Notty

On 21/01/2021 at 12:51, Scooot said:

Hi Andrew, how did this work out in the end?

I’m interested in a similar setup.

Hi Richard, apologies for taking so long to reply to this. It works better than I had hoped, there is (on my example of the lens anyway) more than enough back focus past infinity that the autofocus works like a dream through the ASIair. I'm really happy with it.

insanely beautiful...

For completeness, here it is now with Ivo's fantastic trick for de-purpling the stars, with extra Ha data & OIII from last night. Much happier with the colours now. Total integration time therefore 15hrs: Ha: 4h SII 4h OIII 7h.  Calling it done.

See you all in another year when time/weather align. Thanks for looking and clear skies all.

23 hours ago, emyliano2000 said:

Happy with how it looks.  A lot of people might not like it but I added some artificial star spikes (I just love star spikes and I think that if you do it carefully, they look very real )

I’m with you and I miss my reflector for that reason only, but I didn’t know you could add diff spikes that’s awesome! Mind telling me how you do it?

12 hours ago, jager945 said:

Congrats on a fine first SHO image!

Purple stars are extremely common due to the low emissions in the Ha band of stars. Some people find the purple objectionable (I can personally take them or leave them ).

If you are one of those people though, there is a simple trick in ST to get rid of the purple;

With Tracking off, launch the Layer module. For Layer mode, choose 'Invert foreground'. Notice how the inverted image now shows those purple stars in green. The Color module has a Cap Green function. Set this to 100%. Launch the Layer module again, once again choosing 'Invert foreground' for the Layer mode. This flips the image back to normal, though this time, without purple stars,

I believe this trick/hack should also work in PixInsight with SCNR.

Thanks for the feedback Ivo! I’m going to try that trick when I’m home on a couple of days, I definitely prefer my stars less purple. Startools continues to amaze me with its capabilities- so thanks again.

andy 

Due busy life I don't produce much, and when I do it's rarely that great. I know this is still noisy as hell but it's the first time I've persevered over multiple nights trying to acquire proper data, and for the first time I've come up with something I really like, and the crop of the core is the nearest I think I've come to a "proper" astro image . I'm definitely needing more OIII as that seemed to be the weakest of my 3 channels, and some more Ha as L might help the noise some. Lots of data thrown away and ended up with 2.5h Ha, 4.5 OIII 4.5 SII. Processed in Startools.

Hopefully a combination of vastly reduced working (not good!) and ASIair (v.good!) is going to give me more opportunity going forward. Comments and criticism very welcome. Thanks for looking

ASI1600mm+Samyang 135mm

On 01/08/2020 at 09:46, bottletopburly said:

@Notty this may be what you want 

https://deepskydad.com/laf

Thanks for that, it looks nice especially the mounting arrangement. I went for this setup; astrojolo supplied mounting rings and guidescope mount plus a toothed pulley/belt arrangement inspired by another user on here. I haven’t connected it all up to try it yet, I fear autofocus won’t work as I’m told there won’t be enough back focus  behind infinity to automate it but at least I should be able to control the motor focuser through asiair without touching it, which should still be more precise.
 

17 hours ago, knobby said:

https://www.ebay.co.uk/itm/303607598518

Ah ok, thank for that. I already have that setup but want to automate it. I'll be doing lrbg+narrowband and want to make it as precise as possible.

7 hours ago, Tomatobro said:

Take a look at this as a possible alternative Ebay

303607598518

 

Hello, thanks but I can’t search this on eBay - thinks I’m looking for a userid?

Hello. As title, has anyone had any luck setting up the above? I have a Samsung 135mm which I’ll be using with my 1600mm and controlled by ASIair. If anyone’s found an off the shelf transmision/belt drive solution or gone through the pain of assembling one would you mind sharing the details at all? Thank you in advance.

andrew

On 03/07/2020 at 21:48, Simon P said:

I am looking at the  same sort of set up to start deep sky and am trying to decide between the 100 which is an f5.5 and the 120 at f7, eventually I would hope to get a zwo1600.

 Any advice would be appreciated.

I was interested to see the problem with availability.

and here comes a possible trade war with China, so Sept/Oct might be optimistic!

