Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_30_second_exp_2_winners.thumb.jpg.b5430b40547c40d344fd4493776ab99f.jpg

russellhq

QHY8L - Good Idea/Bad Idea?

Recommended Posts

I can see your logic. I'd be interested in a shoot out...

Olly

I'm backing Olly :D  Yes, I've done NB with an OSC and got reasonable results but "mono" is "an entirely different ball game".  Ha gets 25% sensitivity, and OIII gets 50% whilst SII is quite hopeless.  And yes, resolution is also a quarter ie. half in X and half in Y.  I used to do bi-colour with super setpoint cooled DSLR but couldn't touch the dimmer DSOs that I capture naowadays.

Share this post


Link to post
Share on other sites
Guest

I gather from the comments here that nobody is proposing to replace omnichrome cameras with OSC's where narrow band is concerned but the fact it can be done is news to me and really useful too.

I don't use omnichrome cameras due to the usual reasons of UK weather and wanting to finish processing my images within a reasonable time (i.e. impatient :-)

The idea that I could enhance my images a bit with narrow band filters seems like fun - I'm going to give it a shot....although I'm not getting involved in any shootouts with Olly :-)

David

Share this post


Link to post
Share on other sites

Aha, the first use of 'omnichrome!!!'  :grin:  However, we've moved on since that word was invented!!!

You certainly can improve OSC images with NB. It's slow but possible.

Olly

Share this post


Link to post
Share on other sites

Hello guys,

do you know if the QHY8L works only on USB (power i mean), with TEC off ?

Because i have connected it, but i get only images of small black dots on a white background..

I have bought today a supply source of 12V - 5A and will test tonight. I hope the camera is ok..

Thank you,

Andrew

Share this post


Link to post
Share on other sites

You need the power connecting.  Also read the manual and use the correct sequence to connect the cables.

Connection Sequence:

  • Connect USB cable from camera to PC
  • Connect 9-pin cable from camera to DC201
  • Connect 12V power to DC201

4.Disconnection Sequence:

  • Disconnect 12V input power from DC201
  • Disconnect 9-pin cable from camera
  • Disconnect USB cable from PC
  • Like 1

Share this post


Link to post
Share on other sites

Also, after you connect the USB cable, load up your capture software and set your cooling point. My camera always defaults to 50% cooling power. So if I don't change the setting in the software first before connecting power, as soon as I connect the power the TEC comes on at 50% and then it takes me longer to get the cooling to my desired set point.

Share this post


Link to post
Share on other sites

Thank you guys,

i got the power supply, everything is fine now, cooling is ok; i followed the procedure for setting gain and offset..but due to fog i must postpone taking the first picture :)

Clear skies!

Share this post


Link to post
Share on other sites

Just received the last Qhy8l from stock from Bern,seem to be selling well,can anybody suggest a light pollution filter for this model? would the ldas p2 be the best choice.

Share this post


Link to post
Share on other sites

IDAS P2. If you buy another you'll always wonder how much better the IDAS is and end up buying it. Best just jumping straight in :)

  • Like 2

Share this post


Link to post
Share on other sites

I use the bog standard 2" skywatcher LP filter on my original QHY8 - works pretty well.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the recommendations.Im looking at the adapter that Bern supplied me,Whitch he said was the correct spaceing to use with my celestron 6.3 focal reducer,the one section has brightstar  30mm spacer sku 1890 printed on it,unless i split the section then i cant see were the filter would sit ,the internal thread diameter is 42mm,dose this seem right, flo lists either a 1.25 or 2inch and up,iz confused,any help welcome.post-8423-0-77388500-1385075217_thumb.jppost-8423-0-34955400-1385075431_thumb.jp

Share this post


Link to post
Share on other sites

I use the bog standard 2" skywatcher LP filter on my original QHY8 - works pretty well.

Same here, seems to be ok for my needs.

Share this post


Link to post
Share on other sites

This is what the QHY8L is capable of M42 Orion Nebula 1 x 240 secs subs processed in PI while waiting for the clouds to disappear.  Taken with a QHY8L,SW ED80,GT-EQ6,Astronomik CLS Filter (not IR blocked) guided with 9 x 50 finder guider with a QHY5. :grin:

Dave

post-17240-0-92097000-1385386512_thumb.j

Share this post


Link to post
Share on other sites

This is what the QHY8L is capable of M42 Orion Nebula 1 x 240 secs subs processed in PI while waiting for the clouds to disappear.  Taken with a QHY8L,SW ED80,GT-EQ6,Astronomik CLS Filter (not IR blocked) guided with 9 x 50 finder guider with a QHY5. :grin:

Dave

Nice result though the question of blue signal is again raised by this capture. There is far more red than blue being recorded here. (Note the outer part of the Running Man and the bright stars lower left of the main nebula. Both are quite strong in blue.) COuld this be the CLS? I don't know.

