Am I expecting too much from my DSLR

[Stuf1978]

I have been imaging with a Star Adventurer for the last 12-18 months and have just moved to a proper mount. Last night was the first time I've used it properly so decided to gather a bit of data on the Western Veil. My set up last night was as follows:

HEQ5 Pro

Evostar ED72 with OVL flattener

9x50 skywatcher guide scope with zwo asi 120mm mini

Canon 450D self modded fitted with a clip in Optolong L-eNhance.

I managed 48x300 second subs with darks, bias and flats. I'm in a bortle 8 zone and there was a 97% moon last night. I stacked in DSS and processed in photoshop.

I'm relatively happy with the final image with the exception of some horizontal banding that I've never really seen before. I did notice that that noise in my individual subs seemed to increase as the session went on so I'm assuming this is thermal noise? Baring in mind I only ever imaged up to 3 minute subs with the star adventurer so 5 minute subs are new to me. Am I expecting too much from this camera with regards to producing clean images at longer sub length? Or is my camera now my weakest link in my set up? I have a feeling it is but would like to get others opinions 😁

Thanks 

 

[Gerr]

Nice image of the Veil.

I had a go at the Western Veil too last night. Very similar set-up to you. Canon Rebel T4i modded. 48 lights of 210 second duration. Optilong dual band pass filter (Ha and OIII). Guided on HEQ5 Pro Mount using Evostar ED80 Refractor. Stacked in DSS. Processed in Photoshop CS2.

Not as much red in my image (but with a modded camera and filter I like to tune that channel down anyway as I sometimes feel it becomes too saturated). Hope you like too.

Gerr.

 

[alacant]

Hi. Well done for getting 5 minute frames under those conditions. Are you sure they were reasonable well exposed? 

I think the weak link isn't that you're using a dslr, but rather the noisy sensor of the dslr you're using. The 450 is showing its age these days. If you can get one of the more recent models with the18mp sensor, you'd notice a big improvement.

No exposure details, so I'm guessing that you used ISO 400, dithered between frames and stacked with a clipping algorithm without dark frames. If you didn't, there maybe something you could try. It may also help to go easier on the processing, stop before the noise gets out of hand?

But hey, it's working great:)

Cheers and HTH

Edited September 1, 2020 by alacant

[Pryce]

May I ask for the autosave file and I can see if I can get some stuff going in PS to clean it up?  

Won't post it anywhere of course. Only DM the final result to you 

 

[Stuf1978]

32 minutes ago, Gerr said:

Nice image of the Veil.

I had a go at the Western Veil too last night. Very similar set-up to you. Canon Rebel T4i modded. 48 lights of 210 second duration. Optilong dual band pass filter (Ha and OIII). Guided on HEQ5 Pro Mount using Evostar ED80 Refractor. Stacked in DSS. Processed in Photoshop CS2.

Not as much red in my image (but with a modded camera and filter I like to tune that channel down anyway as I sometimes feel it becomes too saturated). Hope you like too.

Gerr.

 

Nice image, yeah there is a lot of red comes through and it's hard to reign it in while also trying to bring out more of the subtle detail. 

29 minutes ago, alacant said:

Hi. Well done for getting 5 minute frames under those conditions. Are you sure they were reasonable well exposed? 

I think the weak link isn't that you're using a dslr, but rather the noisy sensor of the dslr you're using. The 450 is showing its age these days. If you can get one of the more recent models with the18mp sensor, you'd notice a big improvement.

No exposure details, so I'm guessing that you used ISO 400, dithered between frames and stacked with a clipping algorithm without dark frames. If you didn't, there maybe something you could try. It may also help to go easier on the processing, stop before the noise gets out of hand?

But hey, it's working great:)

Cheers and HTH

Yeah I bought the 450D as it was cheap and if I ballsed up the self mod I was only 80 quid out of pocket. Now I know it's really pretty straight forward I'd be confident in doing it again with a newer camera. 

ISO was 1600 which probably didn't help. No dithering as I'm still using an intervalometer to acquire my data. Guessing I should really be looking at alternatives for data acquisition that'll give me the option of dithering. Maybe APT? DSS stacking was just using the standard algorithm.

Thanks for that though it's give me a few things to think about 👍

18 minutes ago, Pryce said:

May I ask for the autosave file and I can see if I can get some stuff going in PS to clean it up?  

Won't post it anywhere of course. Only DM the final result to you 

 

DM me your email and I'll send a copy through 😁

[Stuf1978]

I've just reprocessed this image and realised the first was way way too aggressive, here it is

 

[ollypenrice]

That's much better and the processing, I'm sure, could further enhance the result. However, the Veil near full moon with an OSC camera really is a big ask!

You can dither manually with considerable advantage.

Olly

[Stuf1978]

13 minutes ago, ollypenrice said:

That's much better and the processing, I'm sure, could further enhance the result. However, the Veil near full moon with an OSC camera really is a big ask!

You can dither manually with considerable advantage.

Olly

Thanks, I've made this mistake before when I'm eager to process data that I've just acquired. Probably best to sit on the first process for a day or so and then go back to it with a more critical eye. 

