I'm a stickler for flats. A couple recommendations: (1) Before integrating your master flat, calibrate your flats first with a master bias. (Alternatively you could use master darkflat, but a master bias is easier, more reusable, and arguable just a better option.) This can have a somewhat significant noise reduction in the final product. (2) Then when it comes to integrating the calibrated flats to make a master flat, uncheck the "Signal and Noise Evaluation" checkbox at the bottom, in addition to the settings Dylan shows in the video. (Leave this checked when integrating lights, but uncheck it when integrating flats.)
@briantheprimateastro4 ай бұрын
I like the tribute Alyn Wallace.
@DylanODonnell4 ай бұрын
Thanks Brian
@noirforamen4 ай бұрын
Wait I'm confused, what happened?! I don't have ANY info
@Snow.20404 ай бұрын
@@noirforamenAlyn Wallace unfortunately passed away a week ago from an infection after a nasal surgery.
@noirforamen4 ай бұрын
@@Snow.2040 no wayy...he was such a great guy...
@alineradventureswithsimons794 ай бұрын
I noticed you didn't say Everything is meaningless and we're all going to die which I usually chuckle at. Then I saw and appreciated the tribute to Alyn. The loss of Alyn Wallace has touched us all so deeply. Ride those stars Alyn!
@mtnhorn26194 ай бұрын
Thank you for the very kind, tasteful tribute to Alyn. I greatly enjoyed his art. He shall be missed.
@geert58114 ай бұрын
Not the usual closing sentence but a tribute to a guy that gave us every month a nice overview of what is in the sky the next month, touching ... g.
@MrGp3po2 ай бұрын
On occasion, we all suddenly discover something new and wonder why that useful tidbit eluded us for so long. I started doing Flats with a DSLR and t-shirt, then switched to using an $18 tracing pad for convenience. (Temperature matching Flats with Darks/Lights isn’t necessary.) I routinely puff off dust on the objective before each session and find the Flats work well for several sessions (assuming the image train isn’t altered.) That’s just laziness on my part since Flats are so fast and easy. Great video. Love the tribute to Alyn. He was a gem and I thoroughly enjoyed his videos, especially when he shared adventures in the field. He is missed.
@0815mkl4 ай бұрын
As others have recommended - calibrate the flats with some dark flats (same seetings, but without light) or at least bias frames, when you are using also dark frames for calibration. otherwise you substract the read noise twice. one time with the flats and one time with the darks, Taking the flat frames before the imaging sessions is tricky as the focus is important. The dust spots will change if you change the focus, so you need to take the flats with the same focus setting as your lights. For OSC (without or with only one filter) I take the flats in the morning after the session towards the bright sky with a white T-Shirt in front of the lens. If I use different filters troughout the night (that would apply also for different filters with a mono camera), I take the flats after each filter run. I have used my iPad for that, but if the exposure time is too short, it has some banding due to the flickering of the panel. I switched to a lightpanel instead, that works much easier.
@frankm81m824 ай бұрын
You need flat dark or bias frames to remove the offset pedestal irregardless of how noisy the camera is. Since the lights have the pedestal, and the bias or flat dark has the pedestal, subtracting removes it and makes the math work out correctly
@cliffwatson84784 ай бұрын
OH SHIT! I didn't know about Alyn, He was great, thanks for the tribute may he rest in peace.
@EH-pm1ke4 ай бұрын
This is my favorite channel, make more videos, everyone else is boring
@DylanODonnell4 ай бұрын
Ahh thanks man :)
@BadYossa4 ай бұрын
I always enjoy your no bs approach to this hobby. It's very refreshing. It was to good mention Alyn Wallace. He's a great loss to our community.
@DylanODonnell4 ай бұрын
Cheers man
@noddyonice4 ай бұрын
Simple, moving tribute to Alyn. 👍🏻 Noddy
@lewleo9994 ай бұрын
Get ready for even more gradients if couple of bucks spent on a LED panel is to fancy for your flats ;) Sky and walls tend to be unevenly lit like there was a single source of light. Imagine that.
@DylanODonnell4 ай бұрын
Depends on your walls :) finding a blank, evenly lit surface isn’t too hard though!
