26 replies to this topic

[TeslaTrek]

I believe I purchased the SolarMax back in 2013 and it has worked like a champ until now.  I can no longer find the sun in the eyepiece! (Yes lens cap off and in center of finder)

 

I think something is out of alignment / colimination with the scope.  I purchased it from OPT then and they are out of business.  I believe Meade purchased Coranado and now Meade is out of business.  I googled Meade and it showed that Meade was purchased by Orion.  And now I see Orion Telescopes is out of business as of July 2024.

 

So who do I call for repair?

 

I tried adjusting the tilt wheel, the tuning lever and played with the turning ring on the objective.

 

Has anyone else had this issue with their Coronado and can give me some tips on repair?

 

thanks

Jim

[PETER DREW]

Are you sure that the telescope and the finder are aligned?  The field is probably only a degree.

[Scope2]

Hi Jim sorry to hear your scopes giving you trouble.  Does it work in single stack mode? 

Look a the filters in the Diagonal to see if rust has formed and post picture. Just some things to check;

 

                                                    Best Regards Pat Mog'

[bigdob24]

This would be a great question for Solar Observing and Imaging forum.

There are a number of possibilities, I’m not really familiar with SolarMax but if you have the moderator move it you will get answers.

If the scope needs repair contact Lunt as they now do repairs on other brands. 

[TeslaTrek]

Thanks for pointing that out.    I clicked to fast thinking I was clicking on the solar observing instead of solar system.

[12BH7]

Great bunch over on the Solar forum. Either way, do post what happens.

[BYoesle]

Has the finder become misaligned?

 

Remove the blocking filter, and aim the telescope with the finder at the sun. An red image of the sun should exit the focuser and be centered on axis. If it's not, the finder is misaligned.

 

If the image is centered and bright, the next thing to check is the ITF (induced transmission filter) in the blocking filter. This may have deteriorated, and can be replaced easily if it has. A careful inspection of the first element (towards the objective) of the BF will show it to be cloudy verses transparent if it has "rusted."

 

 

It can be replaced with the BelOptik ITF replacement filter.

 

If neither of these fixes the problem, then contact Lunt directly for a repair evaluation and authorization.

[TeslaTrek]

I thought the BF filter could not be removed.  But I'll try tomorrow - thanks.

[BYoesle]

The telescope comes with a BF15 or a BF30. Either should be accessible with possibly some disassembly required.

[TeslaTrek]

So this afternoon, I tried pretty hard to remove the BF15 filter, or more precisely the diagonal.  I am hesitant to grab the focusing tube with a wrench,  or should I?

thanks

 

[BYoesle]

 

Turn this thumbscrew counterclockwise until it becomes obviously loose:

 

 

This will enlarge the compression clamp holding the diagonals nosepiece.

 

Remove the diagonal:

 

[TeslaTrek]

thanks.  It took 2 channel lock wrenches to loosen the diagonal.

 

I'll need to wait for the weekend to perform the test you mentioned.

 

thanks again.

 

/jim

[TeslaTrek]

Setup the Coronado today - beautiful day.  First I aligned the scope as I always do.  Sun in little finder.  With the diagonal removed I see a bright red sun and a fainter sun.  I assume this is a characteristic of the etalon.  (I used a piece of white cardboard because I was told never to look into the scope without the diagonal.)

 

 

 

The first element of the diagonal, that is towards the objective, looks very reflective with no sign of deterioration. At the eyepiece end, the filter is very reddish. I put the diagonal back and used my 25mm and nothing.   I took out the eyepiece from the diagonal and look through and see nothing.  Not a hint.

 

So I guess I need a new BF15 diagonal.

[BYoesle]

The "rusting" of the ITF can be subtle. You sometimes need to examine the front element of the BF with a bight light from differing light angles to detect deterioration of the reflective layers. See here and here.

 

It's rare that the order selection filter would deteriorate, but it can happen to the filter substrate.

 

A trip to Lunt will be definitive.

[TeslaTrek]

A 400 mile drive from san diego.  It might be worth a gamble just to buy a new bf filter and diagonal and try it versus the cost of either shipping or driving.

