Neximage 5 - Beginner First Light Fail. Unable to get any kind of on-screen view.

[WicklowSkies76]

Thanks for reading.

First light last night with a C11 XLT and a Neximage 5, tested on Saturn last night in excellent seeing, but admittedly Saturn was low to the horizon. I have an AZEQ6 GT mount used in Alt Az mode. Despite being able to get Saturn centered using my finderscope and then an 8mm eyepiece into a diagonal, anytime I plug in the Neximage 5 and load up iCap or Sharpcap, no matter what exposure or gain settings I chose I could not see anything on screen in the Software on the laptop other than a black screen. The higher I went with Gain & Exposure I just got a noisy dark pic. I tried slewing every direction, I still couldn't see anything appearing. I am not using a diagonal with the Neximage 5. I just plug it straight into the OTA with the adapter - so I was basically swapping the diagonal with the eyepiece and the Neximage 5 but no joy. Attaching a couple of pics of what I was seeing.

Any tips? Any thoughts on where I might be going wrong?

[WicklowSkies76]

Here's an output of one of the many camera settings I tried...

[NexImage 5]
Binning factor=1
Output Format=AVI files (*.avi)
Colour Space=RGB32
Resolution=640x480
Pan=0
Tilt=0
Frame Rate Limit=30 fps
Gain=21
Exposure=0.0006
Timestamp Frames=Off
Color Enhancement=On
Highlight reduction=Off
Denoise=0
Brightness=-5
Contrast=0
Hue=0
Saturation=64
Sharpness=0
Gamma=100
White Bal (B)=64
White Bal (G)=65
White Bal (R)=98
Temperature=6000
Temperature Preset=Daylight
Auto-Preset=Any
WhiteBalance Mode=Grey World
Auto=On
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.5
#White Point
Display White Point=1
TimeStamp=2019-07-03T22:59:23.8781890Z
SharpCapVersion=3.2.6054.0
 

[Cosmic Geoff]

There is a knack to getting an image on screen, as I discovered when I started planetary imaging.  It's best to practice on the Moon, which is bright and hard to miss. 😦

Gotcha 1 is that unless an object like Saturn is almost in focus, it will not show up on screen no matter what you do.  The camera focus position will be significantly different from the eyepiece focus (typically several mm further in) and you have to find out what that difference is with your setup.   The trick I used is to focus the eyepiece with the eyepiece pulled up by the appropriate distance, and then replace it with the camera, whereupon I can at least find something blurry.

I always image with the diagonal - it's less of a bother and you just tick a box in processing to correct the image.

Gotcha 2 is that the sensor chip is small and the planet image can wander off it.  Here is where you need a well-behaved tracking mount, and at minimum a 9x50 optical finder, accurately aligned.  If you dislike neck-ache you may want to have a RACI finder, and if you have dark skies rather than urban glow, illuminated crosshairs.   You will probably want to image with 320x240 or 480x480 but it is almost impossible to get a subject on this without going to the full chip size to find the subject. and centre it. 

Edited July 4, 2019 by Cosmic Geoff

[WicklowSkies76]

20 minutes ago, Cosmic Geoff said:

There is a knack to getting an image on screen, as I discovered when I started planetary imaging.  It's best to practice on the Moon, which is bright and hard to miss. 😦

Thanks for the tip. Does sound like a focus issue. I thought you would see at least something while out of focus but it could have been majorly out of focus. I will try to hone this focussing skill and difference during the daytime and maybe have another go tonight. Weather permitting.

[JamesF]

Focusing on something as far away as you can manage with the camera might help you find the rough position for the focuser.  The Moon is a good target, as suggested, because it's hard to miss.  Failing that a distant hill or something like that might work in the daytime.  I found a reticle eyepiece very helpful for centering the image.  Even though the target might appear centered in a normal eyepiece, it doesn't have to be far off to miss a camera sensor altogether.

I also found that sometimes you can turn the gain or contrast up high and you might see a slight difference in brightness across the sensor which can help you see where the target is if it doesn't end up on the sensor.

When I'm doing lots of planetary imaging I leave the focuser where it needs to be for the camera to be in focus and do the alignment using a (reticle) eyepiece on the unfocused image.  For alignment it doesn't matter that it's out of focus.

James

[WicklowSkies76]

2 minutes ago, JamesF said:

Focusing on something as far away as you can manage with the camera might help you find the rough position for the focuser.  The Moon is a good target, as suggested, because it's hard to miss.  Failing that a distant hill or something like that might work in the daytime.  I found a reticle eyepiece very helpful for centering the image.  Even though the target might appear centered in a normal eyepiece, it doesn't have to be far off to miss a camera sensor altogether.

I also found that sometimes you can turn the gain or contrast up high and you might see a slight difference in brightness across the sensor which can help you see where the target is if it doesn't end up on the sensor.

When I'm doing lots of planetary imaging I leave the focuser where it needs to be for the camera to be in focus and do the alignment using a (reticle) eyepiece on the unfocused image.  For alignment it doesn't matter that it's out of focus.

James

Thanks James - great tips. Will for sure be trying those out. Especially the focus tip.

[noah4x4]

I have the similar NexImage Burst and if using an Alt-Az scope I  found it very difficult to hold a planetary image in its FOV without accurate  polar alignment (on wedge), and detailed attention to tracking and backlash accuracy. The magnification is so great and the FOV so small it requires pin-point precision. To be frank, it was more luck than judgement.. But below is an image of Jupiter. To be honest, after capturing this, I gave up and moved onto a  DSO camera as the planetary camera was frustrating to use.

