TiffsAndAstro

ty both for this. what's an M6 washer ? also, i could do 5sec exposures on a tripod no tracker would a bedroom light from behind blinds 30ft away create that gradient?

bortle 6 backyard never looked but i checked how to access it and will try and remember er i think this one was siril with drizzle. lens was wide open at 1.7, i was trying last night with it at 2,8 and iso 400 its an old pentax m 50mm f1.7 on a 600d here's a test shot i did last night. 30sec iso400 f2.8 couldn't really do much more cos clouds IMG_5291.CR2

had a frustrating time dodging cloud and rain. 30 seconds at iso400 look promising, but its frustrating doing this through clouds

ty so much for this. Av is the next position on the selector wheel next to manual. Its more than possible i accidentally changed it to Av mode and more than possible after i did, i did test shots and changed the shutter speed via the roller for speed - which also might have changed the exposure compensation to +3. Because im pro 630 to 1030 going to be clear according to my new favourite weather app. With such faster replies on here (who knew ireland had internet? ) i might post an update in a few hours showing my skills or begging for more assistance ty all again !

im actually pretty confident as im sure it was exposure compensation. i just need to be careful not to do it again. i was using the roller wheel to adjust exposure times for test shots. ill do it via bulb and an intervalometer. at least west of ireland has lower bortle to make up for the even worse weather.

i will have a go ty for the suggestion lol

with english weather i think i have to shoot what i can. if i ever get a clear night i could be more choosy if nothing else, my basic set up and quick polar alignment skills are improving trying to google if there's a menu option to disable exposure compensation.

i think i had exposure compensation on +3. possibly. clear skies in maybe 4 hours will have a check then. I'm not intentionally doing anything to the .cr files except copy them across to my pc. i was intending to sort out the crap subs with cloud/trees/aircraft lights before stacking, but couldn't see much ty for this very very useful post. im sure my focus was soft, i was hoping it was 'ok' enough to test longer exposures/my PA etc but i will get it right first. i find it tricky to do, but jupiter should be around and it can help with focus.

btw the moon was out almost full. not within frame, but its obviously more powerful than i assumed. I don't have a lens hood i do have one on a vintage tokina 200mm but want to do better at 50mm before getting too advanced exposure compensation? i did change something a few weeks back which sounds a little like this - but i thought it was to make live view look more like the final exposure? apologies for being rather new at this and ty all for the help. just googled exposure compensation and im pretty sure i didn't mess with this as i shoot in manual and it can't be changed in manual? after grabbing my camera, i think i may have unintentionally had this set to +3. using the roller i thought just changed shutter speed, even in manual mode, but it seems it does that AND exposure compensation? this might be a very good catch ty so much. it would explain a lot i think?

ok so there might be 2-3 hours of clear tonight, my plan is: put my tripod roughly were it was when i took my previous untracked shots (can shoot orion earlier as trees out the way) stop down to f2.8 and do test shots at 5, 10, 20 and 30 sec. if it looks good at 30s sec i might try a test at 60 and 90 seconds too. let it rip until clouds come over. though i may do a similar process for pleiades just before orion, as they come into view a little sooner

lol yes i did

_MG_5127.CR2_MG_5181.CR2_MG_5222.CR2 3 subs one near the start middle and end of the session. will have to delete the stacked result about as its like 900MB in size

hi there ty for all this. yes i can make those files available will update here once i find out how to do that right now im not that bothered about ca in corners and stuff, i really wanted to test out long exposures as that's why i got a tracking mount in the first place. What is most disappointing is i got a lot more of orion nebula and flame nebula stacking untracked 5 sec subs x 100 dss.TIF

both photos are from same lens and camera. i previously had a pentax k-x and got better results stacking 100 x 5 sec subs untracked. this is what i mean from the untracked stack its not great but can see flame nebula and possibly start of horse head.

i think the result is awful, its the result of 103x30sec subs. i got a far better image with a pentax k-x with the same lens on a tripod stacking 100 x 5sec untracked subs. if its clear for a while this evening ill try playing more with fstop and iso values in test shots before setting it to run. ty again.

hey ty for the fast reply. tbh im very new to this (if you can't tell) and im reluctant to stop it down because it will reduce the signal and the light pollution. iso800 seems the best signal/noise ratio. in my focus tests i did drop iso to 100 and it looked 'normal' as i was expecting. i also dropped exposure time to 5 and 10 sec for checking focus and seemed ok then too. But if i can only take 5 sec exposures i might as well bin my tracker. in your experience, is this likely to be caused by light thin high cloud i can't see with my own eyes?

hi there, hoping for some thoughts on the 'final image' ill post below (not a lot more than a quick stretch) and an example of my exposures. Im thinking the answer is high thin cloud that i can't see with my eyes is reflecting light pollution? if this is the case - if i see a test exposure in future like my example below - just try another night? 30sec subs iso800 canon 600d/t3i (unmodified) and an old pentax m 50mm f1.7 shot wide open because im a noob. anyway result is here: and an example sub here: thanks in advance for any insights anyone can provide.

i don't disagree, what i meant was, i want to spend at least a couple of nights of clear skies just getting some experience first. just the idea of a two star polar alignment makes me want one, as i can't see to do this with a gti and synscan app. all the guiding and camera controls on top seem even better. but i want a few hours on the basics before i do that

ty for this, need more experience before considering an asi air

did this happen right after "un hibernating" your mount? mine's done it twice since i got it (two weeks ago). I think, to fix it, after un hibernating i do a one star alignment on something fairly near home. then it seems fine. i haven't updated my firmware since i got it two weeks ago and maybe that update might fix this possible problem?

i think i had a similar issue, it seemed to get a bit lost. i think i corrected it, but clouds came and i haven't seen the sky for like a week.

so an hour or two later it suddenly cleared up, so i set everything back up but this time i couldn't see any stars through the finder scope. checked the caps, RA axis was turned played with the focuser but couldn't for the life of me see any stars let alone polaris. so after some frustration i gave up and used a two star alignment with stars i've never tried to look at before and guessed. took 30 x 30 sec subs of whirlpool galaxy - couldn't see it in the stacked result, but i was impressed with how there was no trailing. so then i told it to go to ngc 237 (i think) and did 30 x 90 sec subs and again, couldn't see my target in the stacked results, but i was amazed how there was no star trailing. clearout says noi clear skies tonight, but bbc weather says 3 hours from 6pm so will have fun again with polar aligning then. all i can think of, as it was so easy to see and align on my first go at polar alignment is that there was a low of dew on the front of the polar scope but wasn't earlier on? there's a lot of top left to bottom right streaky noise on the final image - maybe high cloud? still, early days is is 30 x 90 subs. its crap, but stars look pretty trail free. not sure how tbh.

dunno why its b&w lol - i think i converted it from .cr (canon)? but when i stack them its worked out ok - dss and siril must handle. this was a 30 second exposure at 50mm on a crop sensor when i was trying to work out if it was even tracking stars look pretty round to me

ok i just had 45 mins clear ish skies. i boosted my tripod legs to max, bit wobbly but ok...and polar aligned pretty nicely (if i do say so myself) in about 2 mins. i was attempting a brigh star alignment when the clouds came. after watching another video, i'll try a 3 star alignment on ones i know best maybe orion. tbh im just happy polar alignment didn't seem as bad as i feared. at least as far as i got.

hey ty so much for that. yeah, its expensive and im trying to be cheap as i spent my cash on a gti rather than just a tracker ill have to see how i got on, only got the gti couple days ago and of course its been cloudy ever since. maybe polar alligning won't be too bad....