Derbyshire Dave

The moon over Florence Cathedral. Tried a few compositions but liked this one centred on one of the crosses on the side chapel..

Single exposure processed in Photoshop, Canon M5, 150mm, f10 1/125 second hand held.

Agreed, truly beautiful

On 29/04/2021 at 18:18, fwm891 said:

If you're using an OAG have you set the scopes focal length in PHD2?        Red Brain / Guiding...

Yes, focal length in PHD2 is set correctly, but your comment has made me wonder whether the guide star tracking parameters are correct?

This is the set up for the LX200 1260mm FL..

For my GT81 with reducer (focal length main scope 380 mm, guide scope 300mm) I have

Should my guide star tracking parameters be significantly different because my FL is significantly different?

On 29/04/2021 at 06:23, iapa said:

It feels like SGPro is waiting for PHD2 to settle in it’s guiding.

Daft question, but have you perhaps reinstalled PHD2 and not enabled server (Tools | Enable server)? That would prevent SGPro to get feed back from PHD2.

 

Enable Server is definitely ticked..

Re-calibrated the guiding, started PHD2 but did not start it looping. Started the SGPro sequence.. this started PHD2 into looping mode, I watched it auto choose a star, and then start guiding. Unfortunately this wasn't communicated back to SGP, or SGP did not register the fact, and so it just sat there saying:-

And the sequence never started. BUT -when I went into PHD and stopped the looping, SGP immediately recognixed this and stopped the sequence..

Unbelieveable

Yeah, I definitately have. Just been out and tried with the GT81 gear, it did work, but only after a sunstancial re-calibration. As I understand it, each calibration should be maintained as you change PHD2 profiles.

So, LX200 is back on the mount, I'll do a complete re-cal, followed by a guiding assistant. Then try again.

38 minutes ago, iapa said:

Looking at these, the only thing that comes to mind right now is whether the PHD2 profiles have been rename.

So, using your second image above, could you try clicking refresh to check the existing profiles?

Good thought. I did the refresh, the name was correct. Interestingly SGP opened PHD2 to do that, so there must be communications between the two. Setting up outside now with the GT81 setup, I'll report back.

Appreciate your help

42 minutes ago, iapa said:

I was wondering what the equipment profile you are using looks like.

Can you show us screen shots?

Sure.. Appreciate you asking..

  The SGP LX200 profile looks like this.. (Guiding tab first) ( I have tried with and without dither)

Under PHD settings, I have this..LX200_OAG is the correct PHD2 profile

Other tabs are..

15 hours ago, bottletopburly said:

Dave Astap has a ccd inspector in its tools menu if you already have that .

Thanks, I haven't got it, but I could download it. Thanks forthe tip Martin

2 hours ago, MartinB said:

I used to image with this reducer along with an SX AO unit and a qsi 532 camera.  A longer and heavier train than yours Dave.  Ccd inspector confirmed a small amount of tilt but I never had internal reflections.  Lots of people have used a similar set up successfully and I certainly think it better to use an oag at this focal length.  With your small pixels, even binned, you are better off with the reducer if you can make it work!  

Now you've spotted a likely reflection source you can hopefully sort it.

Thanks Martin. I hadn't heard of CCD inspector.

I'm not sure I have spotted a reflection source, just that if you are off centre in anyway, you can see that sort of circle. Can't see that I can do anything about them, will try and see if I can reduce the droop, if that's what it is.. Probably going to do a daytime test tomorrow, removing the focuser and see if I can adjust and get focus with the 'peg' mirror focuser. Same thread on both, so that will work. Just a little bit of extra infornation to the jigsaw.

29 minutes ago, CraigT82 said:

You can get it closer, you just need to use T2 thread spacers to fine tune the stopping point for the OAG as it screws to the filter wheel. You need to OAG turret to stop tight at the 'thin edge' of the filter wheel (as per pic).

Is there any shiny surfaces or edges on the inside of any of the kit in the imaging train? 

if I look down the back of the reducer, with my eye slightly off center, I can circular surface akin to what might be appearing in the picture, so yes there are..

43 minutes ago, ollypenrice said:

They are internal reflections but from where, I wouldn't like to say. To be honest, the sheer length of 'stuff' after the end of the drawtube really is a fundamental problem in this setup. As well as the internal reflections you have extreme and asymmetrical vignetting (top left in the image posted). When the leverage against the focuser is as long as this you have little hope of keeping the chip square on to the light path. I'm sure it isn't what you want to hear but I see this setup as fundamentally flawed. If I'm wrong, and others have made such a system work, I'll stand corrected.

Olly

 

Thanks Olly. I've never done this sort of thing before. My usual setup is a GT81 with a parallel guide scope.

I can believe what you say, if I look down the back of the reducer, with my eye slightly off center, I can circular surface akin to what might be appearing in the picture.

