Anthonyexmouth

23 minutes ago, bomberbaz said:

I run 15 second subs from my garden due to the conditions, very light polluted, so even with 5 hours data it is an awful lot of space I need. The time is reflected too of this. On M97 I gathered 1450 subs at 39MB each (that is 55GB), thats a lot of registering, stacking then kappa clipping, takes forever. 

If I drizzle which I have had occasion to do then obviously even more space needed and time of course. 

14 hours still seems like an awfully long time. but I don't use DSS so maybe that's the right amount of time. 

Is there any difference in output for image stacking in batches?

say 1. 100 subs stacked together 

2. 2 batches of 50 or 10 of 10 that are then all stacked together. 

On 24/02/2023 at 23:50, bomberbaz said:

I decided to stick all my data processing / imaging stuff on one disk drive of my PC. It's high end is said PC, Ryzen (12 core) processor, 32GB memory, and only 2xSolid state drives (SSD) until yesterday.

I had bought a 8TB (that's 8000 Gigabyte for the pc noobs) hard disk drive (HDD) with the intention of isolating imaging to help simplify things, seemed a rationale approach. I had considered speed but didn't think it would be as impacting as it actually was/is!

So anyway I had also decided to use the 8TB HDD disk as the temporary folder for DSS, then I set a stacking operation going and 14 hours later it finished. I was a little surprised at that time and so decided to run a side by side with some other data comparing HDD and SSD speeds.

M97 (not that it matters) was the data.  I tried it again using the HDD and it was stacked in 7 hours and 40 minutes. I then simply switched the temporary folder in DSS to my SSD drive and ran the same stack, no changes. The time1 hour and 40 minutes 😲

So if you use a PC for processing (or similar updateable equipment), just bear this in mind next update you plan. A word of warning that SSD's are quite expensive but can offer some considerable advantages in terms of speed as I can testify too.

 

How many and what size images were you stacking? I store all my subs on a very old sparc 4 drive ReadyNas . I direct WBPP to those drive for all the subs and calibration frames. My PC is a Ryzen 5700g with 64gb ram and I just stacked nearly 500 subs in and hour and a half. 

Ok, is this an artifact of my clumsy processing or flats not working or something else? When I remove the stars I see these circles. It does kinda show if I play with the HTF in pix too but only if i tweak it right. ASI fits viewer shows my dirty image train, I think this is close to the sensor or maybe on the sensor with the stripy bits. Pixinsight stretched flat doesnt show it. Anyway, am I trying to solve a problem that isn't there? I take it WPBB stacks and rotates pre-post flip before flats. 

Anyway, here's what I mean.

4 minutes ago, Xilman said:

First thing I always look for in images of M31 is the clarity of the stars. The first star is generally AE And, which is a LBV (luminous blue variable) star in the galaxy. It has been on my observing program for years and so can spot the region at a glance. Another LBV, AF And is also on the program.

By this metric the lower image is superior but both are good.

Here are the locations of the two variables on your image, with a zoom factor of 4 so that individual pixels can be seen. Note that AE And is markedly fainter than AF And, which is in line with my recent measurements. AE And was at V=17.52 and AF And at V=16.14 on 2023-01-24.0.  I guess your limiting magnitude is around 18.0 to 18.2.

 

AE And:              AF And:   

 

 

This is data from around Oct last year if that makes a difference. 

Had another play and came up with these 2. Still not happy and got a headache overloading on youtube tutorials. 

On 09/02/2023 at 10:48, Budgie1 said:

No, I think you would have to run the whole stacking process again, using all the subs & calibration frames + changing the Calibration Exposure Tolerance.

If you want to use the four stacks you already have then try the Image Integration tool under Processes. 

Update, when I tried to restack changing the tolerance to group them it seems to only be using one master dark, the longest exposure one, is this a problem or is it actually going to use all the right darks? 

1 hour ago, old_eyes said:

I may have misunderstood what you are trying to achieve, but why not use HDRComposition? That tool is designed for this job. It takes stacked images of different exposures and creates a high dynamic range version that allows you to see the detail from the long exposures whilst not having the bright core of objects burnt out. A standard approach for objects like M42 and M45. 

it is simple to use, and the tool works out which order to stack the images for the best result.

I'll take a look at that. 

12 hours ago, Elbasso said:

That is some quality data you've got there!

Could you share a few details on the gear you've used? 

Stellar Mira 90 triplet , 294mc and a skytech l pro max filter

10 minutes ago, Simon Pepper said:

Hope you do not mind I had a quick go at this. See below and steps I just took. I think it could have done with a little more DBE but I like it! 

• SCNR removed green
• Inverted image and repeated SCNR green
• Range masked the core and pulled down the curve 
• Range selection again more aggressive in the core pulled down curve
• NoiseXterminator 0.4 and 0.1
• Histogram transformation on each colour channel to balance them out this knocked out a lot of the blue

This  is good data and the core of M31 is bright as we know is it even possible to not blow it out to an extent? Oh and I 180 flipped it as any other way I see it as upside down which is stupid as there is no up in space  

 

Well that's looking better. It's only about 7 hours data. 144x3min I've got another 13 hours sitting on the NAS waiting in 60s and 240s subs. 

So you adjusted the core before stretching? 

37 minutes ago, ONIKKINEN said:

What kind of curves and what does the image look like if you dont do the curves but just do a simple stretch after SPCC?

I'll post it tomorrow. 

5 minutes ago, ONIKKINEN said:

What did you do to make it so cyan? Have you tried colour calibrating with SPCC, it churns out a well balanced image every time.

