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Sony ICX694 or Kodak KAI-4022 for C-8 EdgeHD?

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#1 Peter in Reno

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Posted 31 July 2012 - 11:14 AM

Sony ICX694:

Very sensitive (QE 77%)
Very low noise (may not require dark subtraction)
Very low read noise (5 electrons)
Not so great full well capacity (20,000)
Image scale may not match to C-8 EdgeHD optics due to 4.54uM pixels
Cameras: Atik 460EX or SXVR-H694

Kodak KAI-4022:

Not very sensitive (QE 55%)
Little noisey (may require well temp regulated dark subtraction)
High read noise (11 electrons)
Very good full well capacity (40,000)
Image scale may match to C-8 EdgeHD optics due to 7.4uM pixel
Cameras: Atik 4000 or QSI 640

If Sony had same pyhsical size CCD chip as Kodak's, I would easily pick Sony due to high sensitivity. I am not sure if image scale matching to optics is critical since I have A-P Mach1 GEM with low PE and backlash so small image scale may not be an issue. I have seen many great images taken with KAI-4022 as well as ICX694 so I am having a hard time deciding. Price or budget not really an issue but I have principle.

If both CCDs result equally great images, I would probably pick QSI640wsg due to simple design with built-in filter wheel and OAG plus only one USB cable and one power cable is needed as opposed to camera plus external filter wheel. QSI is the most expensive but that's okay.

Which CCD would you pick for C-8 EdgeHD at 2000mm focal length or 1456mm focal length when F/7 focal reducer becomes available.

Thanks,
Peter

#2 blueman

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Posted 31 July 2012 - 03:13 PM

Well, the image scale of the Kodak chip would be 1.09" at F/7, which is pretty nice.
With the Sony, it would be more like .65-.7", which is doable, but harder.
I think a lot would depend on the seeing where you will use it. A good match to that as well as the optics will give you the nicest images. If you get better than 2" seeing most of the time you could probably do either one with good results.
Blueman

#3 Richard Crisp

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Posted 31 July 2012 - 06:57 PM

Sony ICX694:

Very sensitive (QE 77%)
Very low noise (may not require dark subtraction)
Very low read noise (5 electrons)
Not so great full well capacity (20,000)
Image scale may not match to C-8 EdgeHD optics due to 4.54uM pixels
Cameras: Atik 460EX or SXVR-H694

Kodak KAI-4022:

Not very sensitive (QE 55%)
Little noisey (may require well temp regulated dark subtraction)
High read noise (11 electrons)
Very good full well capacity (40,000)
Image scale may match to C-8 EdgeHD optics due to 7.4uM pixel
Cameras: Atik 4000 or QSI 640

If Sony had same pyhsical size CCD chip as Kodak's, I would easily pick Sony due to high sensitivity. I am not sure if image scale matching to optics is critical since I have A-P Mach1 GEM with low PE and backlash so small image scale may not be an issue. I have seen many great images taken with KAI-4022 as well as ICX694 so I am having a hard time deciding. Price or budget not really an issue but I have principle.

If both CCDs result equally great images, I would probably pick QSI640wsg due to simple design with built-in filter wheel and OAG plus only one USB cable and one power cable is needed as opposed to camera plus external filter wheel. QSI is the most expensive but that's okay.

Which CCD would you pick for C-8 EdgeHD at 2000mm focal length or 1456mm focal length when F/7 focal reducer becomes available.

Thanks,
Peter


i use the KAI4022 with great success on both the AP180EDT f/9 and the Stinger 450mm f/12.6 (reduced to f/7.4) classical cass.

Mine is in the FLI ML4022 configuration. What's with this fixation on QSI? You get yesterday's technology finally today after waiting years for it. The first generation was a joke with the QSI583 taking 23 seconds for a readout and something like 35C worth of cooling on a good day. Why on Earth would anyone subject themselves to such torture and then have the chutzpah to say that they *like* it?

I just don't understand the thought process...

My ML4022 (made in 2008) cools at least 55C from ambient, downloads in 2.2 seconds and is remarkably quiet (9.1e- @2.2 sec readout).

