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alacant

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Hi evryone

We've a cute little 6" for the weekend. Not much to look at but with a collimation tweak and a bit of anti tube flex ointment, it's looking good. 

Not sure about the stars. Once again the blue stars just aren't there. Can't believe there aren't any!

Cheers and thanks for looking,

eos700d 1 1/2 hours @ ISO800

1249552629_1-86-884(copy).thumb.jpg.f5078eab95270d24f0ed649d64194b81.jpg

Edited by alacant
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1 hour ago, alacant said:

Hi

I did once place a post in imaging: deep sky but the help here is better and far less likely to descend into a discussion on which telescope, mount or camera to buy next!

Cheers and clear skies

 

Can beginners give better help than more accomplished imagers. 🤔

May be down there in the DSO imaging section it is a bit more intimidating for DSLR imagers.
I know it was for me, still is because I'm a rubbish CCD imager. 😁

As to the blue stars
A DSLR will quickly saturate most bright stars to white, there may be some colour in the halo.
Drop the ISO and may be the sub length to stop the stars saturating.

Edited by wxsatuser
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You do have blue stars, but as Mike said, drop the iso or exposure a bit so you don't burn out the cores - this is a boost to blue saturation in Pixinsight on your JPG so not the best source of data for me but you can see more blue coming out...

doublecluster.jpg

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This isn't a beginner image. It's tightly focused, well guided and has a flat background sky. Whatever your 6 inch optics are, they are very good. Personally I use nothing larger than 5.5 inches to get 0.9"PP.

Before getting too gung-ho with the blue it's worth a look at the astrophysical data to find the colour index of selected stars. It's available from many planetarium packages (I use SkyMap Pro) and can be compared quickly with a B-V colour index chart like this one. https://www.researchgate.net/figure/Dependence-of-color-index-V-t-mdinstTH-from-color-index-Bt-V-t-for-different-spectral_fig1_275388313  Blue stars have negative or low B-V values, red stars have high ones, as the chart shows. Clearly there's no need to check all the stars in your image but checking a few gives you an idea of your colour calibration.

Olly

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6 hours ago, wxsatuser said:

Can beginners give better help than more accomplished imagers

Good question.

Usually I think, yes. They are closer to the problems beginners face and explain them in terms that they can understand; no acronyms, no jargon, no get-another-camera etc.

Cheers 

Edited by alacant
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12 hours ago, ollypenrice said:

Whatever your 6 inch optics are, they are very good.

paco.jpg.8569ef856c595b435631dc7a17b50f63.jpg

 

LOL, yeah. They'd have to be with me in charge!

But TBH, without the wide dovetail plate, aluminium box section and OAG, it's just like any other mass produced Chinese stuff. Out of the box with a guidescope, I doubt you'd get stars like that.

Cheers and clear skies

 

 

 

Edited by alacant
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