Max exposure before star trails form

[MARS1960]

12 minutes ago, SteveBz said:

Hi Mark,

Yes I focussed on Vega yesterday, but not using live view, just trial and error.  When you say 10x live view is there a magnification setting on Live View or are you using a PC?

Regards

Steve.

There is, but not sure on yours, i have two little buttons at top right to zoom in or out, i think yours may have them.

[newbie alert]

8 minutes ago, cjdawson said:

Actually, using the barlow will be a disadvantage.  It will lower the F/ratio of your scope meaning that you need longer exposure times.  It will also magnify any errors, this will make your life a lot harder and frankly give you lots more frustration.

On the size subject m31 is quite large..i can only just fit it in the frame.. once you have stacked it and bought out the detail in the dust band you will realize how big the target is

[SteveBz]

1 hour ago, spillage said:

I guess the c6n and c8n are not the same.

 

So here are some photos of my (newly discovered) attachment screws:

Focuser barrel:

Without barrel:

With t-ring:

And finally, if I shaved that lip off the barrel it would screw inside the t-ring meaning one thing less to lose on a dark night.

What do you think?

Tx

Steve

[SteveBz]

5 minutes ago, MARS1960 said:

There is, but not sure on yours, i have two little buttons at top right to zoom in or out, i think yours may have them.

Hmmm.  I have something like on the Nikon but not on the Canon.  However the Nikon is soooo sensitive to light pollution.  Everything comes out yellow.

I'll investigate.

[SteveBz]

4 minutes ago, newbie alert said:

On the size subject m31 is quite large..i can only just fit it in the frame.. once you have stacked it and bought out the detail in the dust band you will realize how big the target is

Oh my.  Stacking!

Well of course it was going to come up, but I just can't get my head around it.  Well my head understands, but the software doesn't cooperate.

I have Registax, Siril, StarStax and AutoStakkert and they are all just horrible.  I'm on Linux so most Windows software doesn't run.

What do you use?

Steve.

[MARS1960]

2 minutes ago, SteveBz said:

Hmmm.  I have something like on the Nikon but not on the Canon.  However the Nikon is soooo sensitive to light pollution.  Everything comes out yellow.

I'll investigate.

You could download a free trial of backyard EOS, it is a great piece of software and it will make focusing a breeze, give it a try and have a play in daylight.

[SteveBz]

2 minutes ago, MARS1960 said:

You could download a free trial of backyard EOS, it is a great piece of software and it will make focusing a breeze, give it a try and have a play in daylight.

I'll try it.  It's Windows software so it might not be easy on Linux.  But I'll download it over the weekend and see what happens.

Thanks

Steve

[spillage]

sorry its more of a ring that you can undo.

[SteveBz]

7 minutes ago, spillage said:

sorry its more of a ring that you can undo.

But am I right in thinking that what you have photographed above (in your kitchen by the look of your beautiful granite worktop) is different from the thing that I photographed (in the shed, since you ask)?  It seems to be a totally different fitting.

[spillage]

 

I Think my smaller scope has a different focuser than yours.  I unscrewed my 1.25" and then attached my t2 to the thread on the adapter. 

[newbie alert]

2 hours ago, SteveBz said:

Oh my.  Stacking!

Well of course it was going to come up, but I just can't get my head around it.  Well my head understands, but the software doesn't cooperate.

I have Registax, Siril, StarStax and AutoStakkert and they are all just horrible.  I'm on Linux so most Windows software doesn't run.

What do you use?

Steve.

Deepskystacker for nebulas/ galaxies..it dont like the moon as i think it uses star formation to align the stack

[SteveBz]

3 hours ago, newbie alert said:

Deepskystacker for nebulas/ galaxies..it dont like the moon as i think it uses star formation to align the stack

I'll try it.

Thanks

Steve.

[SteveBz]

4 hours ago, spillage said:

I Think my smaller scope has a different focuser than yours.  I unscrewed my 1.25" and then attached my t2 to the thread on the adapter. 

Ok, Yes mine can switch between 1.25 & 2 inch.  I mostly use 1.25, because 2" lenses are so much more expensive.

Regards

[happy-kat]

The no eq challenge thread are all using (the active posters) much shorter focal length, I think your c8 with a barlow is very long. Why not use your 350d with a camera lens, m31 can image really nicely with a 135mm camera prime lens. Don't lose hope just shorten the focal length demands you are making.

[SteveBz]

1 hour ago, happy-kat said:

The no eq challenge thread are all using (the active posters) much shorter focal length, I think your c8 with a barlow is very long. Why not use your 350d with a camera lens, m31 can image really nicely with a 135mm camera prime lens. Don't lose hope just shorten the focal length demands you are making.

So I should probably still put it on a stable mount.  Do I use the CG5 without the scope.  I feel if I put it on top of the mount all the focusers and stuff will get in the way.  Then pointing it without a finder scope?  It all seems a bit challenging.

Regards

Steve.

[ollypenrice]

9 hours ago, spillage said:

I am not way an expert at all in this but it looks like your pa is out as all the stars are drifting in one direction and focus is out a bit.

If PA is out the image will tend to show rotation rather than a single direction of drift. Star elongation in one direction is most likely to be caused by periodic error. When stars look like dumbells or 'figures of eight' the cause is often backlash.

The first thing you need to know is how your chip is aligned with regard to RA and Dec. Put your chip into landscape or portrait mode relative to RA and Dec. Just take a 5 second exposure while slowly slewing and this will give star trails which show the angle of the camera relative to the axis on which you slewed. When you have used this to set your camera along RA and Dec you can tell which axis is trailing and you can think about a solution.

The Barlow is slowing you donwn by a factor of 4 on exposure time and making your pixel scale unrealistically fine, so finding a way to get to focus is really the answer.

Olly

[happy-kat]

12 minutes ago, SteveBz said:

So I should probably still put it on a stable mount.  Do I use the CG5 without the scope.  I feel if I put it on top of the mount all the focusers and stuff will get in the way.  Then pointing it without a finder scope?  It all seems a bit challenging.

Regards

Steve.

I thought as you referenced the no eq challenge thread that you had a motorised altaz mount. I'll bale out if you are using an eq mount as can't add anything.

[SteveBz]

15 hours ago, newbie alert said:

Deepskystacker for nebulas/ galaxies..it dont like the moon as i think it uses star formation to align the stack

Well, amazingly I have managed to download Deepskytracker and install it in Linux.  I'm trying it out.

[SteveBz]

17 hours ago, MARS1960 said:

You could download a free trial of backyard EOS, it is a great piece of software and it will make focusing a breeze, give it a try and have a play in daylight.

Hi Mark,

Well I struggled with Backyard EOS on Linux, but I found a programme called gphoto2 which runs on Linux and allows me to see through my camera with a laptop.  I'll give it a try.

[newbie alert]

39 minutes ago, SteveBz said:

Well, amazingly I have managed to download Deepskytracker and install it in Linux.  I'm trying it out.

Give it a go but look at the many tutorials on u tube.. best of luck

[SteveBz]

On 01/12/2016 at 11:48, spillage said:

I Think my smaller scope has a different focuser than yours.  I unscrewed my 1.25" and then attached my t2 to the thread on the adapter. 

Well here are some unprocessed photos (Pleiades, Andromeda and Orion Nebula) from last night with the camera attached the way you suggested.  I also think that polar alignment is much better.  Focusing is still a bit ropy, I think it really needs to be done with a laptop attached: