groberts

Thanks, just under twelve hours - for more detail refer to my website here: https://watchthisspaceman.wordpress.com/2021/11/16/the-journey/

Graham

Autumn has been something of a curate's egg for me, on the one hand I had a number of good sessions at the beginning of October that for a change produced some very good data, however soon after I had a complete melt down of my main computer and am only just getting back on my feet - computer and processing wise!  Still, very happy with this version of Andromeda which comes from that period, at last (after more than 5-years) I think (hope) I'm getting to grips with this magnificent object and will no doubt be back another day to try again.

Graham 

Many thanks guys, pity it looks like more costs but I guess that's inevitable. 

Have watched videos on both and, of course, they do a very similar thing.  Would be interested in the first hand experience of any others who use either of these or alternative techniques before I proceed.

Graham  

OK thanks  Alan but what is a Spider, what does it do, how does it do it + where  do I get them? 

Graham

Following the complete meltdown of my main / processing laptop I've just acquired a replacement running Windows 11 and am struggling to get the 'correct' colours for images. 

I've been using the Windows' Colour Calibration process accessed via the Control Panel to adjust Gamma, Brightness, Contrast and the one that's causing me a headache which is the adjustment of Red-Green-Blue levels to achive a neutral outcome.  At first the result doesn't look too bad after tweaking these colour levels a few times but when I look at terrestrial photos I can't seem to get rid of residual green and / or yellow hues that seem to linger.  Looking at my astrohotography images, which I was hitherto happy with they look all over the place, especially the sky colour which I'd processed to something that previously looked OK with a decent black point (and still does on another back-up laptop) but not on the new laptop.  

I would appreciate any guidance on how to deal with this issue i.e. colour calibration on a computer not each image, preferably not too complicated and / or is there a better / foolproof technique or software available that might help?

Graham       

I've been using a Toshiba  P70-B-10T Intel i7 laptop for day-to-day use in my study, which also means it's my main computer for image processing using the usual PixInsight + PS etc.   Last Friday it stopped booting up and after looking at it over the weekend my computer man (who has saved me from such problems many times before) now thinks it may be the Graphics Card (AMD Radeon R9 M265x 4GB) and cannot be replaced i.e. time to look for a new computer!

Before I start trawling the internet I thought I'd ask here if anywone could point me towards something suitable - laptop or PC (mini?) running Microsift Windows i.e. not a Mac.  As I now do more and more image processing using PixInsight, PS, Topaz AI Denoise etc the size of the image files has grown so it needs to be something with the capability to handle this + decent screen >=17" LED backlit or similar, +/- 16GB RAM, +/-2Tb SSD disc, +/- 4 ports USB 3.0 & 2.0, + a higher spec Graphics Card that can handle the current version of Topaz AI Denoise etc. -

It doesn't have to be a laptop but because of space not too big a PC i.e. probably rules out full size tower.

Any recommendations / thoughts much appreciated.

Graham 

After a prolonged break over the summer - extended by laying a new patio on which my mount stands & at the same time discovering a well, which became a project - I'm back on the horse and this is my first image.  As ever, subject to some more  adjustments + calibration at the 'new' location is required but this is a promising start 🤞    

For more image information please see my website here: https://watchthisspaceman.wordpress.com/2021/09/12/the-well-the-butterfly/

Graham 

Superb image - your hard work has been well worth it 👍

After months of cloud and thus partly motivated by desperation, I managed to grab some limited imaging time over x4 nights of IC443 the Jellyfish at the end of March / early April before it disppeared over the western horizon for another year.  Notwithstanding the problems, I'm pleased with the resulting HOO image (+ Ha false luminance and RGB stars) and will be hoping to convert this to an SHO image at some later date.

Whilst IC443 is obviously the star of the show, the significant nebulosity behind it plays an important role in the image but I'm unable to find anything written about it - would be interested in any advice / comments on this feature?

Graham

AZ-EQ GT mount + William Optics GT81 & 0.80 focal reducer + ZWO ASI1600MM-Cool + 31mm Chroma filters etc.

Processing: DSS + PixInsight + Photoshop + Starnet + Topaz AI Denoise

Total integration 6hrs 02min:

Ha x15 & OIII x12 @ 600secs

L x11 + R x11 + G x9 + B x11 @ 120 secs

Thanks Lee, the combination worked well with the aperture.

Graham 

From earlier in the month + probably my last image before summer nights descend upon us; I do so like globular clusters!

For imaging info + alternative framing see my website here:   https://watchthisspaceman.wordpress.com/2021/04/28/twos-company-3/

Graham

At last with some clear skies and a new moon got to try out my new 31mm Chroma LRGB filters on Markarian's Chain (bought last October!) + very happy with the outcome.

AZ-EQ6 GT + WO GT81 + ZWOASI1600mm-Cool

• L 120x60"
• R 55x60"
• G 55x60"
• B 55x60"

Total integration 6hr 45min

Graham        

Thanks, I'm imaging in Surrey at the moment and that explains why the seeing is not what I was expecting 😠  

5 hours ago, Pixies said:

Yep, forget the seeing conditions tonight:

As a matter of interest what is the source of that map please?

Graham 

Thanks vlaiv, seemed obvious but just thought I'd check.

Graham 

I routinely image with a CMOS camera (ZWO ASI1600mm-Cool) and calibrate with darks, flats and bias -  recently switching to Dark Flats instead following various online advice. 

