QHYCCD

QHYCCD Camera Hardware Development => New Camera Information => Topic started by: xs_man on March 29, 2016, 04:05:07 pm

Title: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on March 29, 2016, 04:05:07 pm
I've recently received my new QHY5III 174 M (monochrome uncooled version)
for testing. Of course, clouds and rain are back, no clear skies for next 2 weeks
or more ! So sorry no pictures.... Just hope it will quickly change !

It's a compact camera which comes with a CCTV lens 50 mm F/1.4. Cool to
cover a large field of view in sky (Constellations with short exposure for example) !
But my main goal with QHY5III 174 is to use it for deep sky objects with short
exposures (let's say 1 to 5 seconds) with a fast telescope (F/D 4 to 6). As Emil
Kraaikamp succesfully do for example with same sensor. ;)

http://www.astrokraai.nl/viewimages.php?t=y&category=7

The big pixels (5.9 microns) and a good sensitity in visible light are perfect for this task.
Main drawbacks are high readout noise and dark current of IMX 174, considering that
amp-glow is greatly reduced by the camera if exposure is more than 7 seconds.
Of course the cooled version reduces the dark current greatly.


1- Frame rate tested with SharpCap 2.8.2325 (90 seconds .Ser capture; 1 ms;
------------------------------------------------------------------------------------------------
Gain 50; Speed 1; USB Traffic 0) :
-------------------------------------------------

Full frame : 133 fps (8 bits); 67 fps (16 bits)
1600x1200 : 136 fps (8 bits);  70 fps (16 bits)
1280x1024 : 158 fps (8 bits);  87 fps (16 bits)
1024x768 : 208 fps (8 bits);  122 fps (16 bits)
800x600 : 263 fps (8 bits);  155 fps (16 bits)
640x480 : 324 fps (8 bits);  191 fps (16 bits)
320x240 : 602 fps (8 bits);  355 fps (16 bits)


Binning 2x : 960 x 600 : 111 fps (8 bits); 78 fps (16 bits)

PC with Intel Core I7-4770 CPU @ 3.4 Ghz - 16 Mo RAM DDR4
Windows 7 64 bits - SSD Samsung 840 EVO 500 Mo.


2 - Noise measured with Isis software and Darks/Offsets/Flats :
--------------------------------------------------------------------------------
Ambiant temperature was near 16 or 17°C.

Gain = 0
--------------
Gain : 0.459 e-/ADU
Readout noise (RON) : 5.35 électron(s)
dark current: 3.3896 e-/s

Gain = 20
---------------
Gain : 0.148 e-/ADU
Readout noise (RON) : 3.91 électron(s)
dark current: 4.1079 e-/s

Gain = 40
----------------
Gain : 0.046 e-/ADU
Readout noise (RON) : 3.39 électron(s)
dark current: 4.3721 e-/s

Gain = 60
----------------
Gain :  0.014 e-/ADU
Readout noise (RON) : 3.24 électron(s)
dark current: 2.7894 e-/s

Gain = 80
----------------
Gain : 0.004 e-/ADU
Readout noise (RON) : 3.14 électron(s)
dark current: 2.8362 e-/s

Gain = 100
-----------------
Gain : 0.002 e-/ADU
Readout noise (RON) : 2.81 électron(s)
dark current: 1.6564 e-/s



3 - Cooled or uncooled ?
-------------------------------

The good question with such a sensor !

For planetary/lunar/solar use and exposures under 1 second, no need of cooling.

For deep sky short exposures between 1 to 10 seconds, I think I would avise cooling
as IMX 174 sensor has a high level of dark current. It becomes interesting to reduce it.

For deep sky long exposures greater than 10 seconds, cooling can't be by-passed,
 it's necessary to have it.

Anti-amp glow electronic system seems to work nicely on darks but the best
test will be done on a real deep sky target.

TO BE CONTINUED.....

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 02, 2016, 12:08:47 pm
Hi all,

BREAKING NEWS ! ;D

First, here is a picture of the package I receive for testing : the
camera, cables and nose in a nice metal box. In 'extra-bonus' a little
50 mm CCTV lens.

(http://www.webastro.net/upload/images/1359-1459616375.jpg)

I tried the little CCTV objective as the sky is completly
covered. It's just to have an idea of what the frames will show for
planetary imaging use with different Gain values. As we mostly use high values,
let's say between 70 and 100%, the horizontal banding is easily visible. So
it's important to capture maximum number of frame to remove it when adding the
subimages. But for those who use or have use a PL1-M in the past (as me !)
the images delivered by IMX 174 are clean in comparison ! I'm not worried about
it lots of wonderfull images have been taken with this sensor.

