Hi All,
I posted this initially under DSLRs and CCDs but didn't get any response so trying under ekos - hope no one finds that annoying.

I've been using ekos mainly connected to my Nikon D7500 connected to RPi running stellarmate OS remotely from an M1 Macmini with manual lenses: Nikkor 135mm, nikkor 200mm or 127mm Orrin skyview pro Mak-Cas. While captures are working well I noticed a couple of things that I hope I could get help with.

1) exposure times for the DSLR (at least my Nikon d7500) don't coincide with the DSLR presets. For the most part they do but it skips from 1/1000 to 1/8000. I do see the presets in a very nice dropdown menu in the Indi control panel for my Nikon though. It wouldn't be an issue but if I just enter a random exposure time in the exposure box the metadata for the picture shows the closest preset value to the exposure I entered and not the exposure value I entered. I guess I would have to know the decimal value for all the presets so I can be confident that the exposure times are accurate. Am I missing something?

2) live video opens the player window but I just see a black screen with exposure set to .1000s and no framerate

3) Sensor resolution changes between lights and flats. My cameras resolution is listed as 5600x3733. Once it starts taking fits captures it changes to 5600x3728 and then when doing flats in the same session it changes 5600x3712. Siril doesn’t want to preprocess because the resolution is different. What am I doing wrong here??

Can someone please advise?

Thank you,
Eli

Hello Eli,
Knowing exactly which problem you face with which SLR and with which lens would help.
Else, we could only speculate.
Rgrds,

Hi,

My camera is listed in the post but perhaps I could have emphasized it better:

Nikon D7500 connected to RPi running stellarmate OS remotely from an M1 Macmini with manual lenses: Nikkor 135mm, nikkor 200mm or 127mm Orrin skyview pro Mak-Cas

Hope that helps.
Thank you,
Eli

my original post has been edited to provide some missing information.

Apologies for the confusion.

Thank you,
Eli

You wrote "exposure times for the DSLR (at least my Nikon d7500)", which made me think that more than one camera could be involved.
I am casually using Nikon DSLRs (D4s, D700 and 1v1), so I might be able to help.
Well, I just remembered something about sensors resolution. On the dedicated site , one can see two different vertical values.
The first is related to the maximal image resolution, the second to the sensor resolution.
Update indi with the first, and see if it gets better.
For exposure, let me some more time.
Rgrds,
J.-Luc

Hi Jean-Luc,

Thank you for your reply and helpful suggestion. So some progress. I have tried this with two different types of connections:

1)Running kstars/ekos on M1 Macmini with remote RPi connected to my equipment running Indi through stellarmate OS (this is my normal method)
2)Running kstars/ekos and having all my equipment connected directly to an intel MacBook Pro with a remote connection via remote desktop on M1 Macmini

Using setup 1, ekos is able to populate the maximal image resolution and pixel pitch directly from the driver. Sometimes not at first but if I disconnect the DSLR driver and then reconnect it works without fail. Then when I take a preview capture the resolution automatically changes to the sensor resolution. But the sensor resolution is different if the output selected is a fits file or native file. I have not seen a way to force the resolution one way or the other.

Using setup 2, I get a popup to enter the sensor resolution and pixel pitch and so I entered the sensor resolution. It seems that it is stable wether I capture in fits or native.

Thinking about it - it is completely possible that when I first dowloaded kstars a few years ago I entered the resolution values but erroneously used the maximal image resolution rather than sensor resolution. Anyway I can fix that?

As for live view I can't get it to work with either setup. So still having problems there.

what do you think?

