1336 replies to this topic

[AstroGabe]

Here's my first light with this camera.  I was floored by the results.  I started this project with my QHY16200A, and later compared the same optics/exposure w/ the ASI6200MM, and it was a night and day difference.  I also did a quick comparison shot of the Veil nebula with gain=0 vs. gain=100, and saw a really big improvement.  

 

First light image:

 

Veil nebula gain comparison (sorry for the low quality - youtube conversion compressed it):

https://www.youtube....h?v=Yp0NDATssbc

 

OIII channel difference between ASI6200MM and QHY16200A - same optics and filters:

https://www.youtube....h?v=R0azVK24ytw

[gregbradley]

I am thinking of getting an ASI6200mm Pro.

But the earlier thread complaining of banding concerns me.

 

Was this resolved or is it something you have to contend with in processing the images?

 

Greg.

[txo]

I am thinking of getting an ASI6200mm Pro.

But the earlier thread complaining of banding concerns me.

 

Was this resolved or is it something you have to contend with in processing the images?

 

Greg.

I have no banding problems.

[Ruediger]

I have no banding problems.

I still see the banding, but only in extreme short exposures. Also the banding signal is only 2-3 ADU over the background signal. Hence it vanishes during stacking or longer exposure and only visible when stretching a an image with very low variance in signal. Do not get tempted to create bias or very short flats.

[gregbradley]

Thanks for the feedback. So its not a real problem.

 

Greg.

[thekubiaks]

Same,  no problems,  great camera.

[gregbradley]

There has a been a lot of tall about the opening size. Is the M68 mounting plate now standard with the latest shipments or is it an extra?

 

 

Greg

[AnakChan]

Looking at the ZWO page, it seems M54 is still the standard. It wouldn't only be just the M54 that they'd have to swap out. They'd have to change the M54-M48 extender that comes with it.

 

On a separate topic, anyone has any thoughts of using a Chuwi Larkbox (Celeron J4115) as an acquisition miniPC for the ASI6200MM? It has 6GB RAM and takes M.2 SSD's. Does one need beefier i5-core processors for the ASI6200MM just acquisition & guiding, or would the J4115 do?

 

https://www.techrada...-client-mini-pc

Edited by AnakChan, 02 August 2020 - 11:45 PM.

[Lead_Weight]

Looking at the ZWO page, it seems M54 is still the standard. It wouldn't only be just the M54 that they'd have to swap out. They'd have to change the M54-M48 extender that comes with it.

 

On a separate topic, anyone has any thoughts of using a Chuwi Larkbox (Celeron J4115) as an acquisition miniPC for the ASI6200MM? It has 6GB RAM and takes M.2 SSD's. Does one need beefier i5-core processors for the ASI6200MM just acquisition & guiding, or would the J4115 do?

 

https://www.techrada...-client-mini-pc

This one looks really good to me, and would probably be the one I purchase. Already has a WIFI extender, and is pretty small.

 

https://www.amazon.c...90YCRRVDD1263W6

 

Considering you can get away with a 4GB Raspberry Pi for the ASI6200, I don't think you need something super powerful...just something with lots of storage.

Edited by Lead_Weight, 03 August 2020 - 08:53 AM.

[AnakChan]

This one looks really good to me, and would probably be the one I purchase. Already has a WIFI extender, and is pretty small.

 

https://www.amazon.c...90YCRRVDD1263W6

 

Considering you can get away with a 4GB Raspberry Pi for the ASI6200, I don't think you need something super powerful...just something with lots of storage.

 

That's my thinking that if a RPi4 can manage the ASI6200, I don't think I'd need beefy PCs. I won't be doing post processing but I'm just not certain if the likes of autofocusing routines would be CPU heavy.

 

Considering these miniPCs are pretty cheap, I guess it's no harm in giving one of these a shot.

[Lead_Weight]

I'm facing some calibration issues that I just don't understand. This was first light for me with this camera. 

