Asi1600 or 8300ccd

[Ken82]

Hi all,

so it’s time I made the change from modified canon 6d to a cooled Astro camera. Question is what should I get ?? I appreciate I’ll need to cut down on field of view moving away from a 36mm sensor so I’ve decided on either the asi1600 or kaf8300 (possibly atic 383l). 

Ive been reading a bit and I’m slightly concerned by the amp glow and reflections on the asi. Has this been resolved ? Can you remove it with flats/darks ? 

I’m also imaging from a reasonably light polluted sky so would I gain no benefit from the longer exposures of the 8300? 

Im using a takahashi  fsq85 for widefield and esprit 120 for smaller galaxies etc etc so pixel size fits either really. 

What are people’s opinion on these two and what should I purchase ?

thanks ken 

 

[wxsatuser]

I'm biased so it would be the Atik 383L. ?
It does'nt miss a beat and works fine with narrow band from LP sites with a nice fov.

Cannot comment on the asi but someone will give you an alternative opinion to mine about it.

[Ken82]

Wxsatuser would it be ok taking colour photos at only 3min exposures ? 

[RayD]

As with all these questions you will never get a definitive answer here, just a whole raft of differing opinions.

My preference is for CCD, but only because I don't want the large number of files produced by the CMOS as you need to then consider storage and processing of the images.

Both cameras will work fine, with the CMOS possibly being better for you if you do have particularly light polluted skies, but many people have managed for years to image in light polluted skies with CCD, so.........

It could also come down to cost, with an older version ASI probably being cheaper than the Atik, but you then may be introducing amp glow as that was only addressed in the later iterations.

As you can see, no answer, just differences and benefits of each. 

[Davey-T]

Ignoring personal preferences, the ASI1600 advantage is it's ability to capture low noise short images a good thing if your guiding is crap, it's disadvantage is clogging up your HD with huge files, bearing in mind a 30 second exposure has the same file size as a 30 minute one.

8300 CCD versions may be "old technology" but it works, there's  a plentiful supply of second hand ones and if you're so minded you can do one 240 minute exposure as opposed to 14000 odd CMOS ones 

Dave

[wxsatuser]

11 minutes ago, Ken82 said:

Wxsatuser would it be ok taking colour photos at only 3min exposures ? 

Cannot help on that as I only do Ha and that's easy to do very long exposures, depending on target.

[wxsatuser]

1 minute ago, Davey-T said:

Ignoring personal preferences, the ASI1600 advantage is it's ability to capture low noise short images a good thing if your guiding is crap, it's disadvantage is clogging up your HD with huge files, bearing in mind a 30 second exposure has the same file size as a 30 minute one.

8300 CCD versions may be "old technology" but it works, there's  a plentiful supply of second hand ones and if you're so minded you can do one 240 minute exposure as opposed to 14000 odd CMOS ones 

Dave

I bought both mine for around £900 which is a bargain.

[steppenwolf]

If you can run to the KAF 8300 sensor, I'd go for that but I too am biased as I have a QSI CCD camera with this sensor.  The 1600 sensor can also produce great results but CMOS has only recently come of age for astro cameras and there is still some ironing out to be done to get the best from them especially with regard to amp glow and calibration whereas the much older 8300 technology is well understood and pretty bomb-proof.

[Ken82]

How would colour imaging work with the 8300 as I currently use a light pollution filter? Would I have to use my LP filter in front of the RGB filters, how does that work ? 

[LightBucket]

The 8300 CCD every time...

[vlaiv]

Depends on your imaging preferences really. I weighted two against each other and decided to go for ASI1600 based on my scopes and preferences.

ASI1600 has few drawbacks compared to Kaf8300:

- Presence of FPN (telegraph noise). This is something that you can deal with in certain ways - probably best is to dither your subs

- Some people have issues with calibration (amp glow, problems with flats, etc ...). Can't comment on that because my calibration works every time and I had no any of the mentioned problems although I have older model - V2 (non pro)

- Very large data sizes to work with. This is very true, but it is manageable - I tend to shoot tons of calibration frames (like 256 of each) and while it does take up tens of gigs of storage space, I'm used to it and it really does not pose such a problem

- 12bit ADC - this dictates style of imaging (you need more subs to get bit range dynamic equivalent to 16bit) - more shorter subs.

