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What is this a picture of please? -taken last night

A40farinagolf

By A40farinagolf
in Imaging - Deep Sky

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LukeSkywatcher

LukeSkywatcher

Posted
Posted

My first thought was also M1 (Crab Nebula).

https://uk.images.search.yahoo.com/images/view;_ylt=A2KLj9GEFepUKUgALw5NBQx.;_ylu=X3oDMTI0OWo1c3FpBHNlYwNzcgRzbGsDaW1nBG9pZAMxYWQ5ZDhkODU2MTI0NWQ1ZmEwMmU4MTczODUyNGU1MQRncG9zAzI0MQRpdANiaW5n?.origin=&back=https%3A%2F%2Fuk.images.search.yahoo.com%2Fsearch%2Fimages%3Fp%3Dcrab%2Bnebula%26fr%3Dcrmas%26fr2%3Dpiv-web%26nost%3D1%26tab%3Dorganic%26ri%3D241&w=590&h=510&imgurl=www.calvin.edu%2Facademic%2Fphys%2Fobservatory%2Fimages%2FAstr110.Spring2006%2FDisselkoen-crabnebula.jpg&rurl=http%3A%2F%2Fwww.calvin.edu%2Facademic%2Fphys%2Fobservatory%2Fimages%2FAstr110.Spring2006%2FDisselkoen.html&size=21.1KB&name=%3Cb%3ECrab+Nebula%3C%2Fb%3E%2C+Stephen+Disselkoen&p=crab+nebula&oid=1ad9d8d8561245d5fa02e81738524e51&fr2=piv-web&fr=crmas&tt=%3Cb%3ECrab+Nebula%3C%2Fb%3E%2C+Stephen+Disselkoen&b=241∋=21&no=241&ts=&tab=organic&sigr=12pt94e0f&sigb=13d1uvt0i&sigi=12sogovtn&sigt=116qa2h9u&sign=116qa2h9u&.crumb=mgQuQamnT7J&fr=crmas&fr2=piv-web

I picked the above image to compare because it is also low resolution/detail but certainly has similar "dark" areas on both sides. I'm gonna put all my chips on the one number and go for M1.

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LukeSkywatcher

LukeSkywatcher

Posted
Posted

Thanks for the feedback and for identifying the crab nebula.

What do I need to do to make the images better?

I haven't tried guiding yet as I'm working up to it and want to get better at unguided first.

Your M42 is rather good. I think all you need to do (at a basic level) is experiment with exposure times and ISO settings and find a happy medium. Also try stacking images (lots of short exposures stacked ontop of each other using DSS).

If you can post your imaging details (exposure times,ISO setting etc), i'm sure someone more qualified can help more.

Your focus looks spot on in #1,2,4. Its a little off in #3. There is a bit of trailing in #3. Is trailing a focusing issue?, maybe not. Maybe just too long of an exposure.

Also think about your framing. You want the object of interest pretty much centred. Makes for a nicer image, but thats neither here nor there at the moment..........but keep it in mind for the future.

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  • 2 weeks later...
A40farinagolf

A40farinagolf

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Guiding is the life blood of deep sky imaging.That's about it...

Olly

I don't know anything about guiding yet however I know that I'll need to. Might sound like an unusual question but will I obtain results by guiding on an AZ CPC925 than a badly polar aligned AZ EQ6? What I'm getting at is will the guiding camera / software cancel out any errors in alignment.

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wuthton

wuthton

Posted
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I don't know anything about guiding yet however I know that I'll need to. Might sound like an unusual question but will I obtain results by guiding on an AZ CPC925 than a badly polar aligned AZ EQ6? What I'm getting at is will the guiding camera / software cancel out any errors in alignment.

You still need to be reasonably well polar aligned when guiding but you could kill 2 birds with one stone.

The popular guiding application PHD2 (OpenPHD) has a utility to help you drift algn.

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Oddsocks

Oddsocks

Posted
Posted

It amazes me just how good the images from a normal DSLR have become in recent years.....

Besides the technicalities of polar aligning and guiding you can improve your images dramatically by just carrying out basic levels adjustment in a photo editing program.

In the example below, using photoshop, the black point and mid point levels are adjusted for each of the three colour channels independently until the left side of each colour channel's histogram is aligned and the width of each histogram is roughly the same.

It is the quickest of all adjustments to make and takes just a few minutes but the resulting images look so much better once colour balanced....

Most photo editing software can do this.

 

 

 

 

 

 

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ollypenrice

ollypenrice

Posted
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Guiding with poor PA will recentre an image but will not stop it from rotating. An alt az mount is just an extreme case of a badly polar aligned one (unless you are using it at one of the poles. Brrrrr!)

Olly

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ollypenrice

ollypenrice

Posted
Posted

Hi Olly,

Many thanks and the penny has now dropped - doh!!!

As you say it's not just about keeping it in the centre of the image, the object will rotate and I hadn't thought about that.

Regards,

M

The example I usually give on courses is based on the constellation of Orion. As he rises the hunter is leaning to the left. As he sets he's leaning to the right. That's the rotation we're talking about.

Olly

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nucdoc

nucdoc

Posted
Posted

As a beginner like you I can attest that you can only get so much data from unguided acquisitions, I wish I had not wasted so much time with unguided imaging, and spent more time mastering guiding

Processing will also add a lot to your images, attached is your M42, processed as a JPEG (this limits how much I can pull out), this was background subtracted, color balanced, with some histogram and curve stretching in PixInsight.  As a beginner if you are willing to spent time with the tutorials you can get a lot of bang for your buck from PI

post-39396-0-15659700-1425674215_thumb.j

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