Help Getting Started

[Gerhard]

I might just reduce the interval to 10 secs, to shave off 8 minutes off the total run... I'll be in my car out of the cold while the camera does the work.... :-)

what can I expect to see on the individual subs? not a lot, I imagine...

I'll try shooting with 800 ISO...

[Knight of Clear Skies]

This is a 30 second single exposure with a kit lens at ISO 1600 and f3.5, gives a faintly visible Milky Way.

There is some trailing, 30 seconds is a bit long for stacking. I'd probably try ISO 1600 or even 3200. Makes it easier to check what you are doing on the camera display and won't make a lot of difference after you stack - you'll be adjusting the brightness levels anyway.

[Gerhard]

How much difference does the modification to the camera make? I read on Carole's page: "a lot".... :-/

[Gerhard]

I amazed myself: I added my flickr astronomy set to my signature, and was looking at those old photos, and noticed I already captured M42!!! :-DDD

one down... eheheheh... 6 years ago already...

[Mark62]

Now that is an area where I have not had much success at all. In particularly I find it very difficult to get focus with the stock lens.

I have canon stock lenses. I set the up through the day on sim ting far away then with tipex I have marked the lense and focus ring I have done 55mm 200mm and 300 mm on one lense and 18 mm 35 mm and 55 on the other then just line the marks up. Seems to work and u have some sort of reference

Mark

[carastro]

 Knight of Clear Skies

where will you post up your tutorial and how will we know?  

Will you come back to this thread and post a link please?

Thanks

Carole 

[carastro]

I set the up through the day on sim ting far away

Where I live there is nothing to see far away (too many houses) unless I go for a car ride.   I did try to get focus on wide field when I went to Iceland to see the aurora and did as you suggested

marked the lense and focus ring

But it just doesn't seem any good when I do things like the milky way, I am sure this is out of focus using those Marks.  I did this by getting jupiter as small as possible before I went to Iceland.

This image was taken piggy back with the DSLR while I was imaging another object with the scope and CCD.  

[Gerhard]

I will be glad to get an image like that tonight! :-)

just checked the weather, though: clouds they be a-comin'... :-(

[Mark62]

I agree with Gerhard. Been sat in Dalby Forest for 6 days and only managed 3 hours observing. And it's not looking promising for tonight eather

[RichM63]

Can it not be done by tricking the lens.

Landscape mode let the camera focus on something as far away as it will see, then use switch on lens change to mf change camera dial to manual and carry on setting up the image.

I have yet to try this out but it theorises it might work.

I've tried this a couple of times and it does seem to work. Although I was going for the Moon with the 300mm.

The thing is do not go anywhere near the focuser or move the camera in any way after doing this.

Thus set the M mode parameters before going for this type of focussing, the M settings are retained even if the camera is switched off. (700D), so if you know what you will be using, then these can be set indoors where you can see where the buttons etc are.

I find the view finder sharper than live view, but I'm still very much getting to grips with the camera.

(pity that Canon didn't think to make the buttons slightly different heights for thumbing around in the dark)

[RichM63]

Gerhard, given that -

Very basic: DSLR on static tripod... But my remote arrived, and I already programmed it for 50 20s subs. WIll do darks and bias as well, if just for exercise.

then -

another 20secs. for cooling of the camera... too little?

Waaaay to much IMHO, you are asking for a total of around 35 mins on a 'static' tripod, the whole sky will have moved, most likely out of range that any stacking program can handle.

Don't forget that what you have set is effectlvely 1sub, 1 pause, 1 sub first minute, followed by, 1 pause, 1 sub, 1 pause second minute, until you reach the end of the sequence. (in real time).

Star trails could be fun, with fewer, longer exposures.

[Knight of Clear Skies]

Gerhard, given that -

then -

Waaaay to much IMHO, you are asking for a total of around 35 mins on a 'static' tripod, the whole sky will have moved, most likely out of range that any stacking program can handle.