I now have some CCD data to process - having never processed CCD data I presume it's essentially the same but should I use bias or dark flats, or even both (which would seem unlikely)?

Graham       

In consideration of purchasing the new ZWO ASO294mm Pro camera I've been reading posts on various sites and there's frequent emphasis on the importance of ensuring that the native driver is used.  What exactly is a native driver + would also be interested in first-hand experience of those using this camera with APT?

Graham   

Thanks - I've used bias with my ZWO ASI1600MM-Cool for over 4-years with no apparent probelms but with new filters + weight of advice in favour or using dark flats I thought I'd give it a try. 

Just completed my fist image here and all looks good, though whether bias would also have been OK I'll never know.  It's just that bias was easier and quicker, though with the APT Flats Aid function the extra effort required is limited.

Graham     

Thanks all much appreciated.

My problem with much longer exposures is (a) light pollution (b) aeroplanes (when they're flying) and (c) polar alignment and its impact on set-up + guiding etc. as I cannot see Polaris - my house is in the way!  

Can't do anything about light pollution except move = watch this space, make the most of the current lack of flights (I live between Gatwick - Heathrow airports + Redhill aerodrome down the road - of course I didn't do astronomy when I moved here!) Using PHD2 polar align routine + with the new multi-star guiding choice my guiding error is at last now looking very good.  The 10-minute exposures this time worked out well + it cuts down data use, though still unsure about how to use the LRGB filters i.e. exposure times .  

I think more experimenting will help but overall the new filters are good. 

Graham           

You can blame me: I purchased a set of Chroma filters last October and have been unable to image ever since due to the weather! At last in late February / early March I managed a few hours albeit at full moon, so for my 'first light' experience of these filters went narrowband.  Whilst I'm happy with the attached Rosette image - certainly the 3nm SHO filters have improved the stars when compared with my previous ZWO filters - there were a few things:

• For the first time I went to 10 minute exposures as, I presume, the 3nm filters seemed to 'need' more light?
• I also did a quicky and dirty LRGB of M42 (not yet processed) to try out the other filters and was surprised to find the Luminance very overexposed at 180 seconds compared with the ZWO luminance filter using the same exposure & Unity settings.

I would be interested to hear from others who use Chroma filters and their experience and thoughts on how to get the best from them e.g. I've always used the ZWO ASI1600MM Cool camera + ZWO filters at unity with good results but maybe the Chroma would benefit from higher gain etc.?

Graham

9 hours ago, Cobberwebb said:

Just done my 2 best images with a SA now that I have a car and can get to a Bortle 3 site. Had the SA since October, but only recently been able to use it properly due to work and weather.

No guiding.
Lights and flats only.
Nikon Z50 (not astro-modded), 50-250mm F4.5-6.3 kit lens
90second exposures @ ISO1600

M31, 36 light frames.

Great images @Cobberwebb  well done.  I'm interested in a lightweight set-up like this and wondered:

1. What tripod are you using?  I have a Manfrotto 190 and would like to know if this is good enough to take the Star Aventurer?
2. How + why are you using the mobile phone in the picture with the set-up?
3. Your not guiding but presumably stacking the said 31 frames - what software have you used?   

Graham

I've been imaging for some time with a CMOS ZWO ASI1600MM Cool camera and have been mostly happy with the results.  For calibration I've been using Darks + Bias + Flats registered and stacked in DSS but a while ago saw on SGL and elsewhere comments that with a CMOS camera it's better to use Dark Flats - better than what and why?  I've therefore for the first time taken some dark flats (using previously calculated flats @ speeds for each filter but with the telescope cover on i.e. dark - right?).  The questions I now have are:

1. Is it good to use dark flats with CMOS cameras?
2. How do I use the dark flats in the registering and stacking process? 
3. Do I just add them in together with the darks + bias + flats or do they replace one of these, bias perhaps?
4. Any other guidance?

Graham 

After months of cloud we have clear skies & a full Moon!  Notwithstanding, I have at last started to try out my new Chroma filters which I bought last year.  Because of the Moon I've concentrated on narrowband but focus manually using a bahtinov mask (as I've always done previously with ZWO filters) with the Luminance filter - frankly I can barely see anything with NB filters to focus; in an ideal world I'd refocus with each filter. 

Anyhow attached are 6 x 10 min Ha 3nm exposures from last night and I wondered if this looks OK, not entirely sure what to expect?  I use a cooled ZWO1600MM + WO GT81 and this image is without any calibration + RMS guiding error of +/- 1.10 + quick stretch i.e. not finessed. 

Whilst I appreciate longer exposures are always better, I would usually image at max 5-minutes or less because of numerous planes and helicopters - I live by Gatwick airport (not a problem at the moment) and my guiding though OK is never great as I have no sight of Polaris - my house is in the way.

I would apprecate any thoughts or advice using these filters + aforesaid comment on this trial image.

Graham   

That looks really good on the wall Brendan, would be interesting to know the imaging details 

I can see some of you are sucessfully using this lens with the Star Adventurer mount:

• How do you find this combination - with a DSLR, OSC or Mono camera?
• Would like to see pictures of the set-up if possible please?
• How does the mount handle the weight?
• I see the mount can go with a decent photography mount, I have  manfrotto 190 - would this be up to the job?

Where I'm going with this this to try and establish light weight set-up with the Samyang.  I've been using mine with the AZ-EQ GT which is great but something more portable appeals.

Graham