Additionally one can open the mechanical shutter and use it to take video or to take arbitrarily short flats... That's how I use it with the big Truss Tube Cass...

but I digress:

example images:

1620mm FL:
http://www.narrowban...ao3he2_page.htm

http://www.narrowban...s2hao3_page.htm

http://www.narrowban...s2hao3_page.htm

http://www.narrowban...liumII_page.htm

http://www.narrowban...n2hao3_page.htm


3366mm Focal Length:
http://www.narrowban...ml4022_page.htm

http://www.narrowban..._camel_page.htm

http://www.narrowban..._camel_page.htm

http://www.narrowban...cs4_ha_page.htm

http://www.narrowban..._camel_page.htm

http://www.narrowban..._camel_page.htm


if anyone is interested, I have a full photon transfer characterization report of the camera available both in binned 2x2 and binned 1x1 mode

it is in the back of this:

http://www.narrowban...est_version.pdf

The camera characterization appears starting on page 40. The rest may be of interest to those that are curious about the impact of F/Number on SNR and how to go about quantitatively analyzing images for SNR etc after the fact.... how else can you know if you are improving or worsening things if you don't have an objective measurement methodology?

#4 vpcirc

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Posted 31 July 2012 - 08:12 PM

Peter with your skies and that focal ratio, go with larger pixels. Those small pixels won't produce very good resolution with the high focal length and very light polluted skies. I understand liking the QSI with the built in filter wheel, and OAG. The other issue is OSC or mono? Sony builds the best OSC chips, but size is very limited on mono. If you're going mono, I think you would make a good choice with the QSI 640 wsg-8. You may want to venture into NB and produce more images per month. You can keep with the smaller 31 mm filters and that built in OAG goes great with the Edge. Make sure to get the right adapter based on which guide camera.

#5 Peter in Reno

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Posted 31 July 2012 - 09:28 PM

Sony latest ICX694 is available in both mono and color and I am interested in the mono version.

I didn't realize light pollution can have negative impact with smaller pixels and long focal length.

I am mostly concerned with dark and read noise from Kodak chips. Kodak's dark current is 0.01 electrons/second at -20° C or 0.1 electrons/second at 0° C and Sony's is less than 0.002 electrons/second @ -10C. Sony's read noise is half of Kodak's.

Sony CCD appear to be a better chip but unfortunately it may be the wrong size for my scope. I have seen some sample images taken by one of CN'er using C-11 at F/6.3 (0.6 arcsec/pixel) and Sony's ICX694 and they look pretty good. I could always use binning but the resolution would be much smaller.

Peter

#6 Konihlav

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Posted 01 August 2012 - 02:01 AM

Richard Crisp: first of all, I really appreciate your comments/posts Richard and your papers require a lot of effort (and time) for me to find any kind of "bug" in them or something that would bring up the discussion if something is half-explained or not very clearly described...

You are certainly right about QSI (I have my reasons why that company is not my favorite - but I am different, not normal) and about blindly-loving (prefering) one manufacturer over other.

I, personally, distinguish at first level between CCD chips and later between manufacturers.

This brings my question on you:
- why "the hell" :) you, as a smart narrow band imager, can ever consider KAI-4022 chip to purchase? it would be OK with me if you say only for LRGB work (as that's the reason I own the bigger brother 11002). The thing is that with this interline Kodak having QE in Ha around 31% means that if I frame an object I have to take 60 seconds sub(!) binning 4x4(!) and highly stretch the image to see what am I imaging !!! on the other side, if I used Atik 314L+ (ICX285) then I put 10 seconds preview, normal stretch, and I saw exactly nice and clean H-a image of my target that I easily framed... so the QE sensitivity and image cleaness of small SONYs is unbelievable...

- why are you using "some" Custom Scientific filters??? I have seen some plots and found them very "bad". I don't understand the reasons, but I am willing to learn your experience and think about it :) hope you enlight me :)

all best
Pavel


Peter in Reno - if you wait a month or two (my new (yet another) Atik460EXM should arrive every minute (today)) I show some images taken with EdgeHD11 and Optec F/6.3 and ICX694. I plan to do some lucky imaging, and working on a new OAG setup for shooting planetary nebuas at bin2x2 resulting in image scale 1.06" or so... should be a killer setup for PNs.

