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Real newbie Jupiter shot - serious help wanted


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Few newbie questions I'm afraid, although may make you laugh at just how newbie!  Sorry for the length of the post and number of questions (esp if this is against forum rules / etiquette), but couldn't see point of submitting multiple posts and people on the forum seem adept enough
to handle multiple questions.



I got my Skywatcher Explorer 130P Autotrak last year for my birthday.  I already had a Nikon D7000 DLSR and have recently purchased a T-ring adapter, which I use with the 2x Barlow that came with my Skywatcher and a Bhatinov mask as I dont seem to be light fingered enough on the Skywatcher's focussing knob (or my eyesight isn't what it used to be!).


On April 15th with clear skies I took the telescope out for an image of a full moon.  I lined up the finderscope on the brightest star I could see and attached the Bhatinov and began to focus.  Soon realising the point of light seemed more like a disc, I swapped the 25mm eyepiece for my 10mm and realised from the discs pattern I must have been looking at Jupiter - I did say I was a newbie!


Suddenly more interested in imaging Jupiter (even through the sky was relatively bright, Jupiter seemed bright enough), I attached my Nikon and after focussing some more through the cameras viewfinder, I took a few minutes of video (well a couple of them).  I then used Quicktime Pro to extract the (BMP) images from the Nikons H.264 .MOV file and used c.500 of these for Registax.  Used all default settings as most tutorials I can find for Registax dont go into much detail.  I did use the De-ringing setting, as this seemed obvious for the first problem I was having.  Then exported to Photoshop for cropping.  Although my image is very poor compared to others on this site, I have a tiny glow of pride and I am looking to improve - therefore uploaded image to my gallery for information, not gasps of awe!


jupiter



My questions are as follows (again apologies for the number)


1) Focussing

i) With Bhatinov mask attached, moving my eye around in the eyepiece moves the Bhatinov diffraction lines, so do I just have to get everything well centred and aligned (star image and my eye) to ensure good focus?


ii) When using the Bhatinov with my D7000 attached am I OK focusing through the viewfinder, or would it be better to use a laptop as this sees exactly what the sensor does?


2) Imaging

Any tips on improving my imaging technique (without changing the kit)?  For example, I have triggertrap cable for my Nikon / iPhone, so I could take rapid multiple shots very easily.  Would the extra resolution of the cameras RAW images produce better shots for Registax, or would the vibrations from the camera shutter outweight any benefit of the extra resolution?


Or am I kidding myself that the H.264 DSLR video will do anything near as good as a converted webcam (let alone a CCD).


3) Magnification

How do I get better magnification at reasonable cost?  I would love to try for a better image of Jupiter, and it seems bright enough to handle more magnification with my current set-up.  Was thinking get / make a converted webcam (which will allow eyepiece magnification aswell as barlow) and/or just use a stronger barlow?


4) Tracking

The set-up manual for the Skywatcher says you can set-up auto-tracking for stars, moon and planets, but there are no settings for changing between these objects and surely they all need to track different planes and rates of movement?  Or am I misunderstanding some of the basics?


OK, so I could have just asked "how do I get a better image without spending a fortune", although I thought this too open-ended and may have missed the points I wanted help with.


Thanks greatly in advance for any help!

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Thrre a few issues I can help you with first your image looks a bit over exposed I use a ccd imager so I cant help you with your dslr but I think with a dslr you take single shots then layer them together .I don't know why they have different tracking options on your mount because all the settings do the same . I know you can plug in a goto handset in your scope this might be better for you becauee its more flexible .your image is a good image for a first attempt just a bit over exposed .if you want to go down the video route I would try different processing software and see what works for you most people now process with astrostakkert then drop it into registax to adjust the wavelets

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has your 130p got rack n pinion focus? i no my old explorer 130 did i attached a peg to the ajustment knobs then it allowes u finer adjustment because 5mm movement of the end of the peg is equal 2 smaller movement of the wheel it's self i also use 2x barlow wir t-ring thread on my camera but then slip in anothe 2x barlow or even 3x barlow with lil to no problems

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Thanks for the tips, will try them all!

Sounds like a peg screwed into the focusser will give more control, a 3x Barlow will help with magnification and will look at astrostakkert also for processing vids.

Thanks all who fed back!

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What mode did you use on your DSLR? One common approach is to use movie crop mode which artificially applies'zoom' and helps with image scale. Most AP is done using Canon due to greater access to appropriate software control but there are Nikon users on SGL who may advise you.

As an example here is my first Jupiter taken last month using this mode. Keep at it, it took me a while to learn the necessary techniques.post-35542-0-00723300-1397999274.jpg

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Impressive image!

I used the standard D-Movie mode on the Nikon D7000.  I have been looking at trying to get more options / setting in this mode, but they seem fairly limited on the D7000.  I had also been looking at comments about Canon and Nikon hacks for movies, as I was trying to see if I could update the firmware (like Magic Lantern for the Canon) to get better frame rates or zoom, but have failed to uncover anything exciting...

I am therefore thinking of trying multiple RAW exposures, but think the shutter may add too much vibration - will have to try it and see.

