RACI, SchmACI.....

[Stu]

Hopefully you know how to say the above.....

No, I’m not trying to put down RACI finders really, but I did want to have a little love-in for those much maligned straight-through finders. I have RACIs on my scopes apart from the Vixen Fluorite and Tak Mewlon which both have straight-through finders and having used them a fair bit recently can definitely see the advantages.

The downside of a straight-through is obviously the gymnastics that you have to pull to get your eye in the right place to view, but once there they do have a strong advantage over RACIs. If you keep both eyes open then you can view the naked eye star and the one through the finder at the same time. First off, being in this position helps you to point the scope in the right sort of direction anyway, but additionally when you are approaching the target they both end up converging in your vision, making it very obvious when you are in the right spot.

A RACI works very well in conjunction with an RDF or Telrad, use the Telrad to get basically in the right place then switch to the RACI to finish the job. With a Telrad you still have to get down behind the glass to see the circles, so I guess the straight through does it all in one unit and in one go.

Now, I suffer from my fair share of neck stiffness and pain so fully understand the comfort issues, but for our younger more agile members, don’t disregard these finders as they can be surprisingly effective. They are also cheaper to pick up, especially a 9x50 standard unit which is being sold off after being replaced by the shiny new RACI. Worth considering if after a larger finder on a budget anyway.

Thank you for listening to my ramblings 😉

[JeremyS]

4 minutes ago, Stu said:

Hopefully you know how to say the above.....

No, I’m not trying to put down RACI finders really, but I did want to have a little love-in for those much maligned straight-through finders. I have RACIs on my scopes apart from the Vixen Fluorite and Tak Mewlon which both have straight-through finders and having used them a fair bit recently can definitely see the advantages.

The downside of a straight-through is obviously the gymnastics that you have to pull to get your eye in the right place to view, but once there they do have a strong advantage over RACIs. If you keep both eyes open then you can view the naked eye star and the one through the finder at the same time. First off, being in this position helps you to point the scope in the right sort of direction anyway, but additionally when you are approaching the target they both end up converging in your vision, making it very obvious when you are in the right spot.

A RACI works very well in conjunction with an RDF or Telrad, use the Telrad to get basically in the right place then switch to the RACI to finish the job. With a Telrad you still have to get down behind the glass to see the circles, so I guess the straight through does it all in one unit and in one go.

Now, I suffer from my fair share of neck stiffness and pain so fully understand the comfort issues, but for our younger more agile members, don’t disregard these finders as they can be surprisingly effective. They are also cheaper to pick up, especially a 9x50 standard unit which is being sold off after being replaced by the shiny new RACI. Worth considering if after a larger finder on a budget anyway.

Thank you for listening to my ramblings 😉

Spot on Stu. I could never really understand the RACI enthusiasm.

Actually, I could never get my head around the RACI enthusiasm 🙂

 

[ScouseSpaceCadet]

Thanks for rambling Stu, some good points... However, those of us who's brains work better without having to mentally visualise the sky the right way up while looking through a straight through finder like our RACIs... 🙄😀

 

[Stu]

22 minutes ago, ScouseSpaceCadet said:

Thanks for rambling Stu, some good points... However, those of us who's brains work better without having to mentally visualise the sky the right way up while looking through a straight through finder like our RACIs... 🙄😀

 

Tee hee! Well that’s kind of the point I’m trying to make too. If used if the way I mention, you get the correct image version of the target in one eye, then the view through the finder becomes less relevant as when in target both merge into one. Now, I fully accept that when needing to pin down a tough target by matching star fields etc it can get more complex, although Skysafari allows you to match these views too so where the problem?

🤣🤣 I know, I know, I’m not going to win this one but am not really trying to. Just trying to show they are not as bad as people may make out. Actually when I first started using RACI finders I always pushed the scope the wrong way anyway because I had got so used to the left right reversed view in my refractors.

[John]

I've used lots of both types and they all worked

RACI's on all my scopes now though. Using the straight through on the Tasco the other night reminded me why.

I didn't even get on with the lovely little Tak 30mm straight through ...... my Tak now carries a Skywatcher RACI 

Not a bad finder though - Venus slim phase was clear at just 6x with it this evening.