#7 vpcirc

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Posted 01 August 2012 - 03:58 AM

Peter, you shouldn't bin luminance. I just went through this whole exercise a year ago and learned a lot. Matching the camera to the OTA is very important to do to get the best results based on your conditions. If you have great skies in a dark location, the arc sec per pixel doesn't matter nearly as much. I wanted a larger Sony mono chip, but they weren't available. I spent hours with Kevin Nelson from QSI and with Tim Puckett at Apogee learning. You might want to contact the reps. Both are imagers as well as pros and understand most of this far better than most of us do on the forum. To Richard if it's not an FLI its no good. I would contend Apogee builds just as quality of a camera, but many people don't have the budget for either. When I had my QSI, it performed flawlessly. The WSG series is a great value for the package. They did not carry the larger chip I wanted so I had to move to another company.

#8 Leonardo70

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Posted 01 August 2012 - 04:05 AM

Hello Peter, maybe not the most competent person to tell you but if I were you I'd take a CCD sensor with 4022. I got to use it a few times and I was fine.

All the best.
Leo

#9 Konihlav

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Posted 01 August 2012 - 04:25 AM

Leo, did you already test your new Atik 428EXM on your telescope(s) ??? I am very curious on the output :)

#10 Leonardo70

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Posted 01 August 2012 - 05:45 AM

Not yet ... :-)

#11 Richard Crisp

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Posted 01 August 2012 - 08:06 AM

To Richard if it's not an FLI its no good. I would contend Apogee builds just as quality of a camera, but many people don't have the budget for either. When I had my QSI, it performed flawlessly. The WSG series is a great value for the package. They did not carry the larger chip I wanted so I had to move to another company.


that's a gross oversimplification and is not correct

my point is simple: QSI is lagging way behind... why pay top dollar today for something that *might* be bug free when the same capabilities and greater parametric performance can be purchased 3 years ago... which one do you think is more stable?

to me all the QSI has offered is SBIG like parametric performance (lousy cooling, poor download speed and no better noise results than their competitors that work better)

unfortunately most people that buy things do so on the recommendations of people that know about as much about what they recommend as a cake decorator knows about tuning a rocket engine....

let's get one of these PRIZED QSI also-rans and do a thorough characterization and measure

1) read noise
2) full well
3) linearity
4) gain
5) PRNU
6) DSNU

and let's just lay it out for the world to see....

I say that the product is at best a middle of the pack performer.... better than that joke of a product they created (the joke is DEFINITELY on the purchaser) called the 583..... what a piece of trash that one is parametrically

if you have a good day you MIGHT get 35C cooling while you wait an eternity (23 seconds) for your twilight flat to download...

yes the joke is on anyone that spends their money on that POS

why would you expect anything different from them this time?

what brilliance does it take to combine an OAG with a camera? And what more brilliance does it take to get all excited about something you can make yourself by buying off the shelf parts?

you can buy from a trendsetting leader (FLI was first with the 16803, first with RBI management, first with 2 second downloads, first with deep (greater than 55C cooling) etc etc....

While the other guys are trying to figure out "how did they do that?" the leaders have moved on making newer and better things...


Speaking of bigger and better: where's the KAF16803 from QSI...... How hard is that? Well it took SBIG three years to put one on the market after FLI did it... QSI has been making promises (vaporware) for a long time... where's the beef?

You can buy from the guys that do it first, best and set the trends for others to follow... or you can buy from the copycats that still are unable to ship a big chip product after promising it for four years..... I think the choice is clear who is the technology leader... and why on Earth would you want to pay top dollar from an also-ran that only has a shiny blue box with an obvious combination of off the shelf parts as his differentiation... that and definitely lackluster parametric performance... your money, and your choice but you have to live with it once you spend the bux so you better know and like what it means to use a poorly cooling slow to readout camera...

and what does that mean?

1) slow to readout... better invest in an EL Panel ($100s) because you aren't going to be shooting any twilight flats using broadband filters with 23 second downloads..... and of course the spectral characteristics of an EL panel are NOTHING like that of the night sky...

2) 35C cooling (at best).... hoses, water, shooting darks at -10C for summer imaging.... great. what a wonderfully performing product :-(


yes PT Barnum was right: there's a sucker born every minute and a fool and his money are soon parted!

I just try to bring the facts to an emotional discussion.... I have the data, i can show you how to measure your camera so when you say you like it, you can at least know how well it is performing or not instead of basing your LIKE on color, form and fit and other such things that are actually IRRELEVANT to the perfomance in the application



#12 Vladimir Elvov

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Posted 01 August 2012 - 08:31 AM

Richard,

You are clearly biased and even if you have some point your prejudices are the first thing that stand out.

