Aramcheck

Whichever scope you decide on, I'd get (or make) a Bahtinov mask to help with focusing. The Astro Photography Tool (APT) software is also very handy.

Cheers
Ivor

If it's like the Skywatcher EQ130, there should be a lever which acts as a clutch. Lift it up to disengage the motor gear.

I had a quick go with the data, but with a rough quick process I got this odd grid pattern... Any idea what's causing that?

Cheers
Ivor

I prefer the right angled finderscope, which also has the advantage of the image not being upside down. Looks like Seben do one:-
https://www.amazon.co.uk/Seben-Right-Angled-Telescope-crosshairs-bracket/dp/B00HUOFDQ0

Cheers
Ivor

20 hours ago, Somerled7 said:

Looks better than mine (no surprise there!!).  I have a 200P that I use for visual observing so I could try that for imaging, but I am guessing that would be too much scope for my HEQ5 mount.  

@Somerled7 I thought your image was pretty fantastic - especially for a first shot! In your other post you mentioned difficulty focusing with the 200dps. It's worth getting (or making) a Bahtinov mask to help with this. Also have a look at Astro Photography Tool. It's much easier being able to see the camera live view / images when their on a laptop screen & it has a nifty Bahtinov Aid tool that helps you fine tune the focus.

Cheers
Ivor

I've just found the Aladin sky atlas:- https://aladin.u-strasbg.fr/aladin.gml

This identifies the small galaxy as "MCG+09-23-025" a Type 2 Seyfert- http://simbad.u-strasbg.fr/simbad/sim-id?Ident=MCG%2B09-23-025&

Cheers
Ivor

Like @Somerled7 I had M101 in might sights last Wednesday night / Thursday morning... My first go at dithering in between subs, using PHD2+APT, which I estimate added about 38 secs to each 180sec exposure. Managed to get 55 x 3min subs, between 22:38 and 03:01, when the birds had started singing. The SNR in the last 8 looked too dodgy, so here's the result of the remaining 47 stacked.

Does anybody know a way to find out what the small galaxy is in the top left hand side, near HD122601? (I've already tried http://nova.astrometry.net/)

SW200dps+EQ6, Canon 600D (astromodified) + IDAS D2 filter & processed in Pixinsight - found that I didn't apply TGV De-Noise on the last image properly... Processing a little rough on this one also, as mostly on auto-pilot from lack of sleep!

Glad I managed to get the dwarf galaxy NGC5474 in the frame as well - it presumably has been affected gravitationally by M101 in the past, so that the central bulge is offset.

Cheers
Ivor

On my PC the gradient doesn't isn't as noticeable from within Pixinsight, but following @wimvb's advice I redid DBE on the v2 image and that has helped a great deal.

Cheers
Ivor

When you open a colour RAW file in Pixinsight, the Process Console says what Bayer pattern it is under "CFA pattern". (On my Canon it's "GBRG". )

Then when you run the Debayer process you should select the appropriate Bayer/mosaic pattern to match that from the camera file.

Cheers
Ivor

From last Wednesday night... 51 x 180sec subs. SW200dps + EQ6 + Cannon 600D (astromodified) & IDAS D2 light pollution filter... Bortle 6 skies. Second night guiding & haven't got dithering working yet...

Thanks to @wimvb & @discardedastro for the tips on processing in Pixinsight!

Cheers
Ivor

@wimvb, @discardedastro - Thanks both. I've gone back to the non-drizzle stack, reset defaults and that now seems to be working ok...

I'll see how I get on now!

Many thanks

Ivor

37 minutes ago, wimvb said:

This is what I got with default settings of PCC, with fl 1000 pixel size 4.3 and a background preview as background reference.

Arcsinh stretch and lifting the outer regions of the galaxy a bit. I see now that I boosted the colour in those regions a bit too much.

Processed in PixInsight 1.8.5

Btw, I would have framed the image a bit different to keep that small galaxy at the bottom in the frame.

@wimvb Thanks - excellent, although I'm perplexed why my defaults are just giving a white image... Could you post a screen grab of the defaults?

In hindsight - yes, I should definitely have given the scope a nudge to bring that smaller galaxy into the frame. I had expected that I would need to crop the image so didn't bother.

Thanks!
Ivor

1 hour ago, wimvb said:

I found a fl of 1010 mm, not the 2000 of the original post.

That's because the original screen grab is from a drizzled integration & doubling the focal length is necessary in order for the PCC to match stars. On the non drizzled stack I use 1000mm for focal length.

