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#1 Hook

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Posted 22 July 2021 - 07:46 AM

Just a quick question.

 

Does PHD2 keep the image from the ccd camera as the camera sees it? or does it flip the image?

 

I am trying to work out how to keep my canon camera to match the image from the guide ccd camera. If I use sharpcap I can get the 2 images to match, in raw mode, (not in rgb so I can flip it). If I use the altair capture software it flips the ccd straight away, as soon as I connect. So which of those 2 programes, (altait/sharpcap), is showing me the image that PHD2 would show?

 

Thanks



#2 terrypaula

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Posted 22 July 2021 - 11:03 AM

From what I know the image should be upside down and backwards.



#3 AhBok

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Posted 22 July 2021 - 02:41 PM

Just curious why you want to keep the images the same since it makes no difference in guiding accuracy?

#4 Hook

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Posted 22 July 2021 - 02:47 PM

From what I know the image should be upside down and backwards.

I should have mentioned that the finder/guide scope is a 50/190, so quite small. I would have thought the same as you say, however, the other 2 capture software, (sharpcap/altair), are the opposite of each other. One gives the view as upside down, the other the right way up vertically and horizontally. They both have flip choice, but I am giving the examples as the software in standard mode...without flip on.

 

I am hoping tonight will be clear enough to find out. I have both set up as if using sharpcap, so image is right way up both axis.

Interesting how these different software makers choose to show the image in opposing directions. All I need now is to find out if PHD2 chooses 1 or the other. Knowing my luck the image will be opposite to the canon, and PHD2 does not have a flip option.

 

Only reason I want to know is so that I can move the system for star alignment according to the guide camera, then take a quick snap with the canon to confirm. I have spent hours getting the 2 to be dead centre on an image. I don't touch the canon BTW, I have it on a remote to the canon PC software.



#5 kathyastro

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Posted 22 July 2021 - 02:51 PM

There is nothing preventing you from rotating the guide scope in its rings to match the orientation of the imaging camera.  PHD2 doesn't know or care which way is up.  It just shows the data the way it comes from the guide camera.  It figures out the actual orientation from the calibration run.



#6 Hook

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Posted 22 July 2021 - 02:51 PM

Just curious why you want to keep the images the same since it makes no difference in guiding accuracy?

It's not for guiding accuracy, just for star alignment. I want the star to be dead centre of the canon.....and I have great difficulty trying to do that if both images are reversed to each other. I get all confused with moving it in one direction to centre and then find out I should have moved the other way to centre it in the canon.


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#7 Hook

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Posted 22 July 2021 - 02:56 PM

There is nothing preventing you from rotating the guide scope in its rings to match the orientation of the imaging camera.  PHD2 doesn't know or care which way is up.  It just shows the data the way it comes from the guide camera.  It figures out the actual orientation from the calibration run.

Yes, that is fine if it's just a case of rotating the ccd. In the case of the 2 pieces of software I wrote about, rotating the ccd would make no difference if the image is always upside down and left is right on the canon.

I understand that the PHD2 does not worry about orientation, it's purely for getting stars centred on the canon........due to my frustration with moving in reverse mode and left is right mode.



#8 dghent

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Posted 22 July 2021 - 02:56 PM

But it doesn't matter. For your centering wants, does your imaging software have a centering feature that uses plate solving to take care of that?



#9 kathyastro

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Posted 22 July 2021 - 03:33 PM

rotating the ccd would make no difference if the image is always upside down and left is right on the canon.

Rotating the camera 180 degrees will rotate the image 180 degrees.

 

Are you saying that one of the two images is mirror-reversed?  No camera does this by itself.  There must be an option selected somewhere in software that does this.  All you have to do is find that option and un-select it.



#10 bobzeq25

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Posted 22 July 2021 - 04:50 PM

If this is about getting pointed to where you want to image, you're really making it harder than you have to.  What most all of us do i9s platesolving.  Easier to do than to say.

 

I GOTO my target, not caring if it's in the frame or not.  Shoot a short sub, all I need is some stars.  Load it into PlateSolve 2, with my targets RA and DEC, and the field of view   Hit "solve".  PS2 tells me exactly (understatement) where I'm pointed.  I know where I want to be, and I correct.

 

You need the free PS2 and either one of the two associated catalogs.  A fits or a jpg.  You can practice on an image in daytime.


Edited by bobzeq25, 22 July 2021 - 04:51 PM.


#11 Hook

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Posted 23 July 2021 - 03:28 AM

Rotating the camera 180 degrees will rotate the image 180 degrees.

