMX571c camera to the redcat to give me a little more reach? I know the 571 doesn't have a very high frame rate but I don't really want to spend lots of money just to give something a try.

Any advice greatly appreciated.

Phil

I always do gradient removal first, then BlurX correct only, plate solve, SPCC, blurx, starx, noisex, GHS etc from there.

Awesome! I'll look forward to reading it if you ever get around to it.

Phil

16 minutes ago, Elp said:

I still use my Lextreme for OSC, don't really have a problem with it.

Regarding dual lens, if you can do it it's definitely worth it as I decided a while ago it had to be done due to the minimal opportunities to image. I've managed to get mine rigged so I can do the same target with both, imaging mono is suddenly so much faster in fewer sessions.

If it's ok with you, I might pick your brain (via DM) regarding your setup at some point in the future. I'll likely try and sort it over summer when I'm not imaging. I assume you've likely posted about it on this topic further back? If so I'll scroll back and see what I can find

Afternoon folks,

I'm getting a little tired of the amount of cloud cover we have in the UK, and whilst I love my little Redcat51...at F4.9 compared to the sammy it's a bit slow. So, I'm considering selling the Redcat and just going back to the Samyang lens for a bit and operating it at either F2 or 2.4 etc. to make the most of what (if any) clear skies we do get.

I currently use the Antlia ALP-T filter but it's the none fast version and I'm wondering if people know if the fast version from Antlia is still technically the 'best' suited or if anything else is better these days (L-Ultimate, or one of the new quad band filters perhaps?)

I'm also considering a second sammy at some point to run a dual rig in the hope I can double the light gathering or run it side by side for a wider FOV.

Thanks,

Phil.

29 minutes ago, tomato said:

A lovely deep M31. I must admit I fell foul of not reading the whole thread, I read the first reply and zoomed in on the stars and couldn't see anything wrong with them.

I got there in the end.

Sorry that's my mistake. I removed the first two images and just replaced them with the updated version. It looks a bit confusing now I guess 😕 

Good morning all,

Whenever I use Subframe selector to select the best subs to stack, I choose to output them into a new folder and they're all XISF file format. Then, when I preprocess them the usual way, the resulting image is just black with a few dots. Where am I going wrong?

Thanks,

Phil.

Another edit of this target, with added ha. Work in progress still! 

Here's my attempt. I tried a couple of different colour schemes but quite like this one.

This is BlurX on all 3 channels, then combined in NBcolormapper script with a palette I made. Then StarX, a small amount of NoiseX, stretching done with GHS on the starless image then stars separately. I added a touch on saturation with curves then combined the stars and starless image back together again. A small reduction in stars using the StarReduction script in Pixinsight and that's about it really.

Absolutely beautiful data to work with! It didn't require a lot of work to be honest.

Phil

On 13/11/2023 at 21:31, Stuart1971 said:

It’s a beautiful image, but not sure what’s happened to the stars….. any ideas…it’s all over the image

 

Tried another reprocess. The stars at the far corners are still showing a little coma I think, but looks a bit tighter perhaps?

52 minutes ago, Stuart1971 said:

It’s a beautiful image, but not sure what’s happened to the stars….. any ideas…it’s all over the image

 

I think I've pushed it too far. I'm trying new things with the edit but it's not working too well. I'll look again tomorrow 👍🏻

It's an old favourite but each year I like to try and better my previous years image. This year I managed to get out to a Bortle 3/4 area and collect about 9 1/2 hours of data in 60sec subs with my Risingcam IMX571c and Redcat51. I have lots of good data but I'm really struggling to do it justice! I'm going to approach this again and see if I can do better but trying to tame the core, get the colours right and also bring out the faint dust at the ends of the spirals is really very tricky! 

I've added the xisf also if anyone else wants to have a play with the data and share your result on this topic?

Phil

Try again!

Rather than make post about M31 I thought I'd just add another revision to this one, this time with added Ha data (Approx 6 hours only due to clouds).

Stunning image. A really tricky target to get right with the bright stars and very dim surrounding dust but you've done it justice there. I love a wider field of view with this target too.

Thank you both

A wide view of M33 taken with my Redcat 51 and Risingcam IMX571. I thought about cropping in tighter, but I actually quite like the wider look to it.

Only 4 hours of data due to the weather so I'm hoping I can add some Ha to it to make the areas pop a little more, weather permitting!

Phil

There's also the option of using Sharpcap Pro to do a sensor analysis, then using that data you can plug it it into NINA and use the optimum exposure calculator and it'll tell you what to aim for. I think mine was around 289 seconds so I just go with 300 sec (5min) subs. YMMV.

Phil

With newer CMOS sensors, more shorter subs are generally better than less longer subs. Gone are the days of old CCD 20-30min sub lengths due to the read noise. You only really need to do enough to swamp the read noise by a certain amount, then anything more is just collecting light pollution. There are other benefits of shorter subs like less requirement on the guiding/mount, more subs to integrate means better rejection of satellite trails and if rogue clouds pass over you only lose 5 min rather than 10 min of data for example.

There is the downside of more subs requiring a more powerful PC or longer preprocessing times. However, all that being said...astrophotography is a hobby (for most of us) and is there for our enjoyment. If you are getting the results you like and are enjoying what you're doing, then I would suggest carrying on with what you're doing as that's the moist important thing

Beautiful image! Curious as to why you're shooting 10min subs with the Redcat61 and the 2600mm? Or was this just an experiment to see if the AM5 could manage 10min subs?

Thank you both. I've done a slightly different version with a little less noise reduction and uploaded it up astrobin.com 

https://www.astrobin.com/full/mi9m07/0/