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Alveprinsen

Orion - Widefield tests.

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Since my scope was all iced up today, I turned to my Vixen Polarie and my Takumar Pentax Super Multi Coated 200mm vintage lens instead... I did use my modified and cooled EOS 600D tho...

So, I had a few clouds roll in after a while, which really messed things up. I've stacked 25%, 50%, 75% and 100% of the images below for your viewing pleasure.

Exposure is at approx 45 minutes combined. Different exposures are: 15sec, 30sec, 60sec and 120sec. I've done all darks, bias and flats.. ISO 1600.

post-27347-0-16797400-1418520713_thumb.j

And here is the final image. I used the 50% stacked one. You can see the clouds creating a nasty halo effect around the brightest stars. :(

post-27347-0-97920400-1418520761_thumb.j

Surely gonna do some more widefield of this area once I get real clear skies... :)

Sincerely, Alveprinsen.

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Very nice, you also got the flame nebula, horse head and running man.

In mine i can't see the horse head.

what mod did you make to your camera?

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Awesome image Ambassador Kosh :grin: I suspect you've visited many systems within that shot. Could you go wider and get barnard's loop too? 

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I've just been imaging Orion but with a 135mm Super Takumar :D

I had exactly the same blue haloes around the brightest stars, I'm guessing thats either cloudy haze as you said or CA as you would with an achromatic refractor? If so, you can get filters to cut out the haloes

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I've just been imaging Orion but with a 135mm Super Takumar :D

I had exactly the same blue haloes around the brightest stars, I'm guessing thats either cloudy haze as you said or CA as you would with an achromatic refractor? If so, you can get filters to cut out the haloes

The 135mm seems to be popular...

I dont know about the blue halos, but I bet the purple around the lesser stars are CA. I bought this lens because I had read that it was basically CA free... with its super-multi coating and stuff. Oh well, what can one expect from a.. what, 35? year old lens...

I did clock a few more hours on the thing today though, and this is the result:

post-27347-0-61269000-1418708351_thumb.j

Got a really weird artifact there. I wonder what that is...

I've been doing 180 sec exposures only this time. Its the highest I can go with my Vixen Polarie startracker... :) I tried 240, but the stars started trailing.

Seems I've hit the point of diminishing returns... Gonna need those 10 minute exposures to really bring out the fainter dust and stuff.

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Awesome image Ambassador Kosh :grin: I suspect you've visited many systems within that shot. Could you go wider and get barnard's loop too? 

*weird voice* - "yes"

I guess I could hook up the 55mm F1.4 and see if I could fit the loop. Would be an interesting project for a relatively bad night with short cloudless window.

I had like 7 hours cloudless tonight, and almost no wind. Too bad I had taken the 200PDS inside to de-frost the damn mirrors. I could've gotten some serious data on a couple of other object that interest me a great deal more than the old Orion constellation. Truth be told, I am quite tired of it... But without using the NEQ6 Pro and a real scope, targets are kinda limited with the Polarie and 200mm prime lens.. :)

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The 135mm seems to be popular...

I dont know about the blue halos, but I bet the purple around the lesser stars are CA. I bought this lens because I had read that it was basically CA free... with its super-multi coating and stuff. Oh well, what can one expect from a.. what, 35? year old lens...

I did clock a few more hours on the thing today though, and this is the result:

attachicon.gifedited2.jpg

Got a really weird artifact there. I wonder what that is...

I've been doing 180 sec exposures only this time. Its the highest I can go with my Vixen Polarie startracker... :) I tried 240, but the stars started trailing.

Seems I've hit the point of diminishing returns... Gonna need those 10 minute exposures to really bring out the fainter dust and stuff.

I would guess it could be a lens flare.

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I would guess it could be a lens flare.

Hmm, not an entirely unreasonable assumption...

However... What on earth could've made that.. Unless I accidentally flashed the lens with my flashlight in one of the photos...

Damn, now I need to look through all of them.

I selected "use 70% of the best images..." in DSS. Shouldnt this have been filtered out if there was only one or two frames like that?

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Don't know about DSS and how it decides.

I normally scan through my subs in Canon DPP and weedout the ones that look obviously bad, then I let DSS stack 100%

BTW

Even with the artifact there is nice detail in there, some of the stars look quite big.