@astromatt754 ай бұрын
I started out using the sky or walls for flats and had exactly this issue. I ended up buying a £20 LED panel (nothing fancy) from Amazon and have never looked back. It gives even light and full control over the brightness. Using a panel with brightness control is most useful when NINA cannot work out the correct exposure due to too much light coming into the scope - usually happens when I am using a broadband filter or filterless. Without the panel, it would be a lot of effort trying to get the right lighting conditions be it walls in the house or sky.
@lewleo9994 ай бұрын
@@DylanODonnell Sure, it all depends on your situation. I've done the sky flats n t-shirt, I've done walls, I've used to do laptop monitor flats. Light panel + NINA flats are the most consistent and fastest for me.
@dumpydalekobservatory4 ай бұрын
I never did flat frames for years & when I tried they never worked anyway until I found NINA, I do use an LED panel with a T shirt over the RASA & NINA does the rest it's awesome although I've never bothered using darks so got lazy there. Loved the tribute to Alyn Wallace at the end to such a shock to the community when I heard the news.
@marshawilcox4 ай бұрын
Brilliant, as always, Dylan. I appreciated your step-by-step explanation through the process. IMHO, it's important to understand that before going to something like WBPP (which, lazy me, I use now). Your tribute to Alyn Wallace was touching. Thank you for remembering him.
@psiddarth35814 ай бұрын
I really dont understand why you just have 47k subs. Definitely underrated.
@southbronxny57274 ай бұрын
I think he needs to change his channel name to something with 'astro' in it to get more subs.
@DylanODonnell3 ай бұрын
Thanks man. It’s because of my personality, a lot of people dislike it :)
@cucubits2 ай бұрын
@@DylanODonnell nah, it's the loud obnoxious intro :)) ...and the visual astronomers telling their astrophotographer friends to not subscribe
@ianspector13574 ай бұрын
It may be worth mentioning that you can also pile all your light, flat, bias and dark frames in a single folder, tell Pixinsight to 'add files' in Weighted Batch Pre Processing and press go. Iy will sort out which is which, create your master dark, flat, bias and apply all the most appropriate settings. Seems easier than your manual manipulation of the flux capacitor.
@DylanODonnell4 ай бұрын
I know. But I’d rather break the processes down into their discrete blocks so people can learn and understand each one. I never batch because every target is different and I treat each dataset slightly differently.
@ianspector13574 ай бұрын
I know that you know. I hear so many people say how hard Pixinsight is to use but the Pixinsight defaults are really excellent. I simply wondered if the manual approach would have potential users running home to Microsoft Paint (or whatever the second best processing software is).
@DylanODonnell4 ай бұрын
good point. As a beginner I always found manual easier because then it’s easier to know what step I messed up 😆
@beyondvger36824 ай бұрын
@@DylanODonnellAin't that the truth 🤣
@bronco_fv4 ай бұрын
Although the manual make it easier to see what you messed up, it’s also easier to mess up. Having said that, WBPP give the same possibilities to adjust the parameters, it is running the same processes.
@hernanlucasgilperuzzotti32774 ай бұрын
Perfect flats!!! White T shirt and the sky !! Add a elastic to prevent wrinkles on the fabric!!
@DylanODonnell4 ай бұрын
👌🏼
@Astrogator14 ай бұрын
Not had any notifications for new videos for months (thanks KZfaq) great video flats have always been a pain, so generally haven’t bothered, going to try again.
@DylanODonnell4 ай бұрын
I feel / felt the same way! I think many people do. I hope you didn’t miss too many of my vids :)
@petesastrophotography4 ай бұрын
Excellent video Dylan. Sometimes the simplest solutions are the best. I have deep sky dad flat panels for my dual apo rig, these work very well. However, I have recently purchased a 12" RC and have been wondering about taking flats. After watching this I remembered that I have some fairly large flat white upvc panels left over from remodeling my bathroom, one of these attached to the obsy wall would be perfect for this so no need to buy anything👍
@masonk23864 ай бұрын
You always seem to make just the video I need right when I need it!
