8 replies to this topic

[Orion58]

Hello CNers

 

I will (weather permitting of course) be imaging the conjunction on Dec 21 from my observatory.  Due to the fact that the planets will be low in the SW etc I may need to get some images while the planets are a bit higher and there is still some light in the sky.  The filters I am considering using are a Planet Pro 742 or a Baader IR Pass (685).  I also have regular LRGB filters along with Ha, SII & OIII (all 3nm).

 

I would appreciate any advice on imaging before "dark".

 

Clear skies

Edited by Orion58, 02 December 2020 - 12:23 PM.

[nighthoek]

I've done a "little" imaging while the sky was not totally dark.  I was using a ZWO ASI462MC with an IR blocking filter and the images were fine, no difference than doing it with total darkness.  I was working at f/30 with the barlow in the imaging train.

[Astrophotonics]

I'm also using a ASI 462MC coupled with a ZWO Atmospheric Dispersion Corrector, going to skip using an 8" SE and use a E.S. 127mm Triplet for sharpest possible result, not sure if i'm going to use a barlow seems to frame up nice without it.

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[Orion58]

Thanks guys.  I should have mentioned I'm planning on using my Esprit 120 f/7 @ 840mm and possibly my 1.5x barlow if conditions permit.  As low as the planets will be and this being Wisconsin using a barlow is perhaps wishful thinking.  Even without a barlow it frames nicely with my FLIR Chameleon 3.

 

I've never used this combination before - I'd normally use the Edge11 - but it's too much for this application.  I'm set up for a trial run tonight.  I'll try using both filters I mentioned and see how they compare.  Strangely, the weather forecast is for a stretch of calm, somewhat clear weather, so I hope to make the most of it and get my "final plan" in place.

 

Astrophotonics:  very nice images - nicely processed.

[dfva]

I've been wondering if the difference in brightness between the planets is going to make this difficult to image. My limited attempts to image the planets required different settings for each planet.

 

Anyone have any thoughts or advice on this?

[Orion58]

I've been wondering if the difference in brightness between the planets is going to make this difficult to image. My limited attempts to image the planets required different settings for each planet.

 

Anyone have any thoughts or advice on this?

 

That same question popped into my head at about 3am last night... Exposing Jupiter properly would lead to a "quite dim" Saturn.    My preliminary thoughts on this would be to make the videos in pairs.  Properly expose Jupiter for say, 30 sec, then expose Saturn properly for 30 sec (or whatever times you choose) and then combine them in Photoshop (or similar).  I've never done anything like that before but I assume there is a way.   

 

These are the things I hope to practice in the days prior to Dec 21. 

[Tom Glenn]

The exposure shouldn't be a problem.  Saturn will be dimmer than Jupiter, but when stacking thousands of frames, you gain incredible leverage with dynamic range.  If Jupiter occupies a 90% value of the maximum histogram, then Saturn will probably be at 40% or even lower, but this will still be perfectly fine to raise the brightness up with a curves adjustment.  Part of the appeal of an event like this is to document the real differences between the two objects.  The danger of a Photoshop cut and paste job is that it will end up looking artificial, which of course could be done even without the conjunction.  

[Kokatha man]

Specifically for the ZWO & FireCapture users, make sure you are setting the brightness at "0" when imaging in a bright sky background...under the "cog" symbol in the "More" menu.

[dcaponeii]

Specifically for the ZWO & FireCapture users, make sure you are setting the brightness at "0" when imaging in a bright sky background...under the "cog" symbol in the "More" menu.

You realize I hope that EVERY time you (and a few others too) type a post I learn something new.  Had no idea that setting even existed!!  Thank you