Planetary Imaging, problems advice please.

[Earl]

Getting the Planet on the sensor...

This is actually not as easy as I was hoping, and does waste a fair bit of time, Is a mirror flip system viable?

If I used a mirror flip system (im looking at the Bright Star one Bern sells, i can focus the eyepiece independently of the ccd, but im worried about extra length this adds Not really an issue with an SCT, I see the setup as been OTA>Focuser>Filterwheel>FLIP>CCD

If I was to use a mirror filp where would i put my powermate?

[Atlas]

If you get it centered in the eyepiece first then switch to your cam, it should get easier. Takes some practice, especially if the planet has a low light reflection. I normally run up the gamma on my cam and then back it off when I get it into view.

[Starflyer]

My routine goes:

1) Centre a bright star using an eyepiece

2) Insert the camera, turn up the gain / gamma, turn down the exposure, accurately focus it, lock the focuser, check the focus again.

3) Slew to your chosen planet and if its not visible in the camera remove it very gently, insert an eyepiece very gently - the idea here is to keep the fine focus you achieved for the camera.

The eyepiece probably won't be parfocal with the camera but as long as you can see a bright blob and then centre it in the EP you'll be in business.

4) Re-insert the camera, centre the (now very bright) planet on the sensor and then adjust your gain, gamma, exposure etc until your happy with it.

If you use a barlow etc then use that from step 1 and leave it in there through the process. I'm not sure what finder you're using but an optical finder makes it much easier to accurately centre a planet than a red dot finder.

Cheers,

Ian

[Earl]

After a chat with Bern, Im sticking an ST80 on the scope and will use this as a high power finder, once I have this aligned with the main OTA I should have no problems.

[JB80]

I had this nightmare last night and gave up after a couple of hours of trying so I know what you mean. One night everything goes smoothly the next it's a mess.

What made it worse was my motors would slip just as I got the x3 barlow image on screen, my fault for not keeping the screws tight enough really.

[Viv]

Oh yes.

I do tend to use, my camera (with backyard a fair bit of that), doing my neck in keep bending over to view up the tube. Not using the diagional at all.

goes something like this, which since getting the HEQ5 works well

Obviously align / 3 star check / etc

Attach camera & kick of software

Slew scope to planet position

Put planet in the centre (backyard has a drift screen, with cross hairs)

Then change over to additional extension tube, with web cam

Centre again to be exact

Add barlow to the webcam

It works ........

[lukebl]

After a chat with Bern, Im sticking an ST80 on the scope and will use this as a high power finder, once I have this aligned with the main OTA I should have no problems.

That's exactly what I've been doing. I've taken to using my guidecam to centre the planet, taking advantage of its vastly wider field of view.

I just get the planet centred on the chip in the main scope, then turn on PHD (any capture software would do) using the guide camera and use AlsReticule to put a cross-hair exactly on the planet. I then slew to a bright star, which I can get on the chip easily by centring on the cross-hairs on the PHD image from the guidecope, focus with the bahtinov mask, then slew back to the planet which again I centre on the cross-hairs. Saves a lot of aggro. I've been using it at a FL of 7.2m and it works fine.

[NickK]

After a chat with Bern, Im sticking an ST80 on the scope and will use this as a high power finder, once I have this aligned with the main OTA I should have no problems.

Red-dot-finder to rough location.

31mm BH + Vixen A80Mf to find the stars that make up the target and then I know the target stars are at least in the frame of the 383 on the SDP.. from that point it's just jogging the RA/DA.

Can quite happily find 19 arc sec targets that are invisible with the A80Mf too using this method!

I do the same with planets with the Titan.

[beamish]

Earl,

I understand your frustration, but I only use a cheapo £7 RDF on my C11 (I'd try and avoid adding more weight to the set-up what with flexure and balance issues) Are you using a crayford or the SCT's focuser?

As long as the finder is closely co-aligned with the scope, a X'd haired reticule/ or X'd EP would be a good investment. I go from long fl EP to shorter and keep "re-centring" the planet as I go using Synscan ( pressing "ESC" for a few secs then re-centre then press"enter").

Doesn't take long to get down to an 8mm fl then plus the barlow or go shorter eg 4mm , but be sure to get it centred. Then carefully remove & add the cam set-up and providing the the last EP was short enough the change in focus won't be too great but, more importantly, the planet will be on the chip.

Automated/electronic focussing of some sort would be a huge boon

Once you got a routine , it gets a lot easier

[Earl]

Thanks for all the input, I have a feathertouch crayford style attached, which I do intend to motorise when i have a spare £500... (ouch), this planetary imaging is not a cheap affair either.... LOL mugs game this i tell you mugs game LOL