• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

TSN-883 focal length (1 Viewer)

ve2vk

Member
This is the first time I'm posting a question regarding the Kowa TSN-883
scope. I would like to know the focal length of my scope. I purchased the Kowa 1 1/4 astro adaptor which will be used with Pentax XW-10-14 and 20 astro eyepieces.

Any help appreciated,
Bruno.
 
I think It's 500mm? You should get some excellent views with the Pentax EP's Do you have the Kowa
zoom?
 
Last edited:
This is the first time I'm posting a question regarding the Kowa TSN-883
scope. I would like to know the focal length of my scope. I purchased the Kowa 1 1/4 astro adaptor which will be used with Pentax XW-10-14 and 20 astro eyepieces.

Any help appreciated,
Bruno.

Bruno , Let us know how well your Pentax XW eyepieces perform on your Kowa 883 with your Kowa Astro adapter.
 
TSN-883 with Pentax eyepieces.

I purchased the scope with the TSN-11Z zoom eyepiece. The view is amazing.Later on I acquired the 1.6X extender which is nice, however the loss in light is noticeable. I decided to order the astropiece adaptor since my previous scope was a Pentax PF65ED AII. The view is outstanding with these eyepieces on the TSN-883. The only problem is that I'm unable to focus at infinity..

This afternoon I screwed the 1.6X extender with the astropiece adaptor and the XW20 Pentax eyepiece. The view was excellent. The loss in light was not as noticeable compared to the TSN-11Z zoom. So with 1.6X that would be 40X. I stopped short of experimenting with the other eyepieces. We're going through a coldspell which should last for the next few days. The temperatures are dipping to -25c. I will wait for favourable weather and come up witha more extensive report..

Thanks from Bruno.
 
I purchased the scope with the TSN-11Z zoom eyepiece. The view is amazing.Later on I acquired the 1.6X extender which is nice, however the loss in light is noticeable. I decided to order the astropiece adaptor since my previous scope was a Pentax PF65ED AII. The view is outstanding with these eyepieces on the TSN-883. The only problem is that I'm unable to focus at infinity..

This afternoon I screwed the 1.6X extender with the astropiece adaptor and the XW20 Pentax eyepiece. The view was excellent. The loss in light was not as noticeable compared to the TSN-11Z zoom. So with 1.6X that would be 40X. I stopped short of experimenting with the other eyepieces. We're going through a coldspell which should last for the next few days. The temperatures are dipping to -25c. I will wait for favourable weather and come up witha more extensive report..

Thanks from Bruno.
I am a little confused. The Pentax XW eyepieces will not come to focus when used with the 1.6x extender & with the astro eyepiece adapter ?
How about the Pentax XW eyepieces with astro adapter without the 1.6x extender ?
 
Which astro adapter are you using? The grub screw version is a little shorter than the full set screw verson. This allows the end of the eyepiece to sink further into the scope body. Getting the Pentax eyepieces deep enough to reach infinity focus has always been a challenge. Even resting the eyepiece bottom against the waterproofing window hasn’t been deep enough to reach infinity with the Pentax 10mm. But, I haven’t tried it with the focal extender.

Best,
Jerry
 
I'm using the the thumbscrew astro adaptor. The Pentax XW eyepieces don't come into focus at infinity. I inserted the focal extender the XW-14 and XW-20 come into focus at infinity. I haven't tried the XW-10 yet for lack of time
and when the temperature is more clement.

Bruno.
 
Warning! This thread is more than 6 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Users who are viewing this thread

Back
Top