Optional stretching of 12 bit s image saved using the FITS format

A place to report problems and bugs in SharpCap
Forum rules


If you have a problem or question, please check the FAQ to see if it already has an answer : https://www.sharpcap.co.uk/sharpcap-faqs

Please also read about Troubleshooting USB Issues before posting.

*** Please do not post license keys - please report any problems with licensing to 'admin' by private message ***

Please include the following details in any bug report:

* Version of SharpCap
* Camera and other hardware being user
* Operating system version
* Contents of the SharpCap log after the problem has occurred.
[If SharpCap crashes, please send the bug report when prompted instead of including the log]
Post Reply
db48
Posts: 21
Joined: Mon Feb 27, 2017 1:24 pm

Optional stretching of 12 bit s image saved using the FITS format

#1

Post by db48 »

Hi,
I tried to use the new feature of SC 3.1.5047 related to the optional stretch of a 12 bits image when saved using the FITS format (RAW 16 colour space). I use a ZWO ASI 174MMC camera with a 12 bits ADC onboard. However the saved FITS image is always stretched to 16 bits, indipendently from the fact that I check/uncheck the corresponding button in the General Setting menu. Where am I wrong?
User avatar
admin
Site Admin
Posts: 13173
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: Optional stretching of 12 bit s image saved using the FITS format

#2

Post by admin »

eeek - turns out that's Altair cameras only at the moment as the other cameras do not currently report their true bit depth. I can see an API that looks like it may work for QHY, but nothing for ZWO :(

Better update the UI to flag this limitation for now - thanks for the report.

cheers,

Robin
User avatar
admin
Site Admin
Posts: 13173
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: Optional stretching of 12 bit s image saved using the FITS format

#3

Post by admin »

Having looked into this further, there is no obvious way to get the ADC bit depth from the SDK for ZWO or QHY cameras. I could use the values calculated by sensor analysis, but that would require (a) people to do sensor analysis before this could work and (b) some substantial changes to the code... Both of these would rule that option out for the current phase of development where I am fixing bugs and making small, safe change if necessary.

I've contacted both manufacturers to see if they can provide this info in a future version of their SDK.

cheers,

Robin
User avatar
oopfan
Posts: 1321
Joined: Sat Jul 08, 2017 2:37 pm
Location: New York
Contact:

Re: Optional stretching of 12 bit s image saved using the FITS format

#4

Post by oopfan »

Confirmed that saving image to native 12 bits works for Altair 290M.

Thank you.
Post Reply