Jerry Barnes

I recently was given a small gigabyte PC which I planned to use to control my mount and cameras.  A long ethernet cable would let me sit in the warm and monitor the session via remote desktop from my laptop.

I could not get the mount to be recognised by the PC, whatever I tried it would not create the virtual com port.   Windows update, reinstall software and drivers, nothing worked.  Then I tried adding a USB hub between the mount and PC, a cheap 4 port unpowered one costing less than £10.  All was fine after that, though my MC2600 didnt like to be connected through it.  It was a USB3 hub and I think the mount is USB2 so that might be some clue to why it worked though I think I plugged it into a USB2 port.

I have found USB connections to be very picky and seem to be resolved by trial and error rather than deduction but this might possibly help somebody else with a similar problem.

Cheers

Jerry

I sympathise.  I haven't managed to  capture anything for two months now.  I was hopeful of two or three hours at the weekend but I had issues getting the camera connected properly (dodgy usb?)

Seriously wondering if I should sell up and start photographing clouds instead.

it makes sense, dont mess if its not needed.

thanks

Jerry

I was wondering if I should attempt to clean the mirror in my 200 PDS while the nights are still too light to do anything.  Depending on the angle of the light reflecting on it its either perfectly clean and really sharp or has a very light layer of dust.  I guess that means its a little dusty but not bad enough to make a signicicant difference to an image.

Is it the right thing to leave well alone until I notice a problem?

Cheers

Jerry

My GEM45 seems quite happy with my 200PDS for what its worth.

On 09/03/2023 at 23:45, Altair8389 said:

Hi Anthony,

How does the telescope/tripod not topple over ? How is the whole thing stable on the trolley. Did you do a DIY job on this trolley?

Another problem: how do you lift the tripod and OTA on the trolley and also how do you lower tripod and OTA down on the ground where you are imaging?

Thanks.

The COG is over the centre on the trolly so its quite stable (I only move it on the flat) and the legs sit over the wheels so there is no real strain on the structure.   I dont lower the tripod to the ground, just leave it in place, the brake on the wheels stops it moving.  I plan to fit screw down legs for added protection against movement but havent go round to that yet.

Definately home made!

I keep my set up in the garage and wheel it out and attach the camera when needed.  It takes about 15 minutes to polar align using iPolar and connect the pc etc.  Saves carrying it as well.  My garden backs onto a public field so its a good compromise between ease of setup and security.

I've had some success with GraXpert when struggling with PixInsight.  Could be worth a try.  You need to give it a tiff so save the fits header info by dragging the triangle at the bottom of the PI onto the worspace then drag that process icon back onto the image when you read it back in.  Took me a while to twig that one so I didnt loose all the useful info.

I like that, especially as it doesnt stay high enough in the sky for very long.

I wish I'd read this thread earlier, very helpfull and I realise I need to increase my back focus having essentially the same setup.  Thanks for starting it.

My first attempt resulted in enough cloud to make tracking impossible so this is the first usable image.  M33 or Triangulum, 5 hours of which I used 80% Stacked in DSS for speed and then pixinsight, I’ll add more data when the clouds go….  I don’t seem to have got much colour but I’ll look at that later, super pixel mode shouldn’t make a difference according to the documentation.  I've probably also got a back focus issue so thats something else to look at.

Anyway I’m satisfied enough for the first go.

The scope and mount add up to a fair weight so I made a little trolly for it.  Now I can wheel it out of the garage almost ready to go.  The weight is all on the wheels so the frame doesn’t need to be sophisticated. 

Just aquired a longer scope, 200 PDS and a comman correcter, so I can get sensible sized images of smaller targets.  I hadnt really appeciated how big it is untill I took it out of the box!  

I've just tried this out and liked it.  I was able to remove a gradient easily which I was having problems getting rid of in Pixinsight.  Good job and great price!

A feature request to think about for the future would be to add support for xisf format.

Thank you, the point about offsets put me on the right track with my problem.

I've had another go at stacking using the suggestions.  I did find I had to check CFA for the flats (so Pixinsight would debayer them), if I didnt do that the flats didnt show in the calibration diagram.

The other thing I found was, I suspect, the main cause and that was user error!  I've started to use NINA and that's really great for framing the images.  I was using APT before and I still find it easier for flats and darks.  I'd managed to get a mixture of camera offset settings.  Lights at the default of 50 and flats and darks at 0.  I've now redone all the calibration at offset 50.  I haven't disturbed the optical train so the flats should be there or there abouts.

Yes, lovely image.

Thanks Ivor.  I'll try those suggestions.

Jerry

I have Topaz Denoise, I dont use for astro much though.  I tried it on your image and it wasnt that effective and I think Alacant's advice is good, take a few more hours of images.

Do you mean the variation in lightness across the centre circle, a bit like clouds?  Is your teeshirt stretched uniformly and if you take another set of flats do you get the same pattern or a similar one?

What do you get if you compare a stack with and without the flats?  

I'm having trouble with flats so its an interesting topic.

Something is going wrong with my flats and I cant work it out.  Attached are two stacks done using Deep Sky Stacker.  One using flats and the other without.  The flats version shows significant lightness on the left corresponding with the darkness at the edge of the flats.  It looks like its a gradient but it not there if I dont use flats.   I’ve tried using different exposures for the flats and using a light panel (cheap one) and pointing at the sky.  It doesn’t seem to make any difference, better results without using flats.

Also attached is the master flat created by DSS.  The stacks are done with 60s subs, 60s darks and 1.3s flats and 1.3s dark flats.  1.3s came from the NINA flat wizard but .5 sec gives the same effect.

So I’ve tried different flat exposures and methods of taking them and different software for stacking (Pi and DSS but DSS is faster for a quick test).  Any pointers for what to try next?

Zenithstar 61 with flattener plus l-enhance and ASI 2600MC pro at -10c

Attached

DSS

Stack with flats, original tiff and stretched jpg (basic auto stretch in Pixinsight, no other processing)

Stack without flats, original tiff and stretched jpg

Master flat

AutosaveFlats1.3s.tif AutosaveNoFlats.tif MasterFlat_Gain100.tif

2 hours ago, Len1257 said:

Incidentally the size of the scope and flattener has little to do with what the focuser has to cope with. It's the image train that counts i.e. camera, filerwheel, OAG etc. You haven't mentioned that at all?

Duh!  Thats so obvious when you point it out, I should have realised that before.

I have the ZWO focuser and it works fine when controlled  by NINA but I think your scope might be too heavy for it.

I was post processing some images from a few nights ago and found some extra "nebulosity" between the Pelican and the North American Nebulae.   I was sure it shouldn't be there and yes, it was definitely surplus.  It took a while to track down and eventually I found it in the darks.  Thinking it must be some light leak, probably from the filter drawer, I re-took darks after wrapping the filter drawer in some old ties.  Still didn't work.

I did wonder if there was some light reflecting off the Bahtinov mask which is built into the cover on the scope (normally covered by the screw on cap on the cap) but I'm not going to worry about it.  After taking the camera off the scope and putting screwing the cap onto the camera (metal cap) the problem was bypassed.

Now if I can just sort out those flats........................

some small compensation for missing the Practical Astronomy Show tomorrow due to covid.   At least it means I wont have to think up a reason why I just had to by a new scope.

Thats an interesting thread quoted above, thanks for that ONIKKINEN.  It will take some study...