ASTRO: IC1795 test shot

this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that the
play of the camera/filter wheel nosepiece in the barrel of the Optec focuser
is the culprit

it uses jam screws to retain the camera. I have been thinking for some time
that I should just disassemble it and thread it on the lathe and then it
would always be straight. I could keep it in place with a big jamnut on it
to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....

My ST-7 only has such a nose piece and in the JMI focuser on my 6" f/4
it would rock. With the depth of field at f/4 being only a few microns
I never did get the entire field in focus. One side or the other always
had blobs for stars. Why manufacturers take that route at all I don't
understand. The Van Slyke stuff I now use screws together so no more
tilt problems unless the scope is out of collimation. When I first
starte with the 14" LX200R I used the Meade focuser which also rocked.
Even at f/10 I'd often see a corner tilted too much. It had to go.
Except for that it was a very good focuser (except for no temperature
compensation). If they'd thread it it would be far better for only a
few dollars more cost.

So why moving from 3nm to 4.5? I'd think with your skies narrower would
be better. Though this way I think I see more stars. Hard to tell with
the change in scopes as the scale is smaller here. F ratio about the
same however. What was the exposure time?

Rick


Richard Crisp wrote:

this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that the
play of the camera/filter wheel nosepiece in the barrel of the Optec focuser
is the culprit

it uses jam screws to retain the camera. I have been thinking for some time
that I should just disassemble it and thread it on the lathe and then it
would always be straight. I could keep it in place with a big jamnut on it
to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

it is a matter of moving from 6nm to 4.5nm

i sold the AstroDon 6nm emission line set and have replaced them with the
4.5nm set from Cust Sci, which I greatly prefer


"Rick Johnson" wrote in message
...
My ST-7 only has such a nose piece and in the JMI focuser on my 6" f/4 it
would rock. With the depth of field at f/4 being only a few microns I
never did get the entire field in focus. One side or the other always had
blobs for stars. Why manufacturers take that route at all I don't
understand. The Van Slyke stuff I now use screws together so no more tilt
problems unless the scope is out of collimation. When I first starte with
the 14" LX200R I used the Meade focuser which also rocked. Even at f/10
I'd often see a corner tilted too much. It had to go. Except for that it
was a very good focuser (except for no temperature compensation). If
they'd thread it it would be far better for only a few dollars more cost.

So why moving from 3nm to 4.5? I'd think with your skies narrower would
be better. Though this way I think I see more stars. Hard to tell with
the change in scopes as the scale is smaller here. F ratio about the same
however. What was the exposure time?

Rick


Richard Crisp wrote:

this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that
the play of the camera/filter wheel nosepiece in the barrel of the Optec
focuser is the culprit

it uses jam screws to retain the camera. I have been thinking for some
time that I should just disassemble it and thread it on the lathe and
then it would always be straight. I could keep it in place with a big
jamnut on it to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Do they even make the 3 any more? I didn't see it on their site.

Think I may have found the source of my flat problem. I've got to wait
for the sun to get lower to expose some flats to make sure. The center
screw appears to contract more than the plastic (teflon?) bushing and
binds. The wheel rotated fine until I got near the lum filter then it
got tight. I losened it an eighth of a turn and now it turns fine.
Each filter does have a registration mark so it would reregister for the
other filters where it turned smooth. I know when I put the filter
wheel back in a couple months ago it was turning fine. Just have to
allow for the cold. The rubber "O" ring was still plenty rubbery and
didn't appear the least bit slick, hard or dented at 10F.

Rick

Richard Crisp wrote:

it is a matter of moving from 6nm to 4.5nm

i sold the AstroDon 6nm emission line set and have replaced them with the
4.5nm set from Cust Sci, which I greatly prefer


"Rick Johnson" wrote in message
...

My ST-7 only has such a nose piece and in the JMI focuser on my 6" f/4 it
would rock. With the depth of field at f/4 being only a few microns I
never did get the entire field in focus. One side or the other always had
blobs for stars. Why manufacturers take that route at all I don't
understand. The Van Slyke stuff I now use screws together so no more tilt
problems unless the scope is out of collimation. When I first starte with
the 14" LX200R I used the Meade focuser which also rocked. Even at f/10
I'd often see a corner tilted too much. It had to go. Except for that it
was a very good focuser (except for no temperature compensation). If
they'd thread it it would be far better for only a few dollars more cost.

