Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

RACI Finder that takes an 1.25" eyepiece


Recommended Posts

I've been considering getting a RACI finder scope for my dob to replace the straight through 9x50 finder scope. One thought that occurred to me this evening is that I have an ES68 24mm eyepiece that isn't seeing much use now. Could I use this in a finder scope? I believe you can get RACI finders that take a 1.25" eyepiece?

Could anyone recommend such a finder or offer thoughts/advice on this type of set up please? Does this give much benefit in practise versus a standard RACI? 

Link to comment
Share on other sites

  • Replies 49
  • Created
  • Last Reply

I have a Russell Optics 60mm finder scope similar to this 70mm Orion finder scope.  The problem I found is that all up, with rings, tube, diagonal, and eyepiece, the total weight massively throws off your scope's balance for not a lot of gain compared to adding DSCs, which is the route I ultimately went.  DSCs don't throw off your scope's balance at all and are a lot more useful for finding difficult objects like Uranus, Neptune, and tiny PNs.

Link to comment
Share on other sites

Neil I have used many types of finderscopes and because my main interest in DSOs and star hopping I recently purchase this item for my 12" Dob.

 https://www.telescopehouse.com/accessories/altair-80mm-maxi-finder-finder-scope-package.html

I need to balance the scope by placing a magnetic weight but the system is very good. Last night whilst still in twilight I was able to pick up double stars in Libra. OK I might have managed this with a 50mm right angle correct image finderscope but I can change the EPs which includes my 8-24mm TeleVue zoom.

Link to comment
Share on other sites

1 hour ago, Mark at Beaufort said:

Neil I have used many types of finderscopes and because my main interest in DSOs and star hopping I recently purchase this item for my 12" Dob.

 https://www.telescopehouse.com/accessories/altair-80mm-maxi-finder-finder-scope-package.html

I need to balance the scope by placing a magnetic weight but the system is very good. Last night whilst still in twilight I was able to pick up double stars in Libra. OK I might have managed this with a 50mm right angle correct image finderscope but I can change the EPs which includes my 8-24mm TeleVue zoom.

That’s an impressive finder. It sounds like a good little scope in its own right! I hadn’t thought about balancing the scope so glad you mentioned.

Link to comment
Share on other sites

13 minutes ago, Littleguy80 said:

That’s an impressive finder. It sounds like a good little scope in its own right! I hadn’t thought about balancing the scope so glad you mentioned.

That is like one of mine. Also 60mm done. Little rich field scope in its own right. 

The SW 72 ED looks like a good substitute. ST 80s are heavier but also qualify. 

Link to comment
Share on other sites

3 hours ago, Mark at Beaufort said:

Neil I have used many types of finderscopes and because my main interest in DSOs and star hopping I recently purchase this item for my 12" Dob.

 https://www.telescopehouse.com/accessories/altair-80mm-maxi-finder-finder-scope-package.html

I need to balance the scope by placing a magnetic weight but the system is very good. Last night whilst still in twilight I was able to pick up double stars in Libra. OK I might have managed this with a 50mm right angle correct image finderscope but I can change the EPs which includes my 8-24mm TeleVue zoom.

That is a very tempting to add to my Dob... Thanks for the info Mark :) 

Link to comment
Share on other sites

DSC_1753.thumb.JPG.a455f1b2658fa57962403782a99bee49.JPG

Mine takes 1.25" eyepieces, see photo (with RDF strapped on and DIY dew shield). It's a TS branded job, they have a few models with this feature.

This one is 60mm, nice and bright. A bit heavier than bog standard, but not too much.

I tried a Baader Polaris crosshair EP - would have been great for targeting - but it won't come to focus...still working on that one. No focus problems with Plossls or Panoptics.

Image is a bit blurry near the edge.

 

Link to comment
Share on other sites

1 hour ago, iPeace said:

DSC_1753.thumb.JPG.a455f1b2658fa57962403782a99bee49.JPG

Mine takes 1.25" eyepieces, see photo (with RDF strapped on and DIY dew shield). It's a TS branded job, they have a few models with this feature.

This one is 60mm, nice and bright. A bit heavier than bog standard, but not too much.

I tried a Baader Polaris crosshair EP - would have been great for targeting - but it won't come to focus...still working on that one. No focus problems with Plossls or Panoptics.

Image is a bit blurry near the edge.

 

TS 20mm Erfle with cross hair might suit your need. They also do a 32mm 2 inch crosshair for main scopes.

Link to comment
Share on other sites

This really has me thinking now. The Altair 80mm finderscope Mark suggested would give just under a 5 degree TFOV  with the ES68 24mm. Is this like having a little wide field scope on top of the dob? Add an OIII filter and get some nice views of the Veil or NAN? 

Link to comment
Share on other sites

12 minutes ago, Littleguy80 said:

This really has me thinking now. The Altair 80mm finderscope Mark suggested would give just under a 5 degree TFOV  with the ES68 24mm. Is this like having a little wide field scope on top of the dob? Add an OIII filter and get some nice views of the Veil or NAN? 

Love mine. Especially being able to use my own eps. A UHC filter might be better using as a finder filter than OIII, which coold be too dark. Helical focusing is easy.

Link to comment
Share on other sites

16 minutes ago, Littleguy80 said:

This really has me thinking now. The Altair 80mm finderscope Mark suggested would give just under a 5 degree TFOV  with the ES68 24mm. Is this like having a little wide field scope on top of the dob? Add an OIII filter and get some nice views of the Veil or NAN? 

