NGC1316 with ED80

wasyoungonce (Brendan) · #1 08-01-2010, 02:49 PM

A difficult target for an ED80...ambitious to say the least.

52 x 5 min ISO800 lights (4.3hrs). 13 Darks (from a previous night) & 10 flats (my 1st attempt at flats, twilight flats). ED80 guided with ZS70ED on G11/gemini, canon 450D.

Moon light kinda spoiled 1/2 the exposures but I kept them. I couldn't do new darks as my camera battery was "kaput"!

I've designed & built a 12V to 8V PSU for the 450D with under/over voltage protection but I'm not happy with it (the linear regulator) & have new generation linear regulators with current sense & shutdown protection ..on the way!

I counted 18 other galaxy's in the frame.

Anyway...for what it's worth.

AG Hybrid (Adrian) · #2 08-01-2010, 02:56 PM

Quote:

Originally Posted by wasyoungonce

A difficult target for an ED80...ambitious to say the least.

52 x 5 min ISO800 lights (4.3hrs). 13 Darks (from a previous night) & 10 flats (my 1st attempt at flats, twilight flats). ED80 guided with ZS70ED on G11/gemini, canon 450D.

Moon light kinda spoiled 1/2 the exposures but I kept them. I couldn't do new darks as my camera battery was "kaput"!

I've designed & built a 12V to 8V PSU for the 450D with under/over voltage protection but I'm not happy with it (the linear regulator) & have new generation linear regulators with current sense & shutdown protection ..on the way!

I counted 18 other galaxy's in the frame.

Anyway...for what it's worth.

4.3 hours of exposures. Difficult is an understatement. The tracking is superb

. Is that sort of brown color ihn the background the result of the moons light pollution?

wasyoungonce (Brendan) · #3 08-01-2010, 03:14 PM

Quote:

Originally Posted by AG Hybrid

Is that sort of brown color ihn the background the result of the moons light pollution?

I suspect it's my processing skills & pushing 450D ISO800 5 min exposures.

TrevorW · #4 08-01-2010, 03:43 PM

Unusual, strange, different

Apparent mag 9.4

difficult to say the least for the 80

AlexN · #5 08-01-2010, 04:13 PM

Very nice wide field full of galaxies, if you convert the image to monochrome and invert it, the faint galaxies become very apparent!

I really like it... I love seeing wide fields of bunches of galaxies.. Shows of the vastness of the universe...

Trevor : Telescope optics make little difference to the magnitude of the objects you're able.. It would if you were trying to spot it visually, but for a camera, it just means longer exposure... an ED80 could get down to magnitude 20 if you had the right camera and expose long enough.

hotspur (Chris) · #6 08-01-2010, 04:42 PM

its amazing what can be done with 'off the shelf' equipment today by

dedicated amatuer astronomers,amazing to see 20 galaxies !

well done!

rogerg (Roger) · #7 08-01-2010, 04:43 PM

Nice to see a wide field galaxy shot, good effort

I wouldn't consider the subject a hard target for the scope, but combining the scope with an un-modded DSLR it gets tricky

Could you push your exposures out to 10 mins? If it were me I think I'd have gone for half the number at 10 mins. But Depends on many factors that only the photographer can judge

It looks like you have some kind of issue with your darks, shown by the "dark rain" in the background (trailing dark pixels). With my DSLR I usually get this when dark frames are correctly matched to the light frames (usually by way of different chip temperature).

It looks like you could improve it by removing a gradient also, brighter at the bottom than at the top.

wasyoungonce (Brendan) · #8 08-01-2010, 05:11 PM

Thanks Gents. It's a small target and not easily definable but the up side to me was the large cluster of galaxy's. I didn't expect this.

Funny enough I could see the main galaxy blob with the guide scope, WO70ED & QHY5 camera on 2 sec exposures, repeating.

I took this up to 10sec exposures just to play and the the main galaxy blob was very definable.

Anyway it tracks well & I need a field flattener...when I can save up enough. I'll revisit this when I get my C8 up & running. I'm waiting on a guide scope dovetail..again when I save up. Maybe F10 will do it justice.

This will test the mount & tracking!

TrevorW · #9 08-01-2010, 05:12 PM

Alex I was referring to the light gathering power of the ED80 and the wide FOV, sure you can capture MAG20 objects but these require long exposure times and mulitple stacked images but you still end up with limited detail

As an example attached is the Hubble image of the same object

I not negating the time and effort taken too capture the image.

AlexN · #10 08-01-2010, 05:38 PM

Thats an affect of resolution, focal length and the lack of atmospheric disturbance as opposed to aperture... which is a whole different thread rather than clogging up this thread with irrelevant information..

wasyoungonce (Brendan) · #11 08-01-2010, 05:49 PM

Quote:

Originally Posted by rogerg

......... Could you push your exposures out to 10 mins? If it were me I think I'd have gone for half the number at 10 mins. But Depends on many factors that only the photographer can judge

It looks like you have some kind of issue with your darks, shown by the "dark rain" in the background (trailing dark pixels). With my DSLR I usually get this when dark frames are correctly matched to the light frames (usually by way of different chip temperature).

It looks like you could improve it by removing a gradient also, brighter at the bottom than at the top.

I haven't tried any longer than 5 min exposures. I thought I'd get too much "noise".

The Darks were used from a different night as my battery went flat and I had no camera power. I'm thinking of taking just the camera out & taking a swag of darks one night...trying to get them at different temps and make a file list of darks. maybe use these & replace them every few months or so.

I suck at processing. After DSS stacking the image (especially the background) is quite bright, especially on ISO 800. Even after dark subtraction.

I am fiddling ATM trying to set white & black points but...the whole DSS tiff was too bright to set the white point correctly. Attached is the orignal pic saved as an 8 bit jpg. Maybe you can see how "washed out" the image looks.

I need to mod my camera...I have the filter...I used to teach F111 reconnaissance camera courses & was in charge of recon camera repairs for a few years...so you reckon I should be able to handle this task....!

But...it's my money at stake here...not the governments

.

I'll do it soon. Shame on me!

toryglen-boy (Duncan) · #12 08-01-2010, 11:24 PM

thats a great image, the focus and tracking are both exceptional, the detail visible in the background is fantastic

congrats, you gotta be happy with this

Hagar (Doug) · #13 09-01-2010, 09:25 AM

Very nice image. Small galaxies can be dificult with a wide field scope. The resolution just isn't there with an ed80 or even my FSQ106ED. To achieve a great galaxy you need focal length.
I like these wide field, galaxy field shots, it's nice to spend a while just looking around at the dim little background galaxies.

Nice image.

wasyoungonce (Brendan) · #14 09-01-2010, 10:07 AM

I was very naive in expecting a larger central image...I didn't use ccd calc to find the image scale prior to this pic...so I didn't know what to expect.

It's no great leap in Astrophotography but it does give me an idea of my limitations.

Maybe something larger? Maybe I should have used the WO 70ED as the image scope instead of the guide scope? Wider field, faster F ratio?