Gumminess8083

Hmm, interesting observation!

I'll try taking everything apart once again and re-tightening all the parts!

10 hours ago, pipnina said:

Could be the front cell or the focuser aren't quite done up tight? I've had that issues before...

Am I correct in assuming that fixing this would require me to open up my scope?

20 hours ago, Stuart1971 said:

What software do you use, as NINA had region of interest autofocus, so you can choose an doughnut type area…looks like this, area inside the dough it is used for focus, and the inner and outer lines can be altered 

 

I do indeed use NINA, so I'll try that out next time!


I also have a small update—I remembered that I had taken some test shots while trying to figure out the best exposure time for my target the other night, which were taken before the meridian flip, while my normal LIGHTs were taken after.

Here's a comparison:

S filter before meridian flip

S filter after meridian flip

H filter before meridian flip

H filter after meridian flip

O filter before meridian flip

O filter after meridian flip

If the problem was caused by sensor tilt, I would see the "gradients" in FWHM always in the same corner, since the image would always be aligned with the camera.
In my current situation, the gradient seems to be flipped by 180° after the meridian flip, suggesting that this is not caused by sensor tilt nor collimation errors, but by sommething else altogether!

My best bet would be the guiding, as my mount is not that good at tracking currently. I should get a belt conversion kit for it soon, though, so maybe that will help me fix this problem.

...This is as far as my knowledge can take me. If there's some other factor at play, I cannot figure out what it could be, beside astigmatism.

9 hours ago, Stuart1971 said:

There is also bad astigmatism there too, as you can see by the star shapes, they look like bloated crosses, try focusing about 2/3 from the middle of the image to even out the curvature, it should help, I don’t think that is all tilt at all….👍🏻

Is there any way to do it with an autofocuser? Or even to fix it at all?

I usually let an autofocus routine take care of it, so I would have to find a way to change the settings on there.

Anyways, looks like this weekend is gonna be pretty clear, so I will do some more tests, such as rotating the camera and taking some more measurements with shorter exposure times, so as to eliminate other variables such as tracking, etc.

Hopefully I'll be able to sort everything out, eventually!

Thanks again, everyone. I'll report back if I have news

OK, I finally have an update!

After months without a single clear night, I was finally able to take some pictures yesterday and the day before

I have included all the measurements in the following album: https://imgur.com/a/T4GqSd8
 

All pictures were taken with the same setup, in the same position and without moving it. The first night was perfectly clear, while the second was quite hazy, but I decided to shoot anyways, just to see if I could get something decent out of it. I have also included some old pictures before "calibrating" the sensor tilt, to see whether it made a difference.

Now, I am not an expert, far from it, but, from what I can see, considering that the camera has been clibrated and should now be flat, the problem still seems to be present...

Could it be that the problem lies with my tracking? I tried using the guiding help tool in PHD2 for the first time, and it seems that my error is around 3400 ms.

If anyone has any further ideas, I'd be happy to try them out

Edit:
https://drive.google.com/drive/folders/1-H2JRX_zegJOhZemnRRRL9razu7LcvnZ?usp=share_link
 

I have uploaded some of my new shots from these past 2 days in here

Edit 2:
@gaz81 Thanks for the suggestion! Should I still attempt to collimate my scope, even if it's a refractor? I read somewhere that refractore don't usually need to be collimated

Update: Just had a chance to try again last night, and, after reinstalling everything one more time and re-checking all the settings, it is now working!

Thanks for the help, everyone!

On 06/01/2023 at 11:34, alacant said:

Hi

You are trying to calibrate too far away from the equator - meridian intersection but anyway, most if not all the settings for your guiding arrangement are incorrect, except maybe the pixel size for the zwo.

I'd strongly recommend starting again. Make a new profile with the camera and mount attached and live with the mount guide speeds for RA and DEC both at 0.9. Take ALL the default values. Change nothing

Focus the guide camera and slew south around DEC zero and within say 30 minutes of the local meridian. Make certain the mount moves using PHD2's manual NSEW controls (watch the stars move on the display and/or listen for motors). Finally, slew N for a few moments. Now calibrate.

Hopefully that will get you calibrated.

Cheers and HTH

Thanks for the suggestions! I'll try again using default values and see if anything changes, although, besides changing the algorithm to PPEC and changing the step size, I don't think I've changed much.

Unfortunately I cannot image too close to the equator, and my mount is located in my garden, and it can only see a specific window in the sky.

I guess the biggest problem for me now would be waiting for a clear night.

