PixInsight SpectroPhotometric Color Calibration: Part 1 (Astrometry)

[@AdamBlock]

Please really... watch Part 2 which is specific to SPCC and how it works: kzbin.info/www/bejne/rWnXl2CVnLp_irM

[@MrGuitar50]

Up next!

[@wadehustad9447]

Your approach and mindset to any module in PI is why you will always stand out for most astrophotographers. We are so grateful for what you do for the community!

[@AdamBlock]

Thank you Wade.

[@briankotak403]

Just starting to use PI. I am also relatively new to astrophotography. This was an excellent tutorial. I followed your steps on a OSC image of M31. Super pumped that the astrometric solution worked and the colour calibration worked. So cool. A real game changer! Dr. B from Manitoba, Canada.

[@garyrear]

Altona MB here 👍

[@wandaconde3696]

After a year away from the hobby, I am slowly (but surely) coming back. I am absolutely impressed about all the new tools that have been added over the past year. Your videos are invaluable for me to get up to speed. Thank you very much!

[@ariathyf144]

I'm not into the hobby but your presentation sounds very well done and I appreciate the work compiled there.

[@AdamBlock]

Wow... well thanks for watching! You have some good patience!

[@AdamBlock]

There is a part two if you want more... LOL

[@afryhover]

Thanks for video Adam, we really appreciate it. I look forward to using SPCC.

[@AdamBlock]

I just posted Part 2 kzbin.info/www/bejne/rWnXl2CVnLp_irM

[@deep_space_dave]

Wow another excellent video tutorial Adam. Can't wait for part 2!

[@tom886]

I was waiting for this, finally you released it. Awesome, thank you

[@AdamBlock]

Thank youu!

[@Spaced_Out_Bill]

Wow, this is an awesome video. Thank you!

[@AdamBlock]

Part 2 is better... will be released later today. Thank you.

[@bronco_fv]

Can't wait for part 2!

[@MrGuitar50]

Great video! I have 1 question. I probably missed something but, if you use WBPP to get an astr- solution does this mean you can forgo using the ImageSolver? Or do you just need to put the parameters (Ie focal length, etc) in the imagesolver process in advance of executing WBPP! Thx again!!

[@AdamBlock]

WBPP is using ImageSolver. You are correct that the values of a successful run of ImageSolver will be remembered next time- but in general you should have the correct values in your files (headers) before using WBPP and the plate solution and everything will go well.

[@monteroder2708]

Adam..when using an IDAS NBZ filter, what would I choose for the filter selection since IDAS is not a listed option

[@AstroHunter5280]

Adjusting the filter fields in SPCC: with the ASI533mc, sony sensor, should i be using the "CHROMA R/B/G" settings or should i be using the "Sony Color Sensor R/G/B" settings? Thank you!

[@pemongillo]

Thanks for the details on this. One thing you said really surprised me. I took your Intro to PI class last year. My notes and the ones I dowloaded from your site imply one does PCC before DBE. So now I'm confused.

[@AdamBlock]

I changed my opinion on that some time ago and noted this in my tutorials.

[@pemongillo]

@@AdamBlock PixInsight evolves very fast.

[@AdamBlock]

@@pemongillo Indeed... difficult to keep up lately.

[@krzysztofchmielewski9246]

Hi, Thank you for this video. I used APASS data to plate sovle my Image and then i used GAIA DR3/SP to to SPCC. Process went through without any errors in the console (not that I've noticed at least). My question is, is there any drawback for using APASS instead GAIA DR3 for plate solving the image before SPCC? Regarding the Image Plate Solver Script, I do drizzle x2 for my integrated images, so I always have to put focal Length x2 in this script, otherwise it fails. So instead using 250mm I have to use 500mm as a parameter. I've notice that you have not mention about this use case. thanks.

[@Rafastro]

Does this work on Narrowband images? I’ve never used photometric color calibration on narrowband.

[@AdamBlock]

It does... but maybe not the way people expect. This will output the TRUE line strengths of emission at the wavelengths of your filters. Of course, H-alpha will always dominate. So this will not adjust weaker channels (OIII and SII) to "balance" anything- but it will give you the true astrophysical relationship between these line strengths.

[@dr7615]

It is great to see just how many things PI is useful for. Question: So, if we have a situation where we use binning 2, then we should multiply our pixel size on the image sensor by 4 for an effective pixel size? That special number is also a slight round up of 1/tan(1/3600). Because my mind likes to know where these values come from, I use trig for many calculations.

