x6gas

That's a wonderful image of a target that's a new one on me...  most excellent!

Lovely image of the Wizard Mark - you've brought out the OIII exceptionally well.  Well done.

It’s up and running and capturing data and was the subject of the StarGazine talk last night.

Narrowband data of M16 will be released shortly.

17 hours ago, callisto said:

Fantastic image 👍...........I want a Quark Chromosphere now 

 

Mark

Thanks Mark.  I've only managed to use the Quark twice so far and I'm not confident I have it working optimally yet but it's promising.  It is certainly a thrill to see a big prominence... and I'm looking forward to improving.  Thanks for the encouragement.

19 minutes ago, andrew s said:

I don't  agree as per my diagram in the linked thread you need to increase  the back focus distance by 1mm.

Regards Andrew 

I agree with you Andrew.

2 minutes ago, Astrosharkey said:

If you are using a filter wheel as described above its internal to the wheel and doesn’t effect the distance

I don't believe that is the case as it's refraction due to the filter that pushes the light cone out.

Cheers, Ian

To be honest Gary it depends on your setup.  Longer focal lengths will probably be more forgiving but it depends on other aspects too.

I suspect that the spacers you suggest will be absolutely fine but the thing to do is to actually image with that spacing and check the results which will tell you whether the spacing is too close:

or too far:

It's a question that seems to cause a lot of confusion.

Here is the example I gave which I hope explains it: 

For my FSQ85 reducer I need a spacing of 72.2mm.  If I have a 3mm astrodon filter in the image train it pushes the image cone outwards by 1mm so the spacing requirement is increased by 1mm to 73.2mm.  You are ADDING to the back focus requirement.

So to make that 73.2mm I have:

Atik OAG: 24mm

Atik EFW2:  21.8mm

Atik 490: 13mm

Spacer:  14.4mm

=73.2mm - the impact of the astrodon filter has been taken into account by increasing the required back focus distance.

Now alternatively you can include the impact of the filter on the imaging train calculation by including it as follows:

Atik OAG: 24mm

Atik EFW2:  21.8mm

Astrodon filter: -1mm

Atik 490: 13mm

Spacer:  14.4mm

=72.2mm

In this instance you are SUBTRACTING the impact of the filters on the elements contributing to your backfocus.  It might help the penny drop if you calculate the spacer required in both of the scenarios above.

More on this thread: 

Very many thanks Mark and Pete and huge thanks for the tips @Rusted.  I'm still not sure if the Quark is working as it should but despite very hot weather (which I guess is also appalling for seeing) it's actually been pretty cloudy here... but those are great tips and I'll bear that all in mind.

I'm just making an extension tube on the lathe so that I can dispense with the diagonal and have one less surface in the image train.  Also Gary Palmer made the point that it keeps the camera out of the sun which I guess isn't a bad thing...

Thanks again.  I am encouraged by my first couple of attempts!

Cheers, Ian

Well that is just astonishing.  You should be expecting a visit from Edina and Patsy because that is absolutely fabulous.

Super image Richard.

Very nice Alan, thanks for sharing.

The Esprit 150 is a lovely scope isn't it...

Nice images Adam.

39 minutes ago, rodrigol said:

Thanks for watching and for the advise! Yes, I need to be brave and get longer exposures and let the dithering do it's job. Still learning but I know the galaxy arms stretch beyond the mag 10+ double HIP 48635 stars.  I also have the issue with the CA on the east side of the pier, which I'm afraid may be due to mirror flop? I do focus often to get things tight but I'm beginning to see this more often when I image on the east side of the mount...

Hmmm.  I hadn't really thought of this before but I guess the collimation could be changing either side of the pier...

Nice result for just 30 minutes total integration time.  Obviously this target has a lot more to give with more data.  It's interesting to see the chromatic aberration you are getting around the brighter stars.  I get this too using a mono CCD on my Edge 11 but can tame it a bit by aligning the frames using RegiStar...

Agree that is fabulous for less than an hour's data with a DSLR... and your 4th DSO too!

Congrats!

Hi all,

Inspired by the great StarGazine talk by Gary Palmer, I bought a Quark Chromosphere from FLO and have been taking my first, somewhat shaky, steps in Ha imaging of the sun.  I've got a lot to learn.  This is the second Ha image I've processed and the first I have posted.

Was really thrilled to see this big prominence on Friday and managed to capture a couple of videos.  Interestingly (to me anyway) the image was much more stable at around 18:30BST than it was earlier in the day despite the light having more atmosphere to traverse - is this common?  I'd read that things can be more stable first thing in the morning as the air has not yet become so heated which makes sense...

