LRGB vs RGB - Which is the BEST?

In this video I perform a little experiment with some test data I was capturing on m63 the sunflower galaxy.
I wanted to know if LRGB or simply RGB was better from my location here in bortle 7 skies.
There's arguments for both sides online, but it seems like there's often no "one size fits all" answer for it!
So, I want to find out for myself once and for all, which is actually better? LRGB or RGB?
/ lukomatico
AFFILIATE LINKS!!
Topaz Denoise, Gigapixel & Sharpen AI are some of my favorite software to aid in astro processing! If you buy the software through this link I would receive a commission at zero extra cost to yourself!
Topaz Labs Affiliate Link! - topazlabs.com/ref/1133/
Topaz Labs Discount Code for my viewers! - FRIEND15
My new Mini PC for imaging! Amazon Affiliate Links! - Anything you buy through one of these links will give me a small commission at no extra cost to yourself!
Amazon UK - amzn.to/3EOCgpV
Amazon US - amzn.to/3quGPlD
High Point Scientific Affiliate Links!
High Point Scientific Affiliate Link - www.highpointscientific.com/?...
Orion Telescopes & Binoculars Affiliate links!
www.pjatr.com/t/R0FHSUdKTEFGS...
www.pntrs.com/t/S0BMQ0pFQEVHR...
www.pntrs.com/t/R0JJSEVIS0ZCR...

[@paulbenoit249]

I love this type of comparison, it really helps to decide the best way forward to improve on one's image. In order to get the same definition of conventional mono (LRGB), I decided to go the dual camera route (less filters, no filter wheel, easier picture taking protocol and processing): color camera for the color, mono camera for the luminace (or Ha in some cases).

[@lukomatico]

Thank you my friend! The dual camera route is a great way to do it I think - good on ya! 👍 Clear skies

[@azrayastrophotography2260]

Thanks for the great video comparing the different processing. I am still learning new skills. I really enjoy your videos.

[@lukomatico]

Thank you so much for watching and leaving a kind comment Ray! Clear skies my friend :-)

[@Lasserubinskov]

Super interesting as always. I love your channel and your work.

[@lukomatico]

That's so nice of you to say my friend, thank you!! :-) Clear skies!

[@michaeledmonds3027]

Thanks for the great video. Was interesting seeing your mates setting up as you started.

[@lukomatico]

Thank you Michael!! It ended up being quite a cool effect as the footage overlapped haha!! I'm glad it looked OK! 👍👍 Thank you for watching!

[@bloodsthicker5651]

I look forward to future endeavours, nicely done. That end image though! 😊

[@lukomatico]

Thank you so much my friend!! - I was really happy how it turned out for relatively little time under a quite moonlit sky! really a promising result from this big newt :-) Thanks for watching!

[@montymcneilly]

Great stuff Luke, keep up the great work!

[@lukomatico]

Thank you so much mate!! :-D clear skies!

[@joakimastro]

Cool experiment, watching over a beer while imaging the Cone Nebula!

[@lukomatico]

Awesome to hear it mate!! :-D Hope you are enjoying capturing the cone! (and enjoyed that beer too I hope!) Clear skies dude!

[@AstroSoundscape]

Hey Luke - That was an interesting comparison mate, really well explained as always. Like you said looked like the first one was the winner there.

[@lukomatico]

Thank you Ollie mate!! - Aye it seems like LRGB pulled ahead a decent amount! - I'll have to test LRGB vs OSC next I guess! Should be interesting if nothing else! :-) P.S - I'm so sorry I've not caught up on your recent vids yet bro, I am going to do a big catch up soon haha! just been swamped lately, what a crazy few weeks! All the best man!

[@AstroSoundscape]

@@lukomatico Hey all good pal don't worry about that, I know we all have lives beyond KZbin too!

[@jonbasstro1413]

Hi Luke, great experiment you carried out.I don’t own a mono camera,however,it was good to see the possibilities available compared to what OSC offers.Another fantastic final image you produced for the start of galaxy season.Clear skies!

[@lukomatico]

Thank you Jon! - Ah mate it was a lot of fun to turn a little experiment into something sharable, I'm so glad it was ok to watch! :-) I too still love OSC and really truthfully see the merit in it, you get very comparable results overall to mono but with a LOT less hassle! :-) Thanks for watching mate!

