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ST-8300M vs STF-8300M

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#1 Grafff

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Posted 08 March 2012 - 06:57 AM

It was recently announced a new camera from SBIG: STF-8300M. There is improved electronics, but ... + $ 700. What is the best choice:

SBIG ST-8300M -- $1795
SBIG STF-8300M -- $2495

#2 DugDog

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Posted 08 March 2012 - 08:19 AM

The new Model STF-8300 is SBIG's second-generation camera using the popular KAF-8300 CCD. The STF-8300 has new, faster, electronics with 10-megapixel/second digitization rate and a full frame image buffer. The high resolution image downloads in less than one second. The camera uses SBIG's traditional even-illumination, photometric shutter design, and adds a user rechargeable desiccant plug.


For $700 you get your image download faster?

The Parsec already has "internal full-frame 32 megabyte memory buffer" but it downloads in 10 seconds.

$700 can buy a lot of equipment, maybe people will feel better about the extra "F" in the model name, that could be worth $700?

If it was me, I'd keep the $700, and I can wait a few extra seconds for the download. :foreheadslap:

#3 Grafff

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Posted 08 March 2012 - 08:45 AM

It seems that there is a difference not only in the time of downloading, but also in the value of Dark Current:
ST-8300M: ~0.02e-/pixel/sec at -15C http://www.sbig.com/ST-8300M.html
SBIG STF-8300M: 0.002e-/p/s at -10C http://www.sbig.com/...Monochrome.html

#4 jrcrilly

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Posted 08 March 2012 - 08:58 AM

Having had to recharge a few over the years, the user-serviceable desiccant would be worth something to me. I'd hate to have to ship the thing in every time.

#5 dawziecat

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Posted 08 March 2012 - 09:30 AM

Having had to recharge a few over the years, the user-serviceable desiccant would be worth something to me. I'd hate to have to ship the thing in every time.


Ship it in for a desiccant replacement? :bigshock:
Say it ain't so!

Page 34 of the ST8300M manual says "it's easy to replace" and gives instructions.

#6 Grafff

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Posted 08 March 2012 - 09:33 AM

Page 34 of the ST8300M manual says "it's easy to replace" and gives instructions.


Don't looking for an easy way when it's possible to find a hard way! :roflmao:

#7 jrcrilly

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Posted 08 March 2012 - 09:48 AM

Page 34 of the ST8300M manual says "it's easy to replace" and gives instructions.


Don't looking for an easy way when it's possible to find a hard way! :roflmao:


Cool! Not nearly as convenient as the rechargeable plug on the STF (and on all of the SBIG cameras I've owned) but far better than sending it in. That reduces the relative value of the new feature. Still worth something but it makes the decision a little harder.

#8 jmasin

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Posted 08 March 2012 - 09:48 AM

It seems that there is a difference not only in the time of downloading, but also in the value of Dark Current:
ST-8300M: ~0.02e-/pixel/sec at -15C http://www.sbig.com/ST-8300M.html
SBIG STF-8300M: 0.002e-/p/s at -10C http://www.sbig.com/...Monochrome.html


Not arguing, but hard to believe given they are the same sensor... unless there's something being done off-chip...

#9 Grafff

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Posted 08 March 2012 - 10:01 AM

Not arguing, but hard to believe given they are the same sensor... unless there's something being done off-chip...

This improvement (with the same sensor) of the value of Dark Current seems to be very strange, as for me. But... this is official information from the official web-site.

#10 buckeyestargazer

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Posted 08 March 2012 - 12:48 PM

Please take what I say with a grain of salt because I have no experience with either of these cameras. :question:

Unfortunately for me cost is a very big factor. If it were up to me I would opt for the ST8300M because I don't see much new that would justify the $700 price difference. However, if slow download speeds etc would drive you nuts and you can afford it, go for the STF. Personally I might be tempted to wait for some of the new Sony chip-based cameras before buying an STF.

#11 Grafff

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Posted 10 March 2012 - 07:39 AM

It would be interesting to read an owner's review of the camera.

#12 Alph

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Posted 10 March 2012 - 12:48 PM

It seems that there is a difference not only in the time of downloading, but also in the value of Dark Current:
ST-8300M: ~0.02e-/pixel/sec at -15C http://www.sbig.com/ST-8300M.html
SBIG STF-8300M: 0.002e-/p/s at -10C http://www.sbig.com/...Monochrome.html

That's a typo or false information which is not uncommon on the SBIG website. Be careful not to bring to their attention on their yahoo group otherwise they will terminate your membership

#13 MattThomas

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Posted 10 March 2012 - 02:20 PM

Alph,

Your statement is not at all true. I'm sorry that you feel we will take such action for someone asking a simple question.

The dark current measurements for the STF-8300 were actual results from pre-production cameras - and were measured with a more accuracy than normally measured in production.

I don't expect the actual dark current data to be any different in the ST/STF cameras. The ST-8300 is likely similar, but not previously measured with similar accuracy.

#14 vdb

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Posted 11 March 2012 - 04:50 AM

there is an error in your measurement ...
or there is a new enhanced version of the chip ...
Apogee and also many other vendors state much higher dark current ...
The value sbig brings is better then Sony exview chip, and that my friends seems very unlikely ...
Apogee:
0.02 e-/pixel/sec (-30° C; D02 housing); <0.006 eps for High Cooling D09 housing.

