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jimmyh1555
13-07-2018, 09:46 PM
Well, this evening - it being fine and no wind, I set up my BT200 F4 Neut with my new beaut ZWO OSC and prepared to have a go at Joopy.
In the daylight, I set up the guidescope crosshairs on a tree about 100 metres away and aligned the exact view with my Illuminated recticle 12mm EP in the eyepiece holder. I got them to pretty well align. Then I put the camera plus 2x Barlow into the holder, switched on the laptop Sharpcap and fiddled around until I got a good sharp picture on the screen , of the tree branches.
All seemed good. I knew focus would be a bit out when I actually hit Joop, but at least it should be in the ball park.
Well, dark came. I lined up Jupiter with the guidescope, switched on the tracking, then checked that Joop was in the centre of the cross hairs in the EP. It was pretty close. I took out the EP and put in my ZWO and switched on Sharpcap. Set screen to 640 x 420, gain to about 100, exposure to something like 0.1 sec, and nothing.....just blackness. I then tried to move that ROI box around to try to pick up Jupiter. No luck. Took out ZWO, put in EP, centred Joop again, took out EP, put in ZWO still nothing. Tried about a zillion more times. On one occasion when I was moving the scope with the flexi knob, I saw a white fuzzy thing flash by on the screen. Couldn't get it back. Tried more focussing, different gain, all hopeless. :(
After an hour I gave up as fingers were about to drop off with the cold.
HOW DO YOU EXPERTS FIND YOUR TARGETS? Do you all take an hour? I cant believe that go-to scopes are so accurate that you can just dial in the object and Bingo there it is... So How do you do it? Must be a better way.......:shrug::shrug:

leon
13-07-2018, 10:16 PM
James i feel your frustration, mate, i was always told keep it simple and slow down, it dose work. ;)
Your report is so long it takes ages to read, mate start again.:)

Leon :thumbsup:

xelasnave
13-07-2018, 10:24 PM
Last night I could not find the Lagoon Nebula and conclude it has been moved since the last time...
alex

Imme
14-07-2018, 08:02 AM
Only an hour?

.......you mean your fingers were just cold and didnt actually drop off???

My guess is you arent committed enough.

My first astro experience......the guys imaged while snow fell.

Try harder

doppler
14-07-2018, 08:17 AM
When centering Jupiter use a high mag eyepiece before fitting the cam and use a slow slewing speed when using the zwo cam, this will slow the bright "flash by".

glend
14-07-2018, 08:25 AM
You say you have a Newt, but you don't talk about the mount. If your going to be taking photographs your mount should be polar aligned for the Southern Hemisphere and be able to track and hold a star in the field of view. What kind of mount do you have? Is your mount aligned?

Secondly, eye pieces and cameras will have different focal points and thus require different focuser positions, try racking the focuser all the way in with the camera in place, then gradually back it out till the target object appears.

RyanJones
14-07-2018, 08:35 AM
I'm fairly new to all this so I don't consider my opinion as an expert one as you asked but here goes anyway. I dont know your setup all that well but what I do know from my scope and camera is that the focus points between my EPs and my camera is vastly different ( my camera being setup on primary focus ). Sometimes I will do the same process, find and look with my guide and EP then drop the camera in and I can't see a thing. Some number of turns later on my focuser and it starts to come into veiw. Through many hours of practice I know roughly the number of turns it takes. Then in addition I set the object I'm looking at as a custom object in my go-to so that it stays in perfect veiw.

I hope this helps :)

Also I might add, and this comes from even less experience, 0.1 secs will not nearly be fast enough as newtonians gather heaps of light. You'll probably find that you'll get no detail in your pics. They'll just look like a big bright round ball. Again, I have no experience with your camera but I know with mine I need at most 250th of a second and the lowest iso possible. I'm assuming in your program that is " gain "

PKay
14-07-2018, 08:49 AM
Hi James.

Each and every one of us has had that happen.
Nothing but more time with the equipment will give the experience to quickly find and hold target.

Techniques vary also.

My procedure is (with a GOTO mount and PHD guiding):

1: Get the mount aligned level and facing North South.
2: DO a one star align to get the mount tracking.
3: Spend as long as it takes to get good polar alignment.
4: REDO a one star align in the area of interest.
5: Dial in your target (GOTO), it should be on the screen somewhere.
6: Center the target. (If first time focus use bright planet or Moon)
7: Spend as long as it takes to focus.


Or you can do what Alex does and just point the scope upwards :)
Tip: Take a pair of gloves :-)

speach
14-07-2018, 10:29 AM
100 meters is a bit close for aligning your finder scope

rcheshire
14-07-2018, 11:07 AM
It gets easier... Take your time and conquer one obstacle at a time. The others have provided a good check list. Sometimes, I prepare the night before, do a trial run and sort out any issues ready for the following night/s. Then a quick recheck that all is aligned, focus, tracking, framing and camera settings and press go...

Rigel003
14-07-2018, 12:03 PM
Acquiring the planet at high magnification on the tiny chip of a planetary camera is a common problem. It's probably not in the small field of view or your ROI, or if it is, it's way out of focus to the point of being barely visible. Focus with the cam is different from visual focus, and if you add the barlow it's different again.

Centre Jupiter in the finderscope. Put a low power eyepiece in the main scope and centre visually. Then a high power eyepiece (plus barlow if you're using one) and centre visually again. Then put in the ZWO and open Sharpcap. Most important is to start with maximum field of view setting (not a ROI) and the exposure and gain settings both racked up to near maximum.When you've acquired it, centre it again and then adjust gain, exposure and focus. If you then insert the barlow, you'll need to adjust focus again by quite a bit, and ramp up the exposure. Once you've got it centred and focussed with the barlow, then adjust the field of view setting down to a smaller ROI and your frame rate will increase significantly. Hope this helps.

jimmyh1555
15-07-2018, 04:09 PM
Thanks, folks for your suggestions! I think it is more practice I need. Once I get any sort of fuzzy blob on the laptop screen , it is easy - I just then adjust focus, exposure and gain. It's getting the object on the screen that is the problem. With Jupiter, I use my BT200 mounted on my CG-4 and the tripod is just put on the pavers where I have marked the leg positions with paint. The South pointing and elevation I did with a compass and protractor and it's the same each time. . I have a simple battery drive fitted, which is fine for the Moon and Joop, as the time taken for exposures is very short:D
Your suggestion, Rigel003 is excellent! I will do that procedure next time. Yes, the time taken with the low power then high power EP and Barlow sounds good. All I need now is it to stop raining down here in TAS!:lol: