Finally got around to M33

[poogle]

Have been wanting to image M33 for quite some time now, and finally got around to it. Lots of high thin clouds and a bright moon, but I managed to get 1 hour of data.

With the low surface brightness of M33 and only 60 x 1 min subs I'm pleased with the image. I had to stretch the image quite a bit to bring out the detail I wanted, which resulted in a noisy image and not the best background...guess I need more data

I had to image unguided since my QHY5/finderscope is currently hooked up to my Raspberry PI (I'm trying to build an autoguider so I wont have to bring my computer every imaging session).

Lights: 60 x 1 min @ ISO 800

Darks: 30, Flats: 30, Bias: 30

Processed in PixInsight

Thanks for looking, any feedback appreciated

/Patrik

[LouisJB]

wow, looks fantastic, especially since you were unguided. Nice job!

I think this may be my next target. It's quite dim isn't it. If you had guiding working, what length lights would you have gone for do you think?

[poogle]

Thanks for the kind words! Yes, it's quite dim, but it turned out brighter than I would have expected

Well, with the moon up and Stockholm light pollution maybe I would go for 2-3 minutes. Without the moon I think 5 minutes would be my limit without traveling to darker skies.

/Patrik

[Astrosurf]

That's an excellent image considering your difficulties. I'd be very pleased with that! You can always add more subs at a later date.

Alexxx

[jarlaxle2k5]

beautiful !!!

I will try it

[DrRobin]

Very nice, not an easy target it would seem.  I had a go at this last night.  Took 40 x 3 min @ 800 ISO, 20 darks and 10 flats.  I might have teased a bit more detail out but certainly didn't get as much colour as you.  All of my stars are white.  I used an 8" newt (F/4) and IDAS filter.

Robin

[poogle]

I guess it's easier to keep star colour during processing for me @F5 60 sec compared to your 3 min subs @F4

Have you tried a star mask to prevent "overexposing" the stars during stretching?

I didn't need one for my subs, but I did a saturation boost with a luminance mask which helped bring out the colour.

/Patrik

[lensman57]

Very well done for such short subs with a DSLR, just imagine what 60X180s subs would look like.

Regards,

A.G

[DrRobin]

Hi,

I had a go at boosting the saturation and stretching the image and made it a lot better.  I must develop a few more skills in DSO imaging, getting decent subs seems to be only half the battle as I have tried processing this a variety of ways over the last couple of days, the best so far is below.

I guess it's easier to keep star colour during processing for me @F5 60 sec compared to your 3 min subs @F4

Have you tried a star mask to prevent "overexposing" the stars during stretching?

I didn't need one for my subs, but I did a saturation boost with a luminance mask which helped bring out the colour.

/Patrik

Do you loose colour with longer exposures?  I might try M33 again with 60 seconds, it certainly makes it faster to get a few subs.

Robin

[Pete Presland]

thats a pretty good image for 1minute subs, like you have said if you get upto 3minutes you will have to stretch it as much, but certainly nice going so far.

[poogle]

That's a lovely shot Robin, less noise and more detail than mine! As you say, processing skills are really important. I spend spend more time processing than acquiring data, and I'm still at the bottom of a steep learning curve

What I meant regarding colours is that you're more likely to overexpose bright stars the longer subs you use, resulting in bloated white stars instead of small coloured ones. I have seen some imagers take shorter subs just for the stars and layer them on top of the DSO and some seem to keep the colour using masks during stretching. That being said I think your stars look really nice and colourful!

Thanks AG and bunnygod, I really must get my Raspberry PI autoguider project going so I can guide again

/Patrik