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Lost my M42 virginity last night!

dlp

By dlp
in Imaging - Deep Sky

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dlp

dlp

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Waited up for Orion to reach an accessible area of the sky last night and managed to come up with the following images, my first of M42, just differently treated in PS. 10 frames 25s ISO800, no darks flats or bias yet.

Wonder which you think is 'best' (if that's not an overstatement), and any comments welcome!

David

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Paxo

Paxo

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As Kevin has said, add some flats to your processing and you'll be able to turn these good images into excellent ones. You have recorded some excellent detail and your tracking is spot-on.

Looking forward to seeing more of your work in the future.

Steve

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dlp

dlp

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Thank you - very much! I'm a little concerned about the amount of vignetting in the image - below is a quick grab from a raw file where I've deliberately clipped the blacks so you can see the vignette on the whole frame. I've just recently fitted a moonlite, so I'm a bit worried I've got something wrong in the image train. I used a SW coma corrector & SW LP filter on the camera.

Is this normal please? (I know good flats will improve it but I don't want to be correcting for things that shouldn't be there!)

David

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dlp

dlp

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It's the T mount that came with the SW 2" coma corrector (and directly screwed to it), and the 2" LP filter is screwed on the end of that. The LP filter screw is very low profile.

Hope this is useful.

David

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Coolhandjo

Coolhandjo

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You did a pretty good job of containing the core as its not too blown out and you still have enough stretch to get the outer detail so well done. Stars are tight and full of depth so well done there too. Make sure any filters you use are close to the chip to prevent excessive vignetting. Also A DSLR chip may work best at about 55mm from any coma corrector to prevent vignetting and to get a focul length thats not altered.

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dlp

dlp

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Right, inspired to do better, I've been playing. I took darks/flats/bias and eventually managed to get calibrated images in the PI trial. I had a play with just about every feature I thought might be useful, then did some final tweaks in PS.

Is this better do you think?

Below this I have added a levels hacked copy of one of my flats - the vignetting seems to be offset heavily - is this an indication that my secondary is not aligned properly?

David (WHO WISHES PIXINSIGHT WAS A LOT CHEAPER!)

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Shibby

Shibby

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Nice job David. Until you start taking flats, grab yourself a copy of GradientXTerminator, it's a quick and easy fix :) Though I still recommend cropping slightly before using.

Edit: You posted the new version while I was typing. And it's a cracking image, well done!

That should be fine and with flats you should be able to correct the vignetting. The DSLR chip is just about ok with T thread fittings but you will get some vignetting.

Unless I'm mistaken, the SW coma corrector actually uses a wider adapter than a T-thread. Is the level of vignetting exaggerated by the 2" LP filter?

The CC and LPR are on my Christmas list... I'm impressed by your encouraging star shapes David!

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dlp

dlp

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Thanks Lewis - yes the CC uses a 'special' adapter to fit the 2" size. I haven't done any flats without the LP filter, but will give it a try. Don't think that would explain the offset though, and I'm pretty much stuck with the filter!

David

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dlp

dlp

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I noticed a certain whispiness about certain areas of the above image, and this seems to be created in converting from 32 to 16 bit in CS5 - originally I chose a 'photorealistic' intent on the HDR Local adaption dialogue. This new one uses 'Saturated' instead which produced a darker background, but not clipped.

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Shibby

Shibby

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I'm not an expert, but I'd guess your secondary mirror is offset - this can be adjusted during collimation. I'm not sure, but I think some newtonians are deliberately offset. Perhaps someone can confirm/correct me there...

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SlipperySquid

SlipperySquid

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Yes some fast newtonians have an offset, and judging from your pics your stars look really good to me so I'd say that the collimation is excellent! :)

I have the same scope and suffer from a lot of coma so I think the old coma corrector is my next buy!

Really good work by the way! I just need to win the lottery so I don't have to go to work and miss all the clear skies :D

Look forward to seeing more pics!

Matt.

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dlp

dlp

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Thanks Matt - useful info, so I can relax a bit now!

I bought the coma corrector after my 1st ever dslr photo of the double cluster showed some rather strange shapes, and it's been worth it.

Lottery? You and me both, but the odds are if you buy 2 tickets a week for 148,000 years, you should win a jackpot once.

David

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