1 hour ago, Clarkey said:

The download seems to suggest the scales are different, as per the comments from @scotty38.

"RA Guide Speed = 13.5 a-s/s, Dec Guide Speed = 1.5 a-s/s"

If you have them set the same, there is obviously something else amiss. From memory PHD2 does the Dec axis first which would explain the lack of movement at 1.5 arc secs per pixel.

EQMOD can be a bit quirky at times, so I would maybe try to re-enter the values again and see if this changes the values in PHD.

I did try changing the values in eqmod, as I later realized I had the RA set to 0.9 and the DEC to 0.1, but once I tried seeing if it worked, it was already too cloudy, unfortunately, and the reading were messed up, as per my last post yesterday night.

As soon as there's another clear night, I will try and see if it works

2 hours ago, newbie alert said:

This shows you're way out of polar alignment, and both axis are on a downward trend

could it just be the clouds messing up the readings?

I double checked my polar alignment both with the polar scope and the three-points polar alignment tool, and it was perfect within 2 seconds at most

Just now, woldsman said:

Try increasing the calibration steps to something like 1050 in advanced settings. 

It's already at 1350, automatically calculated...

Maye I should change the minimum move?

1 hour ago, Jonny_H said:

I had this issue the last time I used my set-up. Similar to you I hadn't used it for a while.

I Re-installed PHD2 and made sure all other drivers for other apps were updated and that seemed to do the trick.

Try reinstalling PHD2 first to see if that resolves the issue and go from there.

HTH,

Jonny

Thanks for the suggestion!

I actually wanted to try that first, but I didn't want to have to redo all my settings without being sure that it would fix the problem.
Since it did the trick for you, I will try and see if it works

edit: no candle. The graph still shows up as empty...

Actually! As I was writing this message, it started working! Hopefully it isn't just the clouds moving around... I'm doing another run and it still shows a dead graph... This is strange

43 minutes ago, windjammer said:

When you put it into manual guide mode does the scope move when you toggle E/W and N/S ?  If it does then check the pulse durations in manual mode are the same'ish as the pulse durations in calibrate mode. if manual mode  doesn't move the scope after twiddling pulse widths then  clearly something is not communicating: driver installations etc.  If you use ST4 then a scope on the control lines will show pulses - or not.  If its fancy ASCOM then beyond my pay grade, unfortunately.

Simon

The scope does move, and the cables are connected via Usb, so there shouldn't be any problem, as I could clearly see from the guide scope.

1 hour ago, scotty38 said:

I noticed the guide speeds were massively different for RA and Dec but I must admit I;ve not looked into what issue this would cause, if any

I initially started with 0.9 and 0.1, since I forgot to change both of them, but I later tried with both set to 0.9 and it made no difference whatsoever

1 hour ago, Clarkey said:

Assuming you are using Eqmod have you adjusted the pulse guiding rates? I think they default to 0.1 but need to be much higher. I think mine are set to 0.7.

yup, I have both set to 0.9

Hello everyone,

I just started using a new pc for my setup, and I installed everything copying the exact same settings from my old one.

Unfortunately, I seem to be unable to calibrate PHD2, since the program keeps telling me that the stars are not moving enough, and the history graph is showing nothing.

Could anyone help me figure out what is going wrong? Everything worked flawlessly with my old setup (altough, admittedly, I haven't had the chance to use it in a month, since the skies have been cloudy).

I am ataching 2 log files from tonight, just in case.

Thanks in advance!

Log 1.txt Log 2.txt

Thanks for the suggestions, everyone!

While I was looking into all your recommendations, the theft have been continuing (they keep robbing 2/3 houses every night, and the cops haven't managed to stop them yet), but their area of operations has moved a few cities away from mine, so it looks like things may be getting calmer... For now.

As I try to decide which option is the best for the long term, I have set up a temporary solution.

Since the pc connected to my mount is not accessible from outdoors, I have changed the windows sound for when a usb device is disconnected to a very loud siren noise, and I have set it to max volume and connected to a pair of Bluetooth speakers.

One speaker is indoors with me, while the other is outdoors.

Since, if they decide to rob me, I don't think they'll try to take everything away (the mount is quite heavy), they'll probably try to at least get away with the camera and scope. As soon as one of the usb drives gets disconnected, windows will start playing the siren noise at max volume, waking me up and, hopefully, scaring the robbers away.

I have already tested the system and it looks like the sound was loud enough for the neighbors to come to my house asking if everything was okay 😂

Let's hope this works in the interim!