I do realise that you can dither manually but it means staying outside in the cold lol. Think I need to hook the mount up to the laptop with EQMOD and use APT....... off to do some research 😂

[Pryce]

That looks much better! Similar result I ended up with.   Wasnt able to enchance the nebulosity further without blowing out the noise though

[Stuf1978]

43 minutes ago, Pryce said:

That looks much better! Similar result I ended up with.   Wasnt able to enchance the nebulosity further without blowing out the noise though

Thanks, yeah I think that's about as far it will go if I'm honest. Even ran it through starnet and still couldn't pull much more nebulosity out without bringing out the noise 

 

[Gerr]

Post-processing always a learning curve. There are always 'tweaks' and compromises to be had! 

I managed to learn a bit more about masks and colour channel levels to try and further improve my last image too:-

[Stuf1978]

1 hour ago, Gerr said:

Post-processing always a learning curve. There are always 'tweaks' and compromises to be had! 

I managed to learn a bit more about masks and colour channel levels to try and further improve my last image too:-

Nice one, looks great 👍 

It definitely is a learning curve, a steep one at that 😂

[Pryce]

Better have a lot of painkillers for those post-processing induced heahaches 🤣

But,  I also have to say that you're in a bortle 8 AND you imaged during a full moon,  so there's that. Not going to be optimal. 

Speaking of.  Are you using a light pollution filter? 

[Pompey Monkey]

What @ollypenrice said: dithering will really help you with the noise.

[PeterCPC]

+1 for dithering plus avoiding a bright Moon.

Peter

[Stuf1978]

8 hours ago, Pryce said:

Better have a lot of painkillers for those post-processing induced heahaches 🤣

But,  I also have to say that you're in a bortle 8 AND you imaged during a full moon,  so there's that. Not going to be optimal. 

Speaking of.  Are you using a light pollution filter? 

Yep, seems to be two steps forward and one step back. Was taken using an Optolong L-eNhance dual band filter. 

4 hours ago, Pompey Monkey said:

What @ollypenrice said: dithering will really help you with the noise.

Yeah, looking into running the mount with EQMOD and capturing data in APT so that I can dither automatically, don't fancy doing it manually.

1 hour ago, PeterCPC said:

+1 for dithering plus avoiding a bright Moon.

Peter

With all the cloud we have had in the North East over the past couple of months you have to take your opportunities when you can get them

[Adam J]

One more for dithering and not just a couple of pixels either nice big dithers of 50 or more pixels to combat banding. 

 

 

 

[Stuf1978]

Thanks all, I may need to start a new thread for this but how do I go about connecting the mount to a laptop and getting APT and PHD2 all talking to each other? 🤷‍♂️

[Rustang]

Ive just being doing all of this myself, what a headache!! Download EQMOD and EQASCOM, ASCOM for everything to talk to one another. If you can find my recent thread then there's lots of info that others have put that have good links to guides on 'how to', to follow! You can get an EQ DIR cable from FLO https://www.firstlightoptics.com/sky-watcher-mount-accessories/lynx-astro-ftdi-eqdir-usb-adapter-for-sky-watcher-eq5-pro-heq5-syntrek-pro-az-eq5-gt-az-eq6-gt-and-eq8-mounts.html  that connects the mount straight to the laptop, it goes in the hand controller socket, I currently go through the hand controller itself because I haven't brought that cable yet. It takes a bit of sorting out but as I know it will be worth it for better imaging. You will also need the ASCOM drivers for you guide camera extra to connect to PHD2 and APT.

Edited September 3, 2020 by Rustang

[Stuf1978]

5 minutes ago, Rustang said:

Ive just being doing all of this myself, what a headache!! Download EQMOD and EQASCOM, ASCOM for everything to talk to one another. If you can find my recent thread then there's lots of info that others have put that have good links to guides on 'how to', to follow! You can get an EQ DIR cable from FLO https://www.firstlightoptics.com/sky-watcher-mount-accessories/lynx-astro-ftdi-eqdir-usb-adapter-for-sky-watcher-eq5-pro-heq5-syntrek-pro-az-eq5-gt-az-eq6-gt-and-eq8-mounts.html  that connects the mount straight to the laptop, it goes in the hand controller socket, I currently go through the handset because I haven't brought that cable yet. Its takes a bit of sorting out but as i know it will be worth it for better imaging.

Thanks for the link. I'll also have a look in your thread 👍

What isn't a headache in the world of astrophotography 😂

[Rustang]

Here's the link to my thread, hope it helps 👍

Edited September 3, 2020 by Rustang

[Stuf1978]

21 minutes ago, Rustang said:

Here's the link to my thread, hope it helps 👍

Brilliant, thank you. Just ordered a cable from FLO 👍

Edited September 3, 2020 by Stuf1978

[jimjam11]

21 hours ago, ollypenrice said:

That's much better and the processing, I'm sure, could further enhance the result. However, the Veil near full moon with an OSC camera really is a big ask!

You can dither manually with considerable advantage.

Olly

The new star adventurer 2 is supposed to do unguided dithering which is super promising for something so portable...

[ollypenrice]

1 hour ago, jimjam11 said:

The new star adventurer 2 is supposed to do unguided dithering which is super promising for something so portable...

Worth looking into. Do you have a link?

Olly

[Hals]

I foolishly tried to image the Wizard Nebula during the recent 94% full Moon, DSLR even with a Quad band filter the result lots and lots of noise, likely caused by over-processing too. Plus I was a tad out of focus...It's a learning curve for sure, but a fun one.

Edited September 3, 2020 by Hals