Edited July 5, 2019 by noah4x4

[Peter Drew]

I made an eyepiece adaptor which held it at exactly the correct focal point as that of the camera.    😀

[WicklowSkies76]

Thanks everyone - I wasn't able to test this on a planet due to clouds but I did experiment with focus during the day and realised that until focus is correct the planet could be on the chip but I might not be able to see it. I also realised that counter intuitively, the focus needed for my 40mm plossl eyepiece and the Neximage 5 are quite close. So if I can get the planet centered (as much as is possible using a 40mm eyepiece) and in focus using this eyepiece, the focus on the Neximage will be close. Then it's a matter of swapping in the Neximage for the eyepiece, cranking up the resolution and the gain/exposure till I locate the target, then hand control while I capture.

 

It's a lot more challenging than I thought it would be. It's just a huge magnification and such a small FOV. I am sure it will be worth it. Typically now that I have some spare time for the next 2 days, the clouds have rolled in. Ugh the frustration wink.gif ! 

 

Not using a Barlow as I'm attempting to image at f/10 and a 2800mm f/l - so barlow not needed with Neximage 5 and this size of SCT.

[Science562h]

Sort it out? I have the Neximage 5 & it's a basic widefield camera, not narrowfield.

Option 1
I found your problem, you are starting, at too low "Resolution." You can leave auto on, for gain. Go ahead & max out your resolution, at 2592x1944. You just have to get Saturn displayed on screen somewhere first. Center it, with hand controller, move it 'till centered & focus it. Now, lower resolution to 1920x1080; center it. Now, lower it, to 640x480 and center it. The planet should be centered, if you are tracking. Record.

 
Option2
Start, at 2592x1944, use binning & decrease view to 20%. Saturn should be there, with the Neximage 5. Center Saturn, with your 'scopes tracker. Repeat, at lower resolutions, 'till you reach 640x480. Record.

The Neximage 5 has a basic FPS Max of 52 FPS, at 640x480, not 30 FPS. Max it out. This is the N5's resolution chart:
640x480  50-52     
1024x768    27       
1280x720    25    
1280x960    19
1920x1080  13
1600x1200  13    
2048x1536   9
2560x1920  6    
2592x1944  6

You can increase the Neximage 5's FPS, by choosing "Region of Interest (ROI)." With ROI selected, Jupiter records, like this:
N5: 328x264
1 min @ 115 FPS.............6,900 Frames
1:30 min @ 115 FPS.......10,350 Frames
2 min @ 115 FPS.............13,800 Frames 

   
With ROI selected, Saturn records, 136x108, at 316 FPS. This is the quick chart:
1 min @ 316 FPS..........18,960 Frames
1:30 min @ 316 FPS.....28,350 Frames
2 min @ 316 FPS...........37,800 Frames

That's a-lot of frames for a USB 2.0 camera. N5 users are not limited to 640x480, at 50-52 FPS. You can get 100-315 FPS or so, if you ROI planets. If you still need more, get the Neximage 10 (N10), which is twice as good & faster. Basically, double the N5's FPS, per above chart. That's 37,000 frames for Saturn, not 750, 1,000 or a few thousand! You must master your Neximage 5 & iCap to its potential.

Edited January 20, 2020 by Science562h
Grammar

[WicklowSkies76]

22 minutes ago, Science562h said:

Sort it out? I have the Neximage 5 & it's a basic widefield camera, not narrowfield.

Option 1
I found your problem, you are starting, at too low "Resolution." You can leave auto on, for gain. Go ahead & max out your resolution, at 2592x1944. You just have to get Saturn displayed on screen somewhere first. Center it, with hand controller, move it 'till centered & focus it. Now, lower resolution to 1920x1080; center it. Now, lower it, to 640x480 and center it. The planet should be centered, if you are tracking. Record.

 
Option2
Start, at 2592x1944, use binning & decrease view to 20%. Saturn should be there, with the Neximage 5. Center Saturn, with your 'scopes tracker. Repeat, at lower resolutions, 'till you reach 640x480. Record.

The Neximage 5 has a basic FPS Max of 52 FPS, at 640x480, not 30 FPS. Max it out. This is the N5's resolution chart:
640x480  50-52     
1024x768    27       
1280x720    25    
1280x960    19
1920x1080  13
1600x1200  13    
2048x1536   9
2560x1920  6    
2592x1944  6

You can increase the Neximage 5's FPS, by choosing "Region of Interest (ROI)." With ROI selected, Jupiter records, like this:
N5: 328x264
1 min @ 115 FPS.............6,900 Frames
1:30 min @ 115 FPS.......10,350 Frames
2 min @ 115 FPS.............13,800 Frames 

   
With ROI selected, Saturn records, 136x108, at 316 FPS. This is the quick chart:
1 min @ 316 FPS..........18,960 Frames
1:30 min @ 316 FPS.....28,350 Frames
2 min @ 316 FPS...........37,800 Frames

That's a-lot of frames for a USB 2.0 camera. N5 users are not limited to 640x480, at 50-52 FPS. You can get 100-315 FPS or so, if you ROI planets. If you still need more, get the Neximage 10 (N10), which is twice as good & faster. Basically, double the N5's FPS, per above chart. That's 37,000 frames for Saturn, not 750, 1,000 or a few thousand! You must master your Neximage 5 & iCap to its potential.

Thank you!! That's great info. I managed to fumble my way through thanks to all the advice I received on here. It was basically down to focus initally and settings. Then also I realized that you need to have the planet in the top left quadrant of the view in order to make sure you don't lose it when you step down the resolution, that way is stays in the FOV. I will look at your details more closely when I get going on planetary again... my seeing here at 53 degrees north is pants so there's a limit to what results I can get here I fear.

[2STAR]

Give the eyepiece a miss ,Use a Telrad to get you on target, then mess with your settings, Alt/Az works fine.

eric