If you are advertising rocket engines to people without a degree in rocket science you need to behave as a cake decorator.

#13 Richard Crisp

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Posted 01 August 2012 - 08:56 AM

This brings my question on you:
- why "the hell" :) you, as a smart narrow band imager, can ever consider KAI-4022 chip to purchase? it would be OK with me if you say only for LRGB work (as that's the reason I own the bigger brother 11002).


For me the KAI4022 was ideal for my 18" Cassegrain:

1) using it at 3366mm I get an image scale of 0.45"/pixel and that goes well with my seeing in the 1.2-1.5" range.

2) using the electronic shutter I can take very short flats... 50msec is easy,so sky flats are no problem: even with a luminance filter. The truss tube design makes it impractical to take "tee shirt flats", and EL panel flats have too many issues...sky flats are the only choice.

For the flats: the 2 second downloads make this a snap... you get the exposure figured out... 50 vs 100 milliseconds.... and then you knock out flats 5-10 at a time... bang bang bang.... I can shoot an entire set of LRGB plus Ha/O3/S2 SKY FLATS in less than 10 minutes taking 20 flats per filter (with the exposure level tolerance frame to frame of less than 2%)....

can you do that with a QSI583?

On the QE, it isn't as bad as you make it sound... The pixels are the same pixels used in the KAI16000 and all other sensors with the 7.4 micron interline. A reduced QE simply means you take more exposures. However I can tell you that the number of additional exposures will be a function of the read noise and exposure parameters.

so you can be in a situation where you can get a better S/N in less time using a camera with a lower read noise despite a lower QE than one with a higher QE and higher read noise if the images are
1) low contrast (like nebulae)
2) signal buried in the read noise (like faint nebulae)

You cannot look at one parameter in isolation, you need to be able to quantify the entire imaging system if you want to optimize it.

#14 Richard Crisp

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Posted 01 August 2012 - 09:08 AM

Richard,

You are clearly biased and even if you have some point your prejudices are the first thing that stand out.

If you are advertising rocket engines to people without a degree in rocket science you need to behave as a cake decorator.


It isn't a matter of bias. It is a matter of 'been there done that'... when you have measured as many and used as many as I have you see clear patterns....

I can't change the facts...I align with those that make the best... you can do what you want but mischaracterizing my acting on cold hard facts as bias is simply an error on your part.


Also for the record I was NOT talking about advertising; I was talking about the testimonials I see recommending this or that product. The point was that the basis used to support the recommendations in many cases are irrelevant to the anticipated peformance in the stated application. Additionally the resume of qualifications of the person making the recommendation are as mismatched as a cake decorator being asked to tune a rocket engine.... in short the person has no clue where to start if the task is to put together a relevant, concise and factual comparison of the performance and operational tradeoffs of two or more proposed courses of action.

#15 Peter in Reno

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Posted 01 August 2012 - 09:15 AM

Rich,

I think you are a little behind and may have not read the QSI web site lately. Their 600 series cameras are quite different than 500 series cameras. The download speed is much faster and the cooling is up to 45C below ambient at 85% cooling power. Their download speed is now less than 7 seconds in high quality mode and 0.7 second in high speed mode. I really don't care for 7 second download speed during imaging session but 0.7 second for focusing will come in handy.

http://www.qsimaging...0-overview.html

Peter

#16 vpcirc

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Posted 01 August 2012 - 09:20 AM

Sorry Richard, you're a smart guy with understanding how chips work, your numbers aren't to accurate as far as the qsi is concerned. Peter lives 200 miles from me and has cooler nIght time temps than I do. I had zero problems achieving -35 in the summer, had no problem with sky flats, especially when using ACP. The QSI ends up being far cheaper with a built in OAG, and the dream of a built in filter wheel where the OAG sits in front of the filters preventing guide star problems. Having owned an SBig 8300 then a QSI 583, the QSI cooled better than the SBig. Sbig has cone out with a new line, so I can't comment on the STi series having not owned one. Other QSI owners should speak up and share their experiances. I would have purchased another, but they don't carry a large format chip that I wanted. I respect your opinion Richard, but I know Peter doesn't have $15k to waste on a camera.