[@jonbasstro1413]

@@lukomatico Yeah I agree, even though the results look great with mono, I can see the hassle in doing mono seems to be quite a bit down the road for me, and with your tutorials it shows you can go down the Hubble Palette route with a OSC as another option.l’ll be sticking to DSLR and OSC.Clear skies!

[@GarnettLeary]

Saw this and immediately shut off the tele, went to a quiet place, and fetched a drink. I love mono. Recently switched to mono for planetary as well. I’ve gotten so bogged by intrusive neighbor lights, bad timing, weather, etc. that I gave up LRGB and RGB period. Sticking to narrowband from now. This is a cool video Luke. You always go in such interesting directions. Your content never disappoints. A lot of guys I know use hydrogen as luminance or a light pollution filter depending on the target. Synthetic luminance is cool. I like simplicity and broadband just doesn’t fit the bill.

[@lukomatico]

Hey Garnett! I hope you are doing really well my friend, it's great to hear from you! :-) I totally hear you man, LRGB/RGB are a real pain in the neck with light pollution the way it is these days, - it's a constant battle! - As you mention though, sticking to SHO is massively rewarding and no shortage of targets for most of the year! :-) I've considered trying using a "mild" LP filter to replace luminance, and since you mention it, that could well be the subject for a future video I guess! L vs LP-filter! Thank you again for watching, I really hope you enjoyed the video mate! Hope you have a superb weekend :-) Luke

[@cratervanawesome]

In my experience I've found LRGB is way better, because when you do LRGB you can shoot far less RGB as it'll just be used for coloring and not for details. I shoot <a href="#" class="seekto" data-time="241">4:1</a>:<a href="#" class="seekto" data-time="61">1:1</a> LRGB exposures. I know some people shoot far more Luminance than that ratio once they have enough for a clean stack of RGB, but i haven't done a ton of multi-night broadband. I started sort of backwards with narrowband mono so I'm just now revisiting LRGB as I start targeting LBN/Dark nebula targets.

[@sevenskiesastro]

Great video again luke. Interesting results. Does tend to show that the data counts tho would a full process give different results? Keep up the good work and clear skies bud.

[@lukomatico]

Hey Rob!! - definitely a great point mate, I agree it would be worth including a fully processed version in any future efforts 👍👍 It was awesome to meet you today by the way my friend, really a genuine pleasure!! :-D

[@consistent999]

Great video. You could also try creating a ‘Super Lum’ using the synthetic Lum plus the Lum. You can play around with the ratio but I tend to use 70% Lum and 10% of each colour channel as a staring point. Sometime is works and improves the SNR sometimes not. Keep up the great work.

[@lukomatico]

Great idea mate! It is something I'll definitely have a look at doing down the line, there are so many routes to successful imaging in this game! :-D Clear skies!

[@JoesAstrophoto]

Cool test Luke! If you know me, I love testing things out and have actually done this myself in the past (never made a video on it though). I've actually found that a great ratio seems to be 3 Lum subs for 1 of each RGB, for my sky anyway.

[@lukomatico]

Thank you so much Joe!!! - Yeah the good old pattern of LLLRGB is a superb method it seems! :-D I think I'll continue that kind of thing in the future!

[@avt_astro206]

Great Video Luke, I like The LRGB images, Cuz they really Bring out all The Details On Galaxies, I guess The Luminance Layer Is Meant for Bringing Out more Data, But in less Time!

[@lukomatico]

Thank you Avanteesh! Yeah man LRGB is a great tactic to tackle these lovely galaxies we can shoot, I can't wait to experiment more!! :-D Cheers for watching my friend!

