[Gary R]

Have been ripping up the net over comparisons of various spotting scopes. Seem to keep going back to the Celestron Regal 100 as a "best buy" for the money. Anyone care to support this choice or offer a better one? My biggest need is resolution at extreme range like 600 meters.

[mooreorless]

Hi Gary, Welcome to Birdforum! I was wondering if you read any of the Regal 100 threads? 600 yds. is that to identify, see bullet holes etc. ? Also have you read" Premium Spotting Scopes in Review" on the 6mm BR site?

[FrankD]

600 yard bullet holes? I would just love to see the range of that size!



I do not think the original poster will find a better value (performance/price) in a 100 mm scope. The interesting part is he will be able to use some higher end fixed power eyepieces to get even more magnification over the factory supplied zoom. I would love to see what a high-end short focal length eyepiece would do out of the Regal 100.

[mooreorless]

For the price of the Regal 100 or less you can get an Orion 100ED refractor if you don't need WP, not carrying it very far and have a mount to handle it. It will handle what ever power you can use on that day.

Frank I should of said, try to see bullet holes at 600 yds. and I would like to see that range myself.

[Gary R]

Originally Posted by mooreorless

Hi Gary, Welcome to Birdforum! I was wondering if you read any of the Regal 100 threads? 600 yds. is that to identify, see bullet holes etc. ? Also have you read" Premium Spotting Scopes in Review" on the 6mm BR site?

Bullet holes are exactly what I have in mind. I have a Celestron C90 and a C135 but they just are not sharp. I wonder if the fault is in the eyepieces? What would you recommend in an eyepiece for either if you feel they have the capability of resolution at that distance. Is it possible without ED glass?

[TargetTerror]

Originally Posted by Gary R

Bullet holes are exactly what I have in mind. I have a Celestron C90 and a C135 but they just are not sharp. I wonder if the fault is in the eyepieces? What would you recommend in an eyepiece for either if you feel they have the capability of resolution at that distance. Is it possible without ED glass?

At 600 yards, you are going to be much more limited by mirage than by your scope selection. Even at 200 yards, bullet holes can be hard to see when the mirage is bad. My recommendation is to get a bunch of shoot-n-c targets. They leave a big, fluorescent splatter ring where the bullet hits the target, and greatly extend your range. Even with shoot-n-c targets, mirage will still likely limit what you can see.

[mooreorless]

Yea, they talk about mirage in the 6 BR review, Pentax 100mm spotter tested on there. I have used a Meade ETX 90 to spot 6mm bullet holes at 300 yds. with no trouble, not much mirage that day, 300 yds. max at that range.

[Gary R]

Talk to me about eyepieces. What would you recommend for use in either the c90 or the c135 for 600 meter use. Conditions are just that and cannot be conquered so lets just talk performance in "clean air". I shoot registered targets so shoot n see are out of the question.

[FrankD]

Gary,

The beauty of our eyepiece suggestions is that they should work in both your C-series scopes and the Celestron Regal series, if you decide to go that route.

As with everything else your eyepiece suggestions are going to depend on how much you want to spend. There are some pretty decent eyepieces in the $50-$60 range and then some really good to absolutely excellent ones in the $300+ range.

Here are some suggestions at various price points:

Under $100:

Celestron Xcel LX
Meade HD 60
Agena Astro ED

Under $200

Orion Stratus
Baader Hyperion
Meade SWA or UWA
Pentax XF

At or under $300:

Vixen LVW
Pentax XW

That is the limite of the price range that I have experience with. Once you get higher than that then you are getting up there in Televue "country" and I have never owned one. Keep in mind that we are talking about fixed power eyepieces...not zooms. If you want the best after-market zoom then buy the Baader Hyperion Zoom. They usually sell for around $230 at various optics retailers.

Hope this helps.

[Gary R]

Frank....are the differences tiny or do they grow exponentially? Is there a "best buy" there or is it a matter of choice? I am always interested in the best for the least but then, who isn't?

[RJM]

Before you buy any eyepieces you need to test your scopes optics for collimation error. A compound scope like your C90/135 is very prone to this error and even slight miscollimation will render your choice of eyepiece moot. As for eyepieces, if eyerelief is not a concern a simple plossl design is your best choice for your application. TeleVue makes the best and they are relatively cheap compared to other complex designs.

[Gary R]

Where to send these for collumination?

[FrankD]

Gary,

I would follow RJM's advice first.

Assuming the scope is properly aligned then you can experiment with different eyepieces. I have to readily admit that my experience and preferences for tinkering with astro eyepieces is restricted to longer focal lengths (20-25 mm). In the spotter that I am using them in they result in relatively low magnifications (20-25x). I am looking for relatively wide fields with a bright, low color fringing image. Maximum magnification isn't something I have an interest in. I use my scopes to pan over large areas of the sky in search of birds of prey primarily. I also use them for observing waterfowl which is why I have a zoom for both. That is a secondary concern for me though.