So why moving from 3nm to 4.5? I'd think with your skies narrower would
be better. Though this way I think I see more stars. Hard to tell with
the change in scopes as the scale is smaller here. F ratio about the same
however. What was the exposure time?

Rick


Richard Crisp wrote:


this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that
the play of the camera/filter wheel nosepiece in the barrel of the Optec
focuser is the culprit

it uses jam screws to retain the camera. I have been thinking for some
time that I should just disassemble it and thread it on the lathe and
then it would always be straight. I could keep it in place with a big
jamnut on it to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

they made one to order earlier this year. I think they actually live up to
the name "custom" in Custom Scientific.

hopefully your fix will be effective so you aren't shut down

good sleuthing!
rdc

"Rick Johnson" wrote in message
...
Do they even make the 3 any more? I didn't see it on their site.

Think I may have found the source of my flat problem. I've got to wait
for the sun to get lower to expose some flats to make sure. The center
screw appears to contract more than the plastic (teflon?) bushing and
binds. The wheel rotated fine until I got near the lum filter then it got
tight. I losened it an eighth of a turn and now it turns fine. Each
filter does have a registration mark so it would reregister for the other
filters where it turned smooth. I know when I put the filter wheel back
in a couple months ago it was turning fine. Just have to allow for the
cold. The rubber "O" ring was still plenty rubbery and didn't appear the
least bit slick, hard or dented at 10F.

Rick

Richard Crisp wrote:

it is a matter of moving from 6nm to 4.5nm

i sold the AstroDon 6nm emission line set and have replaced them with the
4.5nm set from Cust Sci, which I greatly prefer


"Rick Johnson" wrote in message
...

My ST-7 only has such a nose piece and in the JMI focuser on my 6" f/4 it
would rock. With the depth of field at f/4 being only a few microns I
never did get the entire field in focus. One side or the other always
had blobs for stars. Why manufacturers take that route at all I don't
understand. The Van Slyke stuff I now use screws together so no more
tilt problems unless the scope is out of collimation. When I first
starte with the 14" LX200R I used the Meade focuser which also rocked.
Even at f/10 I'd often see a corner tilted too much. It had to go.
Except for that it was a very good focuser (except for no temperature
compensation). If they'd thread it it would be far better for only a few
dollars more cost.

So why moving from 3nm to 4.5? I'd think with your skies narrower would
be better. Though this way I think I see more stars. Hard to tell with
the change in scopes as the scale is smaller here. F ratio about the
same however. What was the exposure time?

Rick


Richard Crisp wrote:


this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that
the play of the camera/filter wheel nosepiece in the barrel of the Optec
focuser is the culprit

it uses jam screws to retain the camera. I have been thinking for some
time that I should just disassemble it and thread it on the lathe and
then it would always be straight. I could keep it in place with a big
jamnut on it to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".





--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Richard,

nice test shot. I would even like it if it was the final version :-)
But you probably will want to do a few more hours on it.

Stefan

"Richard Crisp" schrieb im Newsbeitrag
t...
this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that
the play of the camera/filter wheel nosepiece in the barrel of the Optec
focuser is the culprit

it uses jam screws to retain the camera. I have been thinking for some
time that I should just disassemble it and thread it on the lathe and then
it would always be straight. I could keep it in place with a big jamnut on
it to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....

actually in my case I need to determine if I have tilt or if I need to use
my field flattener

I think I remember that I was able to use the 6303 without the flattener on
the AP155EDF but it has been since Aug of 2004 since I last used the scope
and that is a long time ago

now it is raining for a few days and looks to be cloudy for the next week
according to the forecasts.

but the satellite photos make me think I may get one night that may be clear
during the next few days.


"Stefan Lilge" wrote in message
...
Richard,

nice test shot. I would even like it if it was the final version :-)
But you probably will want to do a few more hours on it.

Stefan

"Richard Crisp" schrieb im Newsbeitrag
t...
this is first light for the Cust Sci 4.5nm Halpha filter and it has been
since Aug 14, 2004 that Ilast used the AP155EDF f/7 and Optec TCF-S

It looks like I may have a bit of tilt in the system and I suspect that
the play of the camera/filter wheel nosepiece in the barrel of the Optec
focuser is the culprit

it uses jam screws to retain the camera. I have been thinking for some
time that I should just disassemble it and thread it on the lathe and
then
it would always be straight. I could keep it in place with a big jamnut
on
it to push agains the filter wheel faceplate.

I guess I need to fire up the lathe tomorrow and make some chips....