Merlin66

If required, only for visual.... The CCD/CMOS cameras are not sensitive beyond 1100nm, in the NIR.

https://www.ccdware.com/resources/ The calculator allows you to assess where the dust motes are sitting.......

You're certainly trying very hard to accommodate the linear CCD array. I respect your decision and hope you find a workable solution. With "conventional" sensors used in the SHG, life is easier - the processing software can correct for tilt/ slant/ smile......

I think this needs to be made a "sticky" The Canon DSLR filters: There are two built into the camera body: One, #2 filter, (blue tinted close to the chip) is a colour correction filter which suppresses the red response, to give a "better" colour balance. The other, #1 filter, is at the front and acts as a UV-IR cut filter as well as an "anti-alias" dust shake element. The "normal" Mod is to remove #2 filter to enhance the response to Ha wavelengths. A FULL spectral mod involves removing both filters to provide access across the UV to the NIR. (I use this type of mod for spectroscopy)

This seems at odds with: Applicants are required to be a member of an affiliated organization, such as an astronomy club that belongs to the Astronomical League;

The AAS seems to be restricted to US members? Many amateurs already submit data to various ProAm spectroscopic campaigns. Their work is recognized by the professionals.

Here in Australia we can get some intense sunshine - followed by drought, fire and torrential rain. Luckily not all on the one day!

The original PST had the ERF coating on the objective -a "gold" look. This failed pretty quickly, and was replaced under warranty by the "Blue" objective and an internal ITF at the eyepiece holder. I haven't seen any of the old "gold" objective PST for a while.

+1 for the Baader solar film.

I’m surprised you found a concern with IR transmission. The Baader solar film has been around for many years with no reported issues. I do recommend a Continuum or similar filter for improved contrast.

Very nice, well done! Always appreciate multi wavelength images.

The mating thread to the eyepiece may be odd ball and depend on the eyepiece.

That’s an interesting comment. I’ve been using 200 -400 ISO as a base for the Canon 450D when doing spectroscopy. Why do you thing 800-1600 is more appropriate???

They are both capable of doing the job, and seem to be far more robust than the original.

Paul, The USB3 camera will still work under USB2 albeit at a reduced frame transfer rate. I use many ZWO cameras (mostly for spectroscopy and solar ) and use FireCapture to control the camera and image acquisition, then AutoStakkert 3 for stacking followed by ImPPG for the tweaking..... Hope that helps.

Just to add some info: The etalon and the final blocking/ sort filter are very robust and usually do not give any problems. Unfortunately the Induced transmission filter (ITF) element in both the Coronado and Lunt solar scopes is prone to premature failure. As mentioned, 3rd party alternatives are now available from Beloptik and Maier.

Spier24, My comment was Re the spreading of the grease on the baffle of SCT's etc.

Richard, There's no mention of a UV/IR filter being required on the 60mm DayStar Scout. https://www.daystarfilters.com/Scout/60ScoutDS.shtml For those without PS you can colour a mono image in Irfanview or any other image/paint package by clicking "Colour correction" and changing the RGB numbers to suit. I've used R84 G-14 B-114 for Ha and R75 G38 B22 for CaK.

Just noticed Chris beat me to this suggestion!

In scope designs where the main mirror moves on a baffle tube (ie SCT, Mak etc) the flop/slop can be minimised by running the focus through full travel in/ out a few times. (about 30 turns of the knob in a SCT). This re-spreads the grease between the baffle and the mirror slider and reduces the clearances and hence the slop. Should be done regularly.

Robin, You’re results are an inspiration to all amateur working in spectroscopy. well done!

Welcome to the bright side! The PST is an ideal instrument for the novice. Easy to handle. easy to use. There's a couple of decent sized sunspots currently visible: https://www.spaceweatherlive.com/en/solar-activity.html ( there are two non- Meade suppliers of replacement ITF filters - Beloptic and Maier Photonics. Both are very good)

Back in the 60’s I used a 6” f8 and the only eyepiece I had was a solid brass 1/2 “ Ramsden. I’d love to find one to relive those days.

It’s a 2” x 24 tpi “SCT” thread.

The ES x3 tele-extender is a reasonable option, it’s very close to being a telecentric, like the TV powermates. I use one on the SM60/ ED80 for solar observing when the seeing is good.