Search found 29 matches

by AndiesHandyHandies
Sun Jul 01, 2018 5:47 pm
Forum: Solar Scope Modifications
Topic: Can i use my EDGEHD800 for Ha?
Replies: 10
Views: 848

Re: Can i use my EDGEHD800 for Ha?

Hi Mark posted a tip for not cutting a refractor to reach focus, of moving the PST collimator lens, or equivalent for telescope F No, from the PST up the focuser tube. I decided to try a Vixen VMC110L to go with a 110mm Lunt EFR and a PST for a mod. Moving the 20mm Collimator lens into the front of ...
by AndiesHandyHandies
Tue May 22, 2018 5:48 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi

Where is the best free place to place images to give a link to here?

Andrew.
by AndiesHandyHandies
Thu May 17, 2018 4:01 pm
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Lunt 110mm ERF makes up for increased aperture Vixen VMC110L PST collimator lens moved forward a few cm. Standard PST black box. I am not really bothered with full disk option as with standard PST you had to gimbal eye about to see details. Just scan the scope. I prefer to see more detail in the ...
by AndiesHandyHandies
Thu May 17, 2018 9:30 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi, Rodastro got the PST block mounted on the back of the Vixen. Lunt 110mm derf just fits inside the dew cap. Taped on at the moment resting against felt circle on secondary cap. We got the PST apart. The Gold tube and Etalon came off on one go. When we stripped of the rubber tuning ring and took o...
by AndiesHandyHandies
Tue May 15, 2018 7:38 am
Forum: Solar Scope Modifications
Topic: Lenses for changing PST Focal Length
Replies: 6
Views: 642

Re: Lenses for changing PST Focal Length

Hi Mark, Thats what I thought. Are the Optisigma lenses a drop in? Personally the Lunt 110mm at 95mm would give F10 on the Meade 127mm Triplet to try. I am in the middle of a town on a windy ridge, near 'Windy Gap', so seeing might be a limitation. The Vixen would be more convenient to take out to r...
by AndiesHandyHandies
Mon May 14, 2018 9:25 am
Forum: Solar Scope Modifications
Topic: Lenses for changing PST Focal Length
Replies: 6
Views: 642

Re: Lenses for changing PST Focal Length

Hi Mark.

If you change the collimator do you need to have a matching re-focuser to balance out the abberations?

Are they a drop in fit? Are they bigger or smaller if not.

Thanks. Andrew.
by AndiesHandyHandies
Wed May 09, 2018 10:36 pm
Forum: Solar Scope Modifications
Topic: Lenses for changing PST Focal Length
Replies: 6
Views: 642

Re: Lenses for changing PST Focal Length

Hi

Are these simple lenses similar to those used in the PST Collimator?

https://america.optosigma.com/products/ ... oated.html

Andrew.
by AndiesHandyHandies
Mon May 07, 2018 11:38 am
Forum: Solar Scope Modifications
Topic: Lenses for changing PST Focal Length
Replies: 6
Views: 642

Re: Lenses for changing PST Focal Length

Hi Just come across Marks post with an alternative method of reaching focus without having to chop off a telescope tube. https://solarchatforum.com/viewtopic.php?f=9&t=12866&p=128272&hilit=pst+collimator+lens#p128272 Edmund Scientific stock negative achromats https://www.edmundoptics.co.uk/optics/op...
by AndiesHandyHandies
Mon May 07, 2018 8:58 am
Forum: Solar Scope Modifications
Topic: Lenses for changing PST Focal Length
Replies: 6
Views: 642

Lenses for changing PST Focal Length

Hi What size and focal length singlet lenses do I need to adapt the PST to work in collimation mode with a F7.5 telescope? Does the type of objective lens affect abberations? What sort of lens is the PTS objective, I assume a doublet as one was taken apart to polish off the failed ERF coating. Is a ...
by AndiesHandyHandies
Thu May 03, 2018 8:36 pm
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Re: Make a native F30 telescope better for Solar

Hi Christian, I have two etalon options to play with, The PST and Omega Bobs two 25mm 1.5nm H-alphas which are dielectric and a 25mm 40nm blocker he provides to protect them. I will take Marks advice and try my PST on the back of the Vixen VMC110L as is. I have a Lunt 110mm DERF so I was intrigued t...
by AndiesHandyHandies
Thu May 03, 2018 3:37 pm
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Re: Make a native F30 telescope better for Solar

Hi My mate is having seeing issues at the full focal length. He has been using a focal reducing lens before the positive collimator. He has tried various configurations with filters inside the focuser at native F30 and the current one outside with reducer. From his experiments a lens up the focuser ...
by AndiesHandyHandies
Thu May 03, 2018 3:31 pm
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Mark,

I will give the PST a try then.

Thanks. Andrew.
by AndiesHandyHandies
Thu May 03, 2018 11:22 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi

I think my 1.25" 3x ES Tele-extender order failed due to CC expiry.