 

Here's what I shot:

Lights HA 120s Gain 100 offset 50 Bin2x2

Darks 120s Gain 100 offset 50 Bin2x2

Bias .2s Gain 100 offset 50 Bin2x2

Flats HA 25k 1.39s ADU Gain 100 offset 50 Bin2x2

FlatDarks HA1.39s ADU Gain 100 offset 50 Bin2x2

 

This is my calibrated result every time. I've tried with bias, and flat darks, and both. I've tried flat ADU values ranging from 2k to 25k resulting in no difference. I've processed with Pixinsight, and with Astro Pixel Processor. I'm wondering if the Binning has something to do with things being read incorrectly, as that's the only difference I'm seeing compared to other users.

 

Here's 1 frame from each of the above if someone can tell me if there's a mis-match somewhere. 

 

Edited by Lead_Weight, 08 August 2020 - 09:06 AM.

[FredOS]

Why do you need a bias ? With Flatdarks, you shouldn't need to use a Bias. Have you tried calibrating your Flats with Flatdarks and then lights with your masterDark and MasterFlat ?

have a look through https://pixinsight.c...ibration.11547/

Frederic

[txo]

I'm facing some calibration issues that I just don't understand. This was first light for me with this camera. 

 

Here's what I shot:

Lights HA 120s Gain 100 offset 50 Bin2x2

Darks 120s Gain 100 offset 50 Bin2x2

Bias .2s Gain 100 offset 50 Bin2x2

Flats HA 25k 1.39s ADU Gain 100 offset 50 Bin2x2

FlatDarks HA1.39s ADU Gain 100 offset 50 Bin2x2

 

This is my calibrated result every time. I've tried with bias, and flat darks, and both. I've tried flat ADU values ranging from 2k to 25k resulting in no difference. I've processed with Pixinsight, and with Astro Pixel Processor. I'm wondering if the Binning has something to do with things being read incorrectly, as that's the only difference I'm seeing compared to other users.

 

Here's 1 frame from each of the above if someone can tell me if there's a mis-match somewhere. 

 

Screen Shot 2020-08-08 at 8.56.01 AM.jpg

Try using just darks and flats. I had similar problem until I settled on those two. And when using PI do not forget turn off  "Calibrate" and "Optimize" checkboxes.

Edited by txo, 08 August 2020 - 09:37 AM.

[Lead_Weight]

Why do you need a bias ? With Flatdarks, you shouldn't need to use a Bias. Have you tried calibrating your Flats with Flatdarks and then lights with your masterDark and MasterFlat ?

have a look through https://pixinsight.c...ibration.11547/

Frederic

I'm only using one or the other. But have tried both. I've calibrated hundreds of images with other cameras both color and mono, but this one is stumping me.

[Lead_Weight]

Try using just darks and flats. I had similar problem until I settled on those two. And when using PI do not forget turn off  "Calibrate" and "Optimize" checkboxes.

Hmm, same result in both APP and PixInsight. So, something must be wrong with the darks or flats. 

[bulrichl]

Hi Andrew,

 

the FITS header tells a different story:

                  gain      offset
bias 0.032 ms:    100         1
dark 120 s:       100         1
dark 1.39852 s:   100        50
Flat: 1.39852 s:  100        50
Light 120 s:      100        50

The flat dark (1.39852 s, offset 50) matches up the flat frame, but the dark frame (120 s, offset 1) does not match up the light frame.

 

You'll have to capture new dark frames (120 s) with matching offset of 50. Delete the old dark frames (120 s) and the bias frames (bias frames are not needed).

 

As a workaround, I calibrated the flat frame only with the appropriate flat dark (1.39852 s). For the light frame, I did the subtraction of the dark frame in PixelMath and tried to correct for the mismatched offset:

NGC_7380_Light_HA_120_secs_2020_08_07T23_34_05_034-Dark_120_secs_2020_07_22T00_17_43_051-490/65536 
Create new image: NGC_7380_Light_HA_120_secs_2020_08_07T23_34_05_034_cal

Then I calibrated the result of the PixelMath equation with the calibrated flat frame (only performing the flat field correction). The result looks OK, see appended screen section. This workaround is not recommendable, it only shows that with matching calibration frames everything will work as expected.