[@AdamBlock]

If you bin 2x2 the *plate scale* will be doubled. It is the linear scale in each direction..not the area. 180/pi *3600 = 206265

[@paolospeggiorin1180]

Very interesting! I would like to know how much important is the correct choice of the parameters “QE curve” and the filter types. ANC in addition if I have removed IR filter from my SonyA7s, which choices must I choose? Thanks!

[@AdamBlock]

Please see Part 2 ..bot be released shortly.

[@jackmanatee3162]

Do you recommend the use of drizzle integration? If so, how does its scaling affect the use of image plate solver's arcseconds/pixel calculation?

[@AdamBlock]

I recommend drizzle without resampling for OSC data. This will taken care of interpolation artifacts and it will keep your plate scale the same. Resampling by drizzle (200%) will truly halve your plate scale "/pix. I am not currently a big fan of this because my results have not shown worthwile improvements.

[@jackmanatee3162]

@@AdamBlock Thanks for the great information. Can't wait to try SPCC out, but will need to wait for decent Internet access to get the GAIA data. Currently my rural bandwidth options are almost worse than a modem. But at least the skies are dark (Bortle 3/4)

[@gunterlist2999]

Hi Adam I have loaded GAIA, i have got an astronomic/plate solution successfully also shown in fits header. When i use SPCC i see in Process Console changing the white balance factors and final "done". But it doesn`t show me the graphic with the White Balance Functions. I have got the massage "Your file couldn`t be accessed it may have been moved, edited or deleted ERR_FILE_NOT_FOUND" I also have checked "Annotate Image" successfully. What`s wrong? Greetings Günter

[@AdamBlock]

You need to write this to the official PixInsight support form with screenshots.

[@kurtbauch5491]

I downloaded the appropriate files (Gaia DR3/SP) to my C drive (to my library files in PI) and when I open the Gaia process, the Star catalogues are not there. I don’t have a Star catalog as you do. What am I doing wrong? Thanks!

[@AdamBlock]

I am not certain I understand. When you first download the files they will go to your downloads directory (folder). You will need to move to a place on your machine you want them. It sounds like you have done this. Then when you open the GAIA process, you click on the wrench and first select GAIA DR3 and then navigate to the place on your computer they live and select them. Then you do it again for the GAIA DR3/SP filters after selecting it from the dropdown. Where are you stuck?

[@kurtbauch5491]

@@AdamBlock Okay, thanks. I didn’t understand the “Select” button. It worked! Like you stated that it was pretty simple (except for my 63 years old particularly fossilized brain, which hasn’t done any programming since college & my first class we were punching cards). Thanks again and I appreciate your quick response!

[@AdamBlock]

@@kurtbauch5491 LOL... Get that Trilobite to work in there! :)

[@txastro4453]

Any suggestions what to select for RGB filters for a stock (unmodified) Canon 750D? The available selections stop at the Canon 600D.

[@AdamBlock]

I seriously doubt the filters are significantly different. (it is probably the sensor that would be different if anything). You can click through the Canon filters..and see how similar they are. Just pick the last available version... should be fine.

[@txastro4453]

@@AdamBlock Thanks! Will check that out.

[@subashisamarasinghe1439]

Dear Adam, thanks for this very informative tutorial , please help me with the following problem , i use spcc for all my color calibrations till recently i had to reinstall my pixinsight, it got installed with everything except spcc and no clear way of updating it in pixinsight software distribution , your advice is highly appreciated.

[@AdamBlock]

Usually this means your "reinstall" is of an older version or the repository still points to the older version (even if you installed the newer one). See: www.adamblockstudios.com/articles/fix-missing-components-pixinsight-installation

[@subashisamarasinghe1439]

@@AdamBlock Hi, Adam, excellent advise, the repository was pointing to 1.8.9 -0 version -corrected, now ok, many thanks!

[@AdamBlock]

@@subashisamarasinghe1439 Great!

[@craigwallace6601]

An interesting 'quirk' with transferring image solutions from DBE only when 'replace target image' is used. Personally I replace as a matter of habit, but I notice most KZbinr tutorials rarely suggest to do this. I suggest this leads to a heap of errors for beginner users that would frustrate them when trying to use spcc!

[@AdamBlock]

Which is why I mention it... right? 27:00

[@AdamBlock]

Does this make me a rare KZbinr? 27:00

[@RaysAstrophotography]

@@AdamBlock I used to think you are kind of some old guy. You are very young Adam for the kind of experience you have and the work you are doing. LOL. Just some honest talk. No you are not a rare KZbinr. There are some crazy people here. You are welcome. Love your work and thanks for sharing

[@AdamBlock]

@@RaysAstrophotography I am becoming an old guy .. oh well.

