Return to the Cloudy Nights Telescope Reviews home page


Telescope Specific Forums >> Celestron NexStar

Pages: 1 | 2 | 3 | 4 | 5 | (show all)
Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5225099 - 05/16/12 01:06 PM Attachment (24 downloads)

Hi Harioharima,

And, if I haven't said before; a very hearty welcome to CN and to this forum !

When you "Set Up Camera" (i.e. your Neximage) in "Craterlet", you are instantly given a " Remove Flicker" window which relates to your mains electrical system. In Europe we work on 50Hz. but I believe the US works with 60Hz (the default).

If you are therefore in Europe, then this may be the cause of your screen image flicker and if so apply the option.

As to the image appearing green-ish on screen, this is quite normal, at least as far as my experience takes me, and I use "Craterlet". Here attached is a screen shot from the last AVI raw, unprocessed image of Saturn I captured. This is easily corrected to the appropriate colour(s) at the processing stage.

Hoping this helps,
Best regards,
Tel


Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: Tel]
      #5230010 - 05/19/12 05:18 PM Attachment (19 downloads)

Quote:

Hi Harioharima,

And, if I haven't said before; a very hearty welcome to CN and to this forum !

When you "Set Up Camera" (i.e. your Neximage) in "Craterlet", you are instantly given a " Remove Flicker" window which relates to your mains electrical system. In Europe we work on 50Hz. but I believe the US works with 60Hz (the default).

If you are therefore in Europe, then this may be the cause of your screen image flicker and if so apply the option.

As to the image appearing green-ish on screen, this is quite normal, at least as far as my experience takes me, and I use "Craterlet". Here attached is a screen shot from the last AVI raw, unprocessed image of Saturn I captured. This is easily corrected to the appropriate colour(s) at the processing stage.

Hoping this helps,
Best regards,
Tel




Hi Tel, Thank you for the detailed response. The pic you put up is orders of magnitude superior to anything i've managed to see with my neximage.

I tried most of the suggestions again without any success. I only get a lump no matter how slowly and patiently I try focus. Last night, the views of Saturn through my eyepiece were breathtaking but despite spending a lot of time, i got nothing better than the attachment. I am beginning to think that the neximage I purchased is defective.

Is there any test possible to figure out whether the sensor is ok? I tried using it indoors to image various objects but it shows nothing (at any focal distance) but perhaps it isn't designed for use as an ordinary camera.

Thanks for any suggestions.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5230088 - 05/19/12 06:47 PM

Hi Harioharima,

I've just picked up you posting but must away to my bed: time here in the UK approaching midnight !


However, before we discuss anything further, can you please provide details of the 'scope you are using in this respect and whether you are attempting your imaging with your Neximage camera via the use of Barlow lenses, or not as the case may be ?

If you can provide such information and anything else you think relevant, I promise I will look at the problem as soon as awake tomorrow morning !

Best regards and goodnight,
Tel


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5230112 - 05/19/12 07:19 PM

It looks like you're over exposed. Can you turn down the brightness and gain? Also try a faster frame rate. These things will make the image darker. Also, you can use a Barlow lens which will make it darker (and larger).

Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: WarmWeatherGuy]
      #5230150 - 05/19/12 07:45 PM

Tel and WarmWeatherGuy, Thanks for posting. Here are some details:
1. I am NOT using a Barlow (don't have one).
2. Scope is a Nexstar N5. My alignment and tracking were bang-on last night with no drift. Image with eyepiece (a recently acquired 8-24mm Celestron Zoom) was absolutely incredible (I could see the CD quite well). So I was disappointed not to have the neximage capturing properly.
3. I experimented with framerates of 10fps and 5fps.
4. I did enable the 60Hz antiflicker (I am in US) but I was only using battery power on the tablet, not ac.
5. The image size with neximage seemed to be selected by craterlet (it was a smallish 117x200 or something like that. When using my tablet's front camera, crater shows an image (of my face) at 640x480
6. I didn't change any of the image settings....perhaps i will experiment with brightness and gain as WWG suggests.
7. What framerate should i try? (I read somewhere that 5 to 10fps is recommended)
8. Do you guys see Saturn LIVE on the computer screen like Tel's image? I've tried both snapshot mode and avi-- both images looked like what i posted previously.


