You are correct here, but the manufacturer normally provides this and much more data to you.
Theo
True Theo but you only have to read a small number of threads on this forum to work out most people present hypothetical arguments. Greg and Mike have put there money where their mouths are and provided the evidence. This appeals to the scientist in me .
I have spent a little time working with complex analytical instruments of which the cost makes these camera's look like kids toys. Even these have problems with noise. But the noise always has many contributers and is rarely the result of a single weakness. This will be the same with the camera's and it is well displayed by the images Greg and Mike have provided comparing two camera's with the same chip. The processor, firmware and electronics must play a part. What I would like to see is how well Qiu has delt with this problem on the QHY11.
It seems almost identical to Mike's Proline 11002 dark. The FLI electronics/firmware account for a large difference.
My Apogee camera is also very noise free although not quite as noise free as the FLI.
Also I can get -35C all year round. In winter I imagine the camera would go to -45 to -50C possibly lower. It seems to do -60C below ambient.
As you can see there is more to camera manufacturer choice than simply the same chip.
Greg.
Heres a 10 minute dark from the upcomming QHY-11, its a raw FIT file so be carefull its big http://www.qhyccd.com/QHY11/10min%20dark.fit and temp was only -20deg .
I'm not defending SBIG or anyone else here, just saying cooling counts the most. Here is the 8300 10 minute dark as well http://qhyccd.com/QHY9/dark%20frame%20600sec%202.rar . The temperature was 0 deg. This ccd is very low noise to start with, so out of the box, any 8300 camera will aready be a mile ahead. I expect SBIG to produce similar if not better darks as well now.
True Theo but you only have to read a small number of threads on this forum to work out most people present hypothetical arguments. Greg and Mike have put there money where their mouths are and provided the evidence. This appeals to the scientist in me .
I have spent a little time working with complex analytical instruments of which the cost makes these camera's look like kids toys. Even these have problems with noise. But the noise always has many contributers and is rarely the result of a single weakness. This will be the same with the camera's and it is well displayed by the images Greg and Mike have provided comparing two camera's with the same chip. The processor, firmware and electronics must play a part. What I would like to see is how well Qiu has delt with this problem on the QHY11.
Ciao Mark
Mark, this has absolutely nothing to do with defending ANY camera.
There is no question that you get what you pay for.
Secondly, Mike and Greg can make an award winning image using a Kodak Brownie camera.
The discussion here (And i hope) is purely noise and the CCD, and the effects of cooling and the such.
Its not about the best camera out there.
Im just waiting for Peter Ward to post some of the SBIG darks, and im dead sure it will be just as good as the ones posted here by Greg and myself.
Oh yeah, if at any time you ever want to plonk ya camera behind my new scope Mike, im available baby !!.
Heres a 10 minute dark from the upcomming QHY-11, its a raw FIT file so be carefull its big http://www.qhyccd.com/QHY11/10min%20dark.fit and temp was only -20deg .
I'm not defending SBIG or anyone else here, just saying cooling counts the most. Here is the 8300 10 minute dark as well http://qhyccd.com/QHY9/dark%20frame%20600sec%202.rar . The temperature was 0 deg. This ccd is very low noise to start with, so out of the box, any 8300 camera will aready be a mile ahead.
Theo
The 11 looks very nice indeed Theo. I will keep my eye out for this one.
The 11 looks very nice indeed Theo. I will keep my eye out for this one.
Ciao Mark
Mark, keep your eye out for ALL brands.
I have seen some preliminary images from many cameras, and specs on many more.
You guys are in for a BIG choosing spree soon.
You said it best yourself, theres a reason it costs so much. The same reason why i spent so much money on my scope and mount.
Basically if you can afford it, then you can "afford" it.
In a few months, users will have a barage of different models from ALL the manufacturers with prices that will be affordable.
Me, my camera will have the 9000 sensor in it as my choice. Once the price is reasonable, and i wouldnt care if Target brought it out. If the specs are good and the camera works as per that, then its mine.
Now I can see why you thought the FLI's were so much better than the STL11K, Man what a difference and I wasn't even at the slower lower noise download speed, I might have to try using the slower download speed?
Yes the PL11002 dark looks very similar to the 8300 dark, maybe even the 11002 is slightly better?...something I didn't expect. What download speed are you using Greg?
I came from Starlightxpress Sony chips that have virtually no hot pixels and very low noise, they simply do not need darks, so I thought my PL11002 was noisy actually, now I feel better, the STL chip looks like a snow storm
Mike
Hi Mike,
I am not sure how you set the faster download speed of the FLI so I just use it with CCDsoft and there is no switch or anything. It takes about 5 seconds with 1x1 binning so I guess that is the slow download.
You need to check that it still downloads at 16 bit resolution at the 1 sec xfer speed.
Manufacturers place either a dual 16/12 bit ADC or 2 ADC chips where 1 is for 12 bit (Fast download) and the other is 16bit (For normal download).
This is a technique used to increase speed.
These sort of setup's will be used more and more in the future.
Addition: Brute force Speed is also used too, and as said, noise becomes the weakest link and suffers here.
For some images ive seen using high speed, you really need to look to see that noise too.
Theo
Everything is 16 bit in the FLI download. In high speed (12MPPS), there is more reset and clock noise than at 1MPPS. But, with the KAI11K it has much higher dark current during readout so the slower 1MMPS only shows negligible decrease in noise, probably a couple of electrons. This is why I stay with the lightning fast 12MPPS download speed
Greg, when the manufacturer specifies the readout noise, they do it at the slowest speed, and that speed is listed as the noise@speed.