1 hour ago, discardedastro said:

Interesting - i think there's some issues with pattern noise which might be throwing off the automatic stuff. Just doing PCC (all default settings, using metadata from image) and then whacking colour sat up 3x...

You can also see lots of spread in the PCC charts - this isn't good, you should usually see a pretty tightly grouped set of points. There's not much in it in intensity between the fainter nebulosity and the background. How many frames stacked was this? Are you dithering the scope during guiding?

@discardedastro Thanks - could you possibly share a screen grab of the PCC settings. I thought I had already used the defaults, but you've got a much better result!

It was 51 x 180 sec subs & 2nd night guiding. I haven't figured out what settings to use for dithering yet...

Cheers
Ivor

2 hours ago, Anne S said:

Have you tried applying stf again? That should adjust it.

Yes - first thing I did...

Cheers
Ivor

1 hour ago, wimvb said:

What are your background levels? You may need to increase the allowed level.

Alternatively, load up the tif here (non drizzled or it will be too large, or just a preview of the original) so we can have a look.

RGB levels are 0.01 or below which is comparable to another image I took two days earlier, but with 60 sec rather than 180 sec subs. That earlier image went through PhotometricColorCalibation without a problem.

Not sure what settings to use to upload here as a tif, so here's a temporary link to the (non drizzled) linear XISF file with just DBE applied. It's 211Mb:-

https://drive.google.com/open?id=1BM0X42z7P_BNYP1scbiQotvZrqM2uRXn

Cheers
Ivor

I'm having problems in Pixinsight getting Color Correction on a recent image I took. I've tried both Photometric Color Calibration & standard CC, but my background keeps coming out almost white... Any ideas? I can only get something half-decent by using Manual White Balance, but I'm not too happy with the initial result.

The only difference I've made to my usual process is that I'm now guiding the scope & took 180sec subs.

Any help much appreciated!
Cheers
Ivor

I could only get the USB connection to work with the SynScan app.

I quickly switched to using an EQDIR cable that plugs into a USB on the laptop and into the "Handset Controller" socket on the mount...

Cheers
Ivor

I thought it would also be worth cropping both objects at the original size taken. With the 200dps & Canon 600d, that works out at about 0.885 arcseconds per pixel.

Cheers
Ivor

I don't have an Atmospheric Dispersion Corrector, but am hoping to get one at some point. Looking at a few youtube videos' I think it's worth it. eg:

https://youtu.be/ELjSUNpzPUo

Cheers

Ivor

From last night (& early morning)... 46 x 3min subs. Canon 600D (astromodified) + SW200dps + EQ6, Bortle 6 sky with IDAS D2 light pollution filter. Taken with APT & processed in Pixinsight.

2nd night guiding, so next task will be to get more familiar with PHD2 and attempt dithering. PHD2 reported that the Dec had large backlash, but it calibrated & seems to have worked ok.

Cheers
Ivor

I've just started using a guidescope with a spare SW 9x50 finderscope converted to connect a ZWO ASI120MM camera (as per FLO's bundle), and have had one relatively successful session with it.

With this set-up, from the Guidescope Suitability calculator I get a ratio of 1:3.15 (with Skywatcher 130dps) and 1:4.84 (SW 200dps). However, with the 130dps I can't get the OTA to balance, so would need to either add weights to the OTA, or use a different guidescope.

I'd originally been thinking of getting the ZWO 60mm focal length 280mm Finder Guider, which I presume I could fit to the OTA tube rings using a Long (SW200dps) and Medium (SW130dps) Dovetail bar. This would give an improved ratio of 1:2.02 (130dps) and 1:3.11 (200dps), and be less prone to differential flexure.  An alternative would be to stick with the existing 9x50 setup for the 200dps & to get a smaller Mini-guide scope for the 130dps (eg the Astro-Essentials one which would give a ratio of 1:472).

Which would be the better route to go down?

I only expect to be taking 2-3 min subs, as I'm only shooting OSC with a DLSR & Bortle 6 sky.

Any thoughts / advice much appreciated!

Many thanks
Ivor

Is the scope balanced okay? On my EQ6 I have to use the extension bar with the weights positioned near the middle... but that is with a DLSR attached.

Enjoy your new scope!

Cheers
Ivor

Thanks @Erling G-P, I'm impressed! I always struggle with noise (although on SGL the images looked worse this time than when I load the jpg direct.

I've just downloaded the Topaz DeNoise software!

Cheers
Ivor

Very good for 10mins!