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Cheap starter camera find!


Carl Reade

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Nice work Johnno.  :smiley:

Hard to tell from those pics but the sammy seems to show better detail, but that could be due to focus, or scopes.

Look at the leaves on the tree. In the sammy you can make out individual leaves.

In the CR6 they are more a blur. But the woodgrain in the window frame shows fine detail in both cameras.

The only real test will be using the same scope for both cameras on the same object. A bright DSO would be good.

Don't have them both at the same settings because one camera may need more or less of white balance, or Integration etc. Just push each one to its own best settings and see which one comes out with the best Live image.

For a really cheap camera the CR6 is looking good so far. But focused and adjusted on a DSO will be the true test.

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yes its a bit hard to get the focus spot on, you only have to touch it slightly and it goes off, was using a c mount lens,

What I was trying to do is to see which one was letting more light in, both with the same settings

I did another test with the lens cap on to look for hot pixels, and boy they were plenty of them, more than the Sammy, but I didn't take a snap of it. might do one later. I think this needs some serious cooling

I'll be using this camera for wide field, just bought a 200mm M42 lens and a C mount adapter off flea bay for a grand sum of £17.87p :grin:     I bet its a load of rubbish

woh.. I have a edit button now.

has anyone found out what that photocell actually does? and what effects it has

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Johnno,

Please see attached image - the bright light is the top light on a radio mast, the dark area at the base of the image is my neighbour's roofline but what are the diamonds? - Are they those hot pixels?? The image was taken from indoors - temp approx. 22 degrees through an open door some 4 mtrs away. (one image shows exposure detail)

Cheers

Diamonds no scr detail.bmp

CR6 diamonds.bmp

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Nibor, my guess is that they are warm pixels.

Hot pixels are much brighter and look like small pixelated stars, whereas warm pixels look like what you have.

The difference is Hot Pixels will always show up. Warm pixels can be reduced by cooling.

Dead pixels are black.

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Whats the best way to check the pixels?

what I've done is set shutter to manual at 1/50 and X 512 and left it running for about 25 mins with the lens cap on. 

is this the correct way of doing it?

the sammsung as a cooling fan

post-24363-0-57541600-1381580569_thumb.g    post-24363-0-67300300-1381580585_thumb.g

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Yes Johnno, 

just leave the lens cap on and run the camera for about 5 minutes with the gain on high. That is plenty of time for the chip to get hot.

Then look for bright, dull, or black pixels.

Dull are OK. Bright ones are the ones you don't want to see.

Then run it for another 5 minutes with the gain on low and see if they almost disappear. The dull ones should (hopefully).

Cooling will help when using the camera . Also, keep the gain on low to medium, and saturation on the lower side. Sliding the Saturation slider all the way up makes them show up even worse.

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Yes Johnno, 

just leave the lens cap on and run the camera for about 5 minutes with the gain on high. That is plenty of time for the chip to get hot.

Then look for bright, dull, or black pixels.

Dull are OK. Bright ones are the ones you don't want to see.

Then run it for another 5 minutes with the gain on low and see if they almost disappear. The dull ones should (hopefully).

Cooling will help when using the camera . Also, keep the gain on low to medium, and saturation on the lower side. Sliding the Saturation slider all the way up makes them show up even worse.

 I had  AGC off  SSDR off   DNR3 off on both cams

next time I'll check at different ''X'' settings

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What constellations that john....looked everywhere can't find it....lol only kidding. ...think its a Peltier job on this cam...pretty bad mid to long intregation. ..nice massive mod then guys...great challenge wish I had got one...Davy

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Counted 14 wires connecting camera board to the rest. A HDMI lead contains 18. With this one it would be possible to seperate the front end from the body using HDMI screw terminals and a HDMI lead allowing an easy cool mod, but this is another thread..... :grin:

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Carl,

I have just tried the same test (I am assuming x512 / AGC off / DNR off) and get similar results - camera indoors ambient temp 22 degrees. BUT - With the AGC to low and DNR at 32 the image seems to practically uniform dark after a total of 45 mins with the lens cap on.(see attached).

This seems to show that the electronics are doing their job as these AGC / DNR settings would normally be used in DSO work  - am I missing something here? Have I misunderstood the hot pixel test and the need for cooling?

Anyone else any thoughts??

CR6 x512 agc low DNR 32.bmp

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