So lets take the FLI Proline model PL09000 (My dream), its able to download at 8MHz Max, but FLI specifies the readout noise as : Typical System Noise: 9 e- RMS @ 1 MHz
Readout noise will be as specified when the speed is at 1MHz, which of course slows the download down, but makes dem pectures perdee.
In fact, all the front illuminated proline series that i can see on their web are 1MHz for the readout noise.
Goes to show you, when you find something thats works, and works well, stick to it.
Why would you prefer the 09000 chipped camera over the 16803?
I thought the 16803 was better for longer focal length scopes?
Or do I have that the wrong way around - the larger pixels being better for
long focal length scopes?
The 09000 chip is very prone to RBI (residual bulk image - ghost images of earlier bright exposures). Whilst both FLI and Apogee have an
RBI fix which consists of preflushing the chip prior to exposure with an LED
it does increase noise.
The 09000 has slightly better QE and well depth both of which the 16803 has in abundance so the improvement I imagine would not be that noticeable.
Apart from Adam Blocks PR images for Apogee I have yet to see an impressive 09000 image. It doesn't seem that popular a choice. I have heard of a few complaining about RBI making the camera useless without the RBI feature turned on.
By the way I am hanging out for some images from you out of your super rig! How's that coming along?
Well finally this camera is on its way from Bintel. It took quite a lot longer than originally promised by the manufacturer. In fact it was 7 weeks longer. I think next week is week 14 from order. Bintel were very helpful in the process and Michael really was very gracious when I started getting hot under the collar about delivery. Thanks Michael.
Now, I have Maxim but am thinking I should really get CCD soft for camera control and guiding. Any thoughts.
I should have the camera sometime on Monday as it is being delivered by TNT and it was sent today. That might be wrong though.
How long should I run the subs in each colour. I am thinking that 10 minute subs should be fine on Galaxies and most nebula. Am I right in thinking this? Or do I need to go lower. What sort of guidelines in settings should I apply? I have no idea on this.
Is there a bias I need to take into account for the blue channel on the KAF8300 chip? I know that many of the older chips needed longer time in the blue channel as these chips had trouble in collecting blue photons.
So it looks like it is a single image either in one night or over a period of nights. Would love some help from the guys on this.
IMHO there is a lot of BS surrounding this thread.
This year's (and many other) David Malin Award deep sky winners used a SBIG.
As do Gendler, Cronman, Block et. al. Just take a look at any gallery section of S&T, Astronomy, AS&T.
You can ruminate as much as you like, but the SBIG system works extremely well.... name any other company that offers integrated AO that can be used ahead (via a MOAG) of the filter wheel. Duh...none?
Starlight Xpress via their SX-AO unit and a lodestar can be used infront of the filter wheel? Granted the camera does not come with the guider, and the whole setup does not look quite as well engineered, but they do have what you're talking about...
Don't get me wrong, the SBIG camera's I've owned have both blown me away.. and I think my next camera will likely be an SBIG again... I just like the software control and self guide...
Well finally this camera is on its way from Bintel. It took quite a lot longer than originally promised by the manufacturer. In fact it was 7 weeks longer. I think next week is week 14 from order. Bintel were very helpful in the process and Michael really was very gracious when I started getting hot under the collar about delivery. Thanks Michael.
Now, I have Maxim but am thinking I should really get CCD soft for camera control and guiding. Any thoughts.
I should have the camera sometime on Monday as it is being delivered by TNT and it was sent today. That might be wrong though.
How long should I run the subs in each colour. I am thinking that 10 minute subs should be fine on Galaxies and most nebula. Am I right in thinking this? Or do I need to go lower. What sort of guidelines in settings should I apply? I have no idea on this.
Is there a bias I need to take into account for the blue channel on the KAF8300 chip? I know that many of the older chips needed longer time in the blue channel as these chips had trouble in collecting blue photons.
So it looks like it is a single image either in one night or over a period of nights. Would love some help from the guys on this.
Sorry Paul, I wish I had the experience to answer your questions, I was following your thread till all the arguments of who's is bigger than who's. Hopefully your thread gets back on track.
Starlight Xpress via their SX-AO unit and a lodestar can be used infront of the filter wheel?
Yes and no. SX is not an integrated solution. Only SBIG offer a choice in selecting an internal (self guide) or external (RGH) chip controlled by the same camera head that can feed into their AO...and if you happen to own an AO7 you can guide at around 30Hhz...something SX can't do
Don't get me wrong, FLI, SX etc. and...to a lesser extent Apogee offer good products, but IMHO they have less sophisticated guiding accessories and software.
Peter, one day I will be buying an SBIG and it will be from you if you remain civil. Be assured of that. It will be something like the STL11000 or whatever the current version is at the time. However for now I cannot afford much more than this. The price of the SBIG units was way more than I paid for the QSI. I got this at a good price, could you now get back on topic here and if you have more to contribute; perhaps answer my questions. I would like some questions answered. Thank you.
First thing to test, is your subs length. I cant use more than 5 minutes maximum because i get blooming on the brighter stars. But then again i have a 20" mirror pushing the photons. Just do a test on a moderatly bright (3rd or 4th mag star) by taking a 5 and 10 minute sub and check for blooming.
The 8300 does have lower blue and red response, green is the highest response, so you may want to increase your blue/red subs by 50 %.
I have attached the QE of the 8300 for you to have a peek at.
.
and I wasn't even at the slower lower noise download speed, I might have to try using the slower download speed?
.
