david_taurus83

Lovely image! Do you get many satellite trails in half hour subs?

First light with the new (to me) lens, a Canon 70/200mm f2.8 IS ii. Also a test if i can image from home with no LP filter whatsoever. Below is a stack of just under 2 hours worth of 30s subs. Focal length set to 100mm and stopped down to f4.

I aimed towards the Coathanger and tried to include a few other objects, Alberio near the top, M27, M71. Pretty pleased with it so far. I had to crop quite a bit out of the right side due to a bit of dust that had moved and couldn't be removed with flats and there was a bad vignetting artifact that needed to go as well.

57 minutes ago, han59 said:

Note in ASTAP there is a minimum star size setting which  default is set at 1.5 arc second to ignore hot pixels. Secondly it will ignore stars of one pixel (HFD<0.8) since they are most likely hot pixels.

For ASTAP it could help if you force the binning to 1 instead of auto=0 keeping the stars in the image larger.  The ASTAP CCD inspector will tell you the average HFD and star size in arc seconds.

Han

author of ASTAP

Thanks Han, I will give this a try!

17 hours ago, bottletopburly said:

I find 6 second subs and iso 1600 work well for Astap solving in 4 seconds ,.

I find if my lens is slightly out of focus ASTAP will solve with bigger star profiles but with good focus and tiny stars at short focal length it struggles.

No issues with PS2 or ASPS, just slower.

On 05/09/2020 at 22:30, wormix said:

Got this setup and running tonight -  It’s amazing!

It kept failing to sync and I was tearing my hair out trying to get to the bottom of it. Quick tip - check you actually input your coordinates correctly first before trying the more technical fixes!  

Hope you got to the bottom of it! If your scope is actually pointing close to your target already, you can auto populate the coords box by hitting the Scope Position button. It may be close enough to get it to solve.

4 hours ago, PaulB said:

This is a brilliant and very intuitive tutorial. I have followed your instructions and I have now setup APT and Point Craft for solving.

I use Plate Solving now. But I wasn't sure whether It was set up correctly. Thank you for this tutorial.

Have you considered offering this up for publication in Astronomy Now?

Thanks! I'm glad its still helping people! I should update it now though as APT has added ASTAP support. I find this very quick to solve, when it works, but I only have a 70/200mm lens now so its hit and miss at shorter focal lengths. PS2 for near solve and ASPS for blind solve still work well even at only 100mm focal length.

No, its never crossed my mind to reach out to any magazine though they would be more than welcome to publish. Its free for everyone to see on here anyway 🙂

They look pretty round to me. The smaller ones look square and blocky as they are probably undersampled. Have you taken a series of images and stacked them?

Are these cropped images? What camera are you using?

Did you check how many stars it was detecting?

Is the glow in a dark frame? If so then its electronic, if not, a light leak most likely.

I seen it through my 200p at a bortle 4 site a few years ago. Was the best moment of the star party I was at. Only had a UHC filter at the time but it popped right out. I also had a 71mm frac on the go as well and could also see it through that but just about, very faintly.

That doesn't sound good. What power supply are you using for the mount? My CEM25 is whisper quiet and its never made a sound like that. Are you using a quality serial to USB cable for connecting hand controller to laptop?

No darks? The flat darks only calibrate the flat frames. You need 240s darks at the same gain and offset to calibrate the lights. That should sort out the amp glow.

Strange. I would expect the centre region to be brighter. It looks like whay happens when you apply incorrectly exposed flats. What scope was this with?

I use the 6D. Can you post up your result or is that it above?

Resin is the way to go. Use a bicycle pump to blow any dust out of the holes first. Also, squeeze some resin off the nozzle until it starts mixing into a gun metal grey. It takes a few pumps to mix properly.

3 hours ago, ollypenrice said:

No, the point is that it won a competition calling itself, 'Astrophotographer of the Year.' Nobody wants to deny this person the right to experiment in whatever way they like and produce whatver image they like. The butt of the harsh criticism here is really the judging.

Olly

I get that, but I don't think the author would be happy about the japery being bandied about on this thread. Its not something I would have expected to see on SGL. If you visit his website he even lists this photo under his experiments tab. His solar eclipse images are incredible. He's clearly passionate about the subject and I don't think its fair to imply that his effort was lazy or amateur.

Anyway, that competition should be taken with a pinch of salt. Its akin to the so called Rock and Roll Hall of Fame. After all, a Hall of Fame with no Thin Lizzy is no Hall of Fame at all!

Ps. I'm not aiming my comment at any individual in particular but the theme of the thread appears to be pointing in that general direction.

Bit of harsh criticism on here? Im sure the author could have produced a more 'traditional' M31 if he wanted but he choose to do something different and he probably enjoyed capturing and producing it..

..and isn't that the whole point?

Hopefully this fares better than the Canon 135mm F2. I have read that this is the zoom to have for astro.

Now if I can just find a LP filter.

I never noticed bandinh when I had a 600D. Maybe if it got really hot in Liveview when I left the screen on and didn't flip it out.

So in the settings in PHD, there is the dithering scale. If its set to 1, then it will dither a random movement by 1 pixel or less. If your guidescope and camera pixel scale is 3 arc seconds, for arguments sake, then a dither scale of 1 means your mount will move a random amount between 0 and 3 arc seconds. If you change the scale to 2, then the dithers will be bigger, up to 6 arc seconds etc. The scale in PHD will multiply the scale set in PHD. So if its 2 in APT and 2 in PHD, it may dither up to 12 arc seconds.

Its probably easier to just leave either APT or PHD at 1, and only adjust the other to suit.

Are you dithering with PHD?

I updated all the boards on my CEM25 when I got it. All updates worked first time as per the manual. I have heard more issues with updating Synscan controllers though.

Hi Vin. You need to be very very close to focus when you begin. I used the AF1 with EKOS and the AF3 in NINA and APT. Works very well once you get it sorted.

Great stuff! Now leave it alone and never update it again!