GalaxyGael

Comet C/2021 A1 (Leonard) captured over 10 mins (5 x 120 s) on Dec 5th, 2021. In this image, it is drifting through Boötes in front of NGC 5523, NGC 5498 and another distant spiral galaxy NGC 5008.

Very nice Richard. Good use of our minuscule weather windows. Love the dynamic range in true color with no posterization of the core region. Do you find much of a difference between gain 0 and gain 100 in the individual subs or in the overall stack? Curious to know from your experience if high sub numbers counter slightly higher noise at gain 0 for any target, only only the brighter ones. Fingers crossed for a few clear hours over the weekend maybe.

Lovely image Lee. That object is big on the sky, delicate looking.

1 hour ago, GavStar said:

So existing 166mm tube rings will no longer fit or have bigger gaps?

Might depend on the ring construction. I bought the hexagonal rings designed by Teleskop austria to fit the 130D (its 166 mm diam. variant. I did not know the 130D had been updated at all, but since these rings come apart (screwed together at both side, without any hinge), it was an easy fit with (I guess) a slightly large gap between the connection points. Images in OP show it. They will work perfectly. not sure how some hinged designed might fare though.

10 hours ago, Highburymark said:

Suspect it may just be cosmetic - just like the new blue Tak refractor colour a couple of years ago. The Epsilons do seem to have very long lifetimes between model upgrades. The good news is they hold collimation incredibly well. I haven’t adjusted mine since I bought it - and that was secondhand.

It might be just that, but I notice the focuser is closer to the front in this model, no gap between the front ring and the focuser. Mine also looks well collimated, and certainly the primary mirror ring is centered. A very slight asymmetry in the reflective ring from the tak cheshire, but there is a tiny shift in the visual adapter that could explain it. I wont tweak until I get first light, but using a well collimated laser with a screwed m48 connection to the focuser shows the beam hitting the secondary mark exactly and almost perfect int he center of the donut. The engineering of the primary and secondary are surprising in the flesh, ultra stable construction. I had heard about this sability, i can understand it now. I am unable to unscrews the secondary collimation screws they are on so rigidly fixed! The OTA diameter is slightly larger at 170 mm, same length at 460 mm.

Cannot see anything obvious that has changed, secondary and primary cell and their collimation screws look identical at cursory glance. Maybe the collimation stability during focuser rotation has been improved? We'll see in due course

With in situ calculated color-colot plots in APP, you have control over the color calibration. Useful when no connection available to do photometric cc using a database, but leaves the result to users choice of stars and that needs to be carefully done, especially in full moon BB data where blues are not the same as new moon imaging.

With a good fit to the color-color plots in star color calibration ( correct balance in blackbody modelling of main sequence stars that are mostly yellow to red) and fitting of the slope trend lines, the amount of golden hue you normally see here, m101, fireworks galaxy, and others, can be altered with choice of the magenta-green sliders in APP color calibration. 

To check if full moon imaging affected color, you could run photometric cc from databases using PI or siril to see if the data is has some color issue, or if it is just the APP fitting/settings.

You can also downsample bin in APP during integration. Mitchel-Netravali rather than Lanczos-3 is good for this.

No. Once the retaining ring was screwed back and the distance optimized with the grub screws to avoid downward pressure on the mirror, I added the printed ring aperture mask on top of the retaining ring, i.e. added on top of the fully assembled mirror cell. It masked the edge of everything essentially.

 Not many images in the wild of the Tak Epsilon 130D after what I discovered this morning. I had intended to get the 130D over the 160ED, in order to get the 1.5x extender too. Kid in a candy shop feeling this morning for an hour !, but first thing I noticed was the new colorway, identical to the updated 160ED. Since they are collimated and sealed, not so obvious for any vendor to confirm and no images clearly showing it online, even on Tak's website. Here's what it looks like, the small mods are the same as found on the 160ED.  Might post on the scope etc. when I use it later in the spring.

Are you referring to a vertical 5mmm gap away from the retaining ring? If so, that should be OK. Mine is separated vertically by roughly that amount as i used a double side padding normally used for putting towel hangers onto tiles in bathrooms - very sturdy, doesnt contract or expand and resistant to moisture/vapor. 

I find this too sometimes, to the point where I don't remove stars anymore in OSC images. Given your data set is very good quality, I'll bet processing with just light star masking might come out better and keep the stars blended in the image. when I use star removal, even when it appears to work well, it has the NB image effect (that's what i call it) where the stars always look 'added' to the image, if that makes sense. Great M101 btw, head start on galaxy season!

Lovely image and resolution. Regarding stars, curious to know if you have processed it without removing stars at all, especially if the black halo ringing artefacts come from processing during decon or star removal/reinsertion?