[@actudoran]

Fantastic ideea and good job doing it! I'm pretty bent on using my scope with the Svbony 305 colour sensor for galaxy season going for lucky imaging! I will only employ uvir cur filter for now, might add IR pass and UHC for experimental purposes from Bortle 8 to 9. I suppose the rate of success depends also on target selection :) At first I thought your video would be about osc Vs lrgb mono imaging... :)

[@lukomatico]

Hey mate! - That should be a lot of fun during galaxy season for sure! :-) I think experimentation like you mention is the key to figuring it out from your location - there's so many variables! I reckon a OSC vs LRGB comparison could be cool! - Maybe I'll have to cover that one! Thank you for watching

[@SimonsAstro]

Very interesting comparison Luke, I agree the LRGB looks better! I love the way your backgrounds are So smooth! I can’t get mine as silky smooth as yours! Excellent the final image👍 Clear skies

[@lukomatico]

Hey Simon!! Once again an absolute pleasure to meet you today mate, I'm sorry about the late reply to this! The noise often turns out well aye, it's just the mottled backgrounds sometimes that bug me haha!! Hopefully APP will be helpful in getting things that next step smoother for you matey :-) Clear skies!

[@SimonsAstro]

@@lukomatico Thanks Luke, great to meet you too, the pleasure was mine! Yeah APP is the way forward, I’ll give the free trial a go👍 Cheers Luke!

[@peterturner1919]

Nice vid as usual, Rgb for me Luke, lot less hassle, time is my main problem, weather in Ireland rarely clear so when it is I make the best use of it keep em coming.

[@lukomatico]

Fair play to you Peter! - It's certainly a cracking option overall :-) I maybe ought to do a comparison between OSC RGB, and Mono LRGB/RGB - it could be interesting! Thanks for watching mate!

[@LogansAstro]

Very interesting video Luke. Agree that the LRGB was the winner there but interesting to see the use of a synthetic luminance instead came such a close second. I wonder if those blotchy background issues with the LRGB combination might me less of a problem with more integration time - next experiment maybe 😁

[@lukomatico]

Hey Logan! - Thanks so much for watching my friend, - I too was surprised to see sythetic Lum come so close to a true Lum, it wasn't what I was expecting! :-) Definitely worthy of further investigation, agreed mate! Clear skies and thanks again for watching! :-D

[@Astrobloke]

Hi Luke, great work mate. Its important to experiment with these things as everyones sky and light pollution is different and of course even variables like filter makes etc. If I go through the process of making a false Lum channel I use the image integration tool in Pixinsight adding the 3 channels, but in this hobby there are so many different ways to skin that cat as the saying goes. Clear skies

[@lukomatico]

Hey Glenn! - Thanks so much mate, it was a fun experiment to do because exactly as you say, you can't completely predict the outcome with this one due to the massive amount of variables! totally agree. RE: making the false lum, I should give that a go and compare to the method I tried, which was a manual combination of the masters in PixelMath - (using r*0.33+g*0.34+b*0.33) Thanks for the pointer! Just wanted to say mate what a blast it was to finally meet you in person, an absolute pleasure mate!! looking forwards to the next one :-D Clear skies!!

[@michaelharrington7797]

Great video I was wondering about this exact question and am only starting out so this has really helped. I think for the meantime I’ll stick with LRGB. But using the synthetic luminescence would be a plus if you don’t have much time on an object.

[@lukomatico]

So happy it was a useful video to you Michael, thanks for taking the time to comment mate! :-) definitely nothing wrong with sticking to LRGB! All the best, Luke

[@michaelharrington7797]

Would I be right in assuming from your Video thought that it’s not worth taking L if you have limited time and are willing to do a synthetic L through processing? The images of both L looked pretty similar to me couldn’t really pick the difference 🤔

[@lukomatico]

I think that would be fair to say Michael, yeah! :-) I'd definitely prioritise rgb before lum

[@ClausTuxen]

Got mine ZWO294mm with LRGB and NB filters on the way, going to be interesting time coming up.....

[@lukomatico]

Oh man yeah, I can't wait to hear how you get on with that setup, that'll be amazing!!! I remember you telling me you were switching, I just didn't realise it was so soon haha! :-D Good luck and clear skies my friend!

[@SonsofChivalry]

Interesting experiment, I had wondered about this too. One thought I had being in a similarly light polluted area, was to use an LP filter instead of a luminance filter. Possibly even use an LP filter in front of the RGB… 🤔

[@lukomatico]

Hey there my friend! - That's a great point, I've actually had the same sort of idea haha! I was going to run a test between taking pure Lum vs LP-filter as Lum, but not bother adding more suppression to the RGB overall - but that's an interesting idea in and of itself! :-) Thanks for watching!