@iamjessieray4 ай бұрын
Once I started using NINA's flat wizard, taking flats was such a no-brainer that I don't have an excuse to not do it. I do use a light panel with a couple of pieces of paper between the telescope and the panel to both dim it and to disperse the light a bit more and that works great. I will never not take flats again.
@DylanODonnell4 ай бұрын
It’s so good !
@Rtd_astro4 ай бұрын
Nice work Dylan!! Alyn will be missed 😢
@southbronxny57274 ай бұрын
The only thing that help me best were taking sky diffused flats with dyi cover during the imaging session. Basically put a diffused sheet cover over the objective at the beginning, middle and end of the session to cover the entire light pollution dome. Don't change any camera settings and take ten each. No need for any other calibration frames or gradient apps. Daystar sells diffused glass covers for solar imaging that can be used for night imaging too but are expensive. So sad about Wallace.....Rest In Peace Kool Guy.
@JoeBob795694 ай бұрын
I recently upgraded from the ASI585 to the SV405cc (with the IMX294 sensor) so I had to actually learn how to do my flats and darkflats properly. During the day my rig sits behind me so I can just point the scope at my PC screen with an empty Notepad open, and shoot away, but I do have to throw something over the screen, or the scope, otherwise NINA makes my exposures too short, and the SV405 doesn't play well with flats below about 2 seconds. Which is also why I have to use darkflats instead of those really short bias frames. But yea, the Flat Wizard in Nina is great.
@caviestcaveman86914 ай бұрын
dang never woulda thought you of all ppl didnt use many flats thats so neat and odd lmao gotta love the hobby so many ways to do thigns
@CAPAstro4 ай бұрын
Even easier would be to use NINA's Twilight Sky flats exposure instruction. I do it at sunset and completes in about 4 mins for a set of 7 filters (30 flats/filter)
@artyombeilis90754 ай бұрын
I just use my tablet screen as flat panel. It is feature that is built into my live stacking app - so camera connected to android tablet for EAA and when I just use same tablet screen to create flat surface - so I can do it at night on demand. The app has built in feature to make white screen during flats collection so it makes it super easy (at least as long as the tablet larger than the scope aperture. Though it works well for EAA and works at night
@TheHoaxHotel4 ай бұрын
The number of rubber bands that I've flung off the roof while trying to put a tshirt over the scope is... around 3
@justintowne14 ай бұрын
I was honestly expecting a sarcastic Taylor Swift reference when you said blank space…. 😂
@brandonrunyon4 ай бұрын
Some cameras are more difficult to capture good flats. The asi294 (both color and mono) require longer exposure flats due to noise of low exposure times. So if you have to do a 3 second flat, your light source needs to be super dim, but not too super dim... that requires a good source you have a lot of control over.
@TexasEngineerScotty4 ай бұрын
Dylan, thanks for the info. I initially shot all of my flats at the sky with a T-shirt but eventually I started having that nagging OCD voice telling me "how can they be uniform, what if the color of the sky is off today". These were things I could logically explain away to myself, but I eventually found myself giving into voices. I think folks should know even if you have a larger SCT (i use an Edge HD 11") you can buy an LED tracing panel for less than $20 American that will fit your scope. Not only that NINA Flatwizard even has a "point to zenith" button (just make sure you have tracking turned off!). My big question is this "do you actually use that workflow for calibrating? Or do you let WBPP handle it and you are showing us basically what WBPP does effectively? BTW as a Plano, TX guy I appreciate your support of one of my favorite locals ( guitar and T-shirt!)
@DylanODonnell4 ай бұрын
Love polyphia! Got to meet Tim recently :) yes I’m sure one day I’ll give into temptation but the day flats are just so easy. I don’t even have to walk outside to setup. I don’t use batch processing because I like to monitor each step but I also process filter runs while the scope is still going over several weeks, rather than wait for one big data process :)
@larryfine47194 ай бұрын
You can be even lazier than the flow you use. Just point PixInsight's WBPP at the flats/flat darks and it works it all out.
@DylanODonnell4 ай бұрын
I’m anal like that.
@ronm65854 ай бұрын
Thank you.
@seafurymike4 ай бұрын
26000 ADU is my target for flats. set in the histogram mean target section. Flats of course dont need to be cooled as you indicated, just the long exposure darks.
