truss dob- astrophotography?

[BIG BEN]

would a 16 inch truss dob make a good scope for astrophotography

[seeker372011 (Narayan)]

No, it would be a nightmare and results will be rubbish

[Zuts]

Hi,

You may be able to take some planetary and moon photos.
Tracking would be impossible on an eq mount as it would flex too much and there is really nowhere to mount it so DSO is probably not on. Even on an eq platform it may still flex to much.

I am assuming it is a normal truss tube and not some super expensive super rigid one.

Paul

[iceman (Mike)]

If you can get an EQ platform big enough (I assume someone like roundtableplatforms could make them that big), then yes - you could use a webcam with an EQ platform to do planetary and lunar imaging.

But without tracking, it would be very frustrating.

[Orion]

Originally Posted by seeker372011

No, it would be a nightmare and results will be rubbish

Some of the imaging that has been done with large aperture alt/az telescopes have been great, this is an example from the Obsession Telescope imaging section.http://www.obsessiontelescopes.com/imaging/index.html

[gary]

Originally Posted by BIG BEN

would a 16 inch truss dob make a good scope for astrophotography

Whilst it may not be the best choice, as Ed kindly mentions, some users
have achieved stunning results using truss pole Dobs, including of
deep sky objects.

You might want to have a look at my responses on some earlier threads -
http://www.iceinspace.com.au/forum/s...ad.php?t=23184
http://www.iceinspace.com.au/forum/s...ad.php?t=11729

In a nutshell, you can use the scope undriven for short exposure
photographs of the Moon and planets. Alternatively, by driving the scope,
either on an equatorial platform or in Alt/Az mode through a drive system
such as the ServoCAT, users are routinely capturing deep sky objects as well.
The posts I cited above discuss the issues of field rotation which should
be considered when driving in Alt/Az mode.

Don't consider placing the OTA onto an equatorial mount such as
a German Equatorial. At best, place it on a platform.

Don't forget that one of the most important attributes of a scope for
astrophotography is its focal ratio (f/number), that is the focal length divided
by its aperture. This focal ratio determines the "speed" of the optical system.
The smaller the f/number, the faster the optical system and the less
exposure time required. In this regard, most truss pole reflectors have
small f/numbers and are optically fast, thus allowing for short exposure
times. Coupled with their large apertures, this then can provide high resolution
images.

These days, most of the world's large professional telescopes are engineered
to be Alt/Az driven and have small f/numbers combined with massive apertures
and all of these telescopes are used exclusively for digital imaging.

Best Regards

Gary