[@gregorylatiak3333]

Good question -- depends on the target, but with my images, the LRGB filter set provide cleaner images, the RGB can be problematic due to colour crossover, particularly in the G (which has a red/IR absorption)

[@lukomatico]

Great point Gregory! - There's so many variables I guess between different types of filters, weighting of exposures etc - it's a great subject though IMO! :-) Thanks for watching!

[@ClearAmbientSkies]

The Sunflower looks great in LRGB. Disappointing however that the gradients are so defined in the LRGB image. Have you used Normalize Scale Gradient script for Pixinsight? There is much ado about it in the Pixinsight forums. With the recently release of PI 2.8.9 there is an updated normalize step in the stacking process which has been implemented, but I'm not convinced it is better than the NSG script (yet). The developer of the NSG script has done a spectacular job and it would be great to see how your LRGB image would do under its care. Clear skies Luke and thank you for another great video.

[@lukomatico]

Hey there mate! I've not actually tried NSG just yet, I use APP for stacking these days which does a similar operation though (when told to) - I will have to take a look into the NSG-WBPP update, if it's fairly automated then it could be quite impressive! Thank you so much for watching bud!

[@peterbriggs3408]

Try (R^3 + G^3 + B^3) ^ (1/3). Also try 2 or 4 instead of 3. Dunno how this will change things from your data.

[@lukomatico]

Hey Peter! - what are the chances, that's basically what I tried haha! great minds think alike I guess :-D Clear skies mate!

[@crm114.]

Excellent video as usual. I be very interested to see how LRGB stacks up against the equiv OSC camera for broadband target such as galaxies. How are you getting on with your EQ8R? I had a lot issues with mine (RA gear binding at low temp and excessive backlash) so returned in favour of an Ioptron CEM120.

[@lukomatico]

Hey Cliff! - Thank you so much my friend, I'm so happy to hear you liked the vid! RE: OSC vs Mono broadband comparison, I agree - that could be interesting indeed! :-) I may well have to try and cover that one!! On the note of my eq8 mate, it's been faultless! I'm really sorry to hear you've been having issues :-( we don't really get too extreme temperatures here so I guess that may be a factor overall though? Happy to hear you've got a mount you are pleased with now though mate, enjoy!! Clear skies :-)

[@iamjessieray]

Hm I know this is an older video but it's quite interesting. As someone who uses an OSC camera I never considered using any kind of lum but maybe I'll give a synthetic lum a try!

[@lukomatico]

Well worth a go mate! - The results can be interesting :-) Clear skies!

[@AstroLaVista]

Hey Luke, firstly have a great weekend at the Practical Astro show, I'm sure you'll have a great time and bump into plenty of people you know through your channel : ) I thought this was a valuable question to take a look at and the results were really interesting. Bit of a mixed bag when you consider the background gradient I thought but the signal was really nice on the LRGB and it was interesting that the artificial Lum RGB makes such a difference to the RGB considering it's the same data lol Was that yours or Chloe's dad in the background there! I thought he was running out to help you with that monster Newtonian of yours but saw he grabbed the cat :D Man that Sunflower at the end with the Monster Newt, YES SHOOT MORE!! :D Take care fella, have a gooden and thanks for sharing!

[@lukomatico]

Hey Chris! - Sorry about the late reply mate, I've had no reception all weekend and been catching up with sleep since we got back haha!! :-D The PAS was awesome, really enjoyed the heck out of it!! met a whole bunch of people and found the whole experience HUGELY positive!! loved it. RE the video comparison, it was pretty cool to see the results! - I too was surprised to see the artificial lum do such a good job! It was my dad by the way haha, she's suppoed to be a house cat but loves to try and go for a walk around the garden haha :-) Glad you liked the final image by the way mate!! :-D As always, a pleasure my friend! - Clear skies!

[@AstroLaVista]

@@lukomatico Hey dude , that's brilliant! I'm glad you had such good time, and I'm sure we'll meet at an Astro event at some point which would be cool : ) Have a good week fella!