 

Are you saying that one of the two images is mirror-reversed?  No camera does this by itself.  There must be an option selected somewhere in software that does this.  All you have to do is find that option and un-select it.

Yes Kathy, that is what is happening. I know it is not the camera, but the software itself. Both software have a flip option, but which one of them is showing the true image? Neither have the flip "on", so one of them chooses it as "normal". Too much cloud last night to discover.



#12 Hook

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Posted 23 July 2021 - 03:59 AM

If this is about getting pointed to where you want to image, you're really making it harder than you have to.  What most all of us do i9s platesolving.  Easier to do than to say.

 

I GOTO my target, not caring if it's in the frame or not.  Shoot a short sub, all I need is some stars.  Load it into PlateSolve 2, with my targets RA and DEC, and the field of view   Hit "solve".  PS2 tells me exactly (understatement) where I'm pointed.  I know where I want to be, and I correct.

 

You need the free PS2 and either one of the two associated catalogs.  A fits or a jpg.  You can practice on an image in daytime.

Seems to me that plate solving takes just as long as me looking at a photo I take with the canon. This is why I want to do it the way I describe. I can at least learn the sky by looking at my photo's, and taking a photo it gets uploaded immediately into my pc, and I am looking at it within 3 seconds of taking it.

PHD2 will not work during the day for images, I tried that and all I get is a white screen. The minimum exposure is 0.01s, and with that in place and gain off, it is still a white screen.....but just asking myself, "do I need to run the ascom eqmod to engage the camera"? I wouldn't have thought so as it is just an image......

 

If I am unsure of my location I can use Nova, (that Kathy advised...thanks Kathy). Once I'm more accustomed with the sky I will be using Nova less.

 

In all honesty, there is a plethora of software out there for doing as we want. I do not want my PC stuffed full of software, (which all requires a learning curve...and some of it lengthy). I am happy enough using a guide camera, PHD2, Stellarium, and my canon hooked up to the canon software. I look at some videos on youtube from "experts", and they are in conservatories, have the latest mounts, about 5 monitors, 3-5 PC's/laptops, and when they show their screen......countless pieces of software.

The majority of us do not have that and have neither the finances or time to get it and learn it.

 

Most of us want a simple set-up that works to the way we want. Some want to learn the sky, some do not and just want good photo's.

 

You have that "long-haired" bloke on youtube that does apt......he's brilliant. He takes better photo's with an i-phone on a piece of wood, using a straw to polar align and manually moving the mount, (to which the wood is clamped to!)...........and way better than mine. He needs no plate solving or exotic software. What he does have is knowledge.



#13 michael8554

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Posted 23 July 2021 - 06:28 AM

Depending on the type of imaging OTA - Newtonian, SCT, Refractor, and any FR or Flattener - the image on the Canon could be laterally reversed and inverted, or permutations of those.

 

The guidescope image will probably just be inverted, you can rotate the guidecam 180 degrees if it helps you.

 

Best you can do is try all your flip options, and eventually note which way stars move in each camera when you make small north and west slews, and keep a note.

 

As others have said, PHD2 doesn't care which orientation the guidecam is in, PHD2 Cal sorts that out.



#14 Hook

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Posted 24 July 2021 - 06:42 AM

So I got my answers last night.

 

The image in PHD2 is in the same orientation as a dslr connected to the main scope, (same as sharpcap). My hours of getting both images lined up and centred during the day paid dividends....they were both precisely aligned.

 

Now the process of star alignment was so easy. I decided to use the Elephants trunk nebula as my target, so I picked out 3 stars that formed a triangle around that location. It was easy to align, take a pic with the canon to confirm centre, and move to the next. I did of course do calibration first by going to the solar meridian. Once I had those 3 stars aligned and into eqmod, I swung over to the ET nebula, picked out a star and started guiding. The guiding was like looking at a flat line on the graph, I couldn't have asked for better.

 

Unfortunately cloud started coming over around midnight, but I took a few snaps. Now I need a flattener!..the pics were so good I could obviously see the star elongation around the edges, there's always something!

 

So for anyone reading this, and has a similar set-up, this process works perfectly. I am also getting used to knowing the star I want to align with, and I picked on a star that was not the brightest but the pattern of the surrounding stars was fairly easy to work out. I needed no plate solving, no finding my location via nova, and working out the orientation of the ET nebula was easy thanks to the Garnet star.

 

I used a bit of tape on each camera to mark the same orientation, as I will be orientating the canon at some stage to "frame up" an image.

 

The whole process from Polar alignment to taking pics of the target took about 20 mins, not much if you consider that the final result is the one you want.

 

Thanks all, and I will now be posting about what flattener to get.




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