Hope some of what I typed is useful info to diagnose the issue. All I've done is view/center Saturn with my zoom eyepiece magnified to 8mm (or 10mm). Then I replace the eyepiece with the neximage (connected via usb). I try my best to focus s-l-0-w-ly and am sure I didn't shoot past the perfect focus image.

Thanks again.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5230169 - 05/19/12 08:03 PM Attachment (18 downloads)

I am not familiar with craterlet but it should allow you to specify the image size. I use HandiAvi which you can use for free for 10 days.
http://www.azcendant.com/
There are two windows that you should be able to bring up that are provided by the NexImage drivers. One window lets you choose the image size and the other lets you select the brightness, shutter speed, gain, and frame rate. See attached picture.

You should see a live image of Saturn. If you have a frame rate of 5 per second then it will only update 5 times a second. If you don't see a live image then I would work to fix that first.

With a live image you can simply turn down the brightness, gain, and increase the shutter speed to make the image be less bright. You might be able to use a frame rate of 20 or even 25.


Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: WarmWeatherGuy]
      #5230211 - 05/19/12 08:40 PM

Thanks WarmWeatherGuy. I will try the software you linked and tweak gain etc. So far I've just let the software pick values automatically.

I do see a live image but it looks like what I posted previously, not like what Tel did.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5230369 - 05/19/12 11:37 PM Attachment (21 downloads)

Attached is a picture of Saturn I just took using my NexStar 5SE and the NexImage. It is an animation toggling between the stacked image and the wavelet image. This is at 25 frames per second and taking 600 frames.

I do not know what a NexStar N5 is but it looks similar to mine based on the relative size of Saturn in our pictures.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: WarmWeatherGuy]
      #5230371 - 05/19/12 11:41 PM Attachment (20 downloads)

Here is another picture I just took using the NexStar 5SE and NexImage but also using a 2.5x Powermate, which is basically a really nice Barlow. This converts my telescope from a 1250mm f/10 to a 3125mm f/25. Consequently I had to drop down to 10 frames per second. I took 600 frames as before.

Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: WarmWeatherGuy]
      #5230386 - 05/19/12 11:58 PM Attachment (22 downloads)

I just got back and did manage some improvement entirely thanks to your suggestions -- i turned down the gain, and turned OFF the anti-flicker feature.

Warmweather guy, what I've got is nothing near what you've posted but I think I managed to verify the camera isn't the weak-link - it is me! Thank you.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5230400 - 05/20/12 12:17 AM

What you have looks almost identical to my 1x stacked (no wavelet) image above. You can squeeze out a little more by doing the wavelet thing in RegiStax. A much bigger improvement can be had by using a Barlow lens. Also notice that RegiStax can improve the 2.5x image more than it can improve the 1x image (in the animations above).

I see two differences in your picture and mine. I have North up. To do this I point the NexImage camera North. On the camera the end where the wire comes out is the end that points up.

The other difference is just the brightness. Other than that I would say your picture is the same as mine.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: WarmWeatherGuy]
      #5230523 - 05/20/12 03:18 AM

Hi Harioharima,

I think that between you and WarWeatherGuy, you've virtually solved your problem ! All I can perhaps add is that it looks as if you haven't being applying the image size variation Craterlet offers. To effect this, press "Mode" on the Craterlet screen to apply the maximum image size of 640 X 480.