[@lukomatico]

That would be awesome mate, 100% we'll have to do that! I hope you have a super week too, all the best! 🙏

[@MazzifLOL]

Cool video. Do you have a cover plate on the back of your 300P-DS? I tried to make one for my 200...turned out good, just a little off in diameter (maybe 1mm or so), so while it looks cool...doesnt block all the light (yet). ~Clear Skies.

[@lukomatico]

Hey there mate! - I do have one yeah, I made it out of some foam tile - worked well, seems to be no leaks! :-) Thanks for asking and hope you are having some clear skies mate!

[@davidleejenkins]

Nice video Luke! Now the question is, how much Luminance is ideal to capture? In other words, what ratio of L to RGB produces the best results.

[@AstroB7]

The more Luminance time, the better. The best thing to do is to have the maximum integration time you can on the Lum. That’s where you will gain details ;)

[@lukomatico]

Hey David! - It's an interesting question! I think getting as much lum as possible is always a good thing, as long as you are still capturing enough RGB overall to have good colour after some heavy stretching - but just how much RGB is a new question in itself! :-) Thanks for watching mate!

[@JethroXP]

Have you considered installing a permanent pier? Watching the telescope gymnastics to mount that large scope with the camera attached just made me cringe, thinking "please don't drop it!"

[@lukomatico]

Hey Jason! Man oh man, I would LOVE a pier (well, an observatory really!!) - It worries me too, the thought of a slip or trip is a constant concern! I'll give it some serious thought I guess! Thanks for watching my friend :-)

[@JethroXP]

@@lukomatico Here is a look at my setup. It is truly a game changer having a setup that is always ready to go. You can do things like take advantage of even just a couple hours break in the clouds without all the hassle of setup and tear down, and you can get very consistent in your sessions that span multiple nights. kzbin.info/www/bejne/immnhHpnpq-sorM

[@lukomatico]

Looks awesome mate, enjoyed the video!! :-D

[@bucolic9343]

how does the RGB fit with L? Does L work just like an amplifier to RGB? For instance if we have R: 0.2 G: 0.2 B: 0.1, and L: 0.5 at some pixel, then the resulting LRGB will be L\L' (0.2, 0.2, 0.1), where L' is the lum of RGB as implied by L' = 0.2126 * R + 0.7152 * G + 0.0722 * B. Am I correct?

[@larryfine4719]

Pardon my ignorance but why not do just a luminance layer - I can't see the value add for RGB here (I'm watching this in HD and can't see the color!). And if you go luminance only why not just use a HA filter? I did see some color in the final processed image but couldn't you just turn the hue to purple?

[@lukomatico]

I hear ya mate, things don't come across too well on the video - I'll have to redo this experiment and try again sometime! :-) Cheers!

[@paulwilson8367]

How about LRGB or RGB vs OSC? I have special problems, since I'm shooting at F2 and lack the ability to employ a filter wheel. My camera must be removed for each filter change, so if I do RGB (I have left out the L though I do have the filters (Optolong), I have to do an entire night session with just one filter. You would think this would really add great signal, but I haven't had great results. In Bortle 7 with RASA 8, my RGB just will not color calibrate correctly, though I try and try. The stars get pink, or too blue. I tried linear fit to balance the channels and that helped but didn't cure. As an experiment, I shot M81/82 from the dark site (Bortle 2) using OSC, vs three long nights in town at Bortle 7 RGB. The dark site data blew away the RGB max effort, not even close. 6 hours in the dark trumped over 15 hours in bortle 7. Perhaps I will try LRGB, perhaps with just a couple of hours of L? After 2 years avidly shooting everything that comes over my house, I am deciding that galaxies from town are very so so, even with no moon and LP filters when using OSC. I did ok with only the biggest and the brightest using OSC, and poorly with everything using RGB on galaxies. One execption, my only RGB "success" was the bright M33, with my old ASI1600MM. With my bigger, heavier ASI2600MM, I have had poor results.

[@lukomatico]

Hey there Paul! - Man I'm sorry about the late reply to this! It sounds like you've had a real handful to contend with there, I can only commend your patience with the matter! I think OSC will actually put up a real good fight vs LRGB, at least that's what I expect to see - I'd hope this is something I can create a reasonable experiment for :-) Thank you very much for the great suggestion! All the best and I'm wishing you good luck with the challenges of galaxy season my friend!

