SilverAstro

15 minutes ago, JohnSadlerAstro said:

My HAPPIEST post ever!!!!!!!!!!!!!!!!  

I have 16-bit GIMP now!!!!!!  It's amazing!

I am soooo excited right now.......

Yea !! I am so happy too, yet another keeper of the GIMP flame preserved in the camp

and for your next trick you'll be trying out the Gaussian blur tool to get rid of your muddy SW

PS I didnt explicitly say so earlier but IRIS is also free !

Well I am not advocating any !! but since  John raised the matter of cost in his OP I'd have thought he could work his way through the freebies ( as I have offered !) first ?!

If we debate which is best we'll be here for a long time

1 hour ago, SilverAstro said:

Yes, GIMP 2.9.x will do 8bit, 16bit and 32bit, there are ready compiled portable (no installation needed) versions available for Windows,

2.9.5 portable for Win64 is here : https://www.partha.com/ (right-hand panel down the bottom)

I am Win32 and have 2.9.3 portable, but I dont have the download link to hand at the moment, I'll have to do some digging if you want it for Win32

Still not found where I got the Win32 portable version of 2.9.3 but at this site :-

http://nightly.darkrefraction.com/gimp/

there are nightly builds for both Win32 and Win64, but they may be installable versions ??

Being the latest in the 2.9.x development they may have an as yet undiscovered bug, so  make regular interim backups of your work in progress in case of unexpected crashes !

52 minutes ago, ollypenrice said:

DBE in Pixinsight has no rival of which I'm aware.

IRIS maybe ? http://www.astrosurf.com/buil/us/iris/iris.htm

specifically  http://www.astrosurf.com/buil/iris/tutorial4/doc14_us.htm

I dont have PI so I cant say*  but the method that I have seen described for PI looks very similar

* I'm not picking a fight / arguing !! just for info for John OP, who was looking for alternatives to PI

The rest of IRIS may be suitable for anyone who has mastered the learning curve of GIMP and is looking for more, err, excitement

3 hours ago, JohnSadlerAstro said:

Also, is there actually a 16-bit version of GIMP available?

Yes, GIMP 2.9.x will do 8bit, 16bit and 32bit, there are ready compiled portable (no installation needed) versions available for Windows,

2.9.5 portable for Win64 is here : https://www.partha.com/ (right-hand panel down the bottom)

I am Win32 and have 2.9.3 portable, but I dont have the download link to hand at the moment, I'll have to do some digging if you want it for Win32

23 minutes ago, Sp4rkR4t said:

I'd say use this thread to build your tutorial as you have done and then when it's finished copy the completed tut to a new thread.

Or we can do it ourselves ! I have just saved Part 1 (alone without all the other posts) to my Astro folder on a stick    thanks Gina

PS my tutorial on how to save just the contents of one post out of a topic could be an 'on request' a.n.other

Ah I see, so I dont need to download a big asteroid data base then. Well it kept me out of mischief for a wee while !

Beautiful detail you have in it, very well done.

3 hours ago, Nigel G said:

First is unmodded 1300d about 2 months ago, second is modded 1200d last night.

Amazing images Nige, gobsmacked even -to use the vernacular !

Quite a surprising(?) bit of red Ha in the unmodded 1300,  wonder what an unmodded 1200 would have found, wonder if Canon have changed filter passbands meantime !

So, cloudy and cold outside, I amused myself by having a fiddle with your images to make a blink and noticed a bit of activity as well :- some movements near my red, yellow and green arrows. I have not got perfect alignment but good enough I think to show the errr ahem curious ufos , well I have not identified them !

I third it all gone quiet outside, festivities over, musing on sgl with a glass of amber nectar and got to thinking -

is anyone using a GoTo dob ? I think most of you have alt-az on tripods ( Discovery, Evo etc) ? Are the dobs not up to it (too weighty to be moved smooth maybe) ?

HNYetc

6 hours ago, alacant said:

?

5 hours ago, Nigel G said:

I didn't get one with my mount,  I bought a dovetail bar and made a small L bracket,  having the 300mm bar will allow more chance to balance by adding some counter weight behind the mount clamp. 

6 hours ago, happy-kat said:

This comes with the Star Discovery and Virtuoso mounts.

link here

(edit it might not be in the box with the Star Discovery mount)

5 hours ago, happy-kat said:

I didn't realise the Star Discovery didn't have one of those in the box, I thought it did my mistake.

Not sure if I got all my quotes in the right order but :-

Hi, some months ago I was interested in the Star Discovery and was confused by this L bracket  as well !
I eventually discovered (I think!) that there are two versions offered by SW, a Track Bundle and a GoTo Bundle, but the former not widely distributed.
If you go to the pdf manual ( eg. on FLO : https://www.firstlightoptics.com/user/manuals/Star_Discovery_Manual_SL26032014_V1.pdf )

In there is , I quote,
"Star Discovery SD-Track bundle" and "Star Discovery SD-GoTo bundle"
"When unpacking the mount box, depending on your controller model , you will find the
following parts enclosed:" etc
/quote

the L bracket is only mentioned (included?)  in the Track bundle item A3 in the pic in the pdf. Not in "the SynScan version 4" bundle. The two controllers offered in the two bundles are quite different.

