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Flea 3 pixels and exposure

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#1 bunyon

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Posted 13 December 2012 - 04:58 PM

Playing with the Flea3 today, I was looking into longer exposures (as per the other thread). However, I can't seem to make it take longer than 1.05s exposure - despite the Point Grey site indicating it can go as high as 30s.

Does anyone know how to get longer exposures out of it?

Also, on a 1s exposure, there are a number of lit up pixels. Should these worry me? (there are 4)

#2 Rankinstudio

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Posted 13 December 2012 - 07:22 PM

Good luck on that lol. I went down this road and ended up messing with the software for hours with no luck getting to 30 seconds.

The 4 pixels are nothing to worry about. They are hot pixels, every sensor has them :)

#3 DesertRat

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Posted 13 December 2012 - 07:35 PM

You can have dead pixels, warm pixels and hot pixels. I've got 8 hot pixels defined in my FireCapture.ini file. So at 4 count yourself lucky!

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#4 skywatch

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Posted 14 December 2012 - 10:13 AM

Hot pixels can be eliminated. They can mess up the alignment and quality algorithm. There is a map in the Flea3 which does this. Over time, more hot pixels will develop. I asked Point Grey how to modify the map but they wouldn't tell me - just how to turn it on and off. I sent it back under warranty and they re-mapped the hot pixels out very effectively. I don't know what I will do when the warranty expires and more develop.

-Rolf

#5 Rankinstudio

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Posted 14 December 2012 - 10:32 AM

I have two or three and have never had any alignment issues. As long as you don't select one as an align point it will cancel itself out if there is any slight movement of Jupiter on the imaging sensor.

#6 bunyon

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Posted 14 December 2012 - 10:45 AM

Thanks guys. I'm not concerned about the pixels too much and am reassured by the posts above. I will look into mapping it just in case it becomes a problem. I simply had never noticed. Imaging with my Dob, it's a bit of a fight to keep the planet on chip - think Apollo 13 when Lovell was trying to keep Earth in the window. So, no pixel remains long in one spot on the disk.

As for the exposure, I found some information online. Egad. Sounds tricky. I have what I think is a clever idea but needs longer exposure - first time I've wished I hadn't sold my DMK, it would be perfect. Of course, what is probably happening is that Point Grey is saving me from my "cleverness".

#7 Rankinstudio

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Posted 14 December 2012 - 10:57 AM

Paul, I had the same regret assuming I could do shots with the Flea3 like I had done with my DMK21.

I really liked the image scale it had on the more distant galaxies:

http://www.slas.us/g...?g2_itemId=4159

http://www.slas.us/g...?g2_itemId=4161

http://www.slas.us/g...?g2_itemId=4163

I think I am going to pick up one of these ASI120MM cameras for smaller galaxies - see how it does.

#8 skywatch

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Posted 14 December 2012 - 11:53 AM

I have two or three and have never had any alignment issues. As long as you don't select one as an align point it will cancel itself out if there is any slight movement of Jupiter on the imaging sensor.


True, if the hot pixel is guaranteed not to be in an alignment box then it is OK. However, with Jupiter being very large, this may be hard to avoid if there are many hot pixels.

In one extreme, when I have used a DSLR for imaging Jupiter, I had to be very careful to avoid alignment points which included dust motes because they showed up very clearly after alignment. A single hot pixel won't have as great a visible impact, but the effect is still there to some extent if it is in an alignment box.

It is a case of the problem being worst if the seeing is excellent and the mount tracks very well. Then the hot pixel won't move around enough. Do we really want to depend on poor conditions to dither the hot pixels?

-Rolf

#9 DonAtPointGrey

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Posted 17 December 2012 - 01:16 PM

Playing with the Flea3 today, I was looking into longer exposures (as per the other thread). However, I can't seem to make it take longer than 1.05s exposure - despite the Point Grey site indicating it can go as high as 30s.

Does anyone know how to get longer exposures out of it?


Hi Paul,

Regarding exposure times... I thought I would try this out myself. I was using a Flea3 GigE with a 2.8mp sensor (which is a new one so it is not the same as what you are using).

First I went to the KB article
http://www.ptgrey.co...=166&ST=shutter
It is always a good idea to check the Knowledge Base but it isn't always up-to-date. In this case it told me to turn the FRAME_RATE register off, which I did, and I got a maximum shutter time of 2000ms - so only 2 seconds. Then, relying on my insider knowledge I decided to try Format 7 Mode 7 mode - which I know is the "low noise but slower frame rate" mode. Sure enough, when I set it into this mode, turned the frame rate on and off again (to reset the FlyCap GUI slider bar) I then had a maximum shutter time of 32000ms (32s).

So I expect the Format 7 Mode 7 change is what you guys are missing.

