#1  
Old 29-03-2014, 10:49 PM
southozsmithy (Chris)
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Nikon D3000 Astrophotography

Hi there, Long time reader, 1st time poster.
I have a Nikon D3000 camera and recently purchased a TAL1 telescope with motor drive (which I haven't plugged in yet). It has the piggy back attachment and I have purchased a t-ring and adapter.
After trying to familiarize myself with the telescope I thought I would try and take some pictures.
I lined up Jupiter and got a beautiful view through the eye piece, took it out and put the camera in and snapped away. Nothing ! All I get in the display of my D3000 is black. This is the case whether I choose an ISO between 200 or 1600, or hold the button down for 1 second or 60. I have tried using a barlow lens rather than the adapter and still the same result. Any setting I try I have no result.
So I went for something easier like the moon. It was just an out of focus picture that looked like I photographed a nearby plume of smoke.
I understand the focus on the D3000 isn't great when the lens is removed and only bulb in manual mode is available other than some exposure settings in aperture mode.
I wasn't under any illusion that this would be easy but I am at my wits end now wanting to get some results on the large outlay I just made.
Any help is VERY much appreciated.
Thanks
Chris
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  #2  
Old 30-03-2014, 12:21 AM
raymo
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I don't have a lot of info to work with, but your problem shouldn't be too
hard to pin down. Firstly, Saturn at prime focus [ camera coupled to scope directly with no eyepiece] would be very very small in a short focal length scope like yours, and therefore hard to find in the camera's viewfinder.I don't think the D3000 has live view to help you.
Regarding the moon; this might uncover the problem. If you can only
get an image that is way out of focus, it is possible that your scope will
not come to prime focus with your camera as it is presently mounted.
Many Newtonians have this problem. Some can be made to work by
using shorter couplings between the camera and the focuser, and others have to have the primary mirror moved up the tube a bit.
In daylight mount the camera and try to focus on something at least
500metres away. If it won't focus, remove the T-ring and any other
adaptor, and move closer to the open end of the focuser while looking through the viewfinder. If it then comes to focus, or is obviously
getting nearer to it, you have found the problem. Then you can look at ways of fixing it.
raymo
P.S. when looking through the viewfinder at the open end of the focuser make sure the focuser is racked all the way in.
Regarding the focus on the D3000 being not great when no lens is fitted. You cannot focus with the camera without a lens; you have to use the scope's focuser to focus the image.

Last edited by raymo; 30-03-2014 at 12:22 PM. Reason: more info
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  #3  
Old 30-03-2014, 03:45 PM
southozsmithy (Chris)
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Thanks for the reply.
I'll have a go this afternoon and see what results I get
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  #4  
Old 18-04-2014, 04:55 PM
southozsmithy (Chris)
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With a bit more research I managed to take my 1st decent moon shot. It was a very bright full moon using my t-adapter and 2Xbarlow.
Couldn't get the entire moon into the shot, any easy fix to "focusing out" so to speak to get a smaller shot of the entire moon?
Attached Thumbnails
Click for full-size image (DSC_3621.JPG)
78.0 KB147 views
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Old 18-04-2014, 07:52 PM
raymo
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Hi Again Chris, I'm still not exactly sure how you've got your camera
connected to the scope. If you are using the complete barlow as part
of the connecting mechanism, unscrewing and removing the barlow's
lens will make the moon much smaller, and nicely framed. If you are
using the barlow separately, just don't use it, and the moon's apparent
size will be halved. In astrophotography focus is critical; assuming that
your optics are o.k. your focus is a bit off. Needs a lot of care. As I don't
know what shutter speed you used, I can surmise that if it was too slow,
the moon's movement might have contributed to the apparent soft
focus. If you still have problems, post a pic of your camera to scope
set up. It might help IIS members put you on the right track.
raymo
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Old 18-04-2014, 08:52 PM
southozsmithy (Chris)
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Hi raymo and thanks for the reply, it's much appreciated.
I am using the complete barlow X2.
When I unscrew the lens, i can't focus nicely at all.
This is probably because the rim of the barlow without the lens seems a little larger and can only sit on the periphery of the telescopes eye piece holder rather than enter it.
I have attached 2 pics I took of the moon tonight.
One is quite obviously without the lens and one with.
I had my setting to ISO 100 and shutter speed 1/2000.
When I took the better pic it did seem quite well focused in the viewfinder.
I do appreciate your help so far.
Attached Thumbnails
Click for full-size image (image without barlow lens.JPG)
162.7 KB51 views
Click for full-size image (image with barlow lens.jpg)
48.2 KB115 views
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Old 18-04-2014, 09:41 PM
pw (Peter)
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I suspect you can't get the focuser in far enough on that scope. For the TAL2 and others you can remove the eyepiece adapter and put the camera on the remaining part of the focuser.
For astrophotography with TAL-2,
TAL-150P and TAL-150P8 telescopes
use the same procedure as
described above. However prime
focus photography is also available
when using M42x1 objective thread
cameras (M42x0.75 thread camera
adapter is also supplied with the
telescope).
For the prime focus setup unscrew
the objective lens from the camera
and remove the 2" and 1.25" adapters
from the focuser drawtube.
Screw the camera adapter into
the focuser drawtube. Attach the
T-ring (T-adapter) to the camera and
thread it onto the camera adapter.
Mount the camera (2).

I found the instructions at
http://www.npzoptics.com/files/TAL1,1M,2,150P,150P8.pdf
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Old 18-04-2014, 10:01 PM
raymo
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O.K. firstly, I just noticed that your barlowed image is only 48.2 kb;
that will lower the quality of the image. Your focus may not be so bad after all. You need to post larger images, near to the 200kb limit.
PW appears to have found the answer to your problem, but one tip
could be useful. DSLRs suffer badly from mirror and shutter vibration,
so a really high shutter speed helps greatly, as the exposure is over before the vibrations can get started. Experiment with ISO 200 and
1/3200th or 1/4000th of a sec. These figures will need to be changed
according to the phase of the moon.
raymo
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Old 18-04-2014, 10:39 PM
southozsmithy (Chris)
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Thankyou PW and raymo.
The image supplied was compressed for uploading purposes.
I thought it would be good manners to do that rather than upload a 2meg picture.
I will see if i can remove the eyepiece adapter and fit the barlow without lens into it tomorrow night and report back with a picture of the moon uncompressed.
I knew this wasn't going to be easy......just more frustrating than I thought.

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Old 18-04-2014, 11:02 PM
raymo
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I understand that the image was compressed, but it was compressed 4
times more than necessary. In this instance it's nice to have good manners, but unnecessary, as you can't upload anything larger than
200kb anyway. You'll still have to compress the image, but only down to just under 200kb.
raymo
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  #11  
Old 18-04-2014, 11:29 PM
southozsmithy (Chris)
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Just had a look and there is no way I can fit the Barlow into the eye piece without the lens attached.
Not the biggest of my problems I guess but still frustrating.
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  #12  
Old 19-04-2014, 05:42 AM
pw (Peter)
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Use a t-mount to Nikon F adapter to fit the camera to the focuser without the barlow if possible.
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