I'll let the group now however the results turn out. (Hopefully not something really dumb on my part)

[SteveC]

I would double check with Lunt on SolarMax repairs. I just called them today and was informed that they are not repairing SolarMax scopes at this time. My beloved SolarMax 40mm is heading into the trash I suspect. 

Edited by SteveC, 12 December 2024 - 12:53 PM.

[TeslaTrek]

I would double check with Lunt on SolarMax repairs. I just called them today and was informed that they are not repairing SolarMax scopes at this time. My beloved SolarMax 40mm is heading into the trash I suspect. 

Yikes!  I must have called them 6 times.  When I got through I was told to email them my problem.  I told them I did email them and the woman said then they will get to it when they do.  

 

I just want to know if I can purchased their BF15 (maybe their 6mm BF15)  to replace my apparently defective BF15 that it would be safe for viewing with my Coronado.  Lundt must be going through some difficult times.

[BYoesle]

Lunt is probably still a bit backlogged in replenishing stock to retailers from eclipse mania.

 

They also probably underestimated the increased workload that taking on Coronado repairs would put on them.

 

You should also check with Stellar Vision in Tucson. In the past they have done repair for Coronado telescopes, etalons, and blocking filters. They might even have access to a refurbished Coronado BF to exchange.

 

 

I just want to know if I can purchased their BF15 (maybe their 6mm BF15)  to replace my apparently defective BF15 that it would be safe for viewing with my Coronado. 

????

 

Lunt does not make a "BF15". Coronado made their blocking filters as BF10, BF15, and BF30.

 

Coronado Instruments Group catalog 2002

 

As with Coronado, Lunt blocking filters are similarly denoted by the size of the order selection bandpass  filter:

 

B500 = 5 mm diameter (for use with a 500 ml FL objective) DISCONTINUED

B600 = 6 mm diameter (for use with a up to 600 ml FL objective)

B1200 = 12 mm diameter (for use with up to a 1200 ml FL objective)

B1800 = 18 mm diameter (for use with up to a 1800 ml FL objective)

B3400 = 34 mm diameter (for use with up to a 3400 ml FL objective)

 

So you'd want to get the Lunt B1800 as a Coronado BF15 replacement just to be on the safe side. And it's always better to go larger for binoviewing, imaging, etc.

 

There are mixed opinions about the Lunt blocking filter compatibility used with a Coronado etalon, as etalon and blocking filter design parameters have changed over the years. Many have used them successfully, but there are likely no guarantees.

Edited by BYoesle, 12 December 2024 - 08:26 PM.

[TeslaTrek]

Lunt is probably still a bit backlogged in replenishing stock to retailers from eclipse mania.

 

They also probably underestimated the increased workload that taking on Coronado repairs would put on them.

 

You should also check with Stellar Vision in Tucson. In the past they have done repair for Coronado telescopes, etalons, and blocking filters. They might even have access to a refurbished Coronado BF to exchange.

 

 

????

 

Lunt does not make a "BF15". Coronado made their blocking filters as BF10, BF15, and BF30.

 

Cornado Blocking Filters 2002.jpg

Coronado Instruments Group catalog 2002

 

As with Coronado, Lunt blocking filters are similarly denoted by the size of the order selection bandpass  filter:

 

B500 = 5 mm diameter (for use with a 500 ml FL objective) DISCONTINUED

B600 = 6 mm diameter (for use with a up to 600 ml FL objective)

B1200 = 12 mm diameter (for use with up to a 1200 ml FL objective)

B1800 = 18 mm diameter (for use with up to a 1800 ml FL objective)

B3400 = 34 mm diameter (for use with up to a 3400 ml FL objective)

 

So you'd want to get the Lunt B1800 as a Coronado BF15 replacement just to be on the safe side. And it's always better to go larger for binoviewing, imaging, etc.

 

There are mixed opinions about the Lunt blocking filter compatibility used with a Coronado etalon, as etalon and blocking filter design parameters have changed over the years. Many have used them successfully, but there are likely no guarantees.

 

Well this is quite helpful.  I am weighing having a 90 mm Coronado as an awkward paperweight or spending $500 to see if I can bring it back to life.  Incidentally, I just got a curt replay from Lundt today.

 

  "Unfortunately at this time Lunt is no longer offering service for Coronado products."