On the other hand, here are benefits:

- Lower read noise

- Lighter camera (if that is an issue for you because of focusers on scopes or whatever)

- Smaller pixel size - you can get finer resolution for wide field, or you can bin to get larger pixels (still less read noise than Kaf8300) on longer scopes - to me this means more flexibility

- Faster download time (this is good if you go for short subs, on ASI1600 frame download is around 1s - so less time wasted)

[Jkulin]

I have owned two 8300 CCD cameras, the first an Atik 383+ which was very good, but I wanted to use an OAG and the backfocus limitations didn't work out and I wanted to shoot at -20 rather than struggle at -15, so I waited patiently for the new Moravian G2-8300 MKII, I noticed an exceptional difference between the two, the Moravian wasn't anywhere near as noisy and it consistently ran at -20, The back focus issue was resolved but I moved away from using the Moravian OAG as it really was poorly designed and went back to my Celestron OAG on the RC and used guide scopes on my Esprits.

I'd loved to have waited for the new QSI683, but their filter wheels still don't hold seven 2" filters and supply is still very unsure, for the price I really don't think I could have got better than the Moravian, I'm very pleased with it.

HTH

[Adam J]

Am very happy with my ASI1600mm pro the amp glow is a none issue don't even know why it's coming up just take darks and it's gone. The microlense reflections are the only real problem with the sensor. I can afford to use astrodon filters with the ASI can't afford the larger ones required for the 383L+ 

[swag72]

I really rate the 8300 sensor and I use it with the FSQ85 as well as 1.25" filters. I have a QSI683 and also a Moravian G2-8300 (Both have an internal filter wheel). No darks are needed for these camera's, they run all year round at -15 degrees here in Spain. I use bias and flats and they really do calibrate out fine. If you do some internet research then there are folks who say that the 8300 sensor is long in the tooth, but I am very pleased with it. I always use long NB exposures of 30 mins, for luminance I use either 10 or 20 minutes depending on target and RGB I use 5 mins. I use a LP filter as the luminance filter and don't have any type of filter in place for the RGB. People think that I have dark skies here, but I don't .

[MartinB]

I have had a QSI 532 for many years and always been very pleased with it.  Recently I decided to get a second mono camera for wider field imaging using shorter focal lengths than are ideal for the 532.  In the end I went for the ASI 1600 pro and, so far, have been mighty impressed.  The build quality is very good and it produces very clean images.  I think the extra expense of CCD cameras is becoming hard to justify.

I am still very new to the camera and still experimenting but here is an image of the heart and soul combining 30 x 5min Ha subs taken using a 200mm lens at F2.8.  I think any CCD user who spent a bit of time with this camera would come away as impressed as me.

 

[Rob63]

Very good information on the ASI1600MM at Jon Rista's site

https://jonrista.com/the-astrophotographers-guide/the-zwo-asi1600-guide/

I have had mine for a couple of months (latest pro version) and am very happy with it.
Amp glow is not an issue unless you start going over 5min exposures - and if you want to do longer exposures then CMOS is not really for you.

[JukkaP]

Sorry for mixing. But have seen great images whit asi 183 and both of those scopes. It is little smaller size chip. But I would go for the newest technology out there. The 183 is best ccd type of cmos out there.

 

As for those 2. Plenty of topics around there. Many have changes from kaf8300 to asi 1600. But for me the lack of AR coating in no go for the 1600. I would take the 8300 over the 1600.  

[Andyb90]

One thing I like about the 1600 is the variable gain. This gives you flexibility. You can react to sky conditions as they arise. For example if skies are completely clear with no sign of cloud you can reduce the gain and go for longer exposures (depending on lp, tracking accuracy etc). However if you get intermittent cloud you can raise the gain and get some short exposures in between the clouds. I've done 2 minute Ha subs with high gain to get some data when clouds have drifted in and out.

Edit: Just thinking shorter exposures give you additional flexibility in that you can select the best ones. You can easily cut a few bad subs without loosing too much data overall. I guess with longer subs like 20 mins + any loss will hurt.

Whilst you will have more data to process with shorter exposures it should'nt be too much of an issue with a half decent processing pc and storage is very cheap these days.

Andy.

[Laurin Dave]

Hi Ken,

I have ASI1600mm latest model, amp glow not an issue with matched darks. Mine have been absolutely fine up to 10minutes, I've found that I need to take the camera off the scope, put the cap on and point it into a table to get good darks. (There must be light leaks in my system somewhere and I do darks during the day). Reflections, well mine look like this on Alcyone, halos and microlensing caused by the lack of AR coating on the sensor. Starts to become obtrusive around mag 5-6 on my system. To get around this I use a full frame DSLR on the bright stuff.. M42, Pleiades..  etc  I've also used it for lucky imaging on the planets and the sun so its pretty flexible.  I really like it and would recommend it but for ultimate deep sky image quality, from what I've seen CCD wins.  (I'm getting one)

Dave

 

 

 

 

 

 

[MartinB]

On 24/11/2018 at 12:30, Ken82 said:

I’m also imaging from a reasonably light polluted sky so would I gain no benefit from the longer exposures of the 8300? 