(http://www.webastro.net/upload/images/1359-1459616518.jpg)

Second part was to show the effect of cooling the camera and the amp glow
reduction. I have the uncooled version and I would have better ask for cooled
version ! But too late, so I put the camera in waterproof bag and to put
ice cubes arround the camera. Ambient T° was 16 to 17°C. So I would say
the sensor temperature was decreased by nealy 15°C. Efficiency is limited
compared to Pelletier cooling of sensor.
But it's enough to clearly say :
- Cooling has visible effect from 3 seconds exposure,
- Amp glow is visible for 3 and 5 second exposure darks (right side of frames)
  and is greatly reduced for 10 seconds. So yes, amp glow reduction works fine ! 
 
(http://www.webastro.net/upload/images/1359-1459616576.jpg)

Here a test in longer exposure  :
 
(http://www.webastro.net/upload/images/1359-1460839134.jpg)
Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 06, 2016, 05:34:16 pm
FIRST IMAGES WITH QHY5III 174 M :

Hi All,  ;)

A gift from the sky last night : a half of the night without Clouds !
Bad seeing and a few wind so I directly forget Jupiter and tried deep sky
objects with short exposures.

Here I use my 12" F/D 5.3 Nextonian on EQ-6 Mount, and the QHY5III 174 M (uncooled)
without any filter to gain maximum light. Each frame is exposed 2 seconds only.

I tried M65 and M104 galaxies. But I have only 613 frames for M104, clouds comes
too quickly to finish the session.
     
16 bits mode - frames in TIFF format
M66 : 2082x2 seconds. Gain = 80%
M104 : 613x2 seconds. Gain = 75%

(http://www.webastro.net/upload/images/1359-1459981564.jpg)

(http://www.webastro.net/upload/images/1359-1459981601.jpg)

With enhanced background  (horizontal pattern is visible, need more frames
to reduce it more) :

(http://www.webastro.net/upload/images/1359-1460121535.jpg)

Conclusion : the camera works fine for this technique ! I'm happy !

Best Regards.

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 09, 2016, 03:43:59 pm
2 new images from last 7 to 8 April 2016 night.
Same setup : Orion Optics 300 mm F/D 5.3  on EQ-6 mount
+ QHY5III 174 M without filter.

M96 : 3074 frames of 2.5 seconds + 580 darks
M64 : 3035 frames of 2.5 seconds + 388 darks

Albéric

(http://www.webastro.net/upload/images/1359-1460222201.jpg)

(http://www.webastro.net/upload/images/1359-1460222300.jpg)
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: einari on April 10, 2016, 04:41:09 am
That is kind of lucky imaging.
The M64 specially looks cool.
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 10, 2016, 12:30:46 pm
Here is a little summary of my technique of short exposures imaging applied to Deep Sky
Objects - DSOs. It's a mix between 'Lucky Imaging' technique for planetary objects and
long exposure for Deep Sky Objects.  ;)

Main advantages to use short exposures for DSO are :
----------------------------------------------------
- No need of auto-guiding system which may be difficult to calibrate,
- No need of super heavy, super expensive or super sturdy mounts,
- A 'planetary setup' is enough,
- Shorter exposures = less atmospheric disturbance effects on each frame.
  So a better resolution can be expected in good or even in medium seeing
  conditions. 

Main drawbacks :
----------------
- Few light compared to long exposure so the limit magnitude is lower than
  traditional long exposure mode. In fact the gap is not as huge as we could
  expect if adding a lot of frames. 

What are the limits of 'short exposure' ?
-----------------------------------------

Good question...

For planetary target, limit is Neptune with an Infra-red filter, let's say
0.5 second in worst case. In most cases, less than 100 ms.

For DSOs, few objects (some bright planetary nebulas, open clusters or glubular
clusters) could be imaged with 100 to 500 ms exposition time with the most recent
sensors.
For galaxies, lower limit exposure time will be 1 second to... 'more'. And 'more' is
quickly limited by mount tracking, atmospheric disturbances, wind and dark current
of the camera when uncooled. For me a realistic value for 'more' is 5 seconds.
So short exposure for DSOs : between 100 ms to 5 sec.

As you can see on my first post, for uncooled IMX 174 which have high dark
current it's better to decrease the upper limit to 3 seconds.   


Frames acquisition :
------------------

First, align correctly your mount as done for long exposure.

I currently use a software for planetary/lunar/solar acquisition like SharpCap 2.8
and when it will be released, Firecapture. 

Use only 16 bit Image format and save as TIFF or PNG.
Use high ain value : 60 - 90. Higher than 90% will give very noisy frames.
Less than 60%, the readout noise will increase. 

To reduce the noise pattern that may appear in background of final image, let the
target move a little bit on the sensor. With the Hand Pad, or if your mount has a
bad Periodic Error curve, it will do the job.


Don't forget to make 'Dark' images after choosen target imaging session, as done
for DSO with long exposure. The more frames, the best.
I don't use Bias nor Flat with IMX174. For bigger size sensors I guess that Flat
will be necessary. 

