Quick one from last night beautiful skies here in Liverpool sorting out mount problems. It's finally behaving. 1 hour on each panel. Good seeing overall, but bit windy later during the evening. I pushed the processing to show a lot more of the outer nebulosity. Everybody know what the keyhole region looks like right? There are already awesome detailed crops of the area in these forums.
Very clear image of the faint HA in this region. I have literally spent years trying to image this object properly to show all it's details and only repeated tries give you any sort of improvement. It is difficult because of the huge dynamic range. It is only many images done by many imagers that give any where near the full picture to the rest of us.
That's a very nice image Marc ... ain't the wind a pain this year !
Thanks mate - glad you liked it.
Quote:
Originally Posted by avandonk
Very clear image of the faint HA in this region. I have literally spent years trying to image this object properly to show all it's details and only repeated tries give you any sort of improvement. It is difficult because of the huge dynamic range. It is only many images done by many imagers that give any where near the full picture to the rest of us.
Nicely done.
Bert
Thanks Bert. Not wrong there. So much dynamic range. It's like M42. Hard to please everybody.
Quote:
Originally Posted by RB
Wow Marc that is stunning !!
Excellent detail and sharpness, it looks fabulous on my monitor.
Overall a great image Marc. A couple of points that may help.
There is evidence of oversharpening. Some stars look very harsh and the dim areas in the top right for example are rippled with sharpening artifacts.
If you have it with software you can get sharpish stars without the unsharp mask harshness by using deconvolution. Again its trial and error but you don't want to push it too hard. You can also lasso dim areas and use gaussian blur or use the blur tool and rub over the affected areas to smooth them out. If you want to make stars smaller you can select out the stars using colour range tool and then use a small amount of minimum filter. Again, in small doses.
I am personally not a fan of unsharp mask. Smart sharpen in Photoshop seems to do a better job. Often unsharp mask makes stars that may already be distracting from the main object even brighter and more distracting.
You also have some coma in your system. Are you using a coma corrector? Is it set to the correct distance? Correctors like flatteners are designed to operate at a fairly exact distance from the camera chip to the last metal edge of the corrector (metal back distance). This varies with different cameras and correctors.
Overall a great image Marc. A couple of points that may help.
There is evidence of oversharpening. Some stars look very harsh and the dim areas in the top right for example are rippled with sharpening artifacts.
If you have it with software you can get sharpish stars without the unsharp mask harshness by using deconvolution. Again its trial and error but you don't want to push it too hard. You can also lasso dim areas and use gaussian blur or use the blur tool and rub over the affected areas to smooth them out. If you want to make stars smaller you can select out the stars using colour range tool and then use a small amount of minimum filter. Again, in small doses.
I am personally not a fan of unsharp mask. Smart sharpen in Photoshop seems to do a better job. Often unsharp mask makes stars that may already be distracting from the main object even brighter and more distracting.
You also have some coma in your system. Are you using a coma corrector? Is it set to the correct distance? Correctors like flatteners are designed to operate at a fairly exact distance from the camera chip to the last metal edge of the corrector (metal back distance). This varies with different cameras and correctors.
Nice image with lots of detail.
Greg.
Thanks Greg. yeah I might have got a bit heavy on the contrast but I didn't sharpen anything though. I used the shadow highlight tool to tweak the contrast a bit. I used one run of noise reduction. Ha pics always come very sharp. I know about the coma. I can live with it. I think my MPCC is off by 2-3mm but I can't do much about it. Unless I can find an adjustable/telescopic spacer with a lock nut? Like an helicoidal focuser system. You wouldn't happen to have something like that in your bag of tricks by any chance would you?
Marc, I use a Dell 24" UltraSharp 2408.
These are excellent monitors with a very wide gamut and very sharp detail.
The only problem is that sometimes I end up processing my images to what looks good on the monitor but when I check the image on my laptop the colours are not as good.
Looks awesome... Did a great job on the outer nebulosity!! Full size shot is magnificent.
Alex.
Thanks mate.
Quote:
Originally Posted by RB
Marc, I use a Dell 24" UltraSharp 2408.
These are excellent monitors with a very wide gamut and very sharp detail.
The only problem is that sometimes I end up processing my images to what looks good on the monitor but when I check the image on my laptop the colours are not as good.
Yeah I know what you mean. I've got 2 x 19" LCDs and the pics do look a bit different depending on the angle I look at them. Sometime I look at my pics on other monitors or TV screens and go "Argh! Did I do that?" . So it's always nice to get good feedback like yours.
Cool - I've got myself a 46" SONY Bravia a couple of weeks ago. The 100MHZ motion flow one. Got my PS3 plugged into it and I can download my pics and view them, pan and zoom with the PS3 controls. Pretty cool stuff. That's when I'm not playing motorstorm
Quote:
Originally Posted by Bassnut
Top work Marc, nice one, lots of detail, but Greg speaks wisely, spend some more time with deconvolute and processing generally.
Thanks Fred. I can't really deconvolve at that image scale. It's undersampled and I get ringing real quick. I'll have to go to much longer FL to up my resolution to use deconvolution in CCD Stack.
Trying another couple of shots now of the same through the ED80. I'll be gentle on the processing this time
Nice... Yeah mine was bought as a computer monitor.. Love to play games on it, but for displaying digital photos its incredible... I've watched TV on it maybe twice..
After taking on board a few comments re:processing from Fred and Greg I took 3 hours last night of Eta, so far more data. Didn't need to stretch as much. I also applied a slight deconvolution in CCD Stack.
The ED80 can take this in one shot. The FOV is similar to the 2 panel mosaic and the image scale pretty close. See the result below. I still like the first version too.
There are already awesome detailed crops of the area in these forums. 
. So it's always nice to get good feedback like yours. 