@DylanODonnell4 ай бұрын
Yeh I misspoke there! There isn’t even an option to set temperature in the flat wizard.
@lawrenceklein37094 ай бұрын
Order up and send one of those Science Toys over this way, please. I can't find the proper link. 😉 Great tribute to Alyn Wallace.
@blobrana85154 ай бұрын
Flats are so easy to do it should be part of every photograph session. You can even cheat, if using the same telescope setup, and use a previously made flat frame (but new dust motes will not be removed).
@natejackman61614 ай бұрын
I have to comment on the light panel. Especially if anyone travels to a dark site: get the light panel. They are cheap, consistent and can be powered by your ASI Air if you use one. I think the one for my C8 was $15. Here is my real comment: If you are going to the trouble to stay up late, travel to dark skies, spend the money on a good camera, you might as well commit to taking the light frames. Just like the video showed, they are easy to do.
@DylanODonnell4 ай бұрын
True :) I do note the exception for fieldwork … but also like… there’s the sky. And one less thing to take!
The more light pollution you get, the less you can get away without flats. The dust motes visible in your flats would wreck my images if I didn't use flats. In fact, if a flat comes out wrong and I notice too late (ie: after the rig was disassembled) then I'm screwed, I have to mostly drop that data. From Bortle 9 the overall brightness of the image makes the artifacts those dust motes create leak all over and mess with gradient reduction and everything else down the pipeline. I've tried sky flats, and they are tricky to get right, especially if doing narrowband where exposures get long and makes the whole process tkae quite a few minutes. Sky brightness changes very fast around dusk and dawn, and with long flat exposures by the time you got your 20 flats the sky may be twice as bright or more, meaning your flats are always either over or under exposed. Long story long, a flat panel is quite handy, and it doesn't need to be an expensive EL panel. I use a dirt cheap LED tracing board, and it does the trick just fine.
@DylanODonnell4 ай бұрын
Yep, I do note the field situation is the exception but if you’re just pulling your rig inside any blank surface would be ok. Ambient daylight seems to work best for me at any time of day.
@S12Astro4 ай бұрын
Nice tribute to Alyn Wallace at the end. What a tragic loss.
@stevenholt8244 ай бұрын
Needing over 3s flats exposure for my 294mc pro( to ensure a linear response ) makes flats difficult , I haven't found anything that can dim the panel sufficiently without the light becoming uneven . Rest In Space Alyn .
@johnknight72934 ай бұрын
Crikey, no wonder you didn't bother before - so many manual operations, what a nightmare! My situation isn't really comparable (one-shot colour, different kit & subjects) but Siril scripting seems so much simpler.
@cliffwatson84784 ай бұрын
Why the face fungus, Too many late night's? I went to Texas for the eclipse! And what a Fantastic eclipse! Oh what a trip! Oh and I stayed with my mate Tom Pickett (Pickett's Balls, I sent you a photo of it.)
@elithic4 ай бұрын
Luv ya', Dylan. But I'd never do flats this way. A good flat panel (e.g., Spike-A, Optec, or PrimaLuce) with USB-controllable intensity in order to shoot flats for all 7 filters at the same, fixed duration (usu. 4s for me), and a set of flat darks is the only thing that has ever worked for me. The quality of my data jumped significantly when I figured all this out. It only took me five years.
@DylanODonnell4 ай бұрын
I can do all my filters at the same time and they work great :) no extra gear (or even movement of the rig) required.
@ConnorRoss4 ай бұрын
I also use a wall haha, but I move the telescope because the vignetting remains persistent but any dark patches on the wall are smeared out
@jon38904 ай бұрын
10 min exposures for the final pic, wow!
@DylanODonnell4 ай бұрын
Yeh it’s so much better than my last attempt at the same patch of sky! Lots of dust.
@jon38904 ай бұрын
Seems mental. You've got a great rig and sexy guiding graphs.
@ApoorvaIyer4 ай бұрын
I have noticed this theme in all your videos. But why don’t you use WBPP?