When using TC can you work at less than F30?

Would a 2x ES TC work for a smaller brighter image, which would just fill the field I calculate.

Andrew.
by AndiesHandyHandies
Thu May 03, 2018 8:26 am
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Re: Make a native F30 telescope better for Solar

Hi Mark, Thanks for the information. I cannot re-call mentioning a 40mm diameter ERF for my mates option? " That 40mm ERF needs to sit half way down the tube ideally." Ah, the seperate Bobs ERF blocker to protect the filters is 40nm bandwidth and 20mm in diameter, we have new set(s) with the blocker...
by AndiesHandyHandies
Thu May 03, 2018 8:08 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Mark, Thats good to know. I will have to get a 1.25" Beloptic KG3 one as well to go in the short T2 terminated stub screwed in the back, to clear focus knob. 1. Bob forgot to send two replacement sets of H-Alphas when he split off the blocker which was causing excessive reflections. And he seems ...
by AndiesHandyHandies
Wed May 02, 2018 10:32 pm
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Re: Make a native F30 telescope better for Solar

Hi

The focal length is 2250mm. 6" F15.

Stopped down for F30.

So what diameter and negative focal length lens would we need for 20mm filters?

The spacings for the filter module to get reflections out of the path are 35nm pre-filter - 100mm - First H-alpha - 120mm - second H-alpha.

Andrew.
by AndiesHandyHandies
Wed May 02, 2018 10:26 pm
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi

I cannot find transmission diagrams for the Lunt ERF.

Would I need a Beloptik KG3 filter as well for the far IR?

Andrew.
by AndiesHandyHandies
Mon Apr 30, 2018 9:15 pm
Forum: Solar Scope Modifications
Topic: PST version and ERF insurance
Replies: 1
Views: 311

PST version and ERF insurance

Hi I have a PST Serial no 97166. It has a rusty? golden objective. It seems to work OK. Can see prominences and some small spots one day recently. I bought a 2" BeloptiK UV-IR blocked KG3 to put on the front as eye insurance, and etalon and filter protection. The dark spots seems to be a bit more co...
by AndiesHandyHandies
Mon Apr 30, 2018 8:47 pm
Forum: Solar Scope Modifications
Topic: Can i use my EDGEHD800 for Ha?
Replies: 10
Views: 848

Re: Can i use my EDGEHD800 for Ha?

Hi Does the Cassegrain affect the acceptance angle? And how do you calculate the effect? Primary F2 say and secondary magnification F5 to give net F10. Do you use a standard telecentric barlow to reach F30 or a special one to correct the acceptance angle reduction? Can you use a PST directly on the ...
by AndiesHandyHandies
Tue Apr 24, 2018 12:11 pm
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Mark,

For Bobs filters: "The effective index is close to 2.0."

Cheers. Andrew.
by AndiesHandyHandies
Tue Apr 24, 2018 6:43 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Mark,

Thank you for the reply and information.

So from experience we can stick with a collimator for Bobs filters?

Andrew.
by AndiesHandyHandies
Tue Apr 24, 2018 6:38 am
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Re: Make a native F30 telescope better for Solar

Hi Mark,

Its a doublet refractor stopped down to 77mm and a resulting focal ratio of F30.

It has a large rear focussing tube.

We have about 20mm apertures for the ERF blocker and 2 H-alphas. As you will know.

Thank you. Andrew.
by AndiesHandyHandies
Sat Apr 21, 2018 8:06 am
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi Mark Why are Omega Bobs filters better in a collimated beam than after a telecentric barlow? The usual advice is that telecentric is better. I have a PST so would this easily go with this scope for a mod? Its nearly F10 and plenty of rear focus, making it longer Fno, with the moving mirror focuss...
by AndiesHandyHandies
Sat Apr 21, 2018 7:05 am
Forum: Solar Scope Modifications
Topic: Make a native F30 telescope better for Solar
Replies: 10
Views: 748

Make a native F30 telescope better for Solar

Hi This is an Omega Bobs filter project. We know they are not brilliant but they are cheap and its a project. We had to send the first set of filters back because of excessive reflections from the combined ERF and H-Alpha. The replacement seperate 40nm ERF and h-alpha pairs are free of the problem. ...
by AndiesHandyHandies
Mon Apr 09, 2018 4:36 pm
Forum: Solar Scope Modifications
Topic: Vixen VMC110L F9.4 Maksutov as Solar Scope?
Replies: 28
Views: 1804

Re: Vixen VMC110L F9.4 Maksutov as Solar Scope?

Hi " For air spaced refractors this can take the form of a simple UV/IR cut or H-Alpha filter mounted internally. For oilled and Petzval refractors and any reflector, a front mounted energy rejection filter is required. The best of these are the Baader D-ERF types which will offer the best optical p...