Olly

Share this post


Link to post
Share on other sites

Nice result though the question of blue signal is again raised by this capture. There is far more red than blue being recorded here. (Note the outer part of the Running Man and the bright stars lower left of the main nebula. Both are quite strong in blue.) COuld this be the CLS? I don't know.

Olly

Thanks Olly that's the one thing that I have noticed is that it picks up more red than any colour is there anyway of boosting the blue?

Dave

Share this post


Link to post
Share on other sites

Yes it is Olly!! I got a strong reddish colour on M42 when using my TS CLS filter, it's alright, but I've quickly opted for the Hutech IDAS LPS-P2 filter instead as the red colour can be quite annoying!! This Hutech is around £200 very expensive but it doesn't add any colour at all, so worth the money definitely!! :laugh:

Share this post


Link to post
Share on other sites

Thanks Olly that's the one thing that I have noticed is that it picks up more red than any colour is there anyway of boosting the blue?

Dave

There is. You could work on just the blue channel in Ps, manipulating it in curves to lift it. It's tricky but possible.

Olly

  • Like 1

Share this post


Link to post
Share on other sites

Yes it is Olly!! I got a strong reddish colour on M42 when using my TS CLS filter, it's alright, but I've quickly opted for the Hutech IDAS LPS-P2 filter instead as the red colour can be quite annoying!! This Hutech is around £200 very expensive but it doesn't add any colour at all, so worth the money definitely!! :laugh:

That very interesting with the Hutech IDAS LPS-P2 filter it block's IR would that cause a problem as the QHY8L is already IR blocked with the glass in the ccd body. Is this the same filter as it's only £155 http://www.firstlightoptics.com/light-pollution-reduction-imaging/idas-p2-light-pollution-suppression-filter.html.

Dave

Sent from my iPad using Tapatalk

Share this post


Link to post
Share on other sites

Nice result though the question of blue signal is again raised by this capture. There is far more red than blue being recorded here. (Note the outer part of the Running Man and the bright stars lower left of the main nebula. Both are quite strong in blue.) COuld this be the CLS? I don't know.

Olly

I meant to say lower RIGHT of the nebula. Sorry. They have significantly blue haloes, partly from our optics but partly (I suspect) from reflection. http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-rNfQT5R/0/X3/M42%20WIDE%202FLsV3-X3.jpg

Olly

Share this post


Link to post
Share on other sites
Guest

Thanks Olly that's the one thing that I have noticed is that it picks up more red than any colour is there anyway of boosting the blue?

Dave

I have to boost the blue channel and weaken the red/green with every process - there are a couple of ways I've found that work really well and mean it's not such an issue

As for the LP filters adding red - I ran without the neodymium filter at Kelling and had the same sort of processing task as with it - lots of red and the blue very weak.

Happy to discuss if you'd like to send a pm - don't want to kill this thread by going too far "off piste" LOL!

David

Share this post


Link to post
Share on other sites

An important point; no filter ever adds anything. All filters filter, meaning they are sieves. That is, they reject. They are subtraction only. In this case they seem to be rejecting green and blue more than they reject red.

Olly

Edited by ollypenrice

Share this post


Link to post
Share on other sites

I have to boost the blue channel and weaken the red/green with every process - there are a couple of ways I've found that work really well and mean it's not such an issue

As for the LP filters adding red - I ran without the neodymium filter at Kelling and had the same sort of processing task as with it - lots of red and the blue very weak.

Happy to discuss if you'd like to send a pm - don't want to kill this thread by going too far "off piste" LOL!

David

Thanks I will take you up on the offer I will send a PM.

Dave

Share this post


Link to post
Share on other sites

Hello,

last night i managed to image the M31, unfortunately the image looks pretty bad after calibration and stacking in DSS.

there are 6x300sec light, 5 darks, 20 bias; no flats..

My gain was 6 with 114 offset, temperature set at -10 C.

First thing is that the raw .fit images seem to be gray and not color...

I am not sure what i am doing wrong.. please see the stacked image at the below link, but it's pretty big around 80 MB.

I would appreciate any advice..

https://drive.google.com/file/d/0B7abYsk7FXHRZlNQMHdSMkdEZUU/edit?usp=sharing

Thank you,

Andrew

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.