#17 Peter in Reno

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Posted 01 August 2012 - 09:30 AM

I forgot to mention that I used to have QSI583csg COLOR CCD camera a while ago. The cooling was fantastic. The temperature set point was very stable and never fluctuate like my current SXVR-M25C does. I didn't like the camera mainly because the sensor was insensitive due to being color CCD instead of mono and was much less sensitive than my previous Orion StarShoot Pro. Yes, QSI583 download speed was quite slow but it's now faster in 600 series cameras.

I think QSI makes high quality CCD cameras.

Peter

#18 Vladimir Elvov

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Posted 01 August 2012 - 09:35 AM

Well Richard,

One cake decorator is Nik Szymanek (ccdland.net)
With all due respect to the links you posted I feel his images with QSI are more convincing.

Another well-known decorator is Craig Stark. He is happy with his QSI 540.

If their decorations make me feel like moving in a rocket I really do not mind spending some money on astro cakes.

I think with all your hard evidence you are missing a point.
People are looking for something as affordable as they can get and as performing as they can be pleased.

QSI is apparently somewhere in between. Atik 383 is cheaper but I was so frustrated with it that sold it as fast as I could.

Jumping to FLI after Atik is something I can't really afford if you add filter wheel and more expensive filters.

I'm really happy with QSI 683 and as Peter pointed out the problems you are referring to are fixed.

In short you may need to consider the reasons "normal" consumers like me have before dismissing us as idiots

#19 Peter in Reno

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Posted 01 August 2012 - 10:14 AM

Hello Peter, maybe not the most competent person to tell you but if I were you I'd take a CCD sensor with 4022. I got to use it a few times and I was fine.

All the best.
Leo


Hi Leo,

I have seen your fantastic images at your web site. It looks like KAI-4022 is a great chip.

How do you calibrate your images? Do you always use dark subtraction or is the dark noise low enough to use something like Bad Pixel Mapping? Do you need to take many dark subs (as much or more than light subs)?

I never use dark subtraction with my current SXVR-M25C (Sony CCD) and use Bad Pixel Mapping. Dark subtraction with Sony chip can actually be worse so I use BPM pretty successfully. That's partly why I was looking at Sony ICX694.

Thanks,
Peter

#20 Richard Crisp

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Posted 01 August 2012 - 10:17 AM

Rich,

I think you are a little behind and may have not read the QSI web site lately. Their 600 series cameras are quite different than 500 series cameras. The download speed is much faster and the cooling is up to 45C below ambient at 85% cooling power. Their download speed is now less than 7 seconds in high quality mode and 0.7 second in high speed mode. I really don't care for 7 second download speed during imaging session but 0.7 second for focusing will come in handy.

http://www.qsimaging...0-overview.html

Peter



I was mixing the 500 series "joke of a camera" (joke's on you though!) with their latest offerings that have now put them in essentially the same speed range as you could have bought since 2008 from FLI

I am sorry but to me it looks like they are perpetually playing catch-up but without any solution for a large sensor nor any comprehension of image lag caused by RBI and the importance of mitigation for KAF series sensors...


help me understand where I got it wrong :jump:

#21 Konihlav

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Posted 01 August 2012 - 10:26 AM

For me the KAI4022 was ideal for my 18" Cassegrain:

1) using it at 3366mm I get an image scale of 0.45"/pixel and that goes well with my seeing in the 1.2-1.5" range.

OK, using 18" scope at such a long(er) focal length goes beyond what my brain capacity can cover (never thought of ever using such a scope in my short life) :)

2) using the electronic shutter I can take very short flats... 50msec is easy,so sky flats are no problem: even with a luminance filter.

good point. A minute ago when I was capturing flats for my new Atik 460EXM in order to measure readout noise (ended with 5.017e-) I was using 0.016 seconds for a flat field.
I love these tiny Sony chips, all set of flats is done within few minutes. On the other side the large 11K camera I have (and "love") has also download around 18 seconds (in bin 1x1) and that's eternity. But for the purpose and being cheapest (smallest, lightest, low RN, high build quality, great electronics...) out of the big brands... makes me to freely (without feeling bad) recommend Moravian cameras to EU astroimagers :)

can you do that with a QSI583?

I do not care about QSI, SX, QHY... just my opinion. Now I have all I dreamed about (one very large chip and one small, but top QE and ultra low noise).