I think perhaps the track bundle is aimed at terrestrial tracking/panorama peeps and not astronomers, not sure - I gave up  !

35 minutes ago, SilverAstro said:

be interesting too to see what a stack of   20s  10s !

10 minutes ago, Stub Mandrel said:

Core doesn't look bad to me - there are stars in it, unlike mine!

Looks very good to me as well,  which may explain why I confused my 20's with my 10's !! anyway, yes it will be interesting to see the differences , ,  but anyway layer masks to make HDRs

52 minutes ago, Nigel G said:

 I think its worked, the 10s stack should tell.

150P Canon 1300D DSS & ST, touch up in PS express, Alt-Az goto.

Any ideas on core exposure welcome  

Worked very well indeed ! A very nice image. Would be interesting too to see what a stack of 20s would show of the outer regions.

There is a technique for using the shorter exp inner image (#1) as a mask over the longer exp image (#2) such that the dark areas in #1 become transparent and show/reveal #2 but the bright ( inner) areas of #1 are used (opaque) to mask out the overexposed bits of #2. I have only just started experimenting with it in Gimp, so not an expert and I cant advise how in ST, but PS I believe also has layer masks. A google on "layer mask" and "astro" should turn up something, and I'm sure an expert will be along here soon

2 minutes ago, Gina said:

Thanks for the suggestion but I have tried this before - unsuccessfully.

I guess ,,, the next pass wiped the teeth of the previous pass ? yes all sorts of hazzards await, a good supply of redundant/freebee disks is required it is a bit of a guestimate just how fractionally oversize the blank needs to be.

I'm sure you will overcome, as I said, just checking that you were not missing out on hours of fun

On 03/10/2016 at 19:20, Gina said:

very difficult to achieve in one go without using worm and worm gear and I haven't got the facilities to produce those.

Hi Gina, I'm a bit late on parade here ! dont want to teach eggs, just checking that you know of the ,makeshift ,amateur hob method using a tap - on slow in the lathe chuck and a disk on the top-slide/cross-slide that will become the worm-wheel ?? Depending on dia. of wheel then extensions, and live centre in tail-stock, may be needed whereupon it all becomes a bit iffy

just checking good luck.

1 hour ago, The Admiral said:

 It does rank as one of my better achievments though . And having been made aware of what my image contained, I was both surprised and pleased!

A very fine achievement indeed, we dont normally look this deep into images posted on SGL, a bit cruel even ! but actually if you blow up to pixel scale and measure the diameters they are not wildly different.

Anyway, V1 isnt there so I'll shut up about it in a minute ( I promise ! lol ) but one last comparison that shows how close you came : the stars marked 1 & 2 are very similar in magnitude to V1 and there is a suspicion that you got 1 perhaps 2, however they are similar to adjacent noise bumps marked in red, so not statistically significant ! More interesting though is that you deffo got number 3 and that is only slightly brighter than V1. So I think that you were just unlucky to not catch it at max when we might have been discussing a similar little bump ?

and there is a whole autumn and winter season at hand for you 

and it turns out we have amongst us a resident Delta Ceph archetype expert @Filroden ready to do the maths

4 hours ago, The Admiral said:

 those point-like stars from the 2.5m Newtonian! But then, there's a world of difference between a 2.5m Newtonian and an 'umble 102mm .

Quite so ! I did think last night that it sorta emphasized your 'blobs' and would you be unhappy, then decided that instead you would be pleased to be compared with a 2.5m professional jobbie and to be seeing with a 0.102m much of what it is showing  ! So yes, a jolly big pat on the back, and it has kept me off the streets and outa mischief as well

Yes, saw the AAVSO project, not had a chance to fully read it yet ( a lot going on domestically yesterday and it was 2am before I got back to posting those cluster magnitudes!) but I was a bit surprised that so few participated (when compared to how many variable observers of quite obscure variables there are in aavso and the bavso)

All the more reason to do an SGL version ??

9 hours ago, The Admiral said:

It would be interesting to know what magnitudes those globs were, just for reference, though.

I have not found a comprehensive list yet, but this site  http://www.astronomy-mall.com/Adventures.In.Deep.Space/gcm31.htm  has a list of the brightest 75 ( he gives a Bibliography, sadly nothing on-line though)  and of those I marked only these are in there.

G96 15.5 2.7"
G144 15.5 2.8"
G156 15.6 2.5"
G213 14.7 2.5"
G233 15.4 2.6"
G101 16.0 2.7"
G134 16.0 2.7"

less than mag 16 is quite respectable though   ?

