TheSkySearchers-Welcome!

Lady Fraktor wrote: ↑Sun Sep 29, 2019 4:47 pm(...)The other is how the tube interior is currently a bright surrounding.

Is this from the eyepiece-side? ( I suspect three spacers at the other end)
Never mind, my old Master would give you an "A".

It would be an interesting experiment to baffle the dew shield too.

Not very long ago an opticien wanted to show me some children's fingerprints on the corrector of the 14 inch Meade of the observatory. He pointed it out with a rather bright light. Meanwhile someone was observing through it; he didn't notice it. I didn't believe that and wanted to see it myself. I could not. The light was effectively put on hold by the inside baffle. He told me the wisdom "As long as the incident light doesn't reach the eyepiece, not much harm can be done."

I am not sure if baffling the dewshield will have noticeable effect.

I think that whether dew shield baffling provides a benefit or not depends on the immediate environment. I noticed at my previous dark rural site that my SV ED80A started showing intermittent reflected light from the dew shield when a neighbor installed an intermittent security light. Since the light was well outside the TFOV some additional treatment of the dew shield is called for in an urban / suburban environment.

John: The image is through the focuser facing into a brightly lit room, and thank you for your comments
I removed the factory baffles and made five new ones. The shadow of the forward baffle falls on the face of the following baffle.

nFA: The 150mm gets used most times in a suburban environment so stray light can be an issue at times.

Lady Fraktor wrote: ↑Mon Sep 30, 2019 5:38 am nFA: The 150mm gets used most times in a suburban environment so stray light can be an issue at times.

I suspected as much. I may have to do something similar with my SV. I have a 24 hour porch light illuminating my southern sky exposure.

It is a quite similar situation in my backyard.
In the past I made a very long dewshield (no baffles) for my 60/900 refractor. More than 36 cm long. It worked up to a certain level.I just made a simple drawing of it. It seems to me that a combination of a long long shield AND baffles works best.

The current dewshield is 2.5x the aperture (380mm) but I believe I have enough material to make one at 3x (450mm)

notFritzArgelander wrote: ↑Mon Sep 30, 2019 5:51 am

Lady Fraktor wrote: ↑Mon Sep 30, 2019 5:38 am nFA: The 150mm gets used most times in a suburban environment so stray light can be an issue at times.

I suspected as much. I may have to do something similar with my SV. I have a 24 hour porch light illuminating my southern sky exposure.

The person on one side has a large shed in the garden which has a automatic security light installed on it. It is randomly set off by cats or other animals.

Lady Fraktor wrote: ↑Mon Sep 30, 2019 4:20 pm

notFritzArgelander wrote: ↑Mon Sep 30, 2019 5:51 am

Lady Fraktor wrote: ↑Mon Sep 30, 2019 5:38 am nFA: The 150mm gets used most times in a suburban environment so stray light can be an issue at times.

I suspected as much. I may have to do something similar with my SV. I have a 24 hour porch light illuminating my southern sky exposure.

The person on one side has a large shed in the garden which has a automatic security light installed on it. It is randomly set off by cats or other animals.

I've tried the polite request route. Utter failure.

I have tried also, he moved the lights to pointing at the ground instead of straight out and turned the timer down to five minutes from a half hour.
Small victories I guess. I have offered to buy new lights but so far nothing has changed.

Hi Gabby,

If you are predominantly trying to exclude one troublesome light source and it is a single light source, have you considered building a one sided extended dewcone? Then the long side shields but there is no other side for the light to bounce off.
Another option is a blockout blind at the fence line.

Joe

An interesting idea Joe

Gabby

You can try one made out of some thin black card & an elastic band to test it out before investing time into a metal build.

Joe

Ive go 2 big in my Bresser approxomaly 1/3 into the scope its sticking about 1 cm from the tube wall into the scope ,and the 2nd is in the 2nd off 1/3 lenght off the scope its sticking about 4 cm into the scope..its just around 1 mm thick ---and a little rim 3 mm height its 10 cm into the scope .counting from the big lens side..3,0 mm thick metal body on this scope---,,,and ita also a structured metal handle,,and rings----its realy nice to handle--no wimpy things here--