 

However my question to them was:

 

   I have a Coronado SolarMax II 90mm.  There appears to be something wrong with my 1.25" diagonal with the  BF15 blocking filter.  Would one of your blocking filters work as a replacement?

 

Although they did not answer my question I did indeed get an answer.    I understand pressures on small business.  But if the response I got is representative of how they respond to other potential customers, then their future may not be so bright. (I think I understand small businesses.  I have been one since 1992 and have been growing consistently all these years keeping our customers number one.)

 

/vr

[BYoesle]

Incidentally, I just got a curt replay from Lundt (sic) today. "Unfortunately at this time Lunt is no longer offering service for Coronado products."

 

We don't really know what might be going on.

 

Another issue could be that MEADE Coronado may not have disappeared as a cooperate entity and might have placed a legal restraint on Lunt form doing any repairs:

 

As a disclaimer: Lunt maintain the right to discontinue this service at any time. Coronado may resurface tomorrow. My goal is to service both Lunt and Coronado products until that happens.

Andy Lunt

 

It might be coincidental with this announcement today, or it might not.

 

 

Although they did not answer my question I did indeed get an answer.    I understand pressures on small business.  But if the response I got is representative of how they respond to other potential customers, then their future may not be so bright. (I think I understand small businesses.  I have been one since 1992 and have been growing consistently all these years keeping our customers number one.)

 

The same legal consideration may be involved in them not responding to using a Lunt BF with a Coronado etalon, which in the past they have declined to recommend.  How many car companies would recommend using their transmissions in another company's cars?

 

I've stated that some have tried it and it might work. So your on your own to purchase one to see whether or not it will, or contact Stellar Vision as previously advised.

Edited by BYoesle, 13 December 2024 - 09:45 PM.

[SteveC]

Yikes!  I must have called them 6 times.  When I got through I was told to email them my problem.  I told them I did email them and the woman said then they will get to it when they do.  

 

I just want to know if I can purchased their BF15 (maybe their 6mm BF15)  to replace my apparently defective BF15 that it would be safe for viewing with my Coronado.  Lundt must be going through some difficult times.

Faye, Lunt's customer rep, and a great person to deal with for sales and service, is no longer with the company. I was a bit sorry to hear that when I specifically asked to speak to her. Nevertheless, everytime I've called over the years they've answered the first time or promptly returned my call after leaving a message. It was same this time, just the answer was not what I was hoping for, but it was a business decision, and I can accept that without an explanation. 

[SteveC]

Lunt is probably still a bit backlogged in replenishing stock to retailers from eclipse mania.

 

They also probably underestimated the increased workload that taking on Coronado repairs would put on them.

 

You should also check with Stellar Vision in Tucson. In the past they have done repair for Coronado telescopes, etalons, and blocking filters. They might even have access to a refurbished Coronado BF to exchange.

I contacted Stellar Vision and they said they could fix my 40mm SolarMax.  Not only that, but they said the could collimate the mirrors on my 7" IM Mak which has been out of action for 10 years. I've never gotten out of sorts about that since since replacements for both my scopes are  a 60mm Lunt DS MT and a TEC140. 

 

Thank you for the contact. I owe you a beer.

Edited by SteveC, 14 December 2024 - 10:29 AM.

[BYoesle]

 

Thank you for the contact. I owe you a beer. 

 

Cheers! 

 

 

[TeslaTrek]

I just went and ordered the 6 mm BF15 from Lundt.  If it does not work, meaning if that does not solve my problem,  I'll return it.

 

Also I contacted Stellar Vision.  Very quick response.  I may be heading out for a road trip to Tuscon. 

[BYoesle]

I just went and ordered the 6 mm BF15 from Lundt.

 

Hi Jim,

 

Post #18 showed how the Lunt B600 with the 6 mm blocking filter is good for telescopes up to 600 mm in focal length. The SM90 telescope has a focal length of 800 mm, and therefore it would need at least the B1200 (12 mm) blocking filter in order to have an un-vignetted field at low power. The Coronado BF15 you want to replace has a filter diameter of 15 mm, and you apparently have bought one less than half that diameter.

 

The disc of the sun has a diameter of roughly the FLobjective divided by 110 > 800/110 = 7.2 mm, therefore the B600 will not allow the entire disc of the sun to be viewed.

Edited by BYoesle, 15 December 2024 - 10:02 AM.