Unfortunately my PI trial ran out and my bank account balance disagrees on the importance of buying the software so cant run it through now, but i am sure SPCC would not make it so cyan. The problem there is that the colour palette becomes quite boring and you'll have to selectively boost the blues quite a bit in case you wanted a typical neutral looking core and blue outer regions with red Ha poking out here and there. In that case you dont want to apply saturation globally, you want to avoid adding much yellow/orange saturation or the core becomes deep fried but instead apply saturation to the bluer and redder (Ha) parts of the image.

On a side note, the image is way too big at 8k pixels in the wider axis which is also why the file size is ridiculous. You can safely at least bin x2, probably more, and lose nothing of value. Also helps a lot with your noise (only noise seems to exist in single pixel level detail).

All i've done is a SPCC calibration, stretch and slight curves. 

Here's the raw stack. 

M31 stack.xisf

Pixinsight is a bit of a love hate thing for me. My fault for not processing more often. I get the hang of something then forget what I've done. Now I'm having one of my can't remember days and can't get M31 right. Getting too much cyan in the outer region and blown out core. Anyone wanna give me a poke in the right direction. 

Here's my problem image in tiff format, I'll post the raw stack and alt version in the next post because of file size limits. 

M31 too cyan.tif

17 minutes ago, ollypenrice said:

I use an ink tank Epson 15000. The bottled inks are really not expensive and go a very long way. It can print up to extended A3 and, although it's only a 4-ink machine, I find the prints to be excellent - and I'm fussy. Because I can do a small test print first, this beats hoping for the best with a third party service.

Olly

I've got an older canon pixma mg6350 6 cartridge printer. Never tried photo printing with it though. Maybe I should, any recommendations for paper? Advertised spec is

• Print/Scan/Copy.
• Up to 15ipm Mono Print.
• 9600 x 2400 dpi Print.
• Up to 10ipm Colour Print.

13 minutes ago, ollypenrice said:

Start with your unreduced, processed final TIFF in Photoshop. Use the crop tool to set the proportions you want to end up with, so 12x16. (This crops to a proportion, not to a final size.)

Go to image, size and uncheck resample.

Set the dimensions to cm or mm, not pixels. Set these dimensions in the appropriate boxes.

See what PPI value this gives you. It's shown on the screen.

If it's enough for the printer, fine. It should be.

If it's not, check resample and next to that choose Preserve Details (enlargement.)

Type in the PPI you want.

 

The other thing to remember is the colourspace. The printer needs to know which one you are using. The internet standard is sRGB but it isn't the best to work in. I process in ProphotoRGB and print from that but, for the net, I go to Edit-Convert to Profile (note, not Assign Profile) and choose sRGB if that's what the printer wants. If you're not sure what colourspace you're using in Ps, go to Edit - Colour Settings and see what colourspace is there in your working spaces. It should be OK just to tell the printer what you're using.

It's always best to do a small test print first because, with the best efforts in the world, getting the screen and the paper to match up is not dead easy!

Olly

 

That's all sounding like really great advice, but alas, I don't have Photoshop. Although I might have an older pooched copy laying around on the nas. Just couldn't bring myself to pay for the subscription. I don't have much experience with it anyway, played around with lightroom a bit but can't remember any of it. 

That all makes good sense. So definitely nothing to worry about with my images then for wall hanging. So far I've only printed a few with a 6x4 canon selphy printer. They churn out a nice print but craving something bigger now. 

Cool. So no issues with the size I wanted. 

Is high quality home printing really viable on a budget at that size? Or is print shop the best way? 

5 minutes ago, Lee_P said:

DPI is dots per inch. You can change an image's DPI in software like Photoshop. If you're not sure how, feel free to send me your image and I can do it for you. Your camera is certainly capable of producing 12x16" prints 👍

Oh I get what DPI means, doesn't it just decrease the bigger the image gets printed? Why does windows report it as 72dpi. why not just report the pixel resolution? 

Popped into a local printer today. Thinking about getting the odd nice image printed. I pointed to a print size of 12x16 as the kind of size I was looking for. He said the image would ideally be 300dpi but at least 150dpi, now I've just looked at a tiff save from Pixinsight and it seems to be 72dpi. Am I reading it wrong? Is my 11mp 294 not capable of a print that size? 

Never done any serious photo printing so unsure on this one. 

9 hours ago, jacko61 said:

Out of interest, what does NINA give you (or improve on) that APT doesn't?

Graeme

So much more control. More intuitive layout. The nice thing about it is the way it can be as simple or as complicated as you want. It'll grow with you where you could easily outgrow apt. It's also free. I used apt for about 5 years. It's good but I'd recommend anyone starting from scratch to go straight into NINA. It has lots of really useful plugins that can polar align, analyse images for tilt. Upload subs to lightbucket which is really nice for easily checking subs during a session from your phone. So very many things. Check out patriot astro on YouTube, he has excellent tutorials from setting up for the first time to advanced sequencing. 

I used APT for years and held off switching to NINA because I was used to APT. I so wish I'd switched much sooner. It looks daunting but it can be as simple or sophisticated as you make it. If you're just starting I'd say jump straight in to NINA. Patriot Astro on youtube has excellent tutorials. 

I use a click lock on my ED80, probably adds about 20-25mm, the 2" nose slides in. As long as when you focus now there is more than 25mm draw tube visible you should be ok. 

17 minutes ago, Neil Wilson said:

Just checked Anthony. Nothing's changed.

Both in eqmod and in device manager? 

53 minutes ago, Neil Wilson said:

Hi Anthony, 

I don't use a WiFi dongle. I connect using a USB to RJ45 cable. Downloaded the latest Synscan app with no joy.

Has the new firmware maybe changed the Eqmod com port?