Doing this with the FlyCap GUI you would
1) start up the camera
2) open the settings dialog
3) select the "custom video modes" button in the left-hand button panel
4) in the custom video mode options, select Mode => 7, push apply
5) select the "camera settings" button in the left hand button panel
6) click Shutter Auto toggle to unchecked, and slide the shutter setting all the way to the right - note the maximum shutter time (Ok, now working around a bug in our GUI, check auto shutter back on again, so the slider position gets updated regularly)
7) click the FrameRate On/Off toggle button to unchecked
- what you should then see is that the current shutter position in the slider suddenly becomes not all the way to the right, it becomes actually close to the left hand end of the slider, giving you lots of room to slide more shutter.
8) re-uncheck the shutter auto toggle and re-slide the shutter all the way to the right and see what maximum shutter time you get. You should see something that makes you happy.

I know it is a lot of steps... fundamentally the camera must be
- in Format 7 Mode 7
- FrameRate must be "off"
- shutter must be "manual" (i.e. not auto) as auto shutter will not make use of the extended shutter modes
- then you need to set the shutter yourself

I hope this helps. Also, when trying to figure this kind of thing out the best thing to do is email support@ptgrey.com... I don't monitor this forum closely enough to catch every thread like this that comes by :)

Don

#10 bunyon

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Posted 17 December 2012 - 03:06 PM

Don, thanks. I confess to not having looked real hard for this info. I tried, couldn't figure it out and asked here. I've been busy but, as you say, there are many more avenues of inquiry I might have pursued.

I look forward to playing with this over the next few less hectic weeks. Perhaps there is still time for me to try to be clever.

By the way, does one need to reset the format and mode to use the camera "normally"?

Thanks again.

#11 DonAtPointGrey

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Posted 17 December 2012 - 03:37 PM

...

By the way, does one need to reset the format and mode to use the camera "normally"?


Hi Paul,

The camera would typically always come up in the same video format, which would not be format 7, it would be a "standard video mode" (there is another settings tab for that).

If you want to get fancy... what you can do is set up the camera in the mode you want (video mode, shutter settings, frame rate settings, etc). Then go to the "Advanced Camera Settings" page, and select Memory Channel 1 or 2 and hit the "Save" button. Now whenever the camera starts up, it will start with the settings you saved. You can go to the Memory Channel selection and select another channel and hit "Restore" and you will switch to that Memory Channel setting. Whichever Memory Channel you are on when you shutdown, that is the Memory Channel you will use when you start up.

This way you could set up Memory Channel 1 for long exposure, and Memory Channel 2 for high speed grabbing, for example, and then it would mean you don't need to go through all the settings by hand, you could just restore Channel 1 or Channel 2 and jump to the right settings.

I hope that helps.

Don

#12 bunyon

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Posted 04 January 2013 - 09:44 PM

Don, no joy. Your sequence leaves me at 2s max. I've emailed support but if you have any other ideas...

Thanks.

#13 Mike Phillips

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Posted 05 January 2013 - 12:52 PM

I have the 1394 model, I'll try and let you know.

Mike

#14 DonAtPointGrey

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Posted 07 January 2013 - 02:01 PM

Don, no joy. Your sequence leaves me at 2s max. I've emailed support but if you have any other ideas...

Thanks.


Hi Paul - I tracked down a camera of the exact model that you have and did the following:
- in default operation mode
- turn framerate "off"
- turn auto shutter "off"
- push up the slider shutter to max - I get 2s
- go to advanced video mode, put camera in Mode 7
- go back to settings and drag the slider again (you have to touch the slider, its not smart enough to requery the camera after the Mode change) and it goes up to 32s

So, we should continue to push this through support. They should be checking things with you such as your firmware version. I'll chime in on your support ticket.

Sorry for the rigamarole. I know it can work, we just need to find the right incantation.

Don

#15 bunyon

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Posted 07 January 2013 - 02:25 PM

Don, one problem I see right off is that when I do the first two things: turn off framerate and auto shutter, I only get 1s max. Changing to Mode 7 gets me 2s.

#16 bunyon

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Posted 07 January 2013 - 04:52 PM

Don, thanks for your help in getting this figured out.

All, it was an outdated driver. Don and the folks at PGR (Nina and Gary in this case), tracked it down and got me the right driver and I can now take a 32s exposure.

#17 bunyon

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Posted 07 January 2013 - 05:16 PM

Note: Don's instructions above are bang on with the correct driver.

#18 DonAtPointGrey

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Posted 07 January 2013 - 06:17 PM



Just to clarify, it was a change in camera firmware, not the PC driver.

Sorry Paul, I'm not in the support dept, so I don't see these things often enough. If I was I probably would have twigged to checking the firmware version earlier.

I'm glad it is working for you now!

Don

#19 bunyon

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Posted 07 January 2013 - 07:42 PM

Right, firmware. D'oh.






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