 

Bernd

 

Attached Thumbnails

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[Lead_Weight]

You are a saint Bernd! Thank you so much for taking a look. I’ll reshoot my darks. Should be easy enough. Really surprised the offset value caused that result. I had shot the darks when I first got the camera, probably not noticing the offset value. 

[Lead_Weight]

Success with new darks! 

 

The Wizard Nebula HA Chroma 3nm, shot with my EdgeHD 11, bin 2x2.

 

[bulrichl]

I'm glad that it worked for you. By the way: nice detail in your image.

 

Bernd

[abasak]

Don't know if this is the right question to ask in this thread...

 

First of all, finally after weeks of waiting i got my ASI6200mm and the kit delivered. 

 

As i assembled the EFW, OAG and the ASI6200MM, I realized I will not be able assemble and disassemble every night for my imaging session. Because i live in apartment, i will need to drive down to a relative dark sky (Bortle 5-6) for my imaging session. I was wondering if any one has explored the idea and have solution for carrying case,(preferably a hard shell) to contain the whole kit in assembled manner.

 

Then all i need to do is take it out and just attach it to my OTA.

 

Thanks in advance.

[ezwheels]

I put a M68 (M) dust cap on the OAG and disconnect the cables from the 6200 camera to the FW and OAG camera and then place this whole kit into a soft shell Leica slide projector case that I had in the closet. For the OTA I have a Baader M68 female dust cap that gets threaded onto the back. This goes in its own case for travel as well. Threads back together quickly and accurately with tape index markers that span the two components. 

[Tangled Cords]

Hello All,

 

I'm currently using the AP Nose piece adapter for CCD field flatteners and telecompressor (part #ADATCC2) to attach my ZWOASI6200MM camera. The AP Nose Piece adapter makes is very difficult to adjust the telecompressors 1mm spacing allowance. The three compression screws on the adapter can easily create tilt issues plus sliding the camera/filter wheel in out with any accuracy is difficult to say the least. Does anyone know if there is an accurate threaded spacer option available to match the AP field flattener and quad telecompressor to the ZWOASI6200MM&FilterWheel?

 

Thanks in advance.

[rockstarbill]

Precise Parts is the best route.

 

If you plan to use the provided 22.1mm spacer, then the min length adapters are the same for the reducer and flattener. If you remove that 22.1mm spacer the min length is NOT the same, the flattener adapter will be about 2.6mm longer. 

[DaveB]

This one looks really good to me, and would probably be the one I purchase. Already has a WIFI extender, and is pretty small.

 

https://www.amazon.c...90YCRRVDD1263W6

 

Considering you can get away with a 4GB Raspberry Pi for the ASI6200, I don't think you need something super powerful...just something with lots of storage.

I don't want to stray too far off topic, but just one word of caution here. I have a stick PC (Atom processor), and although it is slow, it performed fine for an at-the-scope acquisition PC. However, when I tried to use the external SD card to download images to, the download times were much, much longer. If you're going to use something like the stick PC in the link above with a 6200 (and it's huge subs), be aware that you'll only have on the order of 10G of internal storage after Windows and other software is loaded. Maybe this model is better than the one that I used, but having to download subs to the SD card was not viable on the one that I used. I would move them over to SD after each session to save storage.

[FredOS]

How efficient is this camera ?

I have an ASI6200 and was doing flats with my Alnitak flat panel which is a very precise device. I was using Gain 0 and offset 50 and I was very surprised that to achieve about 25000 ADU it was taking about 1/3 more time than with my FLI16200 camera where I was targeting a higher 39000 ADU. Quick conclusion would be that it is about 50% less efficient. I tried this with LRGB and narrowband filters and the results were similar. Isn't this a little odd for a camera touted as having very high QE ?

I'll reach out to ZWO to find out a little more about what could be an explanation for this.

For comparison the FLI16200 has gain of 0.63 and full well of about 39,000. ZWO at gain "0" is 0.78 e/Adu.