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Qhy8l last night


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Last night looked a pretty clear night so I got everything set up not to much luck.

My guide camera showing stars that it's pointing at but the qhy8l just showing extremely faint pins of light if at all anything. Even moving the sliders every direction didn't reward with anything.

Is this the effects of the summer solstice not so dark skies or still pointing towards a dodgy ccd camera?

 

Cheers

 

Stu 

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1 hour ago, Stu Wilson said:

My guide camera showing stars that it's pointing at but the qhy8l just showing extremely faint pins of light if at all anything

Are you sure those aren't hot pixels? I'm just trying to figure out if there's something going on with the camera hardware/firmware. If I were you, I'd try shooting daytime images. Maybe with a pinhole as lens.

Unfortunately, posts of qhy cameras "acting up" are a bit too common. Usually it's firmware, driver or cable related. When I was in the market for a new astro camera, I came across several of this kind of issues. But that was almost 2 years ago, and I was mainly interested in those related to Linux. Otoh, qhy cameras can also produce stunning images. I hope you can get this sorted out.

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Another 'obvious' thing to check (this has caught me out before):  is there power going to the camera, i.e. through the power adapter box? 

In the past I have forgotten to switch on power to the QHY power adapter box -  in this situation the camera still responds to software but the image returned is blank.

 

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If you bring the camera indoors and aim it at the ceiling with no scope attached does it show anything? Try a 1second looping capture at 4x4 bin for fast download and wave your hand Infront of the camera....see anything?

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58 minutes ago, martin_h said:

If you bring the camera indoors and aim it at the ceiling with no scope attached does it show anything? Try a 1second looping capture at 4x4 bin for fast download and wave your hand Infront of the camera....see anything?

Yes it will darken if you put your hand over it. Gain and offset 13 and 131. I can't figure out the correct way to set these either as the chinglish instructions are poor.

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36 minutes ago, Stu Wilson said:

Yes it will darken if you put your hand over it. Gain and offset 13 and 131. I can't figure out the correct way to set these either as the chinglish instructions are poor.

Gain and offset are fine adjustments. The last time I set mine they were 13 and 118 respectively. They basically just set the dynamic range. There are clear instructions in chapter 3 - QHY8L Camera Manual.pdf

Binning will let you get a brighter image quicker for focussing but don't forget to set it back to 1 for actual images - and make sure the image download speed is slow for image acquisition otherwise the quality will be poor.

Louise

 

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43 minutes ago, Thalestris24 said:

Gain and offset are fine adjustments. The last time I set mine they were 13 and 118 respectively. They basically just set the dynamic range. There are clear instructions in chapter 3 - QHY8L Camera Manual.pdf

Binning will let you get a brighter image quicker for focussing but don't forget to set it back to 1 for actual images - and make sure the image download speed is slow for image acquisition otherwise the quality will be poor.

Louise

 

How do I set them properly in English rather than the dodgy version on their website/download?

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1 minute ago, Stu Wilson said:

How do I set them properly in English rather than the dodgy version on their website/download?

It's in plain English in the document I attached. In any case, having less than optimal values won't stop you acquiring an image.

Louise

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Also there is confusion about the offset setting it used to be between 500 and 1000 mine always gave the message offset to low at those vaules using ezcap,In the latest instructions anywhere between 500 and 3000 is ment to be ok.

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26 minutes ago, Stu Wilson said:

The confusing bit or maybe where something's wrong when you remove the lens cap and point at light your supposed be aiming for 60000 to 65000. I'm getting around 6000 to 10000.

Are you doing that during the day? That would probably be the best time :) Point at an even part of the sky. The idea is that the gain is sufficient to turn all 16 bits of data in to ones - 2^16= 65536 = 65535 counting from 0. So you want to get to just under this value. Make sure the image download speed is 'slow' as 'fast' might not be accurate enough.

Louise

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2 minutes ago, Stu Wilson said:

I'll try again later Louise but the point im making is with the gain adjusted right up to full I was only getting 6000 to 10000 around 55000 off the mark. This was pointing at white screen

Probably not bright enough or not long enough exposure.

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I just had a quick go with mine. It's not connected to a telescope but just making do... :)

Here is screen grab:

qhy8l_gain50pc.png.8c8f7c91e66775f1648a0b65c5ae84a8.png

I did a daylight exposure of 3.6s and adjusted the gain until the Max value was just under 65535 (gain =7). As I mentioned before it's a 'fine adjustment' for dynamic range and the default gain = 0 will still give you a good image.

Louise

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Ok tonights run down.......

Tried in daylight. With lens cap on I get somewhere in region of correct numbers.

Lens cap off either scope or no scope maximum gain the max reading I could get was around 8000. 

However. Very high clouds around tonight but could make out a very dim Vega in preview or focus with gains around 52 and offset 140 exposure up to 3.5 secs

New leads and clip from Bern haven't made a difference except another 40 or 50 quid that may as Well of been thrown to the wind.

I'm thinking this has got to go to China. Only thing really putting me off is will it get there will it be fixed and will it make it back. I'm gob smacked there is nowhere in this country can help check or repair these things but several places are happy to take a small fortune to sell you one.

Anyway the conclusion at this point is wait for a positively clear sky to try one last time and then send to China.

One last thought was trying old drivers but I'm not sure.............

Clear skies please......

Stu

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Can you do what I did above with the camera removed from the scope and in the daylight to check the gain? When you were doing it was there anything in the optical path? I take it you are connecting the camera via a T2 or M48 connection? I doubt there's anything wrong with the camera. Have you tried using the scope + qhy8l during the day on a distant object?

Louise

ps can you do a daytime screen grab the same as my one with the same settings?

Edited by Thalestris24
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