@DylanODonnell4 ай бұрын
My images take weeks sometimes so I usually process one filter at a time while the scopes still going on another one :)
@geoffhealey8664 ай бұрын
Hi Dylan, I am curious why the gain needs to be the same as your lights. If you are looking for the desired illumination level as configured in the imaging software I think the only influence gain has is determining the exposure length to get that level. From my experience lowering the gain makes it easier to get reasonable exposure lengths if the light level are high but gives the same calibration outcomes.
@DylanODonnell4 ай бұрын
No idea .. you could be right but the flat wizard doesn’t seem to have an option to change it .. just locks it to whatever the camera is currently set to. I haven’t checked the meta data tho.. maybe it’s changing ? 🤷🏽♂️
@geoffhealey8664 ай бұрын
@@DylanODonnell Hi Dylan, thanks for your reply. Might be a NINA thing, Voyager allows for gain/offset changes for flats. Warm regards Geoff
@LogansAstro4 ай бұрын
I laughed when I saw you having a sneaky game of Fortnite - I've been playing it with my sons. It's fun!
@DylanODonnell4 ай бұрын
It is!
@Desertskyobservatoy19254 ай бұрын
I'm lousy at taking flats and I use a light panel with an assortment of gels to dim down the brightness. I'm wondering if N.I.N.A can be used in conjunction with the light panel to help me take better flats?
@DylanODonnell4 ай бұрын
Yes!
@Lasserubinskov4 ай бұрын
"Flat Frames are easy" *Clicks several strange ImageIntegration settings* I kid. Flat Wizard is great :)
@DylanODonnell4 ай бұрын
Hehehe
@cjmenagh8824 ай бұрын
If you truly want to be lazy with a Sony 571 you really don’t need darks. Flats though, yeah, ya need those.
@matthewbaker75134 ай бұрын
Me slowly making a big dob workshop "Yes, this costs more, this must be better" :^)
@mrgrimm23194 ай бұрын
Why not just use WBPP. It will create your master flats and master darks for you, then calibrate your images with them. Much easier in my opinion.
@spookysandwich13554 ай бұрын
so if you point at the sky for flats wont clouds crossing your lens view be a problem ? up till now i just hold a piece of white A4 paper over the lens while facing up
@DylanODonnell4 ай бұрын
That’s a great trick. Even and blank. No powered light required, just ambient light is fine as long as it’s even. You’re focussed way out anyway so even slightly imperfect surfaces blur and average out.
@DylanODonnell4 ай бұрын
And yeh clouds would be too dynamic , changing and uneven. Unless it’s very overcast I guess.
@spookysandwich13554 ай бұрын
@@DylanODonnell many thanks for the reply Dylan , here in the UK cloud is one thing we are never short of or rain England is well known for it haha but will try an overcast day with minimal cloud structure as possible and give it a shot but yeh the paper trick does do a job :) always been a huge huge fan of your work mate
@cliffwatson84784 ай бұрын
So this has to be done every time or just once?
@DylanODonnell3 ай бұрын
Every time you change the camera or rotation. Because then all the dust motes change !
@MrPaulpilcher4 ай бұрын
Another great Video mate. Classy Tribute to Alyn🥲
@DylanODonnell4 ай бұрын
Thank you Mr Paul!
@HighBoss4 ай бұрын
Wait so I can just take flats from the inside of the dome? I thought you need a flat, evenly illuminated surface?
@DylanODonnell3 ай бұрын
Yeh apparently it’s flat and evenly lit enough! Works perfectly.
@Mike3217954 ай бұрын
So this whole time you were not using flats?
@DylanODonnell4 ай бұрын
Pretty much !
@WilliamBlakers4 ай бұрын
With this dust i do thee mote you.
@bobbymckenzie32022 ай бұрын
Flats have vastly improved my images.....they were dog shit before 😂
@DylanODonnell2 ай бұрын
right??
@keithhanssen74134 ай бұрын
I wouldn’t say taking flats is easy.
@elbass04 ай бұрын
LOL! a quick ALT-TAB. Nothing to see here!
@joseribeiro95644 ай бұрын
Life is meaningless indeed..
@cuisleproperties63513 ай бұрын
Look after your mental health.
@richhudnut51104 ай бұрын
This is where AI could really help, "hay G, image M16 / does everything" more time for other hobbies...