130P-DS First Light

[Stub Mandrel]

Well first light for me at least. 130P-DS with Skywatcher CC, modded Canon 450D, NEQ3 mount on EQ5 tripod.

I was determined to have a go, despite the thin cloud as it was the first night with stars for ten days. I went to a dark(ish) sky site, but the moon made this a waste of time. Naked eye I could probably see around 20 stars most of the time until midnight when only the moon, mars and saturn remained in Birmingham's light dome. So I did what I could between 10:30 and 12:00, only one light within a mile of me and I could read the LCD on my remote without extra illumination.

This is somewhere near the North America nebula. Astrometry.net keeps crashing and I can't find the exact spot in Stellarium - can anyone help locate this?

The thin cloud, moonlight and early time mean no nebulosity shows at all, but it shows excellent star shapes (IMHO) all over and the thin cloud gives the big stars lovely colourful haloes - it looks like the Pleiades! I have only stretched this, no colour correction. The slightly streaky background is caused by the direction of movement of the cloud. Thirty 30 second (any longer was pointless) subs@ ISO 1600.

I am pleased with this moon, although its much smaller than I get with the 150PL.

I tried to do M101 when the Plough went clear of a bit, but I forgot I haven't told my goto box to move DEC the other way after a meridian flip (oops). By teh time I had alined manually the cloud had set in for the night, so no DSOs. I did do Mars and Saturn but the tiny results don' do anything other than give a shape. I will stick to teh 150PL + barlow + webcam for planetary.

All said, I think this bit of kit will live up to its reputation!

[Stub Mandrel]

Stop press! Astrometry.net is working again. If nothing else, this proves my GOTO box is spot on (at least when it moves in the right direction!):

 

[wimvb]

Lovely starfield. Sometimes clouds can enhance an image. On my mobile device some stars look green. Maybe a touch of scnr (pi) or hlvg (ps) can clean this up.

I hope you can straighten out the issues with your goto box.

[xtreemchaos]

 im very impressed with what you can do with your new scope Neil, that moons a cracker. well done.  charl.

[Stub Mandrel]

18 minutes ago, wimvb said:

Lovely starfield. Sometimes clouds can enhance an image. On my mobile device some stars look green. Maybe a touch of scnr (pi) or hlvg (ps) can clean this up.

I hope you can straighten out the issues with your goto box.

I agree, I have done a slight push from green to magenta, then applied HLVG to get rid of a few last bits of green.

Then dec issue will be straightforward to sort :-)

[michael.h.f.wilkinson]

Nice first-light results

[The Admiral]

3 hours ago, Stub Mandrel said:

The thin cloud, moonlight and early time mean no nebulosity shows at all, but it shows excellent star shapes (IMHO) all over and the thin cloud gives the big stars lovely colourful haloes - it looks like the Pleiades! I have only stretched this, no colour correction. The slightly streaky background is caused by the direction of movement of the cloud. Thirty 30 second (any longer was pointless) subs@ ISO 1600.

All said, I think this bit of kit will live up to its reputation!

I think that's worked out rather well considering the conditions. I don't agree about no nebulosity though, it is clearly visible in your second version. (Edit. Well at least on my tablet, by no means so obvious on my PC)

The stars look a good shape; did you use a coma corrector with the 'scope, or is that straight out of the focuser? Was there much cropping?

Ian

[Stub Mandrel]

Might be worth adding a few comments on the scope itself.

First, it's tiny - half the length and smaller diameter than the 150PL, much easier to move around. Heavier than you expect though as the mirror is not hugely smaller and the focusser is MUCH bigger.

The best bit, from my perspective, is the two-speed focuser which is very smooth and appears well made, it was pleasure to use visually and with the camera. It has what appears to be a locking knob, but without really wrenching on it it doesn't appear to lock? It would be a nice upgrade for a 150PL if sold separately.

Despite rumours to the contrary with  the 450D and coma corrector fitted it balances easily enough without going to the end of the dovetail.

Just like the 150PL the o-ring for the finder was missing, I couldn't find one big enough so cut two up and poked them into the gap. Amazing how a short f/l makes aligning the finder less critical.

Collimation was stressful, secondary was way out (probably through transport as it was sold 'collimated recently') I think the secondary adjustment screws have been overtightened and damaged the surface they bear on. Much harder to get the secondary right than my 1509PL that uses the same support system. I might rotate the spider 180 degrees so each screw bears on a new surface. In contrast the mirror was almost spot on once I got the laser spot in the middle of the ring and just a couple of tweaks to get it back up the spout where it came from, although the locking screws were loose.

I couldn't do a lot to test visually - the moon looked stunning,  mars and saturn were small but pin sharp.

[Stub Mandrel]

1 hour ago, The Admiral said:

I think that's worked out rather well considering the conditions. I don't agree about no nebulosity though, it is clearly visible in your second version. (Edit. Well at least on my tablet, by no means so obvious on my PC)

The stars look a good shape; did you use a coma corrector with the 'scope, or is that straight out of the focuser? Was there much cropping?

Ian

You're right. I've attacked the gamma control. It's brought out an artefact along the bottom edge which I have cropped off. This is a jpeg so may be noisier:

[Stub Mandrel]

Update! The knob on the focuser does lock it, it just doesn't stop the knob rotating, it must be a friction drive not a rack and pinion. Focusing with live view and bahtinov mask was a synch.

[Adam J]

On 15/07/2016 at 16:15, Stub Mandrel said:

Might be worth adding a few comments on the scope itself.

First, it's tiny - half the length and smaller diameter than the 150PL, much easier to move around. Heavier than you expect though as the mirror is not hugely smaller and the focusser is MUCH bigger.

The best bit, from my perspective, is the two-speed focuser which is very smooth and appears well made, it was pleasure to use visually and with the camera. It has what appears to be a locking knob, but without really wrenching on it it doesn't appear to lock? It would be a nice upgrade for a 150PL if sold separately.

Despite rumours to the contrary with  the 450D and coma corrector fitted it balances easily enough without going to the end of the dovetail.

Just like the 150PL the o-ring for the finder was missing, I couldn't find one big enough so cut two up and poked them into the gap. Amazing how a short f/l makes aligning the finder less critical.

Collimation was stressful, secondary was way out (probably through transport as it was sold 'collimated recently') I think the secondary adjustment screws have been overtightened and damaged the surface they bear on. Much harder to get the secondary right than my 1509PL that uses the same support system. I might rotate the spider 180 degrees so each screw bears on a new surface. In contrast the mirror was almost spot on once I got the laser spot in the middle of the ring and just a couple of tweaks to get it back up the spout where it came from, although the locking screws were loose.

I couldn't do a lot to test visually - the moon looked stunning,  mars and saturn were small but pin sharp.

Yep it balances with a 450 and coma corrector fitted, the problem comes when you go beyond that and start adding finder guiders and heavier cameras. At that point the way to get balance is to change out the dove tail for a longer one.

[Skyline]

A nice counter weight balance is to use a skywatcher 33.3 cm dovetail on the tube.