TiffsAndAstro

I agree with you and hope you're right. Better to learn to powerslide in a Mazda rather than a Ferrari. Though maybe substitute good condition trabant for the Ferrari in my case

Tbh I was starting to wonder how others in similar light pollution could take even longer exposures, but just stopping down might account for it. Also filters and likely other factors. Would f6.3 on my 200mm be worth a go ? I don't see many 200mm/320mm f6.3 telescopes about

one image of an example histogram m42 f4 90sec iso 400 (i think, sorry need to make better notes as i go) one image of plate solve for (i think it was) m42. took a few goes i might have my target accuracy (can't remember exact name) set a bit too ambitiously if anyone can give any useful insights from just these two jpgs i'd be grateful. and impressed

its only up to about 1/3 the way from the left. not even halfway across. ill try and take more pics on my phone next time its clear. didn't have time to do more than set up polar align plate solve m51 thena couple of exposures on my 135mm stopped down from 2.8 to 4. after a while there were some gaps in the cloud so decided to experiment with my 200mm, stopped down from 3.5 to 5.6. it seemed very dark, but with a bit more time to focus, might be my least [removed word] lens. too early to tell. im quite happy i seem to be able to 3ppa reliably (with various focal lengths) and plate solve too. hopefully getting a reasonable lens is all i need to get better results. and some clear skies.

its only up to about 1/3 the way from the left. not even halfway across. ill try and take more pics on my phone next time its clear.

they were only 90 seconds, but, as you say, any problems could be hidden by trailing and stuff, so as soon as next clear nights ill give it another go with maybe 5 sec subs and stopping it down, but im looking to try and get a more suitable lens to use. also, im bortle 6 (somehow) and im not too experienced with how light pollution varies with exposure and sub time and wonder how to achieve a happy balance. hopeful this will come with time under clear skies and lots of swearing.

apologies .cr2 are a bit weird to convert.

600d/t3i (unmodded) sky watcher gti plugged into nina those images attached above were taken with an old 135mm f2.8, but i also have a pentax 50mm f1.7 a tokina 200mm f3.5 and a centon 500mm mirror lens also 18-55mm kit lens which i haven;t tried since i got my tracker. its a bit wide field of view to shoot stars and avoid trees and roofs and a bit slow. maybe i can get its autofocus to work with nina? the pentax seems by far the best image quality of them, but not much zoom

no comment ok i lied redbull gives you wings 2024-03-18_01-50-33__15c_90.00s_0000.cr2 2024-03-18_02-44-39__19c_90.00s_0007.cr2

also while looking at results of "how much pa is good enough" search, i saw a really good quote which seemed very apt: measure with a micrometer, mark with chalk, cut with axe

honestly, i realise i am very, very new to this hobby but i don't think i could agree with you more. i think my entire gas for this hobby demands its because of my unrealistically limited budget. the mount most people agree is the most important so i spent most of my budget on that. every other bit of equipment is cheap and nasty by comparison, but they at least allow me to practice stuff and connect stuff and one day, long after the heat death of the universe, have everything ready to go for when i can find a decently sharp, fast cheap lens. delivered in a free Ferrari. my 135mm is not good. after really getting focus down via live view in nina and then quick test exposures they look awful wide open. i cba closing it down much because what's the point? so my remaining budget will go on stuff in this order: ok ish lens, better tripod, cheap guide scope and cam and some sort of mount/bracket. ill attach a couple of subs when i get home of what isn't acceptable which is aberation of the stars and/or tricky focusing. ill try out my 200mm f3.5 next clear skies and see it is not quite as bad as my 135

didn't do this and will give it a go tomorrow, though its possible clouds will clear a bit in an hour or so

Just in case anyone's wondering, I think less than 1 minute should be plenty for me. If there's a gap in the cloud tonight will see how quick less than 1min takes. Theres a chance I can get the comet and triangulum galaxy in same frame at 135mm

Well I found shiny thing and found i could focus on its reflection. No use for fixing bird shapes but, I could watch that focus change as the purple fringing was replaced with green fringing I think that will help me focus when it's dark though. I'd say the fringing doesnt really change much even stopping down to 6.3

Ty all for all the solutions. I'm sure at least one will do the job. The flashlight thing from flo seems a great idea at a decent price.

I remember seeing the sun on television a few months ago.

Is there anyway in daylight or a cloudy night, to test my lens at various stops to see how it effects aberations? I'm thinking bright led behind foil with a pinhole at one end of garden and 30feet away at other?

first clear sky attempting 3ppa with nina went really well, laptop battery life and shiity 25 year old usb hub issues aside whether my pa was as accurate as nina said who knows. next clear skies ill repeat it and try some very long exposures to test it? i was only using a 50mm lens, so im not sure how accurate 3ppa really can be with a big fov.

just in case anyone is interested and/or haven't tried nina for 3ppa.... it was drizzling, so i go play warthunder. go for a cig 20 mins later sky perfectly clear. so i hurried set up my gear, plonk tripod point north (i couldn't help having a glance through polar scope to check polaris was at least somewhere in view). connect my laptop, all goes fine but plate solving, error about couldn't download image. tried camera not going through an old crap usb hub and it worked:) did all 3 polar alignment image and solved them and gave me a reasonably small error, but no matter what i did with alt/az bolts, the error didn't change. took me 10 minutes before i looked up and noticed sky full of cloud which i am hoping was the problem. 95% 3ppa on nina, first attempt and only failed due to cloud....i hope ok so clouds went away battery charged up a bit and camera battery changed, had another go. wow. its a bit fiddly (my mount bolts are pretty nasty with a weird dead spot on the alt). got it seemingly good, tightened the big bolts and alt and az both went up to like 3 or 4 minutes. tried again on both and got the screenshot below and left it. what sort of numbers are good enough? is there a chart somewhere of like focal length, exp time, guiding yes/no etc? also anything anyone notices i should change. i couldn't see a way to change delay between 3ppa subs. ive set it doing a sequence (i think) of 20 x 120 sec on m51 at 50mm crop sensor lol just to test if i can repeatedly set up as quick and accurate (?) as my last attempt, nina is pretty amazing also want to preview my subs but scared to break anything, my choice of colour screen needs work

Tbh I've only really run provided scripts, but would love this so tyvmuch. If I ever see stars again I will have a go. Using dss like I do is a pita. Seems I'm blind to clouds in subs. Aircraft I can spot

Honestly, I bought a 135 2.8 200 f3.5 500mm f8 and tmount to ef adaptor for £60. I assumed they'd be a bit [removed word] compared to £500 scope but wanted at least a couple of hours getting an idea of relative focal lengths before committing a bit more. I think they've been worthwhile for that. But I cant un see the birds stopping them down does help. My dad's old mint 50mm pentax m f1.7 seems fantastic in comparison.

100 seems much more do able ty

Sy135 seems too much but will keep looking.

SW 72ed is on my list but would need a flattener? 200 earth poinds on flo I think I would like its colour coordination however. Possibly a tad heavy on my sw gti as I'm keen to mess with auto guiding.

I have vintage 135 2.8 and 200 f3.5 and the stars show a lot of bird shapes. Less so if I stop down, but then it feels like what's point of a fast lens if I have stop it down? I'm guessing that's why we have proper telescopes. As a noob, I'm keen to delay experiencing the fun of back spacing etc