[@charlesowillford2474]

I missed what the exposure times were for each grouping. Or how many exposures in each grouping. I think that would affect the SNR? NO?

[@lukomatico]

Hey Charles! All exposures were 60s long, bin 2x2, - I have strong light pollution here so 60s is plenty for any channel aside from narrowband in terms of swamping shot noise :-)

[@charlesowillford2474]

@@lukomatico Why did you bin? I just realized that we don't know what your imaging train was? Thanks for responding!

[@lukomatico]

Hey Charles! - I was actually doubling up on experiments haha!! - I took some (very few overall) frames at bin1 and some at bin2, I'd hoped to see the effect of image scale/sampling ratio clearly illustrated but it'll need a better comparison all of it's own I think 👍 But anyway, the reason for keeping shooting bin2 on the night was none other than just curiousity! As to image train, 300pds, aplanatic coma corrector, zwo lrgb filters, 1600mm pro 👌 Cheers mate!

[@Steve_The_Ignorant_Astronomer]

Luke , to me they all look real close. Since it is so so hard to get nice skys I think RGB one shot is the way to go. It would take so long to get all the filters in,,,, Now what is synthetic Luminance ? And how do you make one ? I use the 294MC pro, and use a sky filter and a Optolong L-pro

[@lukomatico]

Hey Steve! - Man do I ever hear you with the argument for one-shot colour!! so much more simple to use overall, and still great results! :-D RE: synthetic luminance, in this case I took the R G B channels and added them together in PixelMath (in PixInsight) - with roughly equal weighting, so r*0.33+g*0.34+b*0.33 - the result was pretty smooth compared to any of the source files, a good improvement! :-) With a OSC cam however you can simply extract the luminance from the image and use that instead, again in PixInsight - it's just one buttonpress! amazing :-) Thanks for watching matey and good luck with that 294!! Enjoy!

[@Steve_The_Ignorant_Astronomer]

@@lukomatico also how the heck do you figure out pixel math formulas ?

[@Steve_The_Ignorant_Astronomer]

Hey Luke , How do you do a synthetic Lum... I use color cam , is it hard to do ??

[@lukomatico]

Hey mate! You can click the 'extract cie/l' button on the top left menu bar on pixinsight to drag the luminance channel out of your osc image 👍 hope that helps!

[@Steve_The_Ignorant_Astronomer]

@@lukomatico Will try when i get some more data. I think I lost my icons I setup. So upset... Hope I have them on a backup drive , UG

[@frankm81m82]

Let’s say you did 1hr luminance and 20 min each of RGB, I think to get the equivalent RGB only in terms of signal, My guess you would need 1 hour and 20 minutes for each RGB filter. Since the 1 hour Luminance collects light from all 3 colors at once. Luminance filter has a times saving benefit, but like you said the Light pollution Gradients are worse.

[@lukomatico]

Hey Frank! - I think you're probably right on the money there mate, I guess it would probably take nearly double the total integration to make pure RGB match LRGB of half the total exposure, from an SNR standpoint. - Maybe worth a test in the future! Clear skies :-)

[@stxe34]

mono camera sensor will be a lot more sensitive than an rgb sensor.

[@lukomatico]

Hey Stef, this video was about comparing LRGB vs RGB imaging, both with a mono camera :-) not about OSC vs Mono

[@beatsntoons]

Ha, this is the rabbit hole question mate. RGB could possibly pull ahead when you have lots of time and data to play with. For most people who don’t have that, LRGB should be fine, but boy you could go into this subject for years and not come out sane. Quick question… how do you find the EQ8 pier? I might get one for my EQ6R. Is it sturdier than the EQ6R tripod?

[@lukomatico]

Hey mate! haha, agreed - it's a real rabbit-hole for sure! RE: eq8 pier, it is RIDICULOUSLY sturdy, as in you could stack hundreds of kilograms on the thing - it's so over-engineered (and thus, bloomin' heavy) but that's how they chose to make it! :-) I'm not sure about it's compatibility with the eq6 though, the mating plate of the eq6 is a lot smaller than the one from the eq8 so I reckon it would probably need a lot of modification to be workable? - could be interesting though! Thanks so much for watching mate!