Pity I didn't already have a Canon...

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think the shutter may add too much vibration - will have to try it and see.

 I'm assuming you're using a cable release. Does your camera have a mirror lock? It's a good way to reduce vibration when taking individual frames.

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Not bad for a first attempt. Slightly out of focus and over-exposed but the belts are clearly visible so almost there. Could you not feed the MOV video file directly into stacking software such as AS2 or Registax. Not sure if this will work so you might need to find something to convert it to an AVI file first. Has anyone else had any success with .mov files?

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I use a Canon and software called Backyard EOS (BYE) which allows full camera control using your laptop so you can take AVIs or stills. I understand that the BYE people have put together a Backyard Nikon so you might want to look into that.

Peter

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Not bad for a first attempt. Slightly out of focus and over-exposed but the belts are clearly visible so almost there. Could you not feed the MOV video file directly into stacking software such as AS2 or Registax. Not sure if this will work so you might need to find something to convert it to an AVI file first. Has anyone else had any success with .mov files?

I use a Canon 600D and PIPP to convert MOV to AVI (also to crop as much dead space from the video as possible).

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Just looked at this image again on a decent sized screen and it looks like you have also captured 2 moons. If you check on a program like Stellarium and set it to the time you took the shots it will tell you which ones they are. You might have to flip the image to get the orientation correct. It is only slightly out of focus otherwise the moons would be clearly visible.

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Not bad for a first attempt. Slightly out of focus and over-exposed but the belts are clearly visible so almost there. Could you not feed the MOV video file directly into stacking software such as AS2 or Registax. Not sure if this will work so you might need to find something to convert it to an AVI file first. Has anyone else had any success with .mov files?

Should be able to control exposure easily in movie mode - just didn't try hard enough before rushing inside to process my first capture!

Registax wont take MOVs, although could pass through conversion software like Gomtuu says like PIPP or Virtual Dub.  My only concern was these programs may be producing more conversion aberrations than a BMP image sequence and re-loading into Registax.  Would prefer to capture uncompressed AVIs, although sounds like that is the preserve of Canon owners with Magic Lantern firmware :-(

I use a Canon and software called Backyard EOS (BYE) which allows full camera control using your laptop so you can take AVIs or stills. I understand that the BYE people have put together a Backyard Nikon so you might want to look into that.

Peter

Looked but couldn't find anything on their site - in fact the only mentions of Backyard Nikon were on forums, so sounds like it's "still in the making..."  

I did look for Nikon software and hacks, but Canon seem to be miles ahead in this regard.  The only Nikon software I could find (CameraControlPro2) allows you to take control of the camera from a PC but not to exploit it any further than the installed firmware.

 I'm assuming you're using a cable release. Does your camera have a mirror lock? It's a good way to reduce vibration when taking individual frames

Yes, I have a cable which links to my iPhone via the mic input and the triggertrap app for auto-controlling many exposure setting (timing, delays, number etc etc) - so far the only useful thing I have discovered about the Nikon for AP - although Canon users have the same thing available to them.  And yes, I do use Mirror-Up mode to reduce vibrations from the mirror movement, but I was presuming that the shutter would still produce unwanted vibrations (esp considering I have a rather flimsy Skywatcher 130p AutoTrak holding a rather weighty D7000).

Just looked at this image again on a decent sized screen and it looks like you have also captured 2 moons. If you check on a program like Stellarium and set it to the time you took the shots it will tell you which ones they are. You might have to flip the image to get the orientation correct. It is only slightly out of focus otherwise the moons would be clearly visible.

Dave, I think you are right and thanks for the tip about Stellarium - what a fab piece of free software - just turned my daunting task of learning all the constellations and sky objects into something far easier and quicker!  Downloaded, changed date and used 'ocular view' to see, what I thought were noise or other stars were in fact probably Ganymede and Callisto!

Anyway, thanks a lot for all of the replies and will keep trying and post improvements as I get better

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Nice effort. You will lose a bit of detail as the Nikon video is compressed, but you can run it through PIPP to get something Registax will process. Using PIPP shouldn't degrade the video quality. At the moment the focus being just off and the over-exposure will hurt the image quality far more than the video compression.

4) Tracking

The set-up manual for the Skywatcher says you can set-up auto-tracking for stars, moon and planets, but there are no settings for changing between these objects and surely they all need to track different planes and rates of movement?  Or am I misunderstanding some of the basics?

You don't need to worry about changing the tracking rates for different objects. They would wander off eventually, but their apparent motion is very small compared to that caused by the Earth's rotation. Accurate tracking isn't terribly important for planetary imaging anyway, Registax will align the frames if there is a bit of drift.

Good luck with the next step, sounds like you are doing a good job of working your way through the problems.

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Nice effort. You will lose a bit of detail as the Nikon video is compressed, but you can run it through PIPP to get something Registax will process.

Does anyone know how much quality is lost from a single image frame of the D7000's full HD high quality mode vs uncompressed AVI.  With a resolution of 1920 x 1080 and using the H.264 codec, I was presuming not very much - but cannot find anything on Google that explains it...

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