Glad some folks like the straight throughs though

 

[F15Rules]

1 hour ago, JeremyS said:

Actually, I could never get my head around the RACI enthusiasm

That's interesting Jeremy..actually, I could never get my head around straight through finders..literally!😂😂

Seriously, though, there must be a reason that most Japanese observers use straight through finders- and Takahashi don't make RACI versions of their superb finders, neither do Vixen AFAIK..they seem to think that it is somehow "compromising" to use a diagonal, whether on a finder or on the main tube?

I have owned 3 optically wonderful straight through finders..a quite superb TAL 8x50 with helical focusing, built like a tank and sharp as a razor, the lovely  illuminated Tak 50mm finder that came with my FS128, (a perfect little miniature scope) and a Japan built 7x50mm that came with my older Vixen ED103s - this one had illumination too.

All of the above were excellent miniature scopes but if I was viewing anything much above 10 degrees or more above the celestial equator, they were a real pain in the neck (again, literally) to use.

With some regret I sold my Tak finder, but I kept the original Tak Green bracket, and I have used a Skywatcher 9x50 RACI for about the last 2 years or so. It's so much more comfortable to use, even though it's a bit soft at the edges compared to the Tak. 

The first picture shows the FS128 with the original straight through finder, the second with the SW Raci..personally, I like the first one more to look at, and the second one more to look through..

I wish Tak (or Vixen) would offer customers a choice of Tak branded straight through OR Raci models, then we could choose what suits us best as individuals, whilst still keeping our OTAs as fully Tak-y!😊

Dave

Edited May 11, 2020 by F15Rules

[Stu]

@F15Rules Dave, it does seem to be a peculiarly Japanese thing doesn’t it? I wonder why? I do agree it would be nice to have options for RACIs from Tak. I seem to recall someone using one of these to convert a Tak finder to a RIght Angle, might need some missing I’m not sure.

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5950_TS-Optics-90--Winkeleinblick-fuer-Skywatcher-Polsucher-D-30mm.html

[Captain Scarlet]

I suspect that the “convergence” phenomenon is something you can acquire once you’re very experienced, a “professional skill” if you like. I might give it a go now that I have a small amount of experience under my belt.

I do observe though that RACI finders are the single item in the “for sale” section that never last more than a few minutes!

[Stu]

18 minutes ago, Captain Magenta said:

I do observe though that RACI finders are the single item in the “for sale” section that never last more than a few minutes!

Very true!

[Rainmaker]

1 hour ago, John said:

I've used lots of both types and they all worked

RACI's on all my scopes now though. Using the straight through on the Tasco the other night reminded me why.

I didn't even get on with the lovely little Tak 30mm straight through ...... my Tak now carries a Skywatcher RACI 

Not a bad finder though - Venus slim phase was clear at just 6x with it this evening.

Glad some folks like the straight throughs though

 

Had RACIs before, mainly RDF (Baader SkySurferV) now,  but I agree that the Tak 6x30 is not bad, in fact it probably has the finest optics of any finder I have used....

[Guest]

I must be lucky, as I can do the 'convergence' thing without much effort.  I think it comes from keeping both eyes open whilst aiming at a target, in archery.  I'm planning to get a RACI finder because it's hard to do a contortionist impression, whilst looking at the straight through a finderscope pointed near the zenith!

Edited May 11, 2020 by Guest

[Louis D]

1 hour ago, Stu said:

Now, I suffer from my fair share of neck stiffness and pain so fully understand the comfort issues

Most RACI simply don't have enough eye relief to use with eyeglasses, so I've been making my own with a cheap 70mm f/4.3 "toy" scope, some PVC plumbing parts, a cheap 2" dielectric diagonal I had sitting around, and a widest field 2" eyepiece yet to be settled upon.  It will work out to about an 8x70 to 10x70 finder with about an 8 to 9 degree true field of view.  Severe field curvature is the major issue right now.  I don't have a spare TSFLAT2 to use in it at the moment.

I recently injured my neck in a fall to the point that it is incredibly painful to use a unit power finder or straight through finder now, so I've been aiming strictly with the green laser sight lately.  Now that is an incredibly intuitive aiming device.  I know y'all in the UK are incredibly opposed to them.

It also hurts just to look down into a diagonal when bending at the neck, so I have to back up and bend more at the waist.  Hopefully it heals up over the next few weeks/months.  I'd go to physical therapy, but they're all closed due to social distancing.