I have a few old lenses but after messing with them always go back to the Canon 200mm L or the Sigma 105mm macro for wider fields.

May be the old ones I got are not very good versions.

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That artefact has quite sharp edges... Were you using a decent sized dew shield? Considering your ambient winter temperatures it's probably worth getting some dew heaters for the various exposed parts of your imaging setups :)

Louise

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Still learning DSS. I've found throwing away low scores is always justified, But individual sub inspection will find a few more rejects. Very high scores are also suspect as DSS has been found to give high scores to subs where clouds have moved in.

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Still learning DSS. I've found throwing away low scores is always justified, But individual sub inspection will find a few more rejects. Very high scores are also suspect as DSS has been found to give high scores to subs where clouds have moved in.

It seems the score is how big and round stars are.

I have stacked subs that had light cloud but the score was'nt much different than cloudless subs.

Normally I throw out subs that look a lot brighter, they are the cloudy ones.

I don't throw out aircraft or satellite trails as I always use sigma clip.

As a bare minimum I want at least 12 300sec subs and ideally 24 or more 300sec subs.

These amount of subs are typical for my local sky conditions with the setup at around f4 and iso1600.

BTW

I have fairly bright skies, moderate LP and it's very rarely clear.

There is nearly always some sort of haziness, cloud and contrails. :sad:

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That artefact has quite sharp edges... Were you using a decent sized dew shield? Considering your ambient winter temperatures it's probably worth getting some dew heaters for the various exposed parts of your imaging setups :)

Louise

Its a 200mm vintage prime lens from Takumar Pentax... It has a sun-shield or whatever that is reasonably large. I've also used a dew heater on it. ;) It is possible that stray light from the side has resulted in those large circles - most likely the outline of the sun shield? ... I dont see any other posibility.

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It seems the score is how big and round stars are.

I have stacked subs that had light cloud but the score was'nt much different than cloudless subs.

Normally I throw out subs that look a lot brighter, they are the cloudy ones.

I don't throw out aircraft or satellite trails as I always use sigma clip.

Thanks! I will have to keep an eye out for this then. guess I need to go through my subs myself and delete the worst ones by hand.

I will have to look into this whole sigma clip thing too... havent used that before I think - seeing as I dont even know what it is. :p

Gonna check it out next time I stack images. hopefully this year, but... most likely in January... :p

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Its a 200mm vintage prime lens from Takumar Pentax... It has a sun-shield or whatever that is reasonably large. I've also used a dew heater on it. ;) It is possible that stray light from the side has resulted in those large circles - most likely the outline of the sun shield? ... I dont see any other posibility.

Think I'd fit a decent length dew shield - some sort of diy one, maybe. I use a 25cm black non-reflective paper shield over my 80mm scope, a 45cm one on the 150pds. I even use a 15cm shield on my 50mm finder guider and a 25cm one on my 60mm guidescope. They all help to keep stray light out. I also have my 1100d viewfinder taped over, and the primary mirror end of my 150pds is covered over to prevent stray light coming in the base. I've not gone to the extent of flocking anything - yet!

I'd really like to get a 200mm SMC Takumar http://en.wikipedia.org/wiki/Takumar Maybe I'll treat myself in the new year, if I can find a decent one - perhaps when (if?) I get my mono 1100d back from JTW... :)

Louise

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Here's mine with the Super Takumar 135mm, was a quick test of the lens between clouds.

6 x 120s, no darks or flats.

Processed in AAv5

post-15858-0-88189600-1418989759.png

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Here's mine with the Super Takumar 135mm, was a quick test of the lens between clouds.

6 x 120s, no darks or flats.

Processed in AAv5

Looking good. Considered working with layers as to not over expose? Was mainly thinking of the M42 core... Not that mine is any better. I ought to have taken some shorter exposures as well.... :)

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Very nice, you also got the flame nebula, horse head and running man.

In mine i can't see the horse head.

what mod did you make to your camera?

Oops... just noticed I didnt reply to this one.

The camera is a full spectrum Canon EOS 600D from CentralDS (google'em...)

The two main things about the camera is that it is full spectrum, and cooled with peltier cooling... so on a regular winter night when the outside ambient temperature is about -5 to -10 C, the chip runs at a constant -29 to -34 degrees C.. so no noise basically...

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