Edit: Asking about availability, as the 160Ed extender was announced last year.

Does anyone know if or when the 160ED 1.5x extender will be announced for this scope? Two hefty beauts were released for the 130D and 180ED, mention of one for the new 160ED but no sightings in the wild.

Asking for a friend.

On 17/01/2022 at 08:53, geeklee said:

This is a great addition to a typical narrowband target.  Very nice image and well worth the integration.  Lovely starfield.

Thanks. Fewer OSC or LRGB versions of this than I expected, and somewhat clear why its a nice NB target. The stars and the background play a bigger role in broadband to me, although I'll reprocess this in my normal way someday without the starless+stars combination I did here.

Recent image testing a longer focal length refractor for the first time.

1 hour ago, lock042 said:

Did you tried to remove background on each sub? It works pretty well.

 

Siril works only with monochrome or CFA flats. 

Yes, but it is inferior to APP with my gradients, which shift during imaging and between night (neighbours lights etc.). It works very well with cleaner data sets though, I like it overall. 

I always get an error when using monochrome masterflats, never works. These flats were recorded mono using osc camera. 

I think Siril is great overall, but the background removal takes several tries for those in severe light poll. gradients like me, I find. APP still is the most effective imo in that regard. 

But, does anyone know how to use monochrome flats in siril? Even master flats from APP show up as single channel and siril seems to do e everything(?) based on channels? I would likely use it more was it not for issues with monochrome flats or master flats (color) stacked elsewhere where itcomplains that it does t ha e required channels to work with lights. Especially for older data where I cannot get new flats for example.

Scripts are handy, but the photometry parts are quite nice and still amazes that it is freeware too. 

Know of someone in the US who had 144 nights of imaging in 2021!! Those are the one they decided to image on... Silver linings though, we the ' haul it all out each night' brigade would be in traction by then 😛. Wonder what must planning a 30 hour imaging run feel like when the worry is not the weather... 

A really well corrected triplet with in built flattener, 103mm aperture at 825 mm focal length is the vixen ax103s. Superb flat field and can be reduced to 635 mmat f/6.16 of you want. 

Nice image John. The idea of a clear sky star party sounds great. Sounds like a good location. Actually, a party right now would do 😀. 

Scope staying stable during all the travels? 

Cs

This is M45 imaged over a few shortish sessions on 4 nights recently where we had that miraculous gap in the low thick cloud cover that seems to have taken a shine to Cork city. The tweaks to the Hypergraph 6 summarized here seem to be working and it is a joy to use now. Holds collimation very well, haven't touch it in weeks. 

This was 283 x 120 s subs with the Hypergraph 6 using the ASI2600Mc Pro at -10C with Gain 100.

No filters.  Bortle 6 (SQM 19.96). 120 of the subs were under 98% moon, but seemed just fine to me. It was about 20 degrees away in the sky.

Guided with ZWO OAG on an iOptron GEM45.

Processed in Astropixel Processor and PS (CS5). 

The tilt adapters Goran suggested might be the best option if they fit, and keeps your 2600 at least formally tilt free for any other use and for trouble shooting down the line. Based on your pictures, that base looks to be the source. tilt offsetting the 2600 would work if when you screw it on, one of the tilt screw is juts at the right place making the adjustment straightforward. Otherwise you might have a three-legged stool problem trying to raise the tilt plate in one particular place using three screws in different orientations.

An alternative and permanent workaround could be a very small 1-2 mm optically thick adapter with a sanded side that screws onto and compensates the higher side of the baseplate, onto which everything else is screwed. Not ideal of course. What I did with a Vixen VC200L with a similar tilt problem from a mal-threaded focuser attachment was to glue a thin metal shim to compensate. I used a segment of an aluminium 0.3 mm space ring to do that. 

1 hour ago, Marvin Jenkins said:

So do I. I have always thought those prominent bright stars should look exactly that.

M 

Interesting isnt it. I was surprised when I saw it. I'm imaging M45 at the moment, and gathering a lot of subs here and there. I wonder will they also stack with this effect. 

1 hour ago, tomato said:

That’s a really nice image, your OSC setup has captured both great colour and detail.

Thanks. The color did come through even though the moon was a lightbulb and shooting through a few air masses, but its a nice target even at 420 mm and ~1.85"/px.

NGC 3184 (Little Pinwheel) and μ UMa imaged last week.

190 x 120 s exposures with the Hypergraph 6 on the iOptron GEM45.

ASI2600 MC at -10C, Gain 100.

78% moon, but silver linings - I could see the USB port on the mount rather than feeling for it!

Captured with Sharpcap 4 sequencer and processed with APP and PS (CS 5)

μ UMa came out with the 'classic' ring flare, and I really like it.