M45 with 1005 frames @ 6 sec, untracked, with 50mm lens

[Jannis]

Canon 550D - EF50mm F/1.4@2.2 - ISO3200 - 6s exposure - 1005 frames stacked in DSS - no tracking.

Mostly I just wanted to put this "number of frames vs exposure time" to the test.

So for the night, i took my normal cheap wobbeling HAMA ($20) tripod with me outside, together with only my unmodded 550D and EF50mm F/1,4 lens. There was a HAMA UV filter attached to the lens - i forgot to take it off, it might have affected the quality a little.

I set this up by focusing using live view, put lens at F/2.2, and found out that 6 sec would be the longest i could do without noticable startrails. I set the ISO at 3200 (wich is the maximum analog ISO for the 550D), and set the timer to take pics none stop with 1 sec break between frames.

Once in a while i moved the camera position a little to put M45 back roughly where it shuold be, and kept on for 2+ hours.

Then i stacked the best 95% in DSS, and ended up with 1005 stacked frames. I stacked using intersection mode in DSS, and Median Cappa-Sigma clipping.

Just for fun, I also stretched a single 6 sec frame to the moon and back just to see what details was hiding in the dark on it.

It's probably still a LOT that could be done to make this better, but it's been almost a half year since i touched photoshop last, so my skills are very rusty (and wasn't too good to begin with either, lol)...

I have not applied any noise reduction in any of the pics.

[VigdisVZ]

Crazy how you can get nebulosity with no tracking! Superb work! Cracking!

[Jannis]

Thanks.

Was planning to save and upload the TIF to dropboks now, but didn't even have time to save it, as photoshop just crashed. All post-processing work lost, lol... >_<

Still have the original stacked though, guess i can do the 30 min photoshop work over again some other time.

[VigdisVZ]

I usually find that a revisit yields a better result as you do things quicker, and have more inspiration to try different things the 2nd time. Still sucks with crashing programs. Command + S was a conditioned reflex back when I used to do layout with QuarkXpress.

[Jannis]

Yepp. I will for sure go for a better 2nd attemp at processing. I know it's more data in there somewhere. And i'm not Too happy with the color balance in the pic when it comes to the stars and background, so I still have a few things i'd like to improove.

Funny thing was PS crashed when i clicked on "save", lol. I wonder though, was median sigma-clipping best option to stack these frames...

But in the end i was surpriced i could get that much faint details out from those very noisy 6s frames. Makes me wonder what i could get if i put camera on my HEQ5 mount and took 30 sec exposures all night instead. Shoudl be able to take ~1000 25-30 sec frames per night if weather stays good.

[VigdisVZ]

Considering how good I think my M45 was with 33x30sec lights, you should be able to work pure magic if you keep at it.

[tingting44]

lovely detail in this mate, with only 6s subs!!! one thing....do you use mirror lock up? to avoid mirror shake when the DSLR takes the pic, i find i get loads better quality pics when i have mirror lockl on, but it adds so much time i have to put 5 secs inbetween for the mirror to stop giving off vibrations and when its on the timer shutter, if i tell it to take 200 subs, i will only end up with 100 subs. as 1 click on the timer shutter release locks the mirror (then 5 sec interval) then a 2nd click which actually releases the mirror and take s the sub,

cant wait to see some more of your experiment s mate, great stuff!

[Jannis]

Thanks.

I use mirror lock-up yes.

I use magic lantern firmware, and had it set to take 6s exposures every 7 or 8 sec (can't remember wich, lol), so i had 1-2 sec wait time in between.

Normally i use 3-5 sec when i use the 1000mm scope, but this time, as i only used a normal 50mm lens, i wouldn't really have had to have any waiting time at all. But I still set it to 1-2 sec just to be sure as my tripod was really wobelish (i'm sure if you looked hard enough at it, it would fall apart, haha).

I'm planning to do a similar attempt at M42, but that will be at a later time as i'm too busy these days.

I'm then planning to give it a try at F/1.4 (regardless that the stars don't look nice at all at 1.4) and try to also catch some of the bernard's loop. Don't know if it will work though, but worth a try anyway...