23 hours ago, gorann said:

I have two Esprits, 100 and 150 and I love them, so I am sure the 120 would be an excellent scope. However, an alternative from which I have seen great images is the 130 from TS. You can see on Astrobin what "pete xl" https://www.astrobin.com/users/pete_xl/ can do with it, very impressive, and it comes at a very reasonable price. There are two versions that only differ with regard to the size of the focuser (according to TS - I asked them since I am tempted to get one myself):

https://www.teleskop-express.de/shop/product_info.php/info/p6679_TS-Optics-PHOTOLINE-130-mm-f-7-FPL53-Triplet-APO-Refractor.html

https://www.teleskop-express.de/shop/product_info.php/info/p7717_TS-Optics-PHOTOLINE-130-mm-f-7-FPL53-Triplet-Apo---3-7--Focuser.html

and the one with the smaller focuser is in stock and in my experience TS do not lie about this but you should ask them.

If you google this scope you find some good info, especially on Cloudy Nights

 

Wow, that chap knows what he's doing, and has same camera as me too. definitely worth a look, thank you and everyone else who's chipped in.

Thanks all. I hadn't heard of Raig or Harpers, but they're quite significantly more expensive than everywhere else I've checked, and its the same story, they can't make them fast enough for demand!

5 minutes ago, scitmon said:

How about a StellaMira 104?  or is that aperture too small?

Yes, really I want a bigger step up from my ED80 for galaxy resolution - if I could afford the 150 triplet I would! but thank you

17 minutes ago, PeterCPC said:

Rother Valley Optics have a Esprit 120 in stock according to their website. But check.

Peter

Thanks, but they don't I checked yesterday. In fact while I was on the phone confirming they had the last EQ6R-pro in the country in stock, someone bought it. It's that mad at the moment

After 8y or so building up my ED80/HEQ5 based imaging rig I have just sold it in order to go "big bang" on upgrading it, (scope, mount, ASIair) hopefully with one good enough that I will always be the limiting factor for the rest of my AP days.  I'd done my research and had decided the Esprit 120ED on an EQ6R-pro would suit my purposes with my ASI1600MM, but what I hadn't appreciated was quite how little of anything there was in the UK and how it's literally drip feeding in from China. The wait for the Esprit is October! Now I don't mind waiting and missing out all summer for the right kit but it's given me pause to just run this by to see if there might not be a better choice of scope for a similar price range. I'd love a Tak but that's always going to be out of my league, or perhaps someone's heard of something gorgeous just around the corner? Thanks for any input.

5 hours ago, jgs001 said:

Notty, it's 67.5 mm... The f number is the focal ratio, and is the relation between the focal length and the aperture. Divide the focal length by the f number to determine the aperture at any given f number... so if f/2 is the largest aperture (as it's a ratio, smaller number = larger hole) then 135/2 = 67.5

Thanks, yes indeed, I was just thrown by where the 77mm came from, or if perhaps quoted F ratios were rounded up or some such.  Really glad I found this thread still, thanks all.

8 minutes ago, PeterCPC said:

? Using my Samyang 135 F2. I have been inputting FL 135mm aperture 77mm.

Peter

I was looking for max aperture size on the Samyang tech pages but didn't see anything, they mention 77mm as "filter size" but would that not make its focal ratio 1.75?

8 minutes ago, PeterCPC said:

No. Use Custom Scope then input the lens focal length and aperture.

Peter

Thank you - aperture being presumably exactly 135/2 for F2 

On 21/04/2020 at 08:37, Craney said:

http://www.blackwaterskies.co.uk/imaging-toolbox/

Put your telescope as  a  200mm F5   (   200x5 =1000mm FL).    Program does FOV and so aperture is not important in the final result.

Then set your  Barlow /Reducer option  to whatever fraction you want. 

So  135mm will be    '0.135'   x 's   reducer.    300mmm will be 0.3x

 

So glad I found this thread, sorry to hijack and jump in, but for a 135mm F2 camera lens, do I need to find an equivalent F2 telescope (do they even exist)? Or am I missing something?

That is stunning. Such a shame I can't get this target where I am this time of year, otherwise this would have inspired me to have a try myself.

That is gorgeous.

2 hours of Luminance, 40 mins each of RGB, dithered in PHD best 95% stacked with darks, flats and dark flats, ASI1600m ED80-DS processed in Star Tools. Now the thing with this is I started my guiding and it was just awful, although to be fair it warned me calibration was too far off the CE to be reliable but I did it anyway just to start harvesting. I was getting about 1.1rms, so I wondered if I binned everything 2x2 it would help, though I'm still trying to get my hear around the science.  I wonder sas this is a valid approach under crappy guiding/seeeing? I think it means I end up with a effectively very expensive DSLR haha! I'm quite pleased with the image for my standards anyway. I put the slightly cropped one up as well. Thanks for looking.

Why thank you everybody for the tips and info I’d not thought so much in terms of arc seconds/pixel. I’ll have a look at the Altair 102 as well.

I shall have a look at that, thank you.