[AdeKing]

1 hour ago, Stu said:

Tee hee! Well that’s kind of the point I’m trying to make too. If used if the way I mention, you get the correct image version of the target in one eye, then the view through the finder becomes less relevant as when in target both merge into one. Now, I fully accept that when needing to pin down a tough target by matching star fields etc it can get more complex, although Skysafari allows you to match these views too so where the problem?

🤣🤣 I know, I know, I’m not going to win this one but am not really trying to. Just trying to show they are not as bad as people may make out. Actually when I first started using RACI finders I always pushed the scope the wrong way anyway because I had got so used to the left right reversed view in my refractors.

I'm with you Stu, I really like the little Celestron 6x30 straight through that came with my XLT102 ED tube.

I've never had an issue with using the straight through finders with both eyes open and find it intuitive to use that way.

However, I can see how confusing it'd be looking through it with only one eye open.

The acrobatics to use the straight thru finders can get interesting, but now I'm using the GP on a tall pillar mount its much more comfortable. It's tall enough that even using the polar scope to align is bearable and doesn't require crawling around on your knees.

[Second Time Around]

4 minutes ago, Louis D said:

Most RACI simply don't have enough eye relief to use with eyeglasses, so I've been making my own with a cheap 70mm f/4.3 "toy" scope, some PVC plumbing parts, a cheap 2" dielectric diagonal I had sitting around, and a widest field 2" eyepiece yet to be settled upon.  It will work out to about an 8x70 to 10x70 finder with about an 8 to 9 degree true field of view.  Severe field curvature is the major issue right now.  I don't have a spare TSFLAT2 to use in it at the moment.

I recently injured my neck in a fall to the point that it is incredibly painful to use a unit power finder or straight through finder now, so I've been aiming strictly with the green laser sight lately.  Now that is an incredibly intuitive aiming device.  I know y'all in the UK are incredibly opposed to them.

It also hurts just to look down into a diagonal when bending at the neck, so I have to back up and bend more at the waist.  Hopefully it heals up over the next few weeks/months.  I'd go to physical therapy, but they're all closed due to social distancing.

Sorry to hear that, Louis. Best wishes for a speedy recovery from a fellow neck sufferer.

[John]

26 minutes ago, Rainmaker said:

Had RACIs before, mainly RDF (Baader SkySurferV) now,  but I agree that the Tak 6x30 is not bad, in fact it probably has the finest optics of any finder I have used....

The TAL finders from Russia are very good optically as well. Not as nicely finished as the Tak but optically very nice indeed.

[johninderby]

The old William Optics 7x50 finder had great optics but discontinued many years ago. Beautifully made piece of kit. If only it hadn’t been straight through would have kept it. 

Edited May 11, 2020 by johninderby

[michael8554]

I use the two-eye method with a Telrad, which puts the object close to centre of a 9x60 RACI.

Michael

[JeremyS]

1 hour ago, Louis D said:

Most RACI simply don't have enough eye relief to use with eyeglasses, so I've been making my own with a cheap 70mm f/4.3 "toy" scope, some PVC plumbing parts, a cheap 2" dielectric diagonal I had sitting around, and a widest field 2" eyepiece yet to be settled upon.  It will work out to about an 8x70 to 10x70 finder with about an 8 to 9 degree true field of view.  Severe field curvature is the major issue right now.  I don't have a spare TSFLAT2 to use in it at the moment.

I recently injured my neck in a fall to the point that it is incredibly painful to use a unit power finder or straight through finder now, so I've been aiming strictly with the green laser sight lately.  Now that is an incredibly intuitive aiming device.  I know y'all in the UK are incredibly opposed to them.

It also hurts just to look down into a diagonal when bending at the neck, so I have to back up and bend more at the waist.  Hopefully it heals up over the next few weeks/months.  I'd go to physical therapy, but they're all closed due to social distancing.

Is that a zero power laser Louis? 🙂

 

Edited May 11, 2020 by JeremyS

[johninderby]

If you mounted a stright through finder backwards so you looked through the wrong end you would have a negative power finder. 😁😁😁

Edited May 11, 2020 by johninderby

[Louis D]

53 minutes ago, johninderby said:

If you mounted a stright through finder backwards so you looked through the wrong end you would have a negative power finder. 😁😁😁

You're just baiting me, aren't you? 🤔

[Louis D]

1 hour ago, JeremyS said:

Is that a zero power laser Louis? 🙂

 

No optics to be looked through, so not sure how to classify it. 🙄