TiffsAndAstro

the lower your bortle, the better it is to do longer exposures it seems. or at least lower bortle gets the most out of longer exposures?

****after watching this excellent video*** this is such a good video in so many ways (but also horrible in its implications) i can see why you linked it. no pressure or expectations on answering any/all the stuff i ask below. it would be asking a lot of anyone apart from maybe the guy in the video what temperature do you cool your 533 sensor to? because for me with bortle6 and f5.8 scope i should be able to set the imx533 to just say +2 (or even higher) centergrade and avoid ar glass window frosting if the svbony doesn't have a ar glass window heater (which is doubt it does) and swamp the read noise with just the light pollution? then i can have a single library of darks as its unlikely to be more than 32 centegrade at night in the nw uk there is talk of future sensors being able to read whatever pixels you want whenever you want. there needs to be software that can recognise (for example) the pixels of a galactic core and read them out more often then those pixels in the wisps around the edge and can get best shot noise per pixel no matter if imaging a bright or much less bright area of a target? also the sensor's outer pixels could be used for guiding? is there an equivalent or another name for "PSF signal weight" when stacking in siril because its options don't inlcude that phrase. maybe "wighted fwhm" or "noise"? also thinking about dual narrowband and osc, i think (im definately not sure as i doubt i've compared enough good images to really get a good understanding of what i personally like) i prefer broadband 'colour' over what appears to me to be a narrow range of reds for Ha and even smaller range of greenyblues for O and nit much else?. i don't mean stars i mean in nebulosity. its why i've asked here in the past if the colour in my one and a half 'decent' images is really just stretched noise resulting in colour. if its not, and its 'real' colour from the target, why don't other people seem to like it as i do? how is he measuring his diminishing returns in snr/number of subs as he continues to gather more data? is there a way in Nina? not sure how this can be used for the broadband ill be doing, even if/when i get dnb filter. not sure if lrgb directly equals osc. but then im not even sure i can combine osc with Ha + Oiii into one final result. how many exposures are required for ground based images to rival the snr of hubble and reveal feinter detail? its interesting that both lucamatico and cuiv both seemed to conclude that sub times don't really matter, but because their tests are in bortle 6/7 and bortle9 their tests wouldn't show much difference, but there would be in lower bortle areas. this is such a good video. apologies in advance, but as you have a 533 colour sensor, soon after mine arrives (if i do get it) i'll be asking you what gain (101?) what offset (+70?) and stuff like that. sorry so to sum up what is my ideal exposure length? (lol sorry couldn't resist) seems longer exposures won't hurt snr, but have disadvantages for planes, wind, blips in guiding. im not sure if there can ever be a correct answer for this question as only so many of the factors that influence it can be knowns. if i live near an airport, the likely hood of planes is higher which would suggest shorter exposures. but not too short did the video guy turn this into an online tool to so others can more calculate all this? its really weird that i thought i got better results with my dslr at iso 200 (accidentally) than the recommended 800 but set it back to 800 because that had the best noise response. i was doing 180 sec subs. a while back. i think i'd have to do as guy says lower than unity gain balanced against the amount of bright/darker of the areas of my target and balance that with my gears ability to do longer exposures and aircraft frequency? i like how the two 'presenters' towards the end clearly didn't understand the point the main guy was making lol

still watching video it will take a while. i did see a cuiv video using sharp cap info via nina to determine optimum exposure lengths and they came out at like 7 seconds or something silly. something about the only thing that really matters is swamping read noise. but im hoping your video explains this and related stuff really works and it looks like it will. many bullet points during intro main thing i can't get my head around though is if wanted signal is directly proportional to exposure time, how would a longer exposure help as long as its long enough to make the wanted signal greater than signal that is not directly proportional to exposure time. i doubt im explaining that too well, sorry. back in at least 1hr 30mins i lied. a better way to explain my question might be. even in bortal 9, the photons per sec from light pollution cannot be greater than the photons per second from a target source, else the target source could never be imaged. this i guess isn't true for the specific wavelengths used in narrow band (as light pollution is not strong in those wavelengths), but might be in broadband?

Can I ask say why one 5 mins sub is better than five 1 min subs? This seems to be quite a topic on YouTube. I would imagine longer means feinter details captured, but if stacking multiple images this might not be the case? Maybe if stacking was additive, but that would just result in blown out stacking results?

This setup should let you image process for ten years touch wood. Plenty storage is definitely useful.

