Thank you Garyh I will look more into this. Much appreciated.
Quote:
Originally Posted by Garyh
Welcome Benji!
Lots of great advice from members!
Most newtonians sold are for visual use unless you buy a photo optimised one like the Quattro range by Skywatcher.
With your saxon scope you will need to push the primary mirror up the tube by getting longer collimation screws and springs which are on the back of your OTA. Changing this is rather simple but you will have to collimate the scope again. 10-20-mm longer screws might get you in focus.
If you are on a budget, get yourself a tracking motor tor your eq3. You should be able to do lunar and very short deep sky stuff and learn the basics!
Cheers
Thank you Joe I tried with the skywatcher and the d750 and 80-200 combo, I did see the Orion once I stacked the images but the stars are all blurry. Could be few things that I am looking into - I tried this before I saw your latest post so I mounted the camera in the Dec bracket which was not the steadiest of setups. Also I chose a 15 sec exposure time at 200mm which I think goes against the 500 rule - but then again if the star tracker is tracking then relative motion should be zero and long exposure times regardless of focal length should be possible isn’t it ? Or is my thinking fundamentally flawed ?
Quote:
Originally Posted by OzEclipse
Hi Benji,
Bear in mind, they are taken from very dark rural skies. You won't be able to capture anything like that from the city. But get outta town and the skies the limit.
The Nikon 80-200 f2.8 is an excellent lens to start with. Mount it centrally on the polar axis of the Star Adventurer with a good solid ball and socket or tripod head (like the first photo), not hanging out on the dec bracket (like the second photo). The second photo is not a star adventurer, it's a much more solid polar housing to which I fitted the Star Adventurer Dec. That worked ok but the SA doesn't hold heavy camera+lens combos on the dec bracket. You'll get much better results centrally mounting /balancing the camera lens.
On your EQ mounting, you can just mount it on a dovetail plate and use it in place of the tube.
A little late, welcome to the forum!
I've been through all of this with a DSLR, I found a Bahtinov mask and image zoom a blessing. Especially when you have a heavier DSLR hanging off the back of the focuser.
I haven't read all of the posts in the thread and I'm sure either you or another experienced member mentioned it, either an app to trigger the shutter (which I think the D750 will do) or in my case of a D810, an intervalometer to avoid the slightest touch creating major blur in the images. Again (I did read this) a 200-33mm lens is a good start to get a feel for everything.
Thank you Joe I tried with the skywatcher and the d750 and 80-200 combo, I did see the Orion once I stacked the images but the stars are all blurry. Could be few things that I am looking into - I tried this before I saw your latest post so I mounted the camera in the Dec bracket which was not the steadiest of setups. Also I chose a 15 sec exposure time at 200mm which I think goes against the 500 rule - but then again if the star tracker is tracking then relative motion should be zero and long exposure times regardless of focal length should be possible isn’t it ? Or is my thinking fundamentally flawed ?
Benji,
1. Point the camera at a bright star.
2. Set live view to highest magnification (16x??)
3. Focus the bright star then look for faint field stars to appear around it.
4. Focus to maximise the faint stars and the lens is focussed
5. Don't touch the lens and shift to the target object.
Sorry I may have not explained properly - focus looks fine as I fine tune via maximum zoom in live view, but stars are trailing when I say blurry. I will keep tweaking and trying.
Tracking or not tracking?
If not tracked streaky stars are too long an exposure without guiding, if guided, polar alignment is off somewhere.
Tracking. I am checking if my polar alignment is good enough. If it is not then it may be possible that the angle of rotation the tracker is mapping to is not exactly how the earth is spinning on its axis.
I'm not sure on the mount you have, I haven't read the entire thread but I've had an issue with my EQ5 Pro where my latitude adjustment was just off. I wasn't using the markings on the mount I was using an electronic instrument to give me an accurate reading. One night I just adjusted it up the tiniest amount and it's been amazing ever since. This after I spent days making sure I got true south with solar noon and markings.
It is an experience thing though, one day you'll look back and forget you ever had the slightest issue. Experience comes with time and use, not that I'd know, it hasn't been clear here at night for ages.
Nice blue, warm (somewhat hot) day today turned into clouded over mess. I'm a little annoyed, I usually take a Milky Way image on my birthday, not today.
Following Leo’s post regarding Solar Noon , True South , and Polar Alignment
here’s how I find my True South line to set up up my tripod and mount before commencing polar alignment.
1/ Solar Noon Method to find True South Line ( attached )
2/ Setting tripod to align to True South
Hope this helps
Cheers
Martin
PS : I use a digital electronic level ( Accumaster ) to level the mount base of my EQ mounts tripod and also check altitude during polar alignment procedures ( refer link below )
I also use it to check my base is level on my 12” Goto dob visual telescope.
Bubble levels are ok but these are better
That Accumaster looks good Martin, I have a cheaper Aldi inclinometer and doubt it's accuracy somewhat but I also use the Samsung phone and a Samsung Galaxy tablet to check using whatever app my son has on his gear, possibly a built in 4 or 6 axis IMU, I'm not sure.
A quick mention with true south, my back yard has a slope, I have pavers set for an accurate level when I have my mount out. Last time I used solar noon I put a large, flat sheet of ply down and levelled it so my line was going across a level surface. Previous attempts not using a level section of ground and the line was distorting due to the slope which made all of my efforts useless.
Have a level area to find true south or it will be out and, out a fraction on the ground with true south is still a long way from any target in space. Probably more prevalent with GOTO but it will affect tracking.
That Accumaster looks good Martin, I have a cheaper Aldi inclinometer and doubt it's accuracy somewhat but I also use the Samsung phone and a Samsung Galaxy tablet to check using whatever app my son has on his gear, possibly a built in 4 or 6 axis IMU, I'm not sure.
A quick mention with true south, my back yard has a slope, I have pavers set for an accurate level when I have my mount out. Last time I used solar noon I put a large, flat sheet of ply down and levelled it so my line was going across a level surface. Previous attempts not using a level section of ground and the line was distorting due to the slope which made all of my efforts useless.
Have a level area to find true south or it will be out and, out a fraction on the ground with true south is still a long way from any target in space. Probably more prevalent with GOTO but it will affect tracking.
Leo,
Thanks for the tip
A level site is in my attached notes as I’ve experienced the same outcome
Cheers
Martin
Tracking. I am checking if my polar alignment is good enough. If it is not then it may be possible that the angle of rotation the tracker is mapping to is not exactly how the earth is spinning on its axis.
You can tell by looking at the direction of the star trails. If they trail in declination, it's polar alignment. If the trail in RA it's periodic error or drive accuracy or lag from poor balance or cable drag.
If you don't know how to tell RA from dec drift, post a photo of the Orion belt area here and someone will be able to help you.
Joe
