Wide-Fields and Star Trails - my latest astrophoto site update (Hasselblad)

Friends,

 

I've finally got around to putting an update of my web site together. It's mostly wide-field

and star trails images taken with my Hasselblads often piggy-backed on my 8" classic

Meade LX200 telescope. Focal lengths used range from 30mm thru 500mm.

 

The link to the newest (49) images is

 

http://homepage.mac.com/tarashnat/astrophoto/new.html

 

and the home page of the site is at

 

http://homepage.mac.com/tarashnat/astrophoto/welcome.html .

 

Feel free to comment and/or to ask questions.

 

Enjoy!

 

Taras

Taras,

 

Nice shots! Can you tell us what equipment you used (Hasselblad gears that is!) and whom make the piggy back adapter for you.

 

We have a Meade LX50, is that too small for astrophotography use? Biggest focal length of my Hasselblad lens is the 180mm.

 

Evan

Evan,

 

For most of my photos, I used a 500C/M or 503CW, though occassionally a 2000FCW and

a SWC/M. Most of that information is on the individual pages below the image(s). Where I

remembered to record the data I include the body, the lens, the exposure, the aperture,

and whether the exposure was guided/tracking the sky, or stationary tripod mount.

 

An LX50 uses the same optics as an LX200, so I think it should be able to handle the

weight of a Hasselblad. I use a Meade standard wedge and a Losmandy dovetail system to

mount the camera above and counterweights below the tube. I use a Losmandy DCM-1

mount for most of the shorter lenses, to avoid having the dew sheild in the photo, and a

DCM mount for the longer lenses. The DCM-1 allows to change the altitude the camera is

pointed to relative to the optics of the scope. The fork of the LX50 is not as thick as the

LX200, but it was being used for astrophotography before the LX200. It just requires more

patience and attention to guiding.

 

Taras

By optics, I mean optical tube. My LX200 actually has LX50 stencilled on the tube...

 

Taras

Beautiful work!

 

Kerkko K.

Nice work. I especially like the shot of Scorpius and Sagittarius hugging the southern horizon. They sit up higher from where I see them.

Outstanding images! An inspiration to try some of this work myself. I find it interesting how you use such a wide range of lenses to capture the night sky.

<i> Outstanding images! An inspiration to try some of this work myself. I find it

interesting how you use such a wide range of lenses to capture the night sky.

</i><br><br>

Thanks. One of the main reasons I use so many lenses is to try to use the full area of the

transparency (if I ever choose to project it), and that without having the budget of NASA, I

can't get my Hasselblad that much closer to the moon or other celestial targets. My feet

are still the most important accessory, but only to get me to a point where there is just

less enough light pollution to get decent exposures of the subjects I shoot.

<br><br>Taras

Hi Taras

 

Thanks for that - great pictures. They've reminded me that I've always wanted to have a bash at star-trail photography, and inspired me to have a go. I know next to nothing about astronomy, but have come across some lessons on how to identify the 'common' constellations. I've seen photos before where the camera is pointed on The North Star (or Polaris as I've just learnt!), and the star trails form complete concentric circles around this star. However, I've just read that the stars move around Polaris anti-clockwise at the rate of 15degrees per hour, so they must take 24hours to travel a complete circle. Are those 'complete circle' shots a figment of my imagination, or do they just appear to be complete circles whereas they're 'joined-up' arcs scribed by various stars that 'join up'? Is that question as clear as a foggy night? I think that I'm asking - how long an exposure would I need to make in order to get the effect I'm looking for? I will experiment, but I just thought I'd ask as well!

 

David

David,

 

It all depends from where and during which season the photo is taken. I guess someone

above the Arctic (or below the Antarctic) circle close to the winter solstice can get a 24 hour

exposure. But baring that, depending on the distribution of the brighter trails, it may look at

first glance like complete circles, but on closer examination one can see the starts and ends

of the trails. Also, silhouettes of buildings/trees can help with the illusion of complete circles.

 

Taras

Thanks Taras

 

I've found a photo in a book, and I see now that the circles aren't completed by individual stars, although at first glance they appear to be. I think I'll try for a six hour exposure which should give me 90degree arcs. I live in the north of Scotland in the UK, so it's probably dark for around sixteen hours a day in winter. Typically, it's been raining for the last couple of nights, with not a star in sight, so I haven't even been able to try out my new-found skill of identifying Polaris!

Taras,

 

Very fine work. Nice to see. Thanks for sharing it.

 

Charles

David,

 

One thing you need to be mindful of with these long exposures is the onset of dew. I

usually have a dew heater wrapped around the lens to keep it warmer then the dew point.

 

Taras

Thank you for sharing!

Thanks Taras. Er, what is a dew heater? I still haven't seen a clear sky - the last couple of nights have been foggy, and last night there was a freezing fog. I had thought that I might need something to eliminate condensation, both on the lens and on the film, but the best idea I could come up with was a wee electric blower (and then there might be other dangers!) I'll be using a Hasselblad SWC/M for my first attempts -it's the only camera I have aside from the 5x4" and 10x8". Perhaps you could recommend a 'dew heater' for this camera. Also, I see that you tend to use fairly fast film with the lens wide open. I've just loaded a roll of Velvia 50 into the camera. Would you say that's too slow?