Additionally, I'd certainly recommend that you boost your focal ratio to something like f/20, (X2 Barlow or Powermate), or even f/30, (X3 Barlow), although the latter might be a little too much for a 5" aperture 'scope, plus the fact that the higher you push the magnification the less positive the spur gear driven tracking is likely to be due to the diminished field of view.

As to the image set up, as WWG advised, keep the Gain on the dimmer side and, in my opinion, the Gamma at zero. Vary the brightness and contrast to suit but as said, ebb on the dim side for your image capture and use a shutter speed of between 5 and 20 frames per second in order to avoid too much image compression.

Hoping these few additional comments help.

Best regards,
Tel


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: Tel]
      #5230558 - 05/20/12 06:18 AM Attachment (22 downloads)

Hi HH,

Just to give you an idea of your 'scope's potential for planetary imaging, I ran your above image through some of the relevant Photoshop features and modified its size a little.

Obviously there's not too much in the way of detail in this one, but once you get into the practice of accurate focusing and full use of "Craterlet", I'm sure you will soon be attaining great results.

Best regards,
Tel


Post Extras: Print Post   Remind Me!   Notify Moderator  
herrointment
Post Laureate
*****

Reged: 03/12/11

Loc: North of Hwy. 64
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: Tel]
      #5230576 - 05/20/12 07:14 AM

These cameras pretty much require the use of a barlow to produce an image that is large enough to show detail.

I adjust my settings at the laptop so that the live image is a bit dim to my eyes and take as many 2 minute exposures as I can - adjusting settings as I go.

This shoot until I hit it method works especially if the capture program will save a list of your settings with each capture. I've had some luck with SharpCap.

Try and then try again. You'll get a real good one eventually and then it's all up to the seeing conditions (which play a huge role), free time during said conditions and of course luck. I can't tell you how many times I've gotten set up and after numerous snafus was finally ready to take some exposures that the target vanished behind a tree branch.


Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: herrointment]
      #5232429 - 05/21/12 12:37 PM

Thank you Tel, WWT, Herrointment. I will procure a Barlow and try for more improvement. Also Registax at this point is bufuddling for me, it will probably be a month before I will be ready to use that.

Also, I now have a 8-24 zoom eyepiece that has T-threading (if I am correct). I am curious to try directly photographing (with a interchangeable lens camera) into the eyepiece. Wonder if that would produce better images -- particularly because seeing with the eye seems way superior to a single frame capture with the neximage. I won't be able to try that for a week or two but will post if/when I do.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WarmWeatherGuy
Carpal Tunnel
*****

Reged: 08/27/11

Loc: Orlando, FL 28 N, 81 W
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5232467 - 05/21/12 01:03 PM

What you're talking about is called afocal photography.

http://en.wikipedia.org/wiki/Afocal_photography

From my experience I get better pictures with fewer optical elements. The eyepiece projection often gives too much power and not enough light.

The Barlow and Registax will give you the greatest improvement. You can get a used Barlow on eBay for well under $40.

To learn how to use Registax you can go to YouTube and search for Registax and watch some of the videos there. Here is one by AstronomyShed:

Registax 6.Primer
http://www.youtube.com/watch?v=ALqQfExMRBA


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5232516 - 05/21/12 01:36 PM

Hi HH,

Personally, I would not recommend a-focal imaging before you have good experience of prime focal astrophotography. To be honest, I can't say that I've ever seen it done with a Neximage or webcam but then perhaps, I haven't lived (?)

I would suggest, (perhaps as before), that you get yourself a Bahtinov mask, (if you don't have one already). Then, with your new Barlow attached to your Neximage, first focus accurately on one of the brighter stars in our skies at the moment.

Once the Bahtinov mask indicates "best focus", slew to your target planet and look for its appearance on your Craterlet screen. The chances are though it won't be there for various reasons; normally attributable to the lesser accuracy of the slew and to the very small FOV presented to the Barlowed Neximage.