On the QE, it isn't as bad as you make it sound... The pixels are the same pixels used in the KAI16000 and all other sensors with the 7.4 micron interline. A reduced QE simply means you take more exposures. However I can tell you that the number of additional exposures will be a function of the read noise and exposure parameters.

so you can be in a situation where you can get a better S/N in less time using a camera with a lower read noise despite a lower QE than one with a higher QE and higher read noise

yes, it is that bad as I describe it. That made me wonder why you have KAI-4022 :-) it's very "blind" to Ha and SII photons.

the later is true - lower noise camera even with lower QE "wins" almost all the time.

Richard, I had a hard time to persuade people to focus on low readout noise cameras (nobody understands it and not many wants to understand it), see this thread:
http://www.cloudynig...98/Main/5260581

so even if you've been there and done that, experience can't be transferred or shared (can be shared but be prepared noone want's to adopt it).

:)

life is hard!

Peter - may you now have a hard time to decide I guess :)

no offence - clear skies to all you guys!

#22 Richard Crisp

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Posted 01 August 2012 - 10:32 AM

Well Richard,

One cake decorator is Nik Szymanek (ccdland.net)
With all due respect to the links you posted I feel his images with QSI are more convincing.


Yeah I think Nik was making excuses for the dog-slow download speed of the QSI583... as something he could live with...

Come on: do you not value your credibility? that is a ridiculous statement....

Are any of these gentlemen electrical engineers?

do any of them have a multi-decade background in microelectronic development with tens of issued patents?

do any of them have peer-reviewed technical papers in publication from professional journals in the field of electronic imaging or papers presented in such conferences sponsored by such professional organizations?

It is one thing to be a photoshop jockey and it is quite another to have solid academic and professional credentials in the field and to be able to quanitify critical performance parameters in a reproducible manner and to put into perspective the system level implication of the various parameters.

That's what I have not seen in ANY of these reviews, nor have I see such qualifications from ANY of the reviewers..... Did I miss something?

instead I read totally irrelevant things like "it is a nice blue color and the fit and feel is really good" by some fellow that may be a retired pipefitter that cannot solve the noise equation for a CCD or even what the terms mean.

that's about as useful and relevant to me as knowing who Lindsay Lohan ran her car into last night quite frankly....

Unfortunately most of the buying public is influenced by this irrelevant drivel brought to you by those that receive for free the product that they were glowing about yet nowhere was that disclosed as a caveat in their review now was it? :D

#23 Konihlav

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Posted 01 August 2012 - 10:40 AM

just an example, why I would not recommend KAI-4022 for narrow band, especially for Ha and SII it's a PITA.

case A, camera with 5e- RN and 55% QE in SII, using only 10min subs to get some SNR ratio on a dark sky (counting skyflux 4e- i.e. dark sky and using narrowband filters) would need 16 minutes of total exposition time (total integration, which in 10min subs is equal taking 2 light frames).

case B, camera with 9e- RN and 28% of QE in SII, using only 10min subs to get some (same as in previous case) SNR ratio on a dark sky (counting skyflux 4e- i.e. dark sky and using narrowband filters) would need 117 minutes of total exposition time (total integration, which in 10min subs is equal taking 12 light frames). See the difference?

if, you take, with camera B, much longer sub (as we all know why) then you end with "only" needing 48 minutes of total integration time (i.e. two 30min subs). I was counting with 30min sub.

48 is still 3 times more than 16 so with KAI-4022 you need 3x more time on given object than with ICX694!

of course, the situation with broad band LRGB and city sky is completely different - here it's the "same" you do not benefit from low RN camera. You only benefit from high QE! which is something ICX694 does have.

a side comment - I will repeat myself - If someone wants to spend $6000 for KAF-3200 then it's an "idiot" when he could have same performance (or even much better performance) for half price!

people's needs differ.

#24 Peter in Reno

Peter in Reno

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Posted 01 August 2012 - 10:43 AM

Richard,

You may be smart but there's no need to be an *BLEEP*. You can contibute and help others to this forum by being a little more diplomatic. If you want to continue to bash, please do that at another forum.

I do not want this thread locked if there's going to be continuation of bashing.

Peter

#25 Peter in Reno

Peter in Reno

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Posted 01 August 2012 - 10:49 AM

Peter - may you now have a hard time to decide I guess :)


So far I have not yet decided. I want my next purchase to be the right one.

Peter






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