John

Thanks Andrew - I have the 12 inch dob out at the moment so I'll take a look

I'm the same now Steve. I used to put up with tiny eye lenses and very short eye relief but I prefer some comfort these days.

They are planning on increasing them to 12,000 in number and possibly even going as far as 42,000.

Starlink - the plan is to launch 12,000 of them eventually possibly extending to 42,000 .....

The target is 12,000 in total with a possible extension to 42,000 ! The Earth now has a ring.....

Just been watching them passing beneath Leo. Dozens of the things and brighter than I was expecting as well.

c2020 F8 Swan is in Sculptor at the moment at magnitude 7.8 according to "The Sky Live": https://theskylive.com/c2020f8-info

Try and find the constellation of Cancer - it is between Gemini and Leo. There is a lovely star cluster called "The Beehive Cluster" in Cancer which should look nice at low magnification with your scope. Also, in Gemini there is another great star cluster called Messier 35 (M35). Another nice sight in the small scopes at low power. Cancer: Gemini:

This is what I use for my 12 inch F/5.3 dobsonian: I have tried laser collimators including the Baader and Hotech ones but the above has consistently worked and the scope star tests well after its been used so I'm happy with it

Thats odd. One of those two rails should have threaded holes though it. I seem to recall that the screws should go through the rail with the unthreaded holes and screw into the holes on the other rail thus forming a clamp

Don't they work like a clamp, with one side having threaded and the other with unthreaded holes ?

There is a mix of sizes, brands and cost in my cases now:

Which screws James ? Can you post a picture ?

Nothing wrong with any of those

It sure is. The original Revelation 8 used to be £199 new from Telescope House. The lowest cost 8 inch dob at that time, and since I would think.

Do we know what company produces these scopes for Bresser John ? Skywatcher are obviously made by Synta and Meade used GSO for their Lightbridge dobs. GSO also produced the Revelation and TS dobsonians as well. I was just wondering about these Bresser dobs ?

I had the 4.8 Nagler T1 as well at one point. That and the 7mm were my first Naglers. Eye relief was not a strong point I agree. The 4.8mm was very sharp though. Apparently Roland Christen used the 4.8 T1 Nagler as his principle testing eyepiece for his refractors for many years. I didn't hate mine at all but I was happy to move to the T6 Nagler 5mm and 7mm to replace it in due course because they proved to be better eyepieces Then the Pentax XW's and Ethos's proved to be even better .... for me at least

Nice scope - I used to have an earlier version of the Revelation 8. My first dobsonian ! Yours is better turned out than mine was though

Actually, the 100 degree eyepieces that I have used have been well corrected even at F/5. Look at the prices of such eyepieces though . With such eyepieces another aberration called coma becomes more obvious but that is produced by the primary mirror of the scope, not the eyepiece. Astigmatism (eyepiece produced) looks like this: Coma (scope mirror produced) looks like this: You can have a combination of both of course !

These were the sharpest eyepieces that I've used - a University Optics HD ortho 5mm and a TMB Supermonocentric 5mm. The latter is probably the best high power eyepiece that I have ever owned in terms of sharpness, contrast and lack of light scatter. With a 30 degree AFoV and about 2.8mm of eye relief it was hard work though. Vixen have done very well to produce their HR range that deliver excellent performance and provide 10mm of eye relief.

From my experience, eyepieces optics start to be challenged (ie: show aberrations if they have them) from around F/7 and faster. From F/5 things can get really messy in the outer parts of the field of view if the eyepiece is not well corrected.

I have not used one myself but it sounds like something an observing tent might be the sort of thing you are after ?: https://www.astroshop.eu/instruments/omegon-tent-observatory/p,12278

No. The eyepiece will show more sky (a larger true field of view) with the F/6 scope. If it is a low cost eyepiece then there may well be some distortion of star images towards the edges of the field of view at F/6 though.

I'm not sure that you actually have any gaps. Moving from 12mm to 8mm is quite a natural progression as is 20mm to 15mm. I think you have all the eyepieces you need to make the most of your scope If you can start to put some £'s aside towards ultimately moving to, say, a 200mm aperture scope, that will make far more difference than investing in more eyepieces I reckon.

The true field of view is derived, roughly, from the apparent field of the eyepiece divided by the magnification that the eyepiece gives in the scope. If you want a larger magnification and still to retain the same true field of view, you can use an eyepiece with a larger apparent field and a shorter focal length. This online tool can be played around with to find what different combinations of scope and eyepiece can show in terms of field of view: https://astronomy.tools/calculators/field_of_view/ M81 and M82 are some of the targets available in the above tool.