Processing :
------------

Before registration, I manually sort out the good images from the bad ones.
I don't use automatic sort out. Of course it takes lot of time but I'm
sure it's efficient ! You can use automatic process if you prefer.


For registration, I use Registax 5.0 in monopoint mode ('Aligment Method' : 'Default').
An other solution is Autostakkert 2.6 which have optimisation options to reduce
horizontal noise pattern like IMX 174.

For post-processing I use Iris and Photoshop to adjust the curves and contrast.

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: Wagner Trindade on April 11, 2016, 08:48:30 am
Here is a little summary of my technique of short exposures imaging applied to Deep Sky
Objects - DSOs. It's a mix between 'Lucky Imaging' technique for planetary objects and
long exposure for Deep Sky Objects.  ;)

Albéric,

Very nice and straight forward procedure. Already copied it to my files.
Thanks for sharing.

Regards,
Wagner
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: riklaunim on April 11, 2016, 11:41:12 am
How does amp glow looks like on longer exposures?
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 16, 2016, 03:43:24 pm
Thanks Wagner.  ;)

How does amp glow looks like on longer exposures?

Hi Piotr,

I've added longer exposure darks : 30 sec, 60 sec, 120 sec.
As you can see, amp glow remains very limited even with 120 seconds.

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on April 21, 2016, 01:16:04 pm
New picture taken las 18/19 of April.

This time I use my 16" F/D 4.5 Newtonian. Obviously the optical distorsion
are more visible on the stars. I need to buy a field corrector.
M57 Whirlpool galaxy.

2915 x 2.5 sec exposures + darks.
QHY5III 174 M without filter

(http://www.webastro.net/upload/images/1359-1461260207.jpg)

Albéric
Title: Moon images
Post by: xs_man on April 24, 2016, 02:01:13 pm
Here are 3 new images with QHY5III 174 M on Moon last 18/19 April 2014.
16" F/D 4.5 Newtonian + 5x barlow + yellow filter.
Medium to bad seeing conditions.

10000 frames for each captures.

Schiller : 1483 frames selected
Unknown crater : 690 frames selected
Sinus Iridum : 1186 frames selected

Processing : Avistack + Photoshop.

(http://www.webastro.net/upload/images/1359-1461522414.jpg)

(http://www.webastro.net/upload/images/1359-1461522345.jpg)

(http://www.webastro.net/upload/images/1359-1461522287.jpg)

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on May 10, 2016, 01:20:12 pm
New pictures with my 16" F/D 4.5 Newtonian. QHY5III 174 M without filter
M63 : 3360 x 3 sec exposures + darks.
M100 : 3350 x 3 sec exposures + darks.
NGC4631 : 3690 x 3 sec exposures + darks.

(http://www.webastro.net/upload/images/1359-1462716815.jpg)

(http://www.webastro.net/upload/images/1359-1462716928.jpg)

(http://www.webastro.net/upload/images/1359-1462830499.jpg)

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on May 18, 2016, 03:15:29 pm
I've added new 5005 RAW images to my previous M51 (night 16 th of May 2016).

M51 with Newtonian T400 + QHY5III 174 M uncooled without filter.
No field corrector (I know it would be better to have one !)
5005 x 2 sec + 2915 x 2.5 sec

It's my best image until now :  ;)

(http://www.webastro.net/upload/images/1359-1463601936.jpg)

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: einari on May 19, 2016, 01:24:52 am
Must try this next season with my 174MC Cool.
Btw, do you filter your images (ie AstroArt can filter out depending on FWHM and roundness) ?
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: xs_man on May 22, 2016, 11:59:33 am
Must try this next season with my 174MC Cool.
Btw, do you filter your images (ie AstroArt can filter out depending on FWHM and roundness) ?

Hi,

I don't use software to sort out the best frames.
But I sort out all frames one by one with my own eyes.
I know that people think I'm crazy but it gives the best results !

Albéric
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 09, 2016, 05:45:48 am
Hello,
I have tested the QHY5III 174C for deepsky and my results are sometimes good and sometimes the pictures has a lot of aleatory stripes like in the attachment picture. I don't know why this happens.

Does anybody know the reason of those stripes?

This picture is the result of 400 lights, 400 darks a 400 bias at 10 sec, 100 offset, 70 gain, adquired with Sharpcap and stacked with DeepSkyStacker. Stacking with Pixinsight gives the same result.

Thank you in advance,

Andres
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: SteveInNZ on August 09, 2016, 02:48:07 pm
Andres, Was this taken with a guided mount ?

Steve.
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 10, 2016, 04:54:55 am
No Steve, but I made tests with autoguide and there is no difference.
But the fabolous pictures posted below weren't adquired with guiding, isn't it. This is the advantage of this technique.