I have a fundamental problem, but if I shorten things a lot, will I not have an incorrect back focal length

I have a Meade Lx200, and a Celestron f6.3 reducer, connected to my ZWO ASI183 camera via some spacers and an off axis guider.

I get weird circular marks on the images, which appear to be some sort of reflections. There are several of these ‘circles’ of varying intensities in the image below. Tackling different targets results in these circles being seen at different points and intensities in the image.

So the equipment is:

Meade Lx200, with two stage focuser attached,

Celestron f6.3 reducer

Some spacers

ZWO OAG2 off axis guider

ZWO EFW filter wheel

ZWO ASI 183mm mono camera.

Guide camera is a ZWO 174

With the F6.3 reducer I believe that the back focal distance is 105mmm. I have tried various arrangements with distances from about 115 down to the latest, below, which has a back focus of about 95mm.

I have tried so many iterations that I am beginning to confuse myself, but I think I tried without the OAG and had no circles. I have tried removing the prism from the OAG, and taping up the hole to stop light entry, but in that case I still get the circles.

I am unsure how close the OAG should be to the filter wheel, but realistically it can’t go any closer because the holder for the guide camera is very nearly touching the filter wheel already.

I was wondering if any of you has seen anything like this, and can offer any advice on how I might try and track down this problem..

Just now, Derbyshire Dave said:

Thanks for the opportunity to have a go with this data guys.

Processing started in PixInsight, some noise reduction using MLT with a starmask on each layer, and then layers each stretched to a similar extent using the histogram tool.

Channels combined using channel combination.

This RGB image, Ha and luminance files (all stretched) saved as TIFF files for use in PS.

Main RGB image colour balanced in PS, then Ha added a an RGB layer in screen mode.

Luminance then added, a final tiny bit of star reduction, tiny bit of selective sharpening on the core.

 

Thanks for looking..

 

M33LumDFPost.tif 34.64 MB · 0 downloads

Whoops, meant to add the jpg, not tif.

Thanks for the opportunity to have a go with this data guys.

Processing started in PixInsight, some noise reduction using MLT with a starmask on each layer, and then layers each stretched to a similar extent using the histogram tool.

Channels combined using channel combination.

This RGB image, Ha and luminance files (all stretched) saved as TIFF files for use in PS.

Main RGB image colour balanced in PS, then Ha added a an RGB layer in screen mode.

Luminance then added, a final tiny bit of star reduction, tiny bit of selective sharpening on the core.

Thanks for looking..

M33LumDFPost.tif

Congratulations to the winners, wonderful results, an inspiration to us all.

HI,

  Thanks again for the great data.. Here's my shot...

  Processed primarily in PixInsight, including MLT for noise reduction, and combination with SHO_AIP script. Luminance layer created from Ha. Finished off in Photoshop..

On 16/11/2020 at 11:38, MartinB said:

Some great clean detail in there Dave, the tadpoles stand out very well.  A different colour scheme to the one I'm used to as well.

Thanks Martin. Having looked at this again, I think I have an issue with boosting the blue too much. I'm trying to track that dwon at the moment.. 🙃

On 12/11/2020 at 10:10, old_eyes said:

One of the values of this excellent project is giving us good data to practice our skills on. How about a mosaic? Just two panes would help us get into this skill. Not sure if they fit, but Heart or Rosette nebulas would be excellent.

Yeah, I agree, a mosaic would be a great chane ofr us all to improve our skills.

The tadpoles Nebula, IC410. Taken from my home in Derbyshire, on the William Optics GT81, ZWO ASI 183MM Pro. 35xHa, 32xoiii, 23xSii, all at 5 minutes. Combined with darks and flats in DSS, Processed primarily in PixIsight, finished off in Photoshop.

Hi,

 Wonderful data, thank you so much..

 Processed this primarily in PixInsight, finished off in Photoshop. Images from the three filters were sretched and then made starless with Starnet. Combined using SHO_AIP script, to a coloured starlesss image. Luminance layer created from the Ha alone. Coloured and luminance layers converted to Tiff format and combined in Photoshop. Bit of colour adjustment and a tiny bit of selective sharpening added.

Hi,

  I've been really imressend with the recent Crescent and M16 data, and have enjoyed having a go at it.

  I think it would be really useful to a lot of people to release some LRGB data on popular targets such as M31,  M81/M82 and M45.

  Maybe not even a competition, but there must be a lot of members who are not yet doing narrowband, to whom having some good LRGB data would be very welcome..

Hi,

Thanks for sharing the data, it's excellent.

Processing started off in Pixinsight with star alignment, channel combination and some basic histogram stretching as 32 bit data.

Then switched to Photoshop. Added a threshold layer and used the color sampler to find the darkest point of the image, then used that to help balance the colour channels.

A little bit of HLVG to tone down the green, then added a hubble palette tweak with selective colour.  Stretching using curves. Tiny tad of selective sharpening on the main nebula.