So this image is a composite (one video for the chromosphere, one for the prom) of the best 200 frames of 1000, stacked in AS!3, wavelet sharpening in RegiStax6, and final processing in PS.  I used a mixture of techniques described by Gary Palmer and Marty Wise ( @MalVeauX ) and found both extremely helpful so thanks guys.

TS90 CF apo, Baader 7.5nm filter, Quark Chromo, Celestron Skyris 236M

I left plenty of orange in the background sky deliberately, but I am new to this so critique, comments and suggestions to help me improve most appreciated.

Cheers, Ian

@Elio_C you can easily spend AU$6,000 on even a small aperture refractor, double or treble that on an equatorial mount, and hundreds of dollars on each eyepiece.

No one does that on a first telescope - and that's OK.

You're doing the right thing in asking questions and I think you should do as you are doing: set a budget and find kit that meets your needs and your budget as best as possible while accepting that there will be compromises.

With your budget I wouldn't personally be thinking of spending big on an eyepiece.  A long focal length scope will do you just fine for solar system observing and even a low quality 20mm plossl will probably be just fine to start with.

Nothing wrong with wanting a scope instead of binos.  Quite understand.  I want an obsy dome even though I know a roll-off roof makes more sense.  I don't care!

I don't know Saxon as a manufacturer but words like "for children" in the description of the cheaper one doesn't inspire too much confidence.

It's easier to make longer focal length telescopes that suffer from *less* aberration than shorter ones, but the native magnification is higher so you'll need a better mount to make the most of that.

I would also suggest the same Skywatcher scope mentioned above.  A well known brand with better resale potential (here in Europe at least) and it could serve as a guidescope in future if you get into astrophotography.

I'd also suggest checking out Astronomy Tools FoV calculator to get an idea of what you'd see from the eyepiece (in terms of field of view, not quality of image!)

Beautiful.

That's very nice.  To be honest I have nothing but admiration for anyone managing to image from the UK at the moment... I've been clouded out for weeks.

It's a pretty target, though, and a new one on me so thanks for posting.

In that most recent version it looks like the broom is on fire... which is kinda cool.

But, I have to say that they all look over stretched and over processed to me if I am being honest, Neil.  It's hard with this nebula as it inherently appears pretty harsh to my eyes.  Each to their own, though, and I don't think my taste is very typical!

Well Affinity Photo is the newish kid on the block that seems to be getting some traction...

I have some problems with it as its macro feature isn't anywhere near as good as Photoshop's actions and there are one or two other limitation like fixed sample points only reporting single pixel values (rather than a multi-pixel average) that are really annoying.  But for a capable, layers-based photo editor it's great for the price.  Nik Szymanek is doing a series on it in Astronomy Now...

On 27/07/2020 at 18:59, ollypenrice said:

There is an old English saying: A poor workman blames his tools. That might be me!!!

Thanks for your input.

Olly

You Olly? Quand les poules auront des dents!  I was suggesting the complete opposite.

35 minutes ago, ollypenrice said:

Binning RGB? I can see why people do it but here's why I don't: I want star colour to go deep into the stellar cores. If you want it all the way in you won't get enough faint colour, but colour going well into the cores can be dragged further in by processing. If you bin your colour (assuming reasonable sampling rates since huge over sampling will negate this point) you will probably burn the cores to white which is precisely what you don't want to do. So... not only do I not bin colour: I also shoot it in 10 minute subs rather than the 15 to 30 I use for luminance. This is effectively the absolute opposite of binning colour. And it brings another bonus. In my RGB layer I have, in effect, a set of 'short' subs for regions over-exposed in the L layer. There is no reason not to use my far less exposed RGB layer as less exposed luminance. In Ps you don't even need to convert it to greyscale. You can apply RGB in blend mode lulminance.

I'm really interested in this.  Recently, for broadband targets, I've only been shooting RGB and no luminance.  Making a synthetic luminance from all of the RGB data has helped but I am now convinced of what was probably obvious in the first place: better results from shooting good quality luminance.

I was assuming that I could bin the colour, as I have done with some success in the past, shooting really short subs - 180s or 300s at most (depending on the scope) because you can stretch the data and then do heavy noise reduction or blur it under the luminance layer.

However, if I read Olly's post right, he's suggesting there is some fidelity in the RGB that is useful both in the colour data itself (giving graduation from core to halo, that maybe wouldn't be present in a heavily blurred RGB) but also the tip to provide less exposed luminance is something I hadn't considered...

More tricks than Paul Daniels 🙂