On 20/12/2022 at 02:12, Budgie1 said:

Start from the Home Position - I notice you say you put it roughly in the Home Position, this can start you off with a built-in error which you'll carry through the whole alignment routine. So set your Home Position as accurately as possible (see this video for assistance) and put marks on the mount with a Sharpie so it's easy to find the Home Position again. 

Sorry to hijack the post, but I was wondering something.

Is starting from the home position really that important?

I initially set my home position with my mount perfectly aligned, pointing the scope straight forward (I did this like a couple of months ago).

Now, whenever I bring my scope outside, I don't really bother pointing my scope forward perfectly. I just start it wherever it is, usually pretty close to home position but not perfectly, polar align, and then platesolve, which usually fixes any error I could have made and properly recognizes the scop position relative to the home position.

Is this procedure wrong? 'Cause so far it hasn't caused me any problems

Hello everyone,

I usually set up my rig in the garden, right outside my window.

I have recently started using a laptop, but I tend to keep it between my blinds and the actual window, so that should be pretty safe.

I cannot say the same about my camera and mount, though...

While I have never been that scared of theft, recently there's a group of thieves going around and stealing from medium to big-sized homes, and my house fits the bill perfectly.

Does anyone here use any theft prevention methods?

I was maybe thinking of buying a scooter alarm, but I'm not sure how much help that would be...

10 hours ago, RolandKol said:

My suggestion would be, - do Not touch the camera tilt adjustment, check your focuser and all connectors you use first or "eyepiece clamp" you use in the focuser, - this may introduce slight tilt, especially once you place so many "mono toys" to hold.

RedCat looks like have quite solid focuser, so maybe you have not clamped it properly or any addaptor or even EFW introduced it. Disasable the optical train and assemble all back first, - double check.

In other words, check all other possible points of failure before adjusting the tilt of the camera.

And, to be honest, your FOV is large, so stars are quite small and the tilt is barely visible, - I would suggest to ignore it unless it goes out of control.

I have made another post on here showing some examples of what I assume to be tilt. I have tried taking everything apart and putting it back together, so I'm gonna shoot some exposures to see whether or not that has solved it, otherwise I'm going to try and move one piece at a time to see whether anything changes and make sure that it is actually tilt.

No luck today. It's currently 21 and the sky is super cloudy

@scotty38 @RolandKol @geeklee

I have proceeded, under the assumption that I have mistakenly taken all my lights at 30 offset instead of 2, proceeded to redo the whole thing. I shot all of my darks, flats, and dark flats with 200 gain and 30 offset, just to test whether the theory held any value.

You can see the results for yourselves in here: https://drive.google.com/drive/folders/1YliX_I4YkaKUSjJqnf061Lj7rF7Xnq1W?usp=sharing

I hastily made this combination just to see the results:

As you can see, while the problem seems to be mitigated, you can see that the patterns are still clearly visible in the background, although less, when compared to the previous results.

I'm not really sure what is going on, but I guess I'll just have to put the data aside for now and wait for another clear night to run some more tests. The weather forecast changed and it now says that it's going to be clear this coming Saturday, so I'll leave my scope out and shoot the same target (making sure that all my settings are correct this time), just to compare the final results.

(Not yet 100% sure on this, as I'd first like to run some tests on whether or not my camera has sensor tilt)

44 minutes ago, scotty38 said:

This is what I was trying to say about the driver differences. Swapping between these two won't necessarily keep the same offset settings and also explains why you can see the offset in the fits header of one but not the other. I know this because I've done exactly the same.

In the native driver NINA shows you the offset and you can change it there and then but with the ASCOM driver you can only see it and change it in the driver itself which you can do by clicking on the "gears" icon before connecting the camera.

I also think one of them defaults to 8 and the other defaults to 30. If you changd one of them to 2 then the other may have been 8 or 30 depending which you changed.......

I know what you mean!

What I was trying to say as well is that I did check those options and made sure they were correct (by clicking on the gear), but I changed the cables around, which may have reset them to default (although I cannot be sure).

While in the NINA app you can directly change the gain even with the Ascom driver, you are forced to use the cog to change the offset, so I am thinking that maybe I did actually shoot at 200 gain and default offset (I believe it was 30 as well).

Since I have plenty of things to try out, I'll test this as well tonight and see if it makes any difference.

Edit: Actually, I have the stats plugin installed, so I should have a json file with all the info pertaining to each shot I took!