I would think for your application then that you would the sharpest image you can get in the center of the field of view. Edge performance would be secondary to an extent. The width of the field of view would also be secondary. RJM's suggestion of a relatively simple plossl design would tend to be a good one. Their narrow field of view and, depending on which brand, occasionally poor edge performance, will not matter for your application as long as the center of the field is sharp and bright. The only "bad" issue with plossls is eye relief. If I remember the formula correctly the eye relief of any given plossl is approximately 2/3rds the focal length of the eyepiece. So, if you have a 12 mm focal length plossl then the eye relief will only be about 8 mm...pretty short in the grand scheme of things.

Some of the "super plossl" designs such as the Mead HD60 or Celestron Xcel LX don't suffer from these issues and are, in my opinion the best "bang for the buck" in terms of performance versus price. At $65-$75 they offer very good color fringing control, good color representation and a very sharp image. A step up from them would be the Orion Stratus or Baader Hyperion. They offer slightly better contrast and a somewhat wider apparent field of view (68 versus 60 degrees). At the $140 or so they usually sell for they are still a very good bargain.

A word of advice, if you want to find some excellent deals on astro eyepieces I would suggest you sign up for astromart. There is an $11 registration fee but their classified section is second to none when it comes to used, but in new condition, astro eyepieces. I have purchased several eyepieces there recently for less than half of their new price and yet the eyepieces are in new condition. New ads pop up daily and you almost have to check several times per day if you want to grab the best deals but it is certainly worth it.

Hope this helps.

[mooreorless]

Bob A [SD] has the newer style C90 and seems to like it a lot. I am not sure what eyepieces he has with it.

[Gary R]

Frank......... I should probably have the collumination checked first, can you recommend a repair facility?

[FrankD]

Gary,

I wish I could help but I have no experience with repairs or maintenance on telescopes. I haven't even had to send any of my spotters in for repairs. I would assume that you could contact the manufacturer of the product for any type of repairs that need to be completed. There may be some independent optics repair/adjustment shops as well but I have no information on them.

[mooreorless]

If it is Celestron and if there is a warranty and if Gary bought it at a Celestron dealer and kept the original receipt than it would/could just cost shipping. I couldn't find any information on the C135.

[RJM]

Verify collimation with a simple home test. Google and you will find lot's of How To's. Not sure if those scopes have DIY collimation adjustment screws though.

[mooreorless]

http://legault.perso.sfr.fr/collim.html

http://sctscopes.net/SCT_Tips/Mainte...llimation.html

The first link shows the difference in quality of the view. If Gary would check the C90 and C135 using a christmas ball outside during the sunny day he could check if there is a problem. Second link shows what the out of focus image might look like with a tilt that shows out of alignment.

[Gary R]

Assuming the collumination is correct and the problem is a poor eyepiece will the C90 or the C135 outperform the Regal 100 because of the longer focal length of the C scopes? No sense to buy another scope if I can get the performance I need with a simple change of eyepieces.

[IvanCavallazzi]

Originally Posted by Gary R

Assuming the collumination is correct and the problem is a poor eyepiece will the C90 or the C135 outperform the Regal 100 because of the longer focal length of the C scopes? No sense to buy another scope if I can get the performance I need with a simple change of eyepieces.

No. The focal length just means you will acquire different magnification with one specific eyepiece.
(For example a 17mm eye piece will show a far bigger magnification in the C90 if compared to the regal)

C90, C5 and so... are cheaper because the design(catadiotric) is cheaper to make.

It uses mirror to condense the light instead of lenses.

The design do not show the same contrast you will be able to find in refractors.

If you want the best image possible, refractors are the way.
The only way to see even better images than spotting scopes is to remove the porro prism and using a star diagonal(reversed images left to right).

[henry link]

A "better" eyepiece is not going to help. Cheap simple eyepieces will show all the detail available in the field center of your scope's image if you're using enough magnification. Even edge sharpness should be OK with a cheap eyepiece since your scopes present an easy f/10 light cone.

[Gary R]

Henry..... would you then suppose the problem with non sharp immages is in the collumination?

[RJM]

Gary, there are many variables that conspire to prevent you from achieving your goal. Even if your optics were perfect the dust/turbulence in the atmosphere will tend to blur your images at the high magnifications needed to resolve the target at distance. Even if the atmosphere was perfectly clear/stable the high magnification you will need yields small exit pupils that also affect your ability to resolve fine detail.

You can determine the minimum magnification needed by measuring the furthest distance that you can see bullet holes clearly naked eye and then dividing this distance into your expected target range. So say you can see holes clearly with your targeting eye at 6m and you expect to shoot at 600m, 600/6=100x minimum magnification. Practically 100x is only doable on the C135 as you really don't want an exit pupil less than 1mm as your eye's ability to resolve detail will suffer. To get 100x on a C135 requires and eyepiece with a focal length of ~12mm. As Henry said, virtually any eyepiece design will be "good enough" in these CAT scopes. The main feature you need to look for is comfortable eyerelief.

[normjackson]

Yesterday evening watched a bit of "Surviving the Cut" about training snipers for military :
http://dsc.discovery.com/videos/surv...ance-test.html
Would have thought some kit which allowed only near infrared onto a CMOS or CCD device of reasonable resolution could work well. Presumably wouldn't need a highly colour corrected scope either In the stuff I watched, the snipers "helpers" used small Leupold Golden Ring scopes and the adjudicator a Kowa Highlander bin by the look of it $$$$

Wonder if Gary checked his scopes...