Neil I am hoping to view some wide fields when astro darkness returns. I can tell that the Sun was great in white light using the TeleVue zoom. I also have a ES68 24mm EP and it works very well in this finderscope. I also bought these rings - http://www.opticstar.com/Run/Astronomy/Astro-Accessories-Telescopes-Opticstar.asp?p=0_10_5_1_8_111 - Future travel set up maybe ?.

Link to comment
Share on other sites

4 minutes ago, Mark at Beaufort said:

Neil I am hoping to view some wide fields when astro darkness returns. I can tell that the Sun was great in white light using the TeleVue zoom. I also have a ES68 24mm EP and it works very well in this finderscope. I also bought these rings - http://www.opticstar.com/Run/Astronomy/Astro-Accessories-Telescopes-Opticstar.asp?p=0_10_5_1_8_111 - Future travel set up maybe ?.

This seems like such a great idea. I quite fancy something wide field but don’t want to have a second scope/mount. This feels like best of both worlds. As you say, Mark, added bonus is a nice travel setup into the bargain!

Thank you for the great suggestion! 

Link to comment
Share on other sites

1 hour ago, Mark at Beaufort said:

I can tell that the Sun was great in white light using the TeleVue zoom.

What would be required to use this as a solar scope? I’ve never done any solar viewing but am keen to try!

Link to comment
Share on other sites

3 hours ago, iPeace said:

DSC_1753.thumb.JPG.a455f1b2658fa57962403782a99bee49.JPG

Mine takes 1.25" eyepieces, see photo (with RDF strapped on and DIY dew shield). It's a TS branded job, they have a few models with this feature.

This one is 60mm, nice and bright. A bit heavier than bog standard, but not too much.

I tried a Baader Polaris crosshair EP - would have been great for targeting - but it won't come to focus...still working on that one. No focus problems with Plossls or Panoptics.

Image is a bit blurry near the edge.

 

A really like this set up btw! I see TS optics do an 80mm version too

Link to comment
Share on other sites

25 minutes ago, Littleguy80 said:

What would be required to use this as a solar scope? I’ve never done any solar viewing but am keen to try!

Neil you just need a solar filter like this - https://www.firstlightoptics.com/solar-filters/astrozap-baader-solar-filter.html

I use my TeleVue 8-24 zoom and the 8mm setting gives a mag of 41X. Something like a 6mm or 7mm would give a nice view.

Link to comment
Share on other sites

Hi Neil,

I have one of these on my Tak FS128. It takes 1.25" eyepieces and has a helical focuser and illuminator..

"Stellarvue 9x50 Top Rated RA Correct Image Finder Scope - Matte Black - F050M2"

I'm very happy with mine?.

Dave

IMG_20180622_205403385.jpg

IMG_20180622_205346226.jpg

IMG_20180622_205413997.jpg

IMG_20180622_205424222.jpg

Link to comment
Share on other sites

1 minute ago, F15Rules said:

Hi Neil,

I have one of these on my Tak FS128. It takes 1.25" eyepieces and has a helical focuser and illuminator..

"Stellarvue 9x50 Top Rated RA Correct Image Finder Scope - Matte Black - F050M2"

I'm very happy with mine?.

Dave

IMG_20180622_205403385.jpg

IMG_20180622_205346226.jpg

IMG_20180622_205413997.jpg

IMG_20180622_205424222.jpg

Thanks Dave! Looks good. How does the illuminated part work? Is that only with a specific eyepiece or any eyepiece you use with it?

Link to comment
Share on other sites

Hi Neil,

I bought my finder used and it was missing the original eyepiece. I was lucky and found a 23mm illuminated eyepiece here on SGL classifieds at a good price. You can find similar illuminated eyepieces on ebay..Just search "illuminated eyepiece". Be aware though that many of these are 12.5mm focal length and you probably want more like 23-25mm - my finder is 50mm F4, so the 23mm ep I have gives c 8.7x magnification.

I can also recommend the Altair 10x60 finderscope which comes with rings and mounting bracket, 23mm eyepiece with illuminator etc complete, at around £169 I think. I owned one and really liked it, goes quite deep being 60mm, but is a bit soft after about 65-70% out..

Hope that helps,☺

Dave

Link to comment
Share on other sites

On 22/06/2018 at 15:01, Littleguy80 said:

How does the illuminated part work? Is that only with a specific eyepiece or any eyepiece you use with it?

As far as I've ever seen, illumination is eyepiece dependent.  It takes a specially designed eyepiece with a reticle, an illumination port perpendicular to the reticle, an illuminator, and a focusable upper part of the eyepiece to bring the reticle to focus independently of focus for the main scope.

Link to comment
Share on other sites

Louis D is correct. The 80mm Finderscope that I puchased included a reticle eyepiece. You adjust the top part to bring the cross lines to focus. If you want you can then turn on the red light which illuminates the cross lines to whichever brightest you require.

Link to comment
Share on other sites

I've also found that defocusing a reasonably bright star will back light an unilluminated reticle just fine for centering purposes.

Avoid illuminators that look like this one:

EI2400__69869.1402351485.1200.1200.jpg?c

I've had no end of problems with mine.  They unscrew in the wrong places causing internal wires to pull free of where they are soldered.  Resoldering is just a temporary fix I've found.  They are also much too bright until they just about turn off.

I've had much better luck with this style of illuminator:

ag-ire12.5-2_1_1.jpg

It just seems a lot more robust and the brightness is much more controllable down to a reasonable level.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.