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Posts Made By: DJ Hanson

January 18, 2005 06:10 AM Forum: CCD Imaging and Processing/Solar System

Nice Nikon D70 Shots...

Posted By DJ Hanson

...some incredible D70 shots by others. Take a look:

http://tinyurl.com/6kfwg - Horsehead Nebula
http://tinyurl.com/3zxhj - M31 Andromeda Galaxy
http://tinyurl.com/422po - California Nebula
http://tinyurl.com/49tey - Comet Machholz & M45
http://tinyurl.com/7xmbh - Flaming Star Nebula
http://tinyurl.com/43utn - Running Dog Nebula
http://tinyurl.com/5okeq - M45 Pleiades
http://tinyurl.com/6jpby - M42 Orion Nebula
http://tinyurl.com/6whoa - N American Nebula
http://tinyurl.com/6qgct - Milky Way
http://tinyurl.com/67bgh - M20 Trifid Nebula
http://tinyurl.com/6qvec - Full Moon
http://tinyurl.com/6pyeb - Half Moon
http://tinyurl.com/52jjc - Lunar Eclipse
http://tinyurl.com/5j7o2 - Earth & Grand Canyon

Best,

--DJ

May 15, 2005 12:41 AM Forum: Film Astrophotography - Imaging and Processing

Rho Ophiuchus

Posted By DJ Hanson

Set my Nikon F towards Rho Ophiuchus 2 weeks ago, this was the 1st
image I've captured with my AIS Nikkor 135mm f/2. Captured using Kodak Elite Chrome 200, 15 min exposure, tracked on a Losmandy G-11. Rho Ophiuchus is one of my favorite objects with its variety of colors.

Best,

--DJ

April 7, 2004 01:54 AM Forum: CCD Imaging and Processing/Solar System

SCT Image Quality: Maybe a little OT

Posted By DJ Hanson

Hi John,

Visually, images of Saturn and Jupiter are quite stunning in my C11 (and it's old, 22 years old), given good seeing conditions first and foremost. This topic intrigues me too, the best resource I found is an article written by Thierry Legault. He summarized the effects of a central obstruction very nicely, showing potential effects on planetary imaging:

http://www.astrosurf.com/legault/obstruction.html

Still, looking at some of Damain Peach's C11 and LX200 Saturn's (as well as some others on this board) really make me think the SCT central obstruction issue is a non-issue in terms of planetary imaging:

http://www.theplanets.cjb.net/

Clear Skies,

--DJ

April 8, 2004 12:30 AM Forum: CCD Imaging and Processing/Solar System

Newby next shot

Posted By DJ Hanson

Hi Richard,

The differences from your 1st image to your latest, look primarily like differences in poor to good seeing to me. But if you can get some decent shots like your last ones, perhaps try stacking 500-1500 frames and applying Registax's wavelets 4-6, weighting more heavily on wavelets 5 and 6. The wavelets will help to bring out the cloud details greatly (but like any good thing, it can also be over-done)

Clear skies,

--DJ

April 10, 2004 02:42 AM Forum: CCD Imaging and Processing/Solar System

Webcam or Canon D10

Posted By DJ Hanson

Hi Robert,

I pretty-much echo Ryan and Russ's comments. I've compared a lot of planetary photos between both digital SLR's and webcams. IMO the webcam is better, multiple stacking to increase S/N ratio and the fact that one can remove instantaneous bad seeing which often occurs at less than 0.1 sec intervals (or at least can). Seeing is probably the biggest factor to good, crisp imaging. On the downside is the need for a computer, you could try connecting to a PC if you have one available in your backyard, etc. That nice 14.5" dob of yours would yield some nice planets with a ToUcam 840 (provided good seeing of course)! I spent $45 for my ToUcam 740 on eBay (no bad pixels either), but got lucky. Most 840's are going for $150 or so.

But the digital SLR's are getting really nice and I see a growing trend. I've seen some pretty impressive DSO imaging lately using them...

--DJ

April 27, 2004 01:36 AM Forum: CCD Imaging and Processing/Solar System

Finally tried a Toucam

Posted By DJ Hanson

Hi Tom,

Nice images. I too use a C11+ToUcam 740 combo for planetary imaging. I often image at f/30 with a Televue 3X. I think the best part of the webcam is its ability to weed out bad frames (due to changing seeing, etc) and the ability to stack so many frames (to increase s/n ratio). Have funsmile

--DJ

May 4, 2004 02:43 AM Forum: Film Astrophotography - Imaging and Processing

Time exposure on fixed tripod

Posted By DJ Hanson

Hi Joe,

The table at the bottom of the following URL states maximum times until star trailing for different lenses, 17-300mm, assuming a latitude of 45 degrees ("T (sec)"):

http://origins.colorado.edu/~rachford/widefield/calc.html

--DJ

May 20, 2004 12:48 AM Forum: Film Astrophotography - Imaging and Processing

Comet Neat

Posted By DJ Hanson

Hi Paul,

Nice beginning shot. I've seen different methods...many seem to track the comet if they're imaging a smaller FOV like yours, which I think makes sense as the movement of the comet may be more detectable in the image. I personally like larger FOV comet shots, taken with fast telephotos (say f/3.5 and faster) and in this case I track the stars (but in most cases do not even manually guide, although this should be even better). I've attached a 4 minute shot and as you can see I've got some beginning trails as I only did rough polar alignment with tracking. I simply attached my Nikon F/Nikkor to an EQ-1 mount, turned on the RA motor and did very rough polar alignment using the SLR...this was the quickest/convenient method for me with my limited amount of equipment and limited time to capture the comet prior to sunrise.

Best,

--DJ

October 27, 2004 04:17 AM Forum: CCD Imaging and Processing/Solar System

Where to buy ToUCam (mac or pc)?

Posted By DJ Hanson

Hi Tom,

The only difference between the 740 and 840 is the casing and sometimes price. Same CCD...

For the ToUcam 840 you can look at pocketscope.com or astrovid.com. You can get the discontinued 740 on eBay and astromart.com... I bought my 740 on eBay for $45, but got very lucky with this price. Most are probably $100 to $150. If you get a webcam, check it out for any severe "hot pixels". There are usually always a couple minor hot pixels on each CCD chip, which are not a problem, but my first 740 actually had a large blue cluster of bad pixels and I ended up exchanging it at pocketscope.com (no problems).

Best,

--DJ

November 20, 2004 06:29 AM Forum: CCD Imaging and Processing/Solar System

Nice D70 Shots...

Posted By DJ Hanson

...and some more nice D70 shots with an IR mod:

http://www.pbase.com/terrylovejoy/erwins_modded_d70_gallery

...also, check out Terry's 300D shots with an IR mod:

http://www.pbase.com/terrylovejoy/tak_e160

Had to double-check that those weren't "SBIG" captions! Wonderful stuffsmile

--DJ