For some context in case it helps, I'm using an 8 year old gaming pc to do my processing and a 9 year old MacBook pro to control my imaging sessions. Both work fine for their new uses and a newer desktop will make processing faster but for stacking etc I can go do something while I wait. Certainly fast enough for me for maybe 2 images a month cos clouds.

Nah I'm going for the tec cooled one. Seems a relative bargain if there is such a thing. Will probably have to sort a rotator separately but like you said with a square sensor its less of an immediate issue. Getting the filter drawer and UV/ir cut filter with it. https://www.svbony.com/sv605cc-camera/#F9198K-F9127A-W9184A

i think i'll skip svbony's solitary rotator offer as i think its for a specific telescope. m68 is pretty rare. does anyone know if i get a astro essentials one from flo it should still work with my gear and allow me to get back focus? seems a decent range of spacers included with the svbony? ill email them and ask i guess. also a rotator doesn't seem as vital for a square sensor. https://www.svbony.com/sv605cc-camera/#F9198K-F9127A-W9184A is there anything obvious i might have missed to check on? other adapters or anything? another slight update, svbony been replying to a few questions to me this morning and im now very impressed with their answers and speed of response. they also told me not to buy today and wait until tomorrow when the price will drop further im going to have to bite the bullet and see what happens, i think

So good you bought it twice? (Sort of). So far I haven't seen any bad comments and yours have just confirmed for me I should go for it over a 585 even with the added cost. I had a really clear and great reply from Nina at svbony clearing almost everything up. I just hope the svbony version compares reasonably well to the competitions version. Only one way to find out. I'll let forum know how I get on

not keen on eletrickery i guess ill see how i current one gets on powering both items if i can find a suitable t junction etc. and some cardboard i might even stretch it to premium cardboard.

cool ty ill look around for a t junction and stuff. would mean almost one less wire

i like it. its better than i've managed. i think this might be a tricky target for those new to the hobby like me, so really well done.

Vroobel has been extremely kind in letting me have some incredibly nice data to practice processing with. Just thought i'd post this here for reaction, etc, with Vroobel's permission. id call this a first pass to see what potential is there. Compared to Vroobel's own version on astrobin i think my processing of it is very much lacking. just to be very clear, this is Vroobel's data (darks lights bias and flats) and just my stacking , processing and developing in Siril, graxpert, and a little gimp. Not even astrosharp yet.

Is there a power extension lead I could attach to my mount power supply so it could still power my mount and then run up to sv605cc? Ideally via a second extension to that lead so I detach it from stuff more easily? Would it be able to supply enough juice to both? https://www.firstlightoptics.com/batteries-powerpacks/lynx-astro-12v-dc-5amp-low-noise-mains-power-supply.html Some sort of t junction, then then one more shortish extension lead? If not, I guess I could try the mount on rechargeable batteries

apologies for 4 pages on "i need help buying a cheap astro cam" i wasn't expecting to need this much help and advice on what i thought would be a relatively straightforward thing. sv605cc uses the imx533 sensor and includes what im guessing is all the bits i need from the flattener back, to get back focus. https://www.svbony.com/sv605cc-camera/#F9198K doesnt seem to include a power supply, of course it doesnt.

your results prove how good it is, but i have the filter issue and rotation issue to also deal with and a modded dslr won't help me with that

im looking a the site atm, and £95 is a good deal, but it doesn't help with my rotation or uv/ir cut or nb filter swapping i'd rather keep the £100+ (postage there/back) and put it towards a proper astro camera, rotator and filter drawer.

Sv605cc is £530 on their website. That's a boatload less than zwo version. Might be doable maybe a get a rotator that doesn't use m68 elsewhere. This is a multiple pita

Hope so but no way of knowing. I think going forward I need to be able to go at 30minutes notice.

Nah it felt a bit dubious using the nose piece held in by two screws no compression ring. I did have a go loosening/turning the focus tube adapter and flattener about 3/4 of a rotation but then optical train felt floppy and probably puts stress on the threads

I think so far in the last month I've taken 15 minutes of usable subs. Thank god I have cheap light easily quickly grabable gear ;(

I tried using it on the moon even mono it looked pretty nice. I really do believe you about time on target but as I've already rotated my camera it will be hard to add to my few existing projects. Pinwheel galaxy is small enough in frame for it not to matter but not much else apart from medium galaxies, which my gear is hardly ideal for.

I do realise total integration time is vital. But with no astro dark right now and maybe only 1130 to 2am being darkish it will take three clear evenings for me to get 6 or 7 hours data. That might mean 3 months