[@msenin]

Where to get more filter definitions, such as Baader 3.5nm NB filters, for SPCC?

[@AdamBlock]

I suspect more filters will be included soon..but with respect to NB... for a given bandwidth (3.5)... I suspect most NB filters are going to have very similar specifications. You just input the bandwidth in the NB mode if you are using it this way.

[@msenin]

@@AdamBlock Right, I just figured it out: need to check the "Narrowband filter mode" box and then all it needs is wavelength and bandwidth. The only tricky part was that instead of using LRGBCombination to create SHO image, I used PixelMath with "R=SII, G=0.8*HA+0.2*SII, B=OIII", so instead of standard 656nm for HA/Green I had to interpolate the value.

[@montygiavelli8125]

Adam, When I tried SPCC on a stretched image I got an error message: "Robust linear regression (R/G): 0% Error: Insufficient data only 0 samples are available: at least 5 are required" With the image in the linear state SPCC finished without a problem. My image is SHO narrowband with ASI294MM pro 2x2 binning using Antlia 3nm filters. It looks like your image is stretched and SPCC finished without an error. Can you think of a reason why I got the error message ?? thanks, Monty

[@montygiavelli8125]

I think I just figured it out. I separately choose the GDR and the GDRSP in Gaia. I don't know why but it seems to work now ?? Monty

[@montygiavelli8125]

I spoke too soon, I'm still having the problem if the stretched image has been processed after the stretch !!?? Monty

[@AdamBlock]

@@montygiavelli8125 I think it is good you are having a problem on stretched images... when you use SPCC the images must be linear!

[@montygiavelli8125]

@@AdamBlock Thanks for your reply, but that's a problem for me. I don't combine the stars into the main image until the very last step after everything has been stretched. I can use SPCC on the Stars image in it's linear state but that only calibrates the stars. Does SPCC only work on stars or does it color calibrate nebulosity and galaxies !! I appreciate your help, Monty

[@AdamBlock]

@@montygiavelli8125 SPCC specially uses stars in the GAIA catalog and measures the SAME stars in your image. So yes, you need stars. I do not understand why you need to wait to run SPCC. I think you may have a misunderstanding. Run SPCC on the image when the stars in linear in a color image.

[@jesusbilbao]

What happened to Copy Coordinates Utility ?. Its not longer in Pixinsight Utilities.

[@AdamBlock]

Yes...it was deprecated. You can use the command line "cpast" to do the same.

[@kajouman]

Little question,when i have a target and a starless version like in your video about star de-emphasis,the result is just a starless version i tryd different settings with dilation etc,same result. Any ideas ? greetings John

[@AdamBlock]

It sounds like one of the images (the stars) is sitll linear.

[@kajouman]

@@AdamBlock ow,yes it is linear.. i could not see in the video iff it should or not. ill try again.

[@AdamBlock]

@@kajouman I got the right answer? Excellent!

[@johnadastra1754]

The Gaia DR3/SP files must also be selected and applied using the wrench in the Gaia process, or later when you go to use them in SPCC they will not be there to work with.

[@AdamBlock]

Correct.. you need to do both.

[@MegaMichaeltodd]

Does this differ from the photometric colour calibration that's been in Syril for years?

[@AdamBlock]

I am going to say yes without looking. The GAIA catalog- specifically the GAIA DR3/SP was only just recently released. Pixinsight is first as far as I know.

[@MegaMichaeltodd]

@@AdamBlock you can choose catalogue in Siril, Gaia being one I believe however I cannot speak to which version it uses. Happy to be corrected

[@comicbstudios]

@@MegaMichaeltodd siril is using a photometric catalogue and making assumptions about how that corresponds to the colour in your image (which will be somewhat inaccurate). Using a spectroscopic catalogue allows for that transform to be more accurate

[@AdamBlock]

@@MegaMichaeltodd That would be for the positions.. not the spectra. I am happy to be corrected.

[@wolfang4212]

Where do the asteroids files go and how to tell PI where they are ?

[@AdamBlock]

Watch THIS video: kzbin.info/www/bejne/Zl7MfIWeqcyKptk This directly answers your question. Consider subscribing and telling others about the channel. Join AdamBlockStudios.com

[@wolfang4212]

@@AdamBlock Thank you, sir! Subscribed.