M18, M21 & M23 Open Clusters

[laser_jock99]

A trio of open clusters in Sagitarius, again imaged from Mid Wales using an Altair Astro Star Wave ED80 scope. All are single, 120s unguided subs.

M18- a small cluster near the M17 Omega Nebula

M21- a young star cluster containg some 57 stars.

M23- a rich cluster of 150 maginutde 9 and fainter stars

[Daniel-K]

good effort jock, it looks like theres some small trailing on the 120sec sub probably a PA issue but 120 sec unguided is easily doable with out trailing with a 120. the other 2 cluster looking good too, where these taken from your dark site obsy?

[Gina]

Nice start

[johnh]

Thats a good haul of clusters in a busy area, these are forgotten because of the nebulas so good to see these.

John.

[laser_jock99]

good effort jock, it looks like theres some small trailing on the 120sec sub probably a PA issue but 120 sec unguided is easily doable with out trailing with a 120. the other 2 cluster looking good too, where these taken from your dark site obsy?

Taken from my obsy in Wales. I nearly have the guiding rig sorted. It seems to be working okay at my other site and is entirely transportable (I only need to move the netbook, Opticstar guide camera & wires between sites). Hopefully star trails will soon be a thing of the past!

[nightvision]

Is that the AG130 guide cam? Are you using PHD? Setting up the AG130 I noted some interesting interaction between the selected exposure time and the gain control (the gain slider needing to be set to an intermediate level prior to selecting the exposure), that way I get much higher contrast and a gain slider that actually functions. I was wondering if you have seen this?

[laser_jock99]

Is that the AG130 guide cam? Are you using PHD? Setting up the AG130 I noted some interesting interaction between the selected exposure time and the gain control (the gain slider needing to be set to an intermediate level prior to selecting the exposure), that way I get much higher contrast and a gain slider that actually functions. I was wondering if you have seen this?

Yes- it doesn't seem to function like I thought it should. I either see no stars on screen, or a lot. Can't find an in-between state on the level/gain slider bar.

[nightvision]

Yes- it doesn't seem to function like I thought it should. I either see no stars on screen, or a lot. Can't find an in-between state on the level/gain slider bar.

I'll have another look at how I got it working, it seems to be the auto functions in PHD that need some pre-exposure tweaks from the gain control to get anything visible. The camera works great with several other guide or capture programs.

From memory; If I leave the slider at one end then set exposure subsequently adjusting the slider doesn't deliver anything useful, usually just white-out. But if I set the gain control slider in the middle before setting a new exposure time I can then adjust the gain and everything looks great.