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Image of M42 & M43 from Chile
#1
Here's an image taken using iTelescope T71 in Chile on 2023 Feb 22:     

It's a stack of 30 second LRGB exposures processed in Astro Pixel Processor (APP).

Phil S.
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#2
That's very nice Phil!

Out of curiosity, why did you use such short sub exposures? Was the center ever exposed?
Clear skies,
Greg
Head Dude at Skyhound
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#3
I noticed that T71 is an f/2.8 system & I didn't want to overexpose the central portions of the nebula. I planned to take 15 30 sec subs for each channel, but only got 9 blue, 11 green & 12 red & lum before the reservation ended. Many of the stars were saturated.

It still looks pretty decent even if it is upside down  Wink.

Phil S.
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#4
I hate having to ask a question like this, because it can be really embarrassing for everyone involved. But I have to be aware of whats going on with users in order to have the best product, but I never get enough feedback these days. People just don't seem to think like that anymore.

SkyTools can tell you if it will saturate, and which stars will too. It sounds like you aren't really using it. How come?
Clear skies,
Greg
Head Dude at Skyhound
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#5
This imaging run was a snap decision. There was a gap in the reservations for T71 & I decided to go for M42. I did check it out using ST4i with the Camera View. That's were I noticed that many stars would saturate. The reservation time put M42 at ~45° above the horizon at the start of exposures. The Scheduler wouldn't have liked that.

I've had trouble getting my reservations on the iTelescopes & using ST4i to set up a Plan takes me a while. I've had folks grab a scope while I was preparing a Plan before & didn't want to miss this opportunity.

For this run, I logged onto T71 & created the Plan right on the scope. Then grabbed the reservation. I only got 44 of the planned 60 images, but since they were in 5 groups of 12 (3x3x3x3), I got some for each filter. Perhaps ST4i needs a flag to collect images in that mode instead of taking all images through one filter at a time. 

This was a case where I didn't have time to go through the ST4i workflow & coordinate with the iTelescope reservation system.

Does this answer you questions?

Phil S.
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#6
(2023-02-25, 01:46 AM)PMSchu Wrote: I've had trouble getting my reservations on the iTelescopes & using ST4i to set up a Plan takes me a while. I've had folks grab a scope while I was preparing a Plan before & didn't want to miss this opportunity.

What I do is make the reservation first, then add the plan later. But you can't do that, you say? You used to be able to do that without attaching a plan. In fact, you used to be able to make a reservation and then show up and run things more or less manually. Anyhow, the trick is to always have a plan available for that scope. Any plan. I attach that one temporarily, and then when I have a new one ready I open the reservation and attach the final one.

Thanks for your explanation. I know how one can be in a hurry. Sometimes opening the Exposure Calculator can give you quick answers. My guess is that longer exposure may have had a better result. That's the way it usually goes under dark skies. But I haven't used T71 much.
Clear skies,
Greg
Head Dude at Skyhound
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#7
(2023-02-25, 04:04 AM)theskyhound Wrote:
(2023-02-25, 01:46 AM)PMSchu Wrote: I've had trouble getting my reservations on the iTelescopes & using ST4i to set up a Plan takes me a while. I've had folks grab a scope while I was preparing a Plan before & didn't want to miss this opportunity.

What I do is make the reservation first, then add the plan later. But you can't do that, you say? You used to be able to do that without attaching a plan. In fact, you used to be able to make a reservation and then show up and run things more or less manually. Anyhow, the trick is to always have a plan available for that scope. Any plan. I attach that one temporarily, and then when I have a new one ready I open the reservation and attach the final one.

Thanks for your explanation. I know how one can be in a hurry. Sometimes opening the Exposure Calculator can give you quick answers. My guess is that longer exposure may have had a better result. That's the way it usually goes under dark skies. But I haven't used T71 much.
I hadn't thought of using a dummy plan to satisfy the reservation system. Thanks. 

I'm in the Eastern time zone & using the iTelescopes is usually a last minute thought before I turn off the computer.

T71 is an f/2.8 system so I expected it to record images quickly. It did pretty well with 30 sec images even with only 270 seconds of blue capture time. The mount's also allowed to track down to 0°! Much of that's probably due to the quality of the atmosphere at the site. I shoehorned the reservation between two other reservations as M42 was setting, so I'm happy to get this result.

Phil S.
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#8
"T71 is an f/2.8 system so I expected it to record images quickly. It did pretty well with 30 sec images even with only 270 seconds of blue capture time. The mount's also allowed to track down to 0°! Much of that's probably due to the quality of the atmosphere at the site. I shoehorned the reservation between two other reservations as M42 was setting, so I'm happy to get this result."

Phil, no offense, but when I read something like "its an f/2.8 system" I want to bang my head on the wall. I literally wrote SkyTools so that such rules of thumb would be unnecessary.
Clear skies,
Greg
Head Dude at Skyhound
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