The tests I did were taked from my house and I can't see Polaris from here, but I made aligment to Polaris with an option in the mount software. This aligment is not as good as the true polar aligment, so I think this can be the reason.

Yesterday I can go out and I made several tests with true Polar aligment using the Polemaster and without guiding, and now I am procesing them, but I have seen that there is drifting between the individual frames because periodical error, so it can be possible that the effect happen again.


When I process the new tests I'll put the results here.
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: terrylovejoy on August 10, 2016, 06:12:28 am
Andres,

The stripes are typically caused by errors in calibration, eg if a dark frame is used that was at a different temperature, gain or exposure length to the light frame.

Terry
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 10, 2016, 06:55:16 am
Thank you Terry.

Logical thinking goes to you said about error in calibration, but I always make darks and bias in the same session after making all the light frames and with the same gain, offset and exposition time that light frames.


Could be another possibility the calibration error?

Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 10, 2016, 01:02:04 pm
Here are the result of yesterday session.
As you can see, the stripes are there. >:(

I'm sure that darks and bias are made in the same conditions that lights. I am disappointed, I bought this camera for applying the technique described in this topic, but I can't get good results.

I'm afraid that I have only a very expensive camera for autoguiding and planetary.  :'(
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: einari on August 11, 2016, 02:13:36 am
If it is uncooled camera then dark temperature can change during imaging session making darks uncorrect.
You could try leaving darks out of calibration - see if that helps.
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 11, 2016, 03:12:54 am
Sorry, but my english is not very good. I don't understand the phrase "You could try leaving darks out of calibration".
Do you mean that try process the images without darks?
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: einari on August 11, 2016, 04:17:33 am
Yes.
Then you can see hot pixels unless you use suitable stacking method - median or better some sigma rejection (= clipping).
If you are using DeepskyStacker there's a hot pixel removal option (Stacking - Cosmetic):
http://deepskystacker.free.fr/english/userguide.htm
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 11, 2016, 11:27:32 am
I have attempted with the Stacking-comsetic option and the result is that the stripes smooth a little, but the image too, and the result is worst.

I have substrated one light with one dark and one bias, and results an image without hotpixels, but I suppose that the hotpixels are not fully eliminated.

I can't found what is the problem. The camera was working for three hours, it's possible that in the first captured frames the temperature was lower, but after a time I suppose that the temperatura stabilized itself and some of the objects captured would be ok.

I am thinking that my camera is not able to do the described technique in this topic. I would like Albéric see my results and tell me why I can't captured images as good as his fabulous galaxies.



Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: easybob95 on August 12, 2016, 01:51:54 am
Hello ajs,

maybe your camera have a problem ... or not.

The problem happens some time with very good beta tester is that they have very good results with very heavy treatments and it is hard to have the same results.

So, it is quite dangerous to choose a camera only considering the results very good testers have.

Alberic is very very good and i know he made very heavy treatments with IMX174 uncooled camera because of the strippes and the ampglow.

Standart astrophotographer will have difficulties to gain such results.

Alain
Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: ajs on August 12, 2016, 03:41:37 am
I have got acceptable results, at least without stripes in two or three times, but the conditions are quite diferent. The exposition time 20 s, and gain less than 60. You can see tehm in the attachement files. (Ignore the processing of the images, are the first images I process with Pixinsight)

Alain, you can are right and that is because I am asking in this forum and I am grateful to all you for your help.

Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: easybob95 on August 12, 2016, 04:37:09 am
IMX174 uncooled cameras are quite hard to manage. IMX174 is a very interesting sensor but it may needs heavy treatments.

Alberic had some big difficulties to manage the uncool version and despite his great experience of treatments, he did not always succed to get very good results.

The cooled version of IMX174 is easier to manage but it is also complicated to manage stripes.

As for me, i did not buy an IMX174 sensor based camera because this sensor is to difficult to manage (i don't talk about planetary imaging). I had the miniCAM5F experience which was already quite hard to manage (but much easier then IMX174 camera).

When Sony will bring us a new IMX174 sensor with IMX290 quality, it will be very good for us.

Alain

Title: Re: First evaluation of QHY5III 174 monochrome (uncoled)
Post by: SteveInNZ on August 12, 2016, 04:41:31 pm
The appearance of the noise in the Eagle Neb is a consequence of unguided imaging with an alignment error. The noise itself is from the things you know about (thermal noise, gain, etc) but the pattern indicates drift over the total imaging time.
Each sub doesn't have any noticeable drift that would make the stars oval but over the total time, the stars have drifted relative to the absolute position on the sensor. When the stacking program aligns the frames on the stars, it effectively moves the noise by the drift amount.
Obviously, you'll get the the greatest benefit from reducing the noise in the first place but better polar alignment will remove the pattern which is hard to remove with noise reduction techniques.

Steve.