Re: How Do I Get a TMB 175?
- Hi Bill
I mainly do astrophotogrpahy with my 175 which is mounted on a
Paramount ME. I use the Optec .62 FR which takes me down to f/5 which
is good and fast for a refractor and flat to the corners for the
smaller ccd I use which is the Starlight Xpress SXV-H9.
I am currently upgrading the camera which necessitates me getting the
I have had a number of my images on our Canadian Astronomy magazine's
web site as POW and a mosaic I did of the moon at f/8 was used this
month as the center spread on the magazine.
For imaging, the scope is simply beyond approach. I do LRGB imaging of
Ha regions from the city and they come out looking like narrowband.
Example: M16 http://tpo.ca/M16-2006.htm
or M1: http://tpo.ca/M1-2006.htm
The high strehl of these scopes, rock solid imaging train, (I added a
3.5" to 2.7 AP adapter after the 3.5" Starlight focuser and attached
the Optec focuser and filter wheel behind that), ensures no alignment
I collimated the scope in the spring of this year and even though I go
back and check it periodically, it is right on. In fact, I have been
toying with the idea of getting ccdinspector to doubly check the scope
but feel I am to some degree, doubling up on what the collimation and
images are already telling me.
Last night I did 4 hours on NGC7331 in Luminance, (2 hours on each side
of the meridian), no mirror shift, no temperature issues even though
there was a 10 degree drop during the run, (I run FocusMax every half
hour or so), and with the large lens shield, I did not turn on the
heaters though it was close due to dew starting to form up when I shut
down for the night.
The TMB 175 will handle the 6303 chip without a field flattener,
anything larger and the field flattener is needed and it's around $750.
My only regret is that I image from my backyard observatory and as I am
located in the suburbs of Toronto, Canada, my skies are around Mag 3.2
or another way of saying that for VLM, (visual limiting magnitude) of
around 3, (I can visually, only see three stars of the little dipper
and that includes Polaris).
The TMB 175, f/8 has made imaging in the city for me, a highly
Hope this helps.
All the best
--- In email@example.com, "William Ingalsbe" <ingalsbe@...>
> Dan: Do you know if there is a focal reducer available for the TMB
> plan to use the scope for astrophotography of deep-sky objects, aswell as
> the planets. Regards, Bill
- The threads are the same as a Tak 1 1/4" compression eyepiece holder
if you took off the outer tightening ring.
--- In firstname.lastname@example.org, "dennis" <tracy_tracy@...> wrote:
> I have a nice lathe and would like to make my own. I hoped you
> thread size.
> ----- Original Message -----
> From: mrgrytt
> To: email@example.com
> Sent: Sunday, September 10, 2006 10:42 PM
> Subject: [tmboptical] Re: How Do I Get a TMB 175?
> --- In firstname.lastname@example.org, "dennis" <tracy_tracy@> wrote:
> > Would you know the thread size of this adapter???
> No idea on the actual thread size. I took my Takahashi
> collimation scope to the shop so he could properly match the
> when making the adapters. The adapters were made on a CNC lathe.
> Since he has the setup saved he can surely make more of them, or
> there may be more in stock now.
> [Non-text portions of this message have been removed]