Thanks again,
Eli

Hello,
Very - too much - busy today with shower problems.
I just took a few minutes to make some screenshots which, I hope, will help you.
These are the places where you must type the relevant informations about your SLR. Took the D700 which was the nearest, so adapt to yours.
You need to set values in indi tabs and hopefully they will be updated in ekos.
Any setting can be modified afterwards (unless Murphy comes there...), so, yes, if the vres you set is not the correct one, it can be modified in tabs 4 and 5.
Be aware, too, to set Format to RAW and Encode to Native.
Then, in Ekos, each time you create a sequence check that the values were not modified (Murphy ?).
Rgrds,

Hello,
About your shutter speed settings, do you mean that if you set 1.125 into Ekos Exposure field, it will not expose this value ?
I did not think about this before, as I mainly use exposure times over 10 sconds.
Rgrds,

Hello Jean-Luc,

Yes, that has been my experience. If it is not a preset exposure it will show in the metadata the closest preset exposure. So in your example if I set exposure to 1.125 sec the metadata will show 1 sec. But really the issue for me has been for exposure between .001 and .000125 - in the exposure box if I click the up and down arrows the values change to preset values but for some reason it skips from 1/1000 to 1/8000 (.001 to .000125 sec) where in reality there are many preset values in-between. I know it's not a common case to use such short exposures it has only come up for me when I was testing my camera sensor using different exposures for flats using my led flat panel. right now I can't test this again because I redownloaded the current 3.6.6 version of kstars for Mac and as you know there is some problem where we are getting an error that the file is damaged. unless you know where I can download an older version of kstars I'm stuck impatiently waiting for issue to be fixed. Maybe you know of an older version of starts 3.6.5 that I can download - I haven't been able to find a download for that anywhere.

I will also adjust the control panel settings as you mentioned in your previous message.

Thank you so much for taking the time looking into my issue. I really appreciate it.

Thank you,
Eli

Hello Eli,
There was a typo in my previous post : I meant 0.125 ; 1.125 is not an actual exposure value, so maybe is it logical that it choses 1 sec, since the next upper value is 1.3.
As 1.125-1=0.125 and 1.3-1.125=0.175, 0.175>0.125 so the nearest for 1.125 actually is 1.
What would be interesting would be to test with 0.77 (1/1.3), 0.625 (1/1.6), 0.5, 0.4 and 0.125.
About the values displayed with the arrows, I am facing the exact same behaviour with my ZWO too : I have to set the exact value with the keyboard else it skips a large range of them.
I had started reading the documentation, but ran into problems and stopped.
My biggest problem is that there is no eyepiece on the ZWO, so I cannot point the objects like I did with my SLR, so most of the time it takes me over 1 hour to be ready, where I got it in less than 1 minute before.

Hello,
So, I tested a few minutes ago with my D4s.
I created two sequences with tasks from 5s to 1/8000s, one with 2s delay between takes, the second with no delay.
On my first attempt, the transfer was set to RAM, and if worked as long as exposure were >1/30s (0.033s).
As soon as it reached this point, it began failing.
So, I stopped it and modified the settings as shown on my screenshots. And I restarted the sequence.
It achieved flawlessly, althought it seems obvious to me that some extra time was added to the 2s delay I had set.
This was confirmed by the second batch, which was supposed to chain the takes with no delay, but for which I could count up to 3 seconds from the end of a take to the beginning of the next one.
Unlike the first aborted attempt, the pictures were now correctly recorded to the SLR SD-card, but also on the PI's one. That ought not have been.
The good new is that the exposures as reported in the fits headers are correct - ie. 0.033s in kstars displays 1/30s on the SLR and 0.033 in the fits header. However, the values are truncated in the pictures name, so for many exposure times it will display the same value.
OK, I think I have found why the extra delay and the dual saving : I might have to set to Local instead of Distant in kstars capture tab. I am going to check this later.
If you use the sequences that I attached, don't forget to edit them and modify this as described.
For the other settings, as shown in Indi tabs, I think they are quite good.
Have fun,
J.-Luc

New tests that confirm that the values must match those known by the camera, as you can see below.
First, it browses the list of known values and tries to find the nearest :It has found something that seems to match :It sets the value according to the match found in the list :Value is validated :Exposure can begin :So, yes, you must enter the exact valuescorresponding to the ones present in the FW of the SLR.
What still is not good, is that extra delay it systematically adds to each take, and the fact that it also saves to the computer even if I tell it to save to SLR SD-card.
Also, the field in capture tab ought to allow three more digits, and when using the arrows it ought to browse the values in the index find the closest.
Time to a request feature and a bug report.
Rgrds,