6 hours ago, The Admiral said:

I've attached two TIFFs, the first a heavily cropped up-rezed image of the region in question, and one where I've just applied a heavy contrast enhancement using curves. Make of them what you will

Thanks, very interesting, yep I agree not there , yet , just a few more stacks or the right time ! You came very close, there is a negative pic from the 2.5m Newton on the AAVSO site, https://www.aavso.org/sites/default/files/images/m31_v1_int_r_0.jpg here is a blink of it reversed with your enhanced :-

3 hours ago, The Admiral said:

but leave no stone unturned!

Absolutely ! We often comment about the gear that is now available to the umble amateur and remarkable comparisons with images by famous astronomers ( and their institutions) of yesteryear. But wouldnt it be great if we could detect the expansion of the universe from our back yards with an AltAz,  that is what set me off on my quest , , , well actually it was your amazing pic wot done it really !

May your thingies always remain resolvable

PS Thinks, didnt note what magnitude those globs were , , , > >

On 03/10/2016 at 07:40, Filroden said:

Yes, I lived in Somerset until August. I moved North so my skies are very different.

Ah ! That explains it !! I used to use you and Gina's contemporaneous (sp?!) imaging reports/4casts as fair warning of me needing to be outside - - recently unreliable !! I dont recollect you asking permission to emigrate

The Hubble saga continues :

I did not know much about Hubble's Cepheid Variable apart from that he had found one (V1) in M31, thus was able to measure the distance  to M31  and demonstrate that the "nebulae" were in fact distant galaxies, leading eventually to the Hubble Constant.

Wouldnt it be fun if all that could be done with an AltAz I thort ? So off I went a'Googling ,  and many fuzzy drawings and pictures later I found this amateur (John Taylor)  site who has been after it as well :- http://cloudedout.squarespace.com/blog/2016/3/23/hubbles-cep

 I could not see any trace of it in Ian's pic and wondered if it was coincidentally not at max. however sadly it turns out that it is a measly mag18 at max a bit of a challenge !

Here is a blink of the location on Ian's pic with a snip from John Taylor's site :-

Edit : Oooops, I've removed the blink because (a) JT on his site says copyrighted and whilst I think it is ok to use snips like one would a quote I dont want to offend anyone ! and (b) Ian and I are both agreed that he has not (yet ) recorded V1 at the position JT has indicated.

Quite a remarkable agreement between the two views and you know, is it my fancy, or fortuitous pixel of noise, or maybe a suspicion of a V1 there ? ? Might need a few more efforts like that over the next few months Ian  

7 hours ago, The Admiral said:

It is true that clusters tend to be easier because you are not dealing with feint nebulosity and you can get away with a shorter total exposure, but there are many clusters and only one M31 .

Interesting that you should say that, there are indeed many globular clusters to be had, many of them are in M31 as well ! And within the range of No-Eq as your image has shown !! Wow

By coincidence, - when you posted your superb image of M31 I went looking for Hubble's Variable, more of that in a minute, and along the way I found these M31 Globulars :-

The numbers should all be prefixed with " G " and are the references used in Paul Hodge's "Atlas of the Andromeda Galaxy" :-  http://ned.ipac.caltech.edu/level5/ANDROMEDA_Atlas/frames.html , aided by Robert Gendler's excellent interpretation of it. :- http://robgendlerastropics.com/M31NMmosaicglobs.html

The above is just a wee sampling of loadsa them

22 minutes ago, Nigel G said:

In the meantime I bought the wife a new DSLR today with my scrap copper haul ( I'm a plumber by trade )  /  so I'm going to try her new camera. 

My wife approves, and she wants one as well

53 minutes ago, The Admiral said:

Thanks SA, but it was more trying to avoid messing about with laptops and all the wires rather than mono vs colour. That's what I like about dslr's, you have a single package that you attach to the scope and away you go.

Ah, I see, my mistake/missuners, sorry. There was  ofcourse that amateur astronomer who attached his whole observatory to the scope ! He used a shed with internal divider, the scope altitude axis passed through the eyepiece which then passed through the dividing wall and the whole contraption, including comfey seat in the warm half, was mounted on a car? lorry? wheel bearing for azimuth ! No-EQ eat yer heart out

4 minutes ago, Filroden said:

some of that blue could still be light pollution. I have three LED street lights around the garden and the town has LED in most streets so it will seep into all three channels.

Yes indeed, that is why I still needed to use some *mild gaussian filter on the green and blue to reduce the gradient in there as well, but most seemed to be in the red ? I was thinking that most of the remaining green/predominant blue in the lower bits showed structure ? therfor neb. ( dodgy asumption perhaps ) whereas the gradient ( on the basis of that in the red channel where it is easy to see) was a more even band ?

* It was touch and go though, not to remove neb., so I used a large radius, and only 60%, for the filters.

All good stuff whilst it is cloudy outside, thanks for something interesting to do

Good luck, will be interesting to see what else you pull out of the originals.