4 minutes ago, RolandKol said:

Not sure about your cam, but once you connect ZWO to NINA, you have 2 options, to use ZWO native drivers or ASCOM ones, - they may behave a bit different, I have not tested.

I did initially use the ZWO driver, but later switched to the Ascom one since I was having troubles with PHD picking my main cam as a guide.

As far as I know, though, I should have used the ascom driver for both lights and flats in this imaging session (not sure about the darks, but I am sure that those had the right settings).

4 hours ago, geeklee said:

EDIT: I've had a look at the files and compared to my own.

Two observations:

• The Master Flat is underexposed. It looks fine but typically aim to get the histogram further to the right.
• I think the Master Dark and Dark Flats could be causing the issue.  As I mentioned below, did you mean offset "2" when you typed that above?  

I looked out a 90s Master Dark I had.  Gain 120 and Offset 30.  So the defaults.  I had a play with calibration and got a result on your Ha with no discernible pattern (except the amp glow where we mismatched more clearly).  The pattern would have been there with a strong enough stretch as our calibration frames mismatched but the point was it wasn't overcorrecting massively. Perhaps your lights were offset 30 or higher than 2 anyway.

Lee

I'll answer the question regarding offset first:

If you see my first comments on this thread, pluse the first piint of Vlaiv's reply, you can see why my offset is so low.

Keeping gain at 200 and offset at 2 allows me to have the minimum pixel value slightly above 0 when integrating some bias frames.

As for the flats, I'm not really sure how they could be underexposed, as I took them with NINA's flat wizard and made sure to keep the histogram at 50%.

As I mentioned previously, I'll try retaking ALL the calibration subs tonight and see if I can get everything to work. Maybe I changed some value by mistake without realizing...

I tried checking in pixinsight but, while it looks like I can see the gain value clearly for my lights (it's 200), the offset value is not using the same unit of measure as NINA, so I have no clue what the value presented to me by pixinsight corresponds to in NINA...

13 hours ago, scotty38 said:

Yes I did mean camera offset so if they're the same that's fine. I looked at the headers and it seems that different drivers were used as the offset only shows up on the lights. I recall this from the NINA native versus ascom drivers when I had my 294mc and it bit me as the defaults for offset were different. 

EDIT - I'd like to read where you saw offset didn't matter being different as that's a new one on me and from what I've seen it very much matters.

Huh, this is strange. I thought I took them both with the same driver, but oh well. I tried opening them in pixinsight but the offset value for the lights is not using the same unit of measure as NINA, so I'm cannot confirm that it's 2, but it should be.

As for the other question, I'm not really sure where I read that, but it was a post going around the internet. Since my gain was so high, I was looking into whether I could take my lights and flats at a different gain and offset value to be able to get my RGB flats decently, as my sky flats were too bright.

For the new ones I will use tonight, I made sure to use the same exact settings as my lights, but I'll reconfirm it later when I get home.

2 hours ago, Gumminess8083 said:

I do use multiple stacked subs, usually I take 50 calibration frames per type (you can find a folder with the stacked masters at the same link). I only shared one per type since I am running out of space on my GDrive...

As for the flat frames duration, I was taking sky subs and had a hard time taking them, as the sky was too bright. I did try retaking them today indoors using a tablet, but the patterns were still present (and the light was too dim, so I had a hard time getting any flat frame with an exposure time below 30 seconds at 200 gain).

Since I've tried everything, I might as well redo the whole procedure using a new set of flats with a longer exposure time. I have moved the optical train, so they won't account for any tilt or dust bunny, but they'll at least fix the artifacts, hopefully...

I'll also try stacking some uncalibrated light subs, just to see what comes of it.


Update: I tried stacking some uncalibrated lights, and the patterns seems to be showing there as well, so the problem may really lie with my underexposed flats... I'll try taking some more and run some tests.

Update 2: I tried taking some new flats using the flat wizard and my tablet. S at 3.87 seconds, H at 10.46 seconds, and O at 5.87 seconds. I'll try stacking them tomorrow after work and see what comes of it.

(Not sure why this update was posted as a separate comment instead of an edit, but oh well...)

19 minutes ago, scotty38 said:

Are you sure they're all using the same offset?

If you mean camera offset, then yes, 200 gain and 2 offset (although I read somewhere that it's not necessary for flat frames to have the exact same gain and offset as the lights). If you mean filter focus offset, then I haven't bothered too much with that, since the filters are supposed to be parafocal.