Call to all Coronado SMII users....

[Merlin66 (Ken)]

I'm trying to gather information on the effectiveness of the Coronado SolarMaxII Rich View tuning arrangement.
I have repaired a few and found the Rich View tuning not working as advertised.
I would be interested to hear your first hand feedback on these solar filters.
Help me to help future prospective buyers......

[GUS.K (Ivan)]

Hi Ken,I've owned three SM60 richview etalons and two SM40's over the last few years and found a lot of variability in the use of the richview tuner. One of the 60's produced excellent contrast with minimum tilt of the T max in SS, and turning the RV tuner would show different detail. The other two 60's were poor performers in SS, but worked great as DS units on my Lunt LS60 scope. I adjusted the pin into different slots hoping the SS view would get better, with one starting to show detail at the full screwed in position, with the pin bearing so tight on the etalon, that it took a little effort to back it off, and the other one would show no detail at all in SS. The two SM40's worked fine. I have also owned an SM40 non RV etalon and comparing to the 40mm RV etalons, the amount of detail was similar. I now own a Lunt 60mm DS etalon.

Ivan.

[John W (John Wilkinson)]

Hi Ken,
I owned a SMII60 mm scope and had no trouble with the tuning - When i got it I had to shift the lever a couple of slots but once set it was good. If fact I found the tilt tuning easier than using the pressure tuner on my Lunt 100.
Regards,
John W

[Merlin66 (Ken)]

Thanks for the feedback.....
I'm about to measure the bandwidth and effect of the tilt angle (in CWL movement) with my SM 60 etalon.
Are there any SMII users in/ around Geelong who would be prepared to allow me to test their filter for comparison.
Any other feedback/ comments?

[Merlin66 (Ken)]

I just reminded myself (!!) that an identical study of the SM60 tilt etalon was conducted back in 2008 by Aristidis Voulgaris.....
He found the FWHM bandpass was 0.64A (0.68A as measured in the Ha line) and the tilt 0-1.3 degrees moved the CWL from +0.46A (red wing) to -1.2A (blue wing) (based on the Ha line)
This allows a doppler shift imaging from +21 to -55 Km/s
His full paper (pdf) is 572Kb - to large to upload here, but drop me an email for a copy.

It would be good to do a comparison with the Rich View SMII etalon.....