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What am I doing wrong here?


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Hey folks.

I am very much a beginner at astrophotography, I had a nikon D800E and I bought an ioptron Sky tracker about two years ago with which I got a satisfying picture of Andromeda, although to be honest someone else did the processing.

I wanted to move forward a bit and over the last couple of years I have acquired a skywatcher NEQ6 and what I believe is an altair 102mm refractor. I recently picked up a set of Baader Hyperion eyepieces and thought I was in a position to try and get a decent shot of mars. attached is a pic of the equipment as its usually set up. capture and focus is not the issue, I dont think, trouble is I dont know what the root problem is!

so, I have the scope and the camera all set up, I am tracking my target, I am recording ten minutes or so of video which on the D800 is in MOV format.

I have bajillions of tools available to me, I have an adobe licence with premiere pro and photoshop, I am an IT guy, I can get software, but the captured image of mars is just so damn small and the frame is so huge.

I am watching youtube videos like this one: https://www.youtube.com/watch?v=FQagPJ8pM7Y and the image in the viewfinder is massive, all the tutorials on post processing in registax or autostakkert have large, clear images of the targets. I have a tiny group of  about 16 pixels.

I am capturing video at  1280/720 60FPS but even with the magnification I have from the 5mm eyepiece, I have literally nothing to work with.

The raw MOV file is here https://www.dropbox.com/s/7yw522qs3h5eda9/_REM6225.MOV?dl=0

What can I do to improve the workflow? Currently its capture -> registax -> nothing. it all dies because the image is too small to put any align points on. its just a single dot.

 

 

 

scope_camera_rig.jpg

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The youtube video aside, I have looked at the image produced from stacking and its eight pixels wide, is this normal? I have attached it, looks like it's out of focus to be honest but I can't get over how small it is!

 

_REM6225_pipp.png

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10 minutes ago, irtuk said:

The youtube video aside, I have looked at the image produced from stacking and its eight pixels wide, is this normal? I have attached it, looks like it's out of focus to be honest but I can't get over how small it is!

 

_REM6225_pipp.png

Must be some mix up there - The attached image is 200x200px.

Edit: Oh, you mean Mars is 8px wide. 200x200px is very small for a final image.
I guess that's a pretty heavy crop but, still, that doesn't make Mars any bigger.  😛


Bolting your DSLR straight to the scope is called prime focus. I'm sure someone could do fancy maths but let's, for arguments sake, say that's like looking through a 25mm eyepiece.
You probably want something more like looking through a 10mm or 4mm, for example, so you'll want to use a barlow, eyepiece projection, or a longer focal length scope, or some combination of the above.

I don't have a lot of experience but I did recently grab an eyepiece projection adapter and give it a quick test run on Mars.
Can't remember which eyepiece I used for this - It was just for testing and getting to know the gear, but I guess this is closer to what you'd imagined?

 

mars.png

Edited by Steenamaroo
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Sorry I meant the planet, not the whole image, but yes, that was more what I was imagining. I have a Baader Hyperion 5mm eyepiece attached to the DSLR, both optical sections of the eyepiece are in place, so its a proper 5mm not the 15mm or so you get if you remove the 1.25 inch nosepiece from it.

 

Looking on the astronomytools it looks like adding a 4x barlow will make a huge difference, guess I just fancied a bit of advice in case theres something fundamental I am doing wrong in either the capture or the processing.

 

Ed.

 

astronomy_tools_fov (2).png

Edited by irtuk
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Actually.... if I stick a 5x barlow into the mix will that take the scope over it's maximum magnification? I am reading that to calculate the maximum usable magnification, before things start getting worse, its aperture x 2 so, on the 102mm starwave that's going to be 204x magnification. Sticking a 5x in would take it up to 572 times magnification which I would imagine is going to give very poor results.

Would this necessarily matter though? for imaging?

Edited by irtuk
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so, a cheapish 5x barlow arrived today, wife vetoed the Baader plane flattening 4x-8x rare exotic glass one I nearly went for, quite an improvement I think, although I can't explain optically why this is bigger, which is annoying! This is processed in autosakkert.

 

 

20201110201158302_lapl5_ap13_Drizzle15.jpg

 

Its also using a different camera, an altair astro GPCAM 224C I bought a couple of years back. the sensor is smaller, the pixels are smaller, so I can sort of get why a small image would cover more of a small sensor relative to the gigantic Nikon D800 35mm sensor...

 

Is it now possible to get a male <> male thread adapter for an eyepiece and do eyepiece projection onto the Altair camera...?

Edited by irtuk
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