As I think I've already mentioned somewhere earlier, no matter: just remove the camera assembly and substitute it with a 25mm EP WITHOUT touching the focuser. You should then see the planetary image you seek, albeit probably blurred, but visible enough to allow its centralisation in the EP. Once centralised, remove the EP and replace it with the Barlowed Neximage which should have remained in focus.(If not make some minor "tweaks" to it but bear in mind that by and large, you will see the image on screen as somewhat of a blur as it "boils" in the Earth's atmosphere) !

Now, with "something" on screen, make your adjustments to Craterlet, (i.e. reducing the Gain so as not to give too bright an image and setting your shutter speed to something less than say, 25 frames/second. Keep the Gamma setting at Zero and make minor adjustments, if you think necessary, to the brightness and contrast. I can't overemphasise though the need to keep the image more on the dim rather than the bright side. Brightness and contrast etc. will come to the image during post capture processing.

Try to capture at least ca. 2000 frames when you're good to go. When you have them, I or for sure others, will certainly help you align and stack them in Registax and indeed take you through the entire process.

Hoping this helps you a little further,

Best regards,
Tel


Post Extras: Print Post   Remind Me!   Notify Moderator  
harioharima
member


Reged: 10/05/11

Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: Tel]
      #5232616 - 05/21/12 02:36 PM

Tel and WWT,

I read the wikipedia article that WWT linked- I am not sure that what I described is afocal photography. In afocal, the camera WITH a lens seems somehow attached to the OTA. I've also seen some pics where a camera (no lens) is attached to the OTA (with no telescope eyepiece).

What I posted seems a bit different (?)-- I want to attach an interchangeable lens camera WITHOUT lens (i.e. sensor only) to the telescope-eye-piece. This 8-24 eyepiece seems have a T-threading on the outside (haven't seen this on other eyepieces).

The great views seen by the naked eye seem bright enough for a MFT camera to capture but I could be wrong.

I do intend persevering along the lines you suggest with the neximage also...the clicking camera would be a side diversion. It will be a bit before i go for the mask approach, but if i manage to record a nice long avi, this is where i will come.

PS: Also thanks for the youtube link, that would probably be the way to learn for someone like me. :-)


Post Extras: Print Post   Remind Me!   Notify Moderator  
Arctic_Eddie
Post Laureate
*****

Reged: 12/30/07

Loc: St. Petersburg, FL
Re: Where Oh Where Has the Cel. NexImage Camera Gone? new [Re: harioharima]
      #5232686 - 05/21/12 03:32 PM

I've used that setup with marginal results. By marginal I mean only narrow FOV and difficulty focusing due to scope vibration. I have the setup in place on an AT80EDTA and ready for the Venus transit. Also present is an improvised mounting plate and my newly built stepper focuser. A photograph is forthcoming. You will need an adapter to go on the EP to accept the camera. Agena has one just for that purpose. The adapter screws directly onto the back of a Celestron 8-24mm zoom eyepiece T threads then accepts any webcam with a 1.25" snout.

http://agenaastro.com/blue-fireball-1-25-t-t2-visual-back-e-10.html


Post Extras: Print Post   Remind Me!   Notify Moderator  
Arctic_Eddie
Post Laureate
*****

Reged: 12/30/07

Loc: St. Petersburg, FL
Re: Where Oh Where Has the Cel. NexImage Camera Gone? [Re: Arctic_Eddie]
      #5232707 - 05/21/12 03:44 PM Attachment (14 downloads)

Here's the photo of a Philips SPC900 webcam mounted on a Celestron 8-24mm zoom eyepiece. It uses the Agena/Blue Fireball adapter. Also present is the stepper focuser. A solar filter will be attached for the Venus transit event.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | 4 | 5 | (show all)


Extra information
3 registered and 24 anonymous users are browsing this forum.

Moderator:  Brian Risley, panhard, Mitchell Duke, mayidunk 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 5686

Jump to

CN Forums Home




Cloudy Nights Sponsor: Astronomics