Don't forget that what you have set is effectlvely 1sub, 1 pause, 1 sub first minute, followed by, 1 pause, 1 sub, 1 pause second minute, until you reach the end of the sequence. (in real time).

Good point, if you're going to shoot for that long on a static tripod you'll need to re-frame from time to time, which could be a bit tricky.

where will you post up your tutorial and how will we know?  

Will you come back to this thread and post a link please?

Thanks

Carole 

No problem. It will probably go up on the Caradon Observatory site that I manage to begin with, but I've been thinking about making my own and this might give me a push.

Where I live there is nothing to see far away (too many houses) unless I go for a car ride.   I did try to get focus on wide field when I went to Iceland to see the aurora and did as you suggested

But it just doesn't seem any good when I do things like the milky way, I am sure this is out of focus using those Marks.  I did this by getting jupiter as small as possible before I went to Iceland.

This image was taken piggy back with the DSLR while I was imaging another object with the scope and CCD.  

The focus could be a bit out or is the lens wide open - did you try stopping it it down a bit? I got quite bloated stars with the kit lens wide open and mostly use f4.5 or f5.0 when stacking. The NA nebula looks well defined so I suspect star bloat, checking the individual subs should help, if it's a focus problem they will be large in every exposure.

[Gerhard]

still at home... fog is coming in, so no go tonight...

so if 50x20s is too much (in fact I WAS amazed the stacking programmes would be able to deal with such a long run, with accompanying rotation issue), for milky way, what should I be looking at?

could 10x20s be enough already? with maybe shorter cooling down intervals?

unfortunately, I have at least a week and a half before I will be able to go out again, because two busy weekends and the week shows rain rain and more rain... :-/

my celestron c8 friend would like to try out my tring adapter as well, so when seeing is good, I will also be looking at shooting andromeda, for starters. what kind of subs should one do there? more / less than wide field? longer, I imagine? 

Thanks again for your help!!! :-)

[happy-kat]

Depend on your friends mount

[Gerhard]

http://www.astronomyasylum.com/c8.html

This is exactly his scope. An oldie...

[happy-kat]

I could be wrong but that looks like an AZ fork mount.

So probably looking at 1 second exposures as it wont allow for rotation and the super long focal length of the scope.

However brilliant for planets and the Moon.

[Gerhard]

It is motorized. A strange kind of equatorial mount. You polar align it, and afterwards the motor always keeps whatever you point at centered. I saw it in action already.

Btw, his doesn't have the C5 as a guide scope.

[happy-kat]

Sounds like it tracks but that is not necessarily the same as following the Earth's rotation.

Perhaps the mount is different to the one in the link you gave.

[Gerhard]

On that page it doesn't show well with the tripod, but maybe it's better from this view:

http://upload.wikimedia.org/wikipedia/commons/8/8e/C8_smaller.jpg

I made a photo of it, and it's exactly this setup. my friend told me it's equatorial, and follows rotation....

anyway, the stars are fixed in the scope, so I should be able to make long subs, no?

[carastro]

It's Alt/AZ on a wedge which enables it to polar align and follow the Earth's rotation better than Alt/Az without a wedge.  But it's not a true Equatorial.

Yes you can image with this set up.  Not sure how you guide though, but I know people who have done it.

Carole

[Gerhard]

So just to try, for example for Andromeda, how many subs of how long? Ten of two minutes?

[happy-kat]

Ask your friend how long the subs are he can push from his setup.

Otherwise try 30 seconds.

Then 1 minute.

If still no trailing then try a bit longer.

Then take many once you identify the sweet spot for that session on the object you aimed at. Because how well the mount is aligned and where you point your camera in the sky can influence how successful it will be.

[carastro]

Might be a good idea to start a new thread entitled "Imaging on a Forked Mount with a wedge" that way you might get replies from people who have imaged with this set up.

Carole