Lovejoy and Pleiades again

gregbradley · #1 24-01-2015, 06:58 PM

I experimented with various exposure lengths and ISO's and decided the best results would come from building up signal (exposure time) rather than ramping up amplification (high ISO).

This is a single 10 minute exposure at ISO 200 Sony A7r.

http://www.pbase.com/image/158919897/large

Greg.

Bassnut (Fred) · #2 24-01-2015, 07:09 PM

Thats different, excellent Greg. Sort of racy compostition.

gregbradley · #3 24-01-2015, 08:17 PM

Quote:

Originally Posted by Bassnut

Thats different, excellent Greg. Sort of racy compostition.

Thanks Fred. It gets pretty low to see over the walls of my observatory now and it was getting pretty low here. One of the last opportunities to image it really.

Gre.

RickS (Rick) · #4 24-01-2015, 08:37 PM

Yes, nicely done, Greg.

graham.hobart (Graham stevens) · #5 24-01-2015, 08:55 PM

That's actually quite a shot. Has motion in it. Beautiful.
Thanks for the look
Graham.

dvj (John) · #6 25-01-2015, 04:38 AM

Excellent shot Greg! Like zero gradient in that image. Was it corrected? how do you like the A7s?

j

gregbradley · #7 25-01-2015, 07:04 AM

Quote:

Originally Posted by RickS

Yes, nicely done, Greg.

Cheers Rick.

Quote:

Originally Posted by graham.hobart

That's actually quite a shot. Has motion in it. Beautiful.
Thanks for the look
Graham.

Thanks Graham. That aspect did work out well.

Quote:

Originally Posted by dvj

Excellent shot Greg! Like zero gradient in that image. Was it corrected? how do you like the A7s?

j

I am very Trixie John! Yes its corrected.
I have an A7r which is the 36mp A7 model. Its much like a Nikon D800 but way smaller. Its actually a bit brighter than the D800 at ISO6400 for some reason. Not massively but noticeable. The noise pattern is better on the Nikon, colours and everything else except autofocus I prefer on the Sony.

Greg.

atalas · #8 25-01-2015, 07:15 AM

Wow!thats a long tale....well done Greg.

gregbradley · #9 25-01-2015, 08:20 AM

Quote:

Originally Posted by atalas

Wow!thats a long tale....well done Greg.

Yes its massive, isn't it.

Its somewhat of a visual object as well. Its now below the Pleiades and to the left of it. Last time I imaged it - 2 nights ago, it set around 11pm behind my rear mountains which take up about 15 degrees of my western horizon.

Greg.

Ross G · #10 26-01-2015, 11:21 PM

Great photo Greg.

You have captured the long detail so well.

Ross.

ralph1 · #11 26-01-2015, 11:33 PM

Very long tail; the stars are slightly red for my taste though. It would be pretty cool to take photos from the same location with the background in focus and combine them if it's possible.
Ralph

gregbradley · #12 27-01-2015, 08:13 AM

Quote:

Originally Posted by Ross G

Great photo Greg.

You have captured the long detail so well.

Ross.

Thanks Ross. It also took some tricky processing to bring it out more.

Quote:

Originally Posted by ralph1

Very long tail; the stars are slightly red for my taste though. It would be pretty cool to take photos from the same location with the background in focus and combine them if it's possible.
Ralph

I may have a background shot I took as well. I'll have to check if I did that for this exposure. I know it did for some. There are quite a few yellowish stars that have a bit of a red ring. Probably some chromatic aberration of the lens. I can tone it down a tad but often in the sky there are patches of yellow stars. It probably is a tad red I agree. I was happy there was colour in the stars as that is the first thing that goes with high ISO shots compared to long exposure and low ISO. It preserves the colour.

Greg.

bwana (Brian) · #13 03-02-2015, 12:49 PM

Quote:

Originally Posted by gregbradley

Cheers Rick.
Thanks Graham. That aspect did work out well.

I am very Trixie John! Yes its corrected.
I have an A7r which is the 36mp A7 model. Its much like a Nikon D800 but way smaller. Its actually a bit brighter than the D800 at ISO6400 for some reason. Not massively but noticeable. The noise pattern is better on the Nikon, colours and everything else except autofocus I prefer on the Sony.

Greg.

Here's a comparison shot off the A7S:

https://lh4.googleusercontent.com/-V...Lovejoy-PI.jpg
Canon 200mm f/2.8, Hutech HEUIB-II filter, full spectrum Sony A7S, Celestron AVX mount, 51x30sec @ ISO 3200, preprocessed in PixInsight, postprocessed in Lightroom

A few more shots at:
Comets & Asteroids

Lovejoy was one of the best we've had in the northern hemisphere for a lot of years. You've had a few great ones more recently!

bwa