#15 MattThomas

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Posted 11 March 2012 - 10:43 AM

Apogee:
0.02 e-/pixel/sec (-30° C; D02 housing); <0.006 eps for High Cooling D09 housing.


And you take this as the gold standard? Using our less accurate measurement (with only hundredths resolution) we see 0.02 e-/pix/sec average at -10C. (Many ST-8300 cameras measured 0.01 e-/pix/sec or 0.00 e-/pix/sec @ -10C which lead to the more accurate measurements for the STF-8300 pre-production cameras.)

#16 Alph

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Posted 11 March 2012 - 11:34 AM

And you take this as the gold standard?


What about the full well depth of the KAF-3200? Is anyone else wrong again? Your website reports 77Ke while others state 55Ke.

#17 vdb

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Posted 11 March 2012 - 12:43 PM

I'm not taking this as the gold standard it was just one example I could find, here another one from QSI:
Pixel Dark Current <0.02 electron per second at -10°C
But hey if sbig can make a camera that has 10 times less dark current I'll sell my QSI 683 in a blink of an eye ...

#18 MattThomas

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Posted 11 March 2012 - 02:55 PM

And you take this as the gold standard?


What about the full well depth of the KAF-3200? Is anyone else wrong again? Your website reports 77Ke while others state 55Ke.


Well, I don't doubt that you may find some errors on our web site, just as you would on any other.

But in this case, we quote the typical full well achievable on our cameras. It would seem "everyone else" (per your term) is using Kodak's nominal full well specification from the 3200 datasheet. This doesn't mean that their 3200 based cameras don't achieve the same full well as ours.

And just to see, I powered up my personal ST-10. The gain is 1.32e-/ADU, and full well is around 60000 ADU:

60000 * 1.32 = ~79000

#19 MattThomas

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Posted 11 March 2012 - 03:07 PM

I'm not taking this as the gold standard it was just one example I could find, here another one from QSI:
Pixel Dark Current <0.02 electron per second at -10°C
But hey if sbig can make a camera that has 10 times less dark current I'll sell my QSI 683 in a blink of an eye ...


There is nothing that says the QSI is better or worse than SBIG in this spec. They could be the same based on the way the specs are written. We are both better than 0.02e-/pix/sec at -10*C.

But for reference, you do realize that the QSI spec is 10x better than the Apogee spec? With a 5.8*C doubling (halving) temp for dark current on the 8300, the difference in dark current from -10*C to -30*C is a factor of 10.9 difference. If Apogee is claiming 0.02e-/pix/sec at -30*C and QSI is claiming <0.02e-/pix/sec at -10*C, that would be <0.0018e-/pix/sec at -30*C for QSI.

As for selling your QSI 683, have you measured your dark current? What do you get on your camera?

#20 vdb

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Posted 11 March 2012 - 03:48 PM

Never measured it on any of my camera's but maybe I should, I did realize that QSI is also more optimistic then Apogee ... but still much more dark current then the sbig's ...

#21 Grafff

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Posted 11 March 2012 - 04:08 PM

Dear Matt!

Describe, please, all advantages of STF-8300M relatively to ST-8300M. Thanks!

P.S. As for me, SBIG is simply the best: excellent quality, fair price, good soft; IMHO.

#22 jrcrilly

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Posted 11 March 2012 - 07:04 PM

Dear Matt!

Describe, please, all advantages of STF-8300M relatively to ST-8300M. Thanks!


Let's not push Matt into a posting violation. He knows that he can answer specific questions here in CCD but broad product descriptions are limited to the vendor Announcements forum.

#23 MattThomas

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Posted 11 March 2012 - 10:17 PM

Describe, please, all advantages of STF-8300M relatively to ST-8300M. Thanks!

P.S. As for me, SBIG is simply the best: excellent quality, fair price, good soft; IMHO.


Answered privately. Thanks Grafff.

#24 Alph

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Posted 11 March 2012 - 11:51 PM

But in this case, we quote the typical full well achievable on our cameras. It would seem "everyone else" (per your term) is using Kodak's nominal full well specification from the 3200 datasheet.


SBIG must have been getting special treatment from Kodak. The typical full well depth in your ST-10XME exceeds the nominal value by %40 = (77,000 - 55,000)/55,00; and the minimum value by %54 = (77,000 - 50,000)/50,000

And just to see, I powered up my personal ST-10. The gain is 1.32e-/ADU, and full well is around 60000 ADU:

60000 * 1.32 = ~79000


Your math is wrong. The unit of Gain is ADU/electron which means that the pixels in your ST10XME (gain = 1.32) saturate at 49,648[e] = 65,535[ADU]/1.32[ADU/electron] just a tad below the minimum value specified by Kodak. So even if the KAF-3200 CCD you sell had the well depth of 77Ke then your ST-10XME camera does not take advantage of it.

I am afraid that the typical full well achievable in your cameras is 49,648 electrons not 77,000

#25 MattThomas

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Posted 12 March 2012 - 12:49 AM

Your math is wrong. The unit of Gain is ADU/electron


Alph,

My math is correct. SBIG always quotes gain in e-/ADU.

For your reference:
http://www.sbig.com/ST-10XME-C2.html






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