Peter Drew

It depends on what is currently available to be seen in "white light". Given the opportunity, you should be able to see sunspots, faculae which look like slightly lighter granular patches usually towards the limb. Genuine solar granulation can be seen during excellent seeing although 10" aperture, assuming a full aperture filter, might just be overkill due to daytime seeing conditions. 🙂

I'm mainly a solar observer these "days" so can't currently comment on light pollution. However, I do believe the air quality and hence the transparency has improved. I have a 5 finger test for solar air quality. It is based on how many fingers on an outstretched hand are needed to occult the Sun's disc plus the surrounding scatter. Recently there have been many 1 finger days. 🙂

Poor Helen, perhaps better known for her dropping the Olympic torch. 🙂

Sounds rather odd. If you can focus with just the eyepieces you should be able to focus with the Barlow. Usually, a Barlow will bring the focus point out which seems to be the opposite of your problem. 🤔

The star diagonal will give you an erect image but laterally reversed. My experience with erecting prisms is that those with 90 degree angle seem to work best. 🙂

I've worked on a couple of AP 6" "Super Planetary" refractors. I shortened the one owned by the late Douglas Arnold so that he could use binoviewers on it and folded one for another owner so that it would fit into his small observatory. The only AP refractor I've actually looked through was an early version 92mm Stowaway, someone, can't remember who, loaned me one for a day at Kelling. I have to say that terrestrially it was amazing, regardless of magnification it still gave a perfect image. Sadly it was cloudy at night and I didn't get the chance to use it at night. Would I wait years for one? NO. 🙂

There is a caveat with this otherwise sound advice. I's true that working on Ha is a monochromatic wavelength so no need for an apochromatic class telescope. However, chromatic aberration isn't the only limitation of inexpensive refractors, spherical aberration and so-so figuring also conspire to provide less than perfect images. So if contemplating an achromat, make sure it's a good one. 🙂

On paper, the StellaMira 85 would be a good choice as the fr 6.6 coupled with the Quark's 4.2x Barlow gives the optimum overall focal ratio for the Quark system. 🙂

I use the same method, a 1mm stainless steel strip running on stainless steel rollers that are themselves in bearings. The free movement is controlled by an adjustable PTFE pad. 🙂

Narrowing the band width does reduce the brightness which is one of the reasons why imagers prefer the system as the enhanced surface details can be brightened by exposure and processing. Visually, double stacking dimness can be offset by placing an opaque covering over your head. If the PST is preowned it will be worth checking the ITF, the filter just before the blocking filter as theses deteriorate over time and also reduce the brightness of the image. Finally, using a Ha telescope and more so a double stacked version is quite a steep learning curve with many nuances to deal with. The usual advice is to tune the single stack to provide the best view and then to tune the double stack unit until the brightness is best. Further refinement can be made by "clocking", rotating the double stack unit relative to the rest of the telescope. 🙂

Whatever you do to try and release it, don't subject it to mechanical shock. This could detach the etalon plates which are only kept together by molecular bonding. 😱

I did the opposite out of sentimentality. Despite already having 5 "modern" SCT's I bought a 1980's orange C8 simply because I had always wanted one! 🙂

The azimuth bearing system should work fine, I use a similar approach on my 30" Dobsonian. 🙂

I think that the corrector, being a correcting rather than image forming component works in its favour as it doesn't have a focus. 🙂

I actually met and shook hands with the gentleman who made the UK Schmidt camera corrector. Sadly nothing rubbed off! 😆

The main potential cause of chromatic effects in Maksutovs and Schmidt-Cassegrain telescopes is mechanical "wedge" across the optical diameter of the corrector elements. If the wedge is severe, the component operates as an objective prism and introduces false colour.

I have been a Ha solar observer for over 20 years. I began with a Coronado Helios1 70mm telescope, bought used for £2000, it was the one originally used for Coronado's publicity photos. When the PST arrived on the scene I was amazed to find that a good one gave very similar performance at the then price of £499. I purchased a used one and subsequently another to make a PST binoscope which gave wonderful results. The cost of larger apertures then, as now, gave me no option but to make my own so I joined the early pioneers of PST modding and have made more than 20 in the 100 mm- 150 mm range. My current PST (Peter's Solar Telescope) is a 150mm F10 optimised for high resolution, high magnification binoviewing. I have no interest in imaging or full disc viewing, I have a 60mm for the latter if needed. I have no extra input to the X versus Y "debate", I have seen excellent and disappointing versions of all makes. 🙂

I think the largest currently available external etalons are Solarscope 100mm, lunt 100mm and Coronado 90mm. 🙂

They appear to be early craters that have been inundated by lava at some stage leaving just the tops of the crater rims showing, Nearby classic craters occurred later than that event. 🙂

Bespoke Ha solar telescopes such as those of Lunt, Coronado and Daystar are inherently safe. Each contains several specialised components, if either one or all fails then the telescope just doesn't work. White light solar observing does have a degree of potential danger. Usual safeguard is to use a front mounted filter or a rear mounted Herschell wedge, both of these are safe in good condition and used properly but both rely on effectively one layer of protection. Public involvement solar observing requires close supervision at all times by competent experienced observers. 🙂

Perfectly understandable, particularly in this day and age. Best solution would be to try and get a friend to accompany you. Good luck! 🙂

A Lunt solar telescope is a pretty safe buy, good customer support. Double stacking will enhance the photographic aspect, a double stack 60mm would probably give you more satisfaction than a single stack 80, still pricey though. As far as life span is concerned, etalons last well as long as you don't drop them, blocking filters are also good long term. The Lunt ITF, (and other makes), are known to fail prematurely, the Lunt units are usually replaced FOC either by Lunt or the original vendor. I've always bought solar gear used but with a good track record. 😆

I was referring to a 8" and 12" that I made. 🙂

An interesting design, the Schmidt-Newtonian, a bit of a "Cinderella" instrument. I made, possibly the earliest SN in the early 1970's, I had been making some 8" F20 Schmidt-Cassegrains with optics by James Muirden and Jim thought it worth trying a Schmidt-Newtonian. We made a 4.25" F4 and gave/sold (?) it to noted UK amateur Colin Henshaw who used it mainly overseas. I seem to remember an 8" and 12" version. 🙂

Same here. Brilliant cloudless sunny day. Having already seen the promising solar image on GONG I fired up my main solar telescope for the first time in ages and had a look. Seeing somewhat unsteady but a good assortment of proms, plages and filaments. 😀