There is no great benefit from longer exposures once shot noise and/ or sky glow is sufficient to make the read noise insignificant.  The lower the read noise the shorter the sub length required.  CCDs generally have higher read noise than CMOS so need longer exposures.  This is a disadvantage rather than an advantage!  Long exposures ultimately can lead to a loss of signal simply because of subs having to be ditched owing to the odd stray cloud and the like.  There is nothing more frustrating than watching a band  of cloud move in on a pristine sky when you are 2 minutes from the end of a 30min sub!  

When using narrow band filters sky glow is massively reduced so you need longer exposures before the read noise becomes insignificant.  Even at 30mins with a 7nm ha filter read noise still hasn't been eliminated with my QSI 532 but I don't go longer than this.  Getting decent statistical rejection when combining subs really requires a minimum of 10 subs.  For an HST image this requires a minimum of 15 hours of exposure time using my CCD, double that if I was using 1 hour subs.  5 minutes with my ASI 1600 seems roughly comparable with 30mins with my KAF in terms of optimal sub exposure time.   

 

[Ken82]

Thanks for all the input here guys very informative! A friend of mine has suggested matching the pixel size to my colour camera so I can combine narrowband and colour. I think this is interesting so I may look to get both a mono and colour camera with the same pixel size for ease of use. Only think is zwo don’t produce the asi1600 colour anymore 

[MartinB]

You don't need the same pixel size to match mono and colour.  You just need software to scale one image to match the other.  It isn't hard to add a colour DSLR image to a mono image produced by an astrocamera. with appropriate software

[tooth_dr]

1 hour ago, MartinB said:

You don't need the same pixel size to match mono and colour.  You just need software to scale one image to match the other.  It isn't hard to add a colour DSLR image to a mono image produced by an astrocamera. with appropriate software

I've done it a few times, APP registers and integrated the data really easily from the colour camera, to your reference mono image

[noah4x4]

7 hours ago, Ken82 said:

Thanks for all the input here guys very informative! A friend of mine has suggested matching the pixel size to my colour camera so I can combine narrowband and colour. I think this is interesting so I may look to get both a mono and colour camera with the same pixel size for ease of use. Only think is zwo don’t produce the asi1600 colour anymore 

The Atik Horizon is Atik's equivalent (e.g. same sensor etc) of the ASI1600 and still available (albeit I believe that the sensors are in short supply, hence possibly why the ZWO is no longer available).  I have the Horizon OSC version. It offers 16 megapixels and I think it is fantastic especially if images are fed to a 4K UHD monitor via a suitable graphics engine, but I don't claim any great expertise merely satisfied  user experience. Larger pixels equals higher sensitivity is usually good advice if buying a CCD for regular AP.  However, because the Horizon OSC is CMOS it handles colour binning via software not hardware. Combining pixels improves sensitivity,  but the way it does it via software doesn't appear to sacrifice any of its 4K resolution. That makes it a great pairing on Hyperstar where deeper <zoom> is desirable due to the (Hyperstar)  increase in FOV but lower magnification. Atik has also overcome the Ampglow issues. I love this OSC camera with Hyperstar as I require no wedge, no polar alignment, no guiding as my exposures are between 2 seconds and 30 seconds at Hyperstar's f/1.9.  Creating images 28x faster is cloud beating. Atik Infinity EAA software is also awesome as it is camera dedicated, has simple presets, and has merely a 22 page manual. So easy!

However, if seeking a mono camera I suspect that the Atik 383L will be superior despite it being only 8 megapixel (but remember larger pixels on CCD tend to be better - here with large sensor). It is around £1,794 compared to the Horizon mono at £1,607 and Horizon OSC at merely £1,257.  I gather the strange Horizon pricing has much to do with sensor supply. It also interesting to see Atik describe the Horizon as "entry level" and the 383i as "Large Format".  

[DaveS]

I have been using the ASI1600 as well as the SX 694, and prefer the SX. The amp-glow on the ASI does calibrate out fairly easily, but I had the devil's own time trying to calibrate it out of the ASI 183.

My next camera is likely to be a 16200 CCD, as I think CMOS isn't there yet unless you go to stupidly and ruinously expensive professional types, e.g. FLI Merlin 4040.