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Optolyth TBS 100 APO/HDF (1 Viewer)
- Thread starter Bencw
- Start date
Greetings from Switzerland.
Having bought an used Optolyth TBS 100 recently, but mainly for astronomical use, I have to adjust some statements made and revive this thread.
With my decision I also relied on the nice work of @DRodrigues on pt-ducks: http://www.pt-ducks.com/cr-telescopes.htm that gives many interesting inputs.
As for my Optolyth TBS 100 with serial 1269xx, indeed that one regrettably has the mentioned ring in the ocular slot, preventing to use properly usual 1.25" eyepieces, since it is too small to sink in those eyepieces. So the stated circumstance that devices with a bigger or lower serial number do / do not allow the use of 3rd-party eyepieces obviously does not apply, as my case shows.
I've asked optolyth without response yet, if that ring can be removed without consequences (IMO it appears so). So I'm wondering @Bencw , if you finally maybe just tried to remove that ring and if there where "consequences"?
Thank you for your inputs.
Pics showing my ocular slot and the approx. measurements. Inner diameter of the black ring was measured with caliper.
regards
EDIT: 3rd pic shows also an Optolyth TBS 100 ocular slot owned by another guy I'm corresponding with. It also has such a ring, but without the 2 notches, but there the 1.25" eyepieces DO indeed fit and he is able to use the spotting scope with 1.25" pieces without restrictions. His model also has an other difference. There is an outer, small thread around the slot that allows the direct attachment of an adapter for fotographic use.
Having bought an used Optolyth TBS 100 recently, but mainly for astronomical use, I have to adjust some statements made and revive this thread.
With my decision I also relied on the nice work of @DRodrigues on pt-ducks: http://www.pt-ducks.com/cr-telescopes.htm that gives many interesting inputs.
As for my Optolyth TBS 100 with serial 1269xx, indeed that one regrettably has the mentioned ring in the ocular slot, preventing to use properly usual 1.25" eyepieces, since it is too small to sink in those eyepieces. So the stated circumstance that devices with a bigger or lower serial number do / do not allow the use of 3rd-party eyepieces obviously does not apply, as my case shows.
I've asked optolyth without response yet, if that ring can be removed without consequences (IMO it appears so). So I'm wondering @Bencw , if you finally maybe just tried to remove that ring and if there where "consequences"?
Thank you for your inputs.
Pics showing my ocular slot and the approx. measurements. Inner diameter of the black ring was measured with caliper.
regards
EDIT: 3rd pic shows also an Optolyth TBS 100 ocular slot owned by another guy I'm corresponding with. It also has such a ring, but without the 2 notches, but there the 1.25" eyepieces DO indeed fit and he is able to use the spotting scope with 1.25" pieces without restrictions. His model also has an other difference. There is an outer, small thread around the slot that allows the direct attachment of an adapter for fotographic use.
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I can state the described black ring can be removed. However, it is one unique piece that includes the glass at the bottom.
Removing it, the nitrogenfilled unit is left open. Surely not recommendable.
So there must be at least 2 models of that optolyth TBS 100 what concerns the slot for the oculars. As shown in the pics above 1 and 3.
regards
Removing it, the nitrogenfilled unit is left open. Surely not recommendable.
So there must be at least 2 models of that optolyth TBS 100 what concerns the slot for the oculars. As shown in the pics above 1 and 3.
regards
DRodrigues
Well-known member
It would be useful to mention the serial number of the scope of the pic 3...
Maybe on your sample Optolyth used "old" stock rings...
Don't know also if it has something related to scope models - mine are straight view and both of your pics are angled.
Hi,
i am Andi, the guy who is corresponding with CHnuschti in a german astronomical forum. The serial number of my TBS is 135110 with white script on it only.
@DRodrigues I have the same thoughts. Maybe old stock parts used during version change or different serial numbers between TBG and TBS.
i am Andi, the guy who is corresponding with CHnuschti in a german astronomical forum. The serial number of my TBS is 135110 with white script on it only.
@DRodrigues I have the same thoughts. Maybe old stock parts used during version change or different serial numbers between TBG and TBS.
DRodrigues
Well-known member
Thanks for the info Andi, I will update at my web page.
For those that have older versions and want to use astro eps there are 2 solutions:
- to use a special barlow cell TS 2.6x GPC that has the disadvantage of inducing an increase of about 1.6x magnifications - it varies with the eps - and have "dark" coatings - this last detail might be useful for bright astro targets. Beware that the TS 1,6x GPC is different and most probably will not work;
- to get wider FOVS you might use some 2" eps as shown at using 2" eps on 1.25" binoviewers - with the ep shown I obtain wider FOV than with any 1.25" ep on my TBGs 100. If you want to connect the 2" ep to the scope you might want to do what I did - get someone to "machine" a T2 male thread on the exterior of the Optolyth astro adapter - see photo at the end of cr-telescopes
