Sorry but another

[Hagar]

I know everyone is sick of M83. I was in two mind about posting this one for a couple of reasons. Firstly I do hope to capture some RGB data for this and secondly there has been quite a few M83 of late and this was nothing special.

I have done just a quick stretch on this image and took a look around the starfield around the galaxy and behold a huge number of small galaxies poking through the dark so I thought it was worth posting and well worth having a look at the high res image.
There also appears to be what looks like a small PN around one of the stars but I can't find it listed anywhere. You need to look at the Hi Res version to see it. Right hand top.

The image is a combine of 10 X 15 minute subs captured with QHY9, Baader Lum filter and Takahashi FSQ106ED at f5. I love this scope.

High Res Version HERE (http://www.darkskyau.com/cm/displayimage.php?pid=316&fullsize=1)

[Ross G]

Hi Doug,

I could never get sick of looking at galaxy photos and M83 is such a beautiful galaxy.

Your photo is so sharp and full of detail.

Thanks.

Ross.

[multiweb]

Great picture. So sharp. Looks real nice in that field of stars. :thumbsup:

[allan gould]

Doug
I really like your shot. Sometimes I just prefer black and white because to be honest, that's the way our eyes perceive the scene. Really great feeling of space with that galaxy just floating there.

[Bassnut]

Tac sharp (pun). Many stars, M83 a bit small for your (WW) rig?.

[[1ponders]]

That's lovely Doug, the mono really does it for me. Its a great FOV with that scope as well. Nicely done :thumbsup:

[atalas]

Very nice Doug.

[Hagar]

Thanks for the comments Guys. The black and white does allow for a few nice bits of detail to show through without burrying it in colour.
I am interested to see if any of you can come up with what the ring around the star in the top right actually is.
You really need to look at the Hi res version to see it properly.

Thanks Fred, yes a small target but I am happy how well it resolves even at this focal length. It does allow for a crop which I haven't done as yet.

I have also included a crop of the ring around the star.

[jjjnettie]

It's a cute little ring around that star. Let us know when you find out what it is.
And one can NEVER get enough of M83. LOL
Love it.

[[1ponders]]

Its not actually a star Doug but a galaxy PGC47964 (according to The Sky 6)

[TrevorW]

Never tire of M83, you've done a good job on this one Doug

[Hagar]

Thanks JJ.



Thanks Paul, I didn't have a look at The Sky. I only looked in Starry night but with the galagy database turned off.

[Hagar]

Thanks Trevor, I hope you can still say the same after I add some colour to this luminance shot.

[TrevorW]

We will see, waiting in anticipation for the next episode

[batema]

That is a beautiful shot. It is probably a dumb question but do you use a field flattener or is the shot from the scope as it comes out of the box with nothing added.

Mark

[gregbradley]

A beautifully sharp image. Those stars are pinpoint.

Greg.

[Hagar]

Looks like you might have to wait a while longer Trevor. I just did 3 lovely hours of 2X2 binned Luminance as the power supply lead had fallen out of the filterwheel. I don't know when I will get another chance. Maybe next week as I am back at work ntomorrow night. I should stay up all night but I need some good sleep before starting work again.



Thanks Mark. The image is persay straight out of the box. No flattener is required with the FSQ as it is a flat field astrograph made especially for imaging with a quadruplet lens cell to keep the image flat.



Thanks Greg, I did spend a bit more time getting my focus right and getting the scope down to temprature before I started. I also adjusted the focus after each set of 2 images so every 30 minutes. It didn't need much adjustment anyway so waiting the extra hour before starting was worth the effort.

[TrevorW]

Excuses,excuses !!!

[Paul Haese]

Incredible for the resolution. Stars are really nice and round and despite being monchrome the image shows a lot of detail. Maybe some selective sharpening might be in order. Looks forward to the colour version.

[gregbradley]

You raise an interesting approach with the use of refractors. They do have a cool down time. I was wondering about that with mine. Not sure if you take yours out from a warm house into the outside? Mine is usually setup in an observatory but there is the temperature drop after sunset to contend with.

FSQ is well known for its relatively high sensitivity to temperature and focus shifts. Perhaps a consequence of the Petsval lens setup.
You can train a Robofocus for temperature compensation and have a thermometer attached. That way it takes care of it automatically and even during the exposure if its taken during a period of temp drop.

Every 1C drop in temp in an FSQ is slightly visible in temp shift. 2C for sure. A little digital thermometer next to your setup would be handy for that and if the temp was stable there should be no need to refocus but if different by 2C then a refocus is needed by a small amount.

Its worse when using the reducer. Slightly off focus with the reducer makes for a lousy image.

Greg.

[Hagar]

No excuse, just another stuff up.



Thanks Paul. Now I have to compete with the moon for some colour. Maybe next new moon.



Hi Greg. Yes the FSQ is definitely a focus beast requiring a bit of work to keep focus but I have found that delaying the start of my imaging by about an hour gives me a much better chance holding focus for a while.

I have tried temprature compensation but found I spent just as much time confirming or fixing focus as I do doing a manual focus every